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1
Ibrahim, Mohammad H. A., and Alexander Steinbüchel. "Poly(3-Hydroxybutyrate) Production from Glycerol by Zobellella denitrificans MW1 via High-Cell-Density Fed-Batch Fermentation and Simplified Solvent Extraction." Applied and Environmental Microbiology 75, no. 19 (August 7, 2009): 6222–31. http://dx.doi.org/10.1128/aem.01162-09.
Повний текст джерелаАнотація:
ABSTRACT Industrial production of biodegradable polyesters such as polyhydroxyalkanoates is hampered by high production costs, among which the costs for substrates and for downstream processing represent the main obstacles. Inexpensive fermentable raw materials such as crude glycerol, an abundant by-product of the biodiesel industry, have emerged to be promising carbon sources for industrial fermentations. In this study, Zobellella denitrificans MW1, a recently isolated bacterium, was used for the production of poly(3-hydroxybutyrate) (PHB) from glycerol as the sole carbon source. Pilot-scale fermentations (42-liter scale) were conducted to scale up the high PHB accumulation capability of this strain. By fed-batch cultivation, at first a relatively high cell density (29.9 ± 1.3 g/liter) was obtained during only a short fermentation period (24 h). However, the PHB content was relatively low (31.0% ± 4.2% [wt/wt]). Afterwards, much higher concentrations of PHB (up to 54.3 ± 7.9 g/liter) and higher cell densities (up to 81.2 ± 2.5 g/liter) were obtained by further fed-batch optimization in the presence of 20 g/liter NaCl, with optimized feeding of glycerol and ammonia to support both cell growth and polymer accumulation over a period of 50 h. A high specific growth rate (0.422/h) and a short doubling time (1.64 h) were attained. The maximum PHB content obtained was 66.9% ± 7.6% of cell dry weight, and the maximum polymer productivity and substrate yield coefficient were 1.09 ± 0.16 g/liter/h and 0.25 ± 0.04 g PHB/g glycerol, respectively. Furthermore, a simple organic solvent extraction process was employed for PHB recovery during downstream processing: self-flotation of cell debris after extraction of PHB with chloroform allowed a convenient separation of a clear PHB-solvent solution from the cells. Maximum PHB recovery (85.0% ± 0.10% [wt/wt]) was reached after 72 h of extraction with chloroform at 30°C, with a polymer purity of 98.3% ± 1.3%.
2
Montiel-Jarillo, Gabriela, Diego A. Morales-Urrea, Edgardo M. Contreras, Alex López-Córdoba, Edwin Yesid Gómez-Pachón, Julián Carrera, and María Eugenia Suárez-Ojeda. "Improvement of the Polyhydroxyalkanoates Recovery from Mixed Microbial Cultures Using Sodium Hypochlorite Pre-Treatment Coupled with Solvent Extraction." Polymers 14, no. 19 (September 21, 2022): 3938. http://dx.doi.org/10.3390/polym14193938.
Повний текст джерелаАнотація:
The use of mixed microbial cultures (MMC) and organic wastes and wastewaters as feed sources is considered an appealing approach to reduce the current polyhydroxyalkanoates (PHAs) production costs. However, this method entails an additional hurdle to the PHAs downstream processing (recovery and purification). In the current work, the effect of a sodium hypochlorite (NaClO) pre-treatment coupled with dimethyl carbonate (DMC) or chloroform (CF) as extraction solvents on the PHAs recovery efficiency (RE) from MMC was evaluated. MMC were harvested from a sequencing batch reactor (SBR) fed with a synthetic prefermented olive mill wastewaster. Two different carbon-sources (acetic acid and acetic/propionic acids) were employed during the batch accumulation of polyhydroxybutyrate (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) from MMC. Obtained PHAs were characterized by 1H and 13C nuclear magnetic resonance, gel-permeation chromatography, differential scanning calorimetry, and thermal gravimetric analysis. The results showed that when a NaClO pre-treatment is not added, the use of DMC allows to obtain higher RE of both biopolymers (PHB and PHBV), in comparison with CF. In contrast, the use of CF as extraction solvent required a pre-treatment step to improve the PHB and PHBV recovery. In all cases, RE values were higher for PHBV than for PHB.
3
Samrot, Antony V., Sree K. Samanvitha, N. Shobana, Emilin R. Renitta, P. Senthilkumar, Suresh S. Kumar, S. Abirami, et al. "The Synthesis, Characterization and Applications of Polyhydroxyalkanoates (PHAs) and PHA-Based Nanoparticles." Polymers 13, no. 19 (September 27, 2021): 3302. http://dx.doi.org/10.3390/polym13193302.
Повний текст джерелаАнотація:
Polyhydroxyalkanoates (PHAs) are storage granules found in bacteria that are essentially hydroxy fatty acid polyesters. PHA molecules appear in variety of structures, and amongst all types of PHAs, polyhydroxybutyrate (PHB) is used in versatile fields as it is a biodegradable, biocompatible, and ecologically safe thermoplastic. The unique physicochemical characteristics of these PHAs have made them applicable in nanotechnology, tissue engineering, and other biomedical applications. In this review, the optimization, extraction, and characterization of PHAs are described. Their production and application in nanotechnology are also portrayed in this review, and the precise and various production methods of PHA-based nanoparticles, such as emulsion solvent diffusion, nanoprecipitation, and dialysis are discussed. The characterization techniques such as UV-Vis, FTIR, SEM, Zeta Potential, and XRD are also elaborated.
4
Rocha, Marisa Cristina Guimarães, Nancy Isabel Alvarez Acevedo, and Carlos Eduardo Nazareth de Oliveira. "Mechanical and Morphological Properties of PHB/Oil-Free Coffee Dregs (OFCD) Composites." Materials Science Forum 1079 (December 26, 2022): 93–102. http://dx.doi.org/10.4028/p-k5hv1o.
Повний текст джерелаАнотація:
Poly(3-hydroxybutyrate) (PHB) and coffee dregs (CDs) are both biodegradable materials. The latter are household wastes with no commercial value that are discarded in landfills mixed with other organic wastes. PHB has properties equivalent to polypropylene (PP), but its prohibitive cost restricts its field of application. The incorporation of this residue in a PHB matrix is a way to obtain materials with a high cost/benefit ratio. The aim of this work was to investigate the effect of adding oil-free coffee dregs (OFCDs) on the mechanical and morphological properties of PHB. Soxhlet extraction using ethanol as a solvent was used to obtain OFCDs. The PHB/OFCD composites were prepared in a twin-screw extruder. Standardized methods were used to evaluate the tensile and flexural properties. The test specimens were obtained by compression molding. Scanning electron microscopy (SEM) was applied to evaluate the morphology of the composites obtained. The data obtained showed that the incorporation of 15 wt.% of OFCD caused no significant differences in the tensile modulus, tensile strength and flexural modulus. The flexural strength decreased with the incorporation of OFCD in the PHB. However, the material obtained was interesting, since it was more attractive in terms of cost and environmental impact. SEM micrographs showed good dispersion of OFCD in PHB when the OFCD content was 5 wt.%. However, when higher levels of residues were incorporated in the PHB, the formation of agglomerates became evident. Poor interfacial adhesion between the filler and matrix was indicated by the cracks and voids revealed in the micrographs. The results obtained indicated that PHB/OFCD composites prepared with 15 wt.% of OFCD particles have potential to be used in the production of PHB materials that require high stiffness, adequate strength, and lower cost, such as sheets and thermoformed products for food, medical, personal care and laboratory applications
5
Fiorese, Mônica Lady, Filomena Freitas, Joana Pais, Ana Maria Ramos, Gláucia M. F. de Aragão, and Maria A. M. Reis. "Recovery of polyhydroxybutyrate (PHB) from Cupriavidus necator biomass by solvent extraction with 1,2-propylene carbonate." Engineering in Life Sciences 9, no. 6 (December 2009): 454–61. http://dx.doi.org/10.1002/elsc.200900034.
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B, Viswapriya, Balamurugan V, and Jayaprakash K. "ISOLATION OF SEAWEED ASSOCIATED BACTERIA'S AND THEIR PRODUCTION OF BIOPOLYMER BY SOLID-STATE FERMENTATION." International journal of multidisciplinary advanced scientific research and innovation 1, no. 7 (September 30, 2021): 134–41. http://dx.doi.org/10.53633/ijmasri.2021.1.7.04.
Повний текст джерелаАнотація:
Plastic material is any of a wide range of synthetic or semi-synthetic organic solids that are moldable. Plastics are typically organic polymers of high molecular mass, but they often contain other substances. They are usually synthetic, most commonly derived from petrochemicals, but many are partially natural. Environmental pollution by the disposal of non-degradable conventional plastics is a fast-growing problem worldwide, especially in India. Nowadays, plastics are replacing by other constructional materials like glass, wood, metal in numerous applications. In this study, there has been considerable interest in the development and production of biodegradable polymer to solve the current problem of pollution caused by the continuous use of synthetic polymer from seaweed associated Bactria. . Based on the dry weight of total biopolymer content, the strain SBT 09 showed maximum accumulation and selected for optimizing at different pH, temperature, salinity, carbon, and nitrogen source and the peak time of PHB accumulation. Based on the biochemical tests, the strain SBT 09 was found.The optimum pH, temperature, and salinity were found to be 7, 300C, and 5%. The peak time of PHB accumulation was found to be 36hrs. The best carbon and nitrogen source was found to be sucrose and (NH4)2 HPO4. The selected strain was mass cultured using the optimized media and PHB was extracted by solvent extraction. Keywords: Marine Bacteria, PHB, Biosynthesis, Biopolymer.
7
Filippi, Sara, Patrizia Cinelli, Andrea Mezzetta, Pietro Carlozzi, and Maurizia Seggiani. "Extraction of Polyhydroxyalkanoates from Purple Non-Sulfur Bacteria by Non-Chlorinated Solvents." Polymers 13, no. 23 (November 28, 2021): 4163. http://dx.doi.org/10.3390/polym13234163.
Повний текст джерелаАнотація:
In this study, non-chlorinated solvents such as cyclohexanone (CYC) and three ionic liquids, (ILs) (1-ethyl-3-methylimidazolium dimethylphosphate, [EMIM][DMP], 1-ethyl-3-methylimidazolium diethylphosphate, [EMIM][DEP] and 1-ethyl-3-methylimidazolium methylphosphite, [EMIM][MP]) were tested to extract polyhydroxyalkanoates (PHAs) from the purple non-sulfur photosynthetic bacterium (PNSB) Rhodovulumsulfidophilum DSM-1374. The photosynthetic bacterium was cultured in a new generation photobioreactor with 4 L of working volume using a lactate-rich medium. The extracted PHAs were characterized using a thermogravimetric analysis, differential scanning calorimetry, infrared spectroscopy, proton nuclear magnetic resonance and gel permeation chromatography. The most promising results were obtained with CYC at 125 °C with an extraction time of above 10 min, obtaining extraction yields higher than 95% and a highly pure poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-HV) with around 2.7 mol% of hydroxylvalerate (HV). A similar yield and purity were obtained with chloroform (CHL) at 10 °C for 24 h, which was used as the referent solvent Although the three investigated ILs at 60 °C for 4 and 24 h with biomass/IL up to 1/30 (w/w) obtained PHAs strongly contaminated by cellular membrane residues, they were not completely solubilized by the investigated ILs.
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Martínez-Herrera, Raul E., María E. Alemán-Huerta, Verónica Almaguer-Cantú, Walfred Rosas-Flores, Víctor J. Martínez-Gómez, Isela Quintero-Zapata, Gildardo Rivera, and O. Miriam Rutiaga-Quiñones. "Efficient recovery of thermostable polyhydroxybutyrate (PHB) by a rapid and solvent-free extraction protocol assisted by ultrasound." International Journal of Biological Macromolecules 164 (December 2020): 771–82. http://dx.doi.org/10.1016/j.ijbiomac.2020.07.101.
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de Oliveira Schmidt, Vanessa Kristine, Evelise Fonseca dos Santos, Débora de Oliveira, Marco Antônio Záchia Ayub, Karina Cesca, Paulo Roberto Dall Cortivo, Cristiano José de Andrade, and Lilian Raquel Hickert. "Production of Polyhydroxyalkanoates by Bacillus megaterium: Prospecting on Rice Hull and Residual Glycerol Potential." Biomass 2, no. 4 (December 16, 2022): 412–25. http://dx.doi.org/10.3390/biomass2040026.
Повний текст джерелаАнотація:
The production of polyhydroxyalkanoates (PHAs) by Bacillus megaterium using industrial residues, crude glycerol from biodiesel synthesis and rice hull hydrolysate (RHH), as low-cost carbon sources was investigated. The experiments were conducted by shaking flasks at 30 °C and 180 rpm up to 72 h. The extraction of PHA was carried out using sodium hypochlorite to make its recovery more environmentally friendly by avoiding organic solvents (chloroform). The yields of PHA varied depending on the extraction method. A total of 33.3% (w·w−1) (mixing chloroform: sodium hypochlorite) and 52.5% (w·w−1) (sodium hypochlorite only) were obtained using glycerol and glucose as a carbon source, respectively. Preliminary experiments using RHH as a carbon source Indicated a yield of PHA of 11% (w·w−1) (chloroform). The PHA produced had thermal properties, such as transition temperature, similar to the commercial polyhydroxybutyrate (PHB).
10
Dunnivant, Frank M., and Alan W. Elzerman. "Determination of Polychlorinated Biphenyls in Sediments, Using Sonication Extraction and Capillary Column Gas Chromatography-Electron Capture Detection with Internal Standard Calibration." Journal of AOAC INTERNATIONAL 71, no. 3 (May 1, 1988): 551–56. http://dx.doi.org/10.1093/jaoac/71.3.551.
Повний текст джерелаАнотація:
Abstract A sonication technique is presented for the extraction of polychlorinated biphenyls (PCBs) from sediments. In addition, a quantitation scheme is described which allows peak-specific and, in many cases, congener-specific determination of PCBs. PCBs are quantitated by capillary column gas chromatography-electron capture detection, with internal standard calibration. Results utilizing sonication extraction were compared with those obtained by Soxhlet and steam distillation extractions of 3 U.S. Environmental Protection Agency (EPA) quality control sediment samples and 3 lake sediments known to be contaminated with PCBs. Environmental lake sediments were extracted wet, with no drying prior to extraction. Recoveries by each technique varied depending on the sediment sample being extracted and degree of chlorination of PCB congeners. With proper selection of extraction solvent, the sonication technique can recover amounts of PCBs equivalent to and sometimes greater than recoveries by the Soxhlet or steam distillation techniques. A 24-h quiescent period in the extraction solvent between 2 sonications improved extraction efficiency for 2 freeze-dried sediments but did not affect results obtained for 3 environmentally contaminated sediments that were extracted without drying. Replacement of Soxhlet extraction with the sonication technique results in reduced sample preparation time, decreased volumes of solvents and sample, and substitution of common laboratory glassware in place of fragile, expensive Soxhlet glassware. Sonication extraction can also improve precision compared with Soxhlet extraction
11
Venkatesan, Thamizhiniyan, Young-Woong Choi, and Young-Kyoon Kim. "Impact of Different Extraction Solvents on Phenolic Content and Antioxidant Potential of Pinus densiflora Bark Extract." BioMed Research International 2019 (July 29, 2019): 1–14. http://dx.doi.org/10.1155/2019/3520675.
Повний текст джерелаАнотація:
It is well established that various extraction factors, including the method, temperature, time, and solvent system, significantly influence the antioxidant quality of plant-derived products. Previously, we observed that extraction of Pinus densiflora bark (PDB) by the most common traditional Soxhlet method using water at two different temperature conditions 60°C and 100°C for 6-15 h noticeably altered their antioxidant quality. In this study, we examined the impact of different extraction solvents such as ethanol, methanol, isopropanol, acetonitrile, and acetone at a different percentage with water (vol/vol) on antioxidant efficiency as well as the total phenolic content (TPC) of PDB extracts. Among the fourteen different PDB extracts, the extracts obtained from 20% ethanol (E20), 40% ethanol (E40), and 20% acetonitrile (ACN20) showed more significant antioxidant potential, as well as high total phenol content (TPC). Extracts from other aqueous mixtures of organic solvents such as isopropanol, acetone, and methanol, as well as water, showed lesser antioxidant capacity and also had less TPC compared to these three most active extracts, E20, E40, and ACN20. Moreover, using ethanol at 100% for extraction significantly decreased the TPC and antioxidant capacity of PDB extracts. Data are implicating that an increased phenolic content in PDB extracts proportionally increases their antioxidant efficiency.
12
Ren, Yong-Lin, and James M. Desmarchelier. "Release of Fumigant Residues from Grain by Microwave Irradiation." Journal of AOAC INTERNATIONAL 81, no. 3 (May 1, 1998): 673–78. http://dx.doi.org/10.1093/jaoac/81.3.673.
Повний текст джерелаАнотація:
abstract Multiresidue analysis of fumigants is important because of their widespread use on staple foodstuffs, such as grain. Fumigants are usually extracted from grain either by solvent extraction or by purgeand- trap techniques. In this paper, fumigant residues in wheat were "extracted" by a microwave procedure. Wheat, in gas-tight Erlenmeyer flasks, was placed in a domestic microwave oven, and fumigants were released into the headspace by microwave irradiation. Power settings for maximum release of fumigants were determined for CH3Br PH3, CS2, and COS. Recoveries of fortified samples were >90%. Completeness of extraction was assessed from the amount of fumigant retained by the microwave-irradiated wheat. This amount, determined from both solvent extraction and from further microwave irradiation, was always small(<5℅ of the amount obtained from the initial procedure). Limits of quantitation were <1 ng/g for ChhBr, PH3, and CS2. These low limits were essentially due to the absence of interference from solvents. The microwave method is rapid and solvent-free. However, care is required in selecting the appropriate power setting. The safety implications of heating sealed flasks in microwave ovens should be noted.
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de Souza Reis, Guilherme A., Michiel H. A. Michels, Gabriela L. Fajardo, Ischa Lamot, and Jappe H. de Best. "Optimization of Green Extraction and Purification of PHA Produced by Mixed Microbial Cultures from Sludge." Water 12, no. 4 (April 21, 2020): 1185. http://dx.doi.org/10.3390/w12041185.
Повний текст джерелаАнотація:
Sludge from municipal wastewater treatment systems can be used as a source of mixed microbial cultures for the production of polyhydroxyalkanoates (PHA). Stored intracellularly, the PHA is accumulated by some species of bacteria as energy stockpile and can be extracted from the cells by reflux extraction. Dimethyl carbonate was tested as a solvent for the PHA extraction at different extraction times and biomass to solvent ratios, and 1-butanol was tested for purifying the obtained PHA at different purification times and PHA to solvent ratios. Overall, only a very small difference was observed in the different extraction scenarios. An average extraction amount of 30.7 ± 1.6 g of PHA per 100 g of biomass was achieved. After purification with 1-butanol, a visual difference was observed in the PHA between the tested scenarios, although the actual purity of the resulting samples did not present a significant difference. The overall purity increased from 91.2 ± 0.1% to 98.0 ± 0.1%.
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Makoś-Chełstowska, Patrycja, Edyta Słupek, Karolina Kucharska, Aleksandra Kramarz, and Jacek Gębicki. "Efficient Extraction of Fermentation Inhibitors by Means of Green Hydrophobic Deep Eutectic Solvents." Molecules 27, no. 1 (December 28, 2021): 157. http://dx.doi.org/10.3390/molecules27010157.
Повний текст джерелаАнотація:
The methods for hydrogen yield efficiency improvements, the gaseous stream purification in gaseous biofuels generation, and the biomass pretreatment are considered as the main trends in research devoted to gaseous biofuel production. The environmental aspect related to the liquid stream purification arises. Moreover, the management of post-fermentation broth with the application of various biorefining techniques gains importance. Chemical compounds occurring in the exhausted liquid phase after biomass pretreatment and subsequent dark and photo fermentation processes are considered as value-added by products. The most valuable are furfural (FF), 5-hydroxymethylfurfural (HMF), and levulinic acid (LA). Enriching their solutions can be carried with the application of liquid–liquid extraction with the use of a suitable solvent. In these studies, hydrophobic deep eutectic solvents (DESs) were tested as extractants. The screening of 56 DESs was carried out using the Conductor-like Screening Model for Real Solvents (COSMO-RS). DESs which exposed the highest inhibitory effect on fermentation and negligible water solubility were prepared. The LA, FF, and HMF were analyzed using FT-IR and NMR spectroscopy. In addition, the basic physicochemical properties of DES were carefully studied. In the second part of the paper, deep eutectic solvents were used for the extraction of FF, LA, and HMF from post-fermentation broth (PFB). The main extraction parameters, i.e., temperature, pH, and DES: PFB volume ratio (VDES:VPFB), were optimized by means of a Box–Behnken design model. Two approaches have been proposed for extraction process. In the first approach, DES was used as a solvent. In the second, one of the DES components was added to the sample, and DES was generated in situ. To enhance the post-fermentation broth management, optimization of the parameters promoting HMF, FF, and LA extraction was carried under real conditions. Moreover, the antimicrobial effect of the extraction of FF, HMF, and LA was investigated to define the possibility of simultaneous separation of microbial parts and denatured peptides via precipitation.
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Thiele, Isabel. "Scale-Up of the Downstream Process for Polyhydroxyalkanoate Copolymer P(HB‑co-HHx) Extraction with Nonhalogenated Solvents." Journal of Siberian Federal University. Biology 14, no. 4 (December 2021): 454–64. http://dx.doi.org/10.17516/1997-1389-0364.
Повний текст джерелаАнотація:
Biobased and biodegradable polyhydroxyalkanoates (PHAs) are promising alternatives to common plastics. Due to their high production costs, only a minimal share of global plastic production is composed of PHA. A major contributor to the high costs minimizing the potential to occupy a larger market share is the downstream process. To obtain high recovery yields and pure products, most approaches rely on large amounts of solvents. While short-chain-length PHA (scl-PHA) is poorly soluble in nonhalogenated solvents, medium-chain-length PHA (mcl-PHA) was shown to be soluble in nonhalogenated solvents. In this study, an approach to recover poly(hydroxybutyrate-co-hydroxyhexanoate) with acetone and 2-propanol was scaled up 30-fold to 300 g of lyophilized cells per recovery cycle. High PHA purities of 90–100 % were reached from extractions at moderate temperatures from 30–58 °C. In two-stage extractions, up to 100 % PHA was recovered, while the molecular weight was not reduced. Solvents were recovered by distillation in a concentration step and after precipitation. Furthermore, the material properties were analyzed. PHA recovered from the distillation bottom had an increased HHx content compared to the first and second extractions using recovered solvents and was of low purity, indicating efficient and pure precipitation of the recovered PHA during the 2-stage extractions
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Souza, Hiléia K. S., Mariana Matos, Maria A. M. Reis, José A. Covas, and Loïc Hilliou. "Can Biomass Mastication Assist the Downstreaming of Polyhydroxyalkanoates Produced from Mixed Microbial Cultures?" Molecules 28, no. 2 (January 12, 2023): 767. http://dx.doi.org/10.3390/molecules28020767.
Повний текст джерелаАнотація:
Polyhydroxyalkanoates (PHAs) are natural polyesters which biodegrade in soils and oceans but have more than double the cost of comparable oil-based polymers. PHA downstreaming from its biomass represents 50% of its overall cost. Here, in an attempt to assist downstreaming, mastication of wet biomasses is tested as a new mechanical continuous biomass pretreatment with potential for industrial upscaling. Downstreaming conditions where both product recovery and purity are low due to the large amount of treated wet biomass (50% water) were targeted with the following process: extraction of 20 g in 100 mL solvent at 30 °C for 2 h, followed by 4.8 h digestion of 20 g in 0.3 M NaOH. Under the studied conditions, NaOH digestion was more effective than solvent extraction in recovering larger PHA amounts, but with less purity. A nearly 50% loss of PHA was seen during digestion after mastication. PHAs downstreamed by digestion with large amounts of impurities started to degrade at lower temperatures, but their melt elasticity was thermally stable at 170 °C. As such, these materials are attractive as fully PHA-compatible processing aids, reinforcing fillers or viscosity modifiers. On the other hand, wet biomass mastication before solvent extraction improves PHA purity and thermal stability as well as the melt rheology, which recovers the viscoelasticity measured with a PHA extracted from a dried biomass.
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Mokhtari, Bahram, and Kobra Pourabdollah. "Extraction of s-block metals by nano-baskets of calix[4]crown-3." Canadian Journal of Chemistry 90, no. 6 (June 2012): 560–66. http://dx.doi.org/10.1139/v2012-020.
Повний текст джерелаАнотація:
Three kinds of nano-baskets including 1,2-alternate and cone conformers of di-ionizable p-tert-butylcalix[4]arene-1,2-crown-3 and the cone conformer of p-tert-butylcalix[4]arene-1,2-thiacrown-3 were synthesized and the competitive solvent extractions of alkali and alkaline earth metal cations were studied. The novelty of this study is including three binding units of the calixarene’s bowl, the crown ether’s ring, and electron-donor ionizable moieties in a unique scaffold, in which their sizes were selected based upon their complexation ability to show equal binding tendency towards the cations. The objective of this work is to assess the extraction efficiency, selectivity, and pH1/2 of such complexes. The results of solvent extraction experiments indicated that these compounds were effective extractants of alkali and alkaline earth metal cations. Their selectivities were greatly influenced by the acidity of the solution and the conformations of the calixcrown. One conformer was highly selective to Na+ and the other to Ba2+ in acidic and basic solutions, respectively.
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Desmarchelier, James M., Sylvia E. Allen, and Yong-Lin Ren. "Comparison of Six Methods for Determining Aged Phosphine Residues in Wheat." Journal of AOAC INTERNATIONAL 81, no. 3 (May 1, 1998): 638–44. http://dx.doi.org/10.1093/jaoac/81.3.638.
Повний текст джерелаАнотація:
abstract Phosphine (PH3) and methyl bromide (ChhBr) are the main fumigants used on stored grains. Published multiresidue methods, including those based on solvent extraction and on purge-and-trap techniques, give poor recoveries of CH3Br and, in our hands, close to zero recovery of PH3 and carbonyl sulfide (COS), a potential fumigant. We examined factors influencing fumigant analysis, including stability of chemicals in leachates and partitioning of fumigant between leachate and air. The partition ratio, defined as the ratio of fumigant concentration in leachate to that in the headspace, varied between 1.1 for PH3 and >100 for ethylene dibromide (EDB). An official procedure involving solvent extraction followed by partitioning was modified by being performed in sealed flasks. This change raised the recovery of ChfoBr from 28 to 85%. Volatile fumigants, including PH3 and COS, were determined from concentrations in the headspace over the leachate (aqueous acidified acetone). Recoveries were nearly quantitative at levels down to 3 ng PH3/g and 16 ng COS/g, provided that fortified samples were used as analytical standards. Thus an existing multifumigant procedure was adapted to enable determination of the main fumigants used on staple foodstuffs.
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Donnelly, Joseph R., Andrew H. Grange, Nelson R. Herron, Gregory R. Nichol, Jeffrey L. Jeter, Richard J. White, William C. Brumley, and Jeanette Van Emon. "Modular Methodology for Determination of Poly chlorinated Biphenyls in Soil as Aroclors and Individual Congeners." Journal of AOAC INTERNATIONAL 79, no. 4 (July 1, 1996): 953–61. http://dx.doi.org/10.1093/jaoac/79.4.953.
Повний текст джерелаАнотація:
Abstract A comprehensive screening and confirmatory method was developed for monitoring polychlorinated biphenyls (PCBs), both as Aroclors and as individual congeners. This approach incorporates extraction, extract cleanup, and analysis modules designed to match cost, time, and data quality requirements. Soxhlet, sonication, supercritical fluid, and accelerated solvent extractions were evaluated. Carbon chromatographic cleanup procedures were used for separation of congeners on the basis of ortho substitutions, which permitted calculation of toxicity equivalents. Individual congener determinations, congener total histograms, and peak comparison techniques for Aroclor identification were elaborated by using high and low resolution mass spectrometricdata. A screening procedure based on immunoassay using the Ohmicron PCB RaPID AssayTM kit gave results comparable to those obtained by gas chromatography with electron capture detection in the range 0.40-230 ppm, when the appropriate Aroclor calibrator was used.
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Shakirah, H. L., Z. N. A. Zulilah, M. S. N. Aniyyah, A. Nabihah, and G. S. Radhiah. "Extraction of Polyhydroxyakanoate (PHA) from Palm Oil Mill Effluent (POME) using Chemical Solvent Extraction." Journal of Physics: Conference Series 1532 (June 2020): 012015. http://dx.doi.org/10.1088/1742-6596/1532/1/012015.
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Moltó,, Juan C., Yolanda Picó,, Jorge Mañes, and Guillermina Font. "Analysis of Polychlorinated Biphenyls in Aqueous Samples Using C18 Glass Column Extraction." Journal of AOAC INTERNATIONAL 75, no. 4 (July 1, 1992): 714–19. http://dx.doi.org/10.1093/jaoac/75.4.714.
Повний текст джерелаАнотація:
Abstract A method for polychlorinated biphenyl (PCB) trace extraction from contaminated water at the part-pertrillion levels is described. This procedure involves quantitative adsorption of PCBs on Cis glass microcolumns. PCBs are retained on the surface and subsequently eluted with n-hexane (5 mL) before gas chromatography. Recovery of water fortified with PCBs was 83.6-108.5%. Compared to liquid-liquid extraction methods, the Cis glass microcolumns give comparable results, lessen solvent costs, and are less time-consuming.
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Bawana, Khaldoon, Qussay Mustafa Yanes, and Mohammed Rasheed. "Gas chromatography determination of the levels of polychlorinated biphenyls (PCBs) in seawater and sediment in the Gulf of Aqaba." Acta Chromatographica 32, no. 2 (June 2020): 117–21. http://dx.doi.org/10.1556/1326.2019.00592.
Повний текст джерелаАнотація:
The levels of persistent organic pollutants, polychlorinated biphenyls (PCBs), were determined in seawater and marine sediments from different sites along the Jordanian coast of the Gulf of Aqaba. Concentrations of 7 PCBs, namely, PCB-28, PCB-52, PCB-101, PCB-118, PCB-138, PCB-153, and PCB-180, were determined. An automated Soxhlet (Soxtec) extraction method was used for extraction with hexane–acetone as a solvent, and a pre-washed multilayer silica gel column was used for the clean-up step. Samples were analyzed using capillary gas chromatography (GC) with an electron capture detector (ECD) and GC–mass spectrometry (GC–MS) for confirmation. The method's limits of detection (LOD) were determined to be from 0.40 to 1.53 ng/L and from 0.39 to 0.91 ng/g dry weight for seawater and sediment, respectively. Concentrations of PCBs in seawater and sediment samples from all sites were below the LOD. This study provides evidence that very low concentrations of PCBs (<2 ng/g) were found in the water and sediments of the Jordanian coast of the Gulf of Aqaba. PCB concentrations measured in this study can be considered as a baseline for future monitoring and control of PCBs as requested by the Stockholm Convention.
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Aramvash, Asieh, Narges Gholami-Banadkuki, Fatemeh Moazzeni-Zavareh, and Samira Hajizadeh-Turchi. "An Environmentally Friendly and Efficient Method for Extraction of PHB Biopolymer with Non-Halogenated Solvents." Journal of Microbiology and Biotechnology 25, no. 11 (November 28, 2015): 1936–43. http://dx.doi.org/10.4014/jmb.1505.05053.
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Pan, Zhong Wei, Jin Huo Lin, Wen Jie Li, Tian Ci Wu, and Jin Ding Pan. "Studies on Extraction Equilibrium of Rare Earths in Ion Liquid Extraction System Using 1-Butyl-3-Methyl-Imidazolium Hexafluorophosphate and 1-Phenyl-3-Methyl-4-Benzoyl-Pyrazolone-5." Advanced Materials Research 602-604 (December 2012): 887–91. http://dx.doi.org/10.4028/www.scientific.net/amr.602-604.887.
Повний текст джерелаАнотація:
The extraction equilibrium of four rare earth ions (REn+, n = 3 or 4) was investigated in ionic liquid (IL) extraction system using 1-butyl-3-methyl-imidazolium hexafluorophosphate ([Bmim]PF6) ionic liquid as extraction solvent and 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP, HP) as extractant. The extraction percentage could be higher than 99%. The extracted species in the REn+-[Bmim]PF6-HP system was neutral REPn (n = 3 or 4) and complete recovery of REn+ extracted into [Bmim]PF6 can be achieved using diluent HCl as stripping agent. [Bmim]PF6 can be recycled in the experiment. The extraction equilibrium constants and the pH1/2 values of four REs and their separation factors between adjacent rare earths were estimated and comparatively studied.
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Abrha, Yirgaalem, and D. Raghavan. "Polychlorinated biphenyl (PCB) recovery from spiked organic matrix using accelerated solvent extraction (ASE) and Soxhlet extraction." Journal of Hazardous Materials 80, no. 1-3 (December 2000): 147–57. http://dx.doi.org/10.1016/s0304-3894(00)00285-5.
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Webb, D. J., B. K. Burnison, A. M. Trimbee, and E. E. Prepas. "Comparison of Chlorophyll a Extractions with Ethanol and Dimethyl Sulfoxide/Acetone, and a Concern about Spectrophotometric Phaeopigment Correction." Canadian Journal of Fisheries and Aquatic Sciences 49, no. 11 (November 1, 1992): 2331–36. http://dx.doi.org/10.1139/f92-256.
Повний текст джерелаАнотація:
Chlorophyll a (Chl a) in water samples from three mesotrophic to eutrophic lakes in north-central Alberta was extracted with one of three solvents (95% ethanol, 90% ethanol, or a 2:3 mixture of dimethyl sulfoxide and 90% acetone (DMSO/acetone)) and analyzed by two techniques (spectrophotometry and high pressure liquid chromatography (HPLC). The dominant phytoplankton were blue-green algae and diatoms. Total Chl a concentrations (i.e. no correction for phaeopigments (Pha)) were not significantly different among solvents (P > 0.5). Total Chl a concentrations from spectrophotometric analyses were significantly higher than those from HPLC analyses (4.2 ± 0.88 and 2.6 ± 0.50 μg∙L−1 respectively, P < 0.05). Pha concentrations derived by spectrophotometry were 64 times higher than those derived by HPLC (1.7 ± 0.52 and 0.025 ± 0.01 μg∙L−1 respectively, P < 0.005). Thus, spectrophotometry appears to dramatically overestimate Pha concentrations and may overestimate total Chl a (i.e. no correction for Pha). Therefore, ethanol and DMSO/acetone are equally suitable for Chl a extraction from natural populations dominated by blue-green algae and/or diatoms, but if information on Pha and/or accessory pigments is required, HPLC analyses are the appropriate route rather than spectrophotometry.
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Jimenez, Leonel R., Wiley A. Hall IV, Matthew S. Rodriquez, William J. Cooper, Jeanette Muhareb, Tom Jones, and Spencer S. Walse. "Quantifying Residues from Postharvest Propylene Oxide Fumigation of Almonds and Walnuts." Journal of AOAC INTERNATIONAL 98, no. 5 (September 1, 2015): 1423–27. http://dx.doi.org/10.5740/jaoacint.14-199.
Повний текст джерелаАнотація:
Abstract A novel analytical approach involving solvent extraction with methyl tert-butyl ether (MTBE) followed by GC was developed to quantify residues that result from the postharvest fumigation of almonds and walnuts with propylene oxide (PPO). Verification and quantification of PPO, propylene chlorohydrin (PCH) [1-chloropropan-2-ol (PCH-1) and 2-chloropropan-1-ol (PCH-2)], and propylene bromohydrin (PBH) [1-bromopropan-2-ol (PBH-1) and 2-bromopropan-1-ol (PBH-2)] was accomplished with a combination of electron impact ionization MS (EIMS), negative ion chemical ionization MS (NCIMS), and electron capture detection (ECD). Respective GC/EIMS LOQs for PPO, PCH-1, PCH-2, PBH-1, and PBH-2 in MTBE extracts were [ppm (μg/g nut)] 0.9, 2.1, 2.5, 30.3, and 50.0 for almonds and 0.8, 2.2, 2.02, 41.6, and 45.7 for walnuts. Relative to GC/EIMS, GC-ECD analyses resulted in no detection of PPO, similar detector responses for PCH isomers, and >100-fold more sensitive detection of PBH isomers. NCIMS did not enhance detection of PBH isomers relative to EIMS and was, respectively, approximately 20-, 5-, and 10-fold less sensitive to PPO, PCH-1, and PCH-2. MTBE extraction efficiencies were >90% for all analytes. The 10-fold concentration of MTBE extracts yielded recoveries of 85–105% for the PBH isomers and a concomitant decrease in LODs and LOQs across detector types. The recoveries of PCH isomers and PPO in the MTBE concentrate were relatively low (approximately 50 to 75%), which confound improvements in LODs and LOQs regardless of detector type.
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Takigami, Hidetaka, Toru Etoh, Tsukasa Nishio, and Shin-ichi Sakai. "Chemical and bioassay monitoring of PCB-contaminated soil remediation using solvent extraction technology." J. Environ. Monit. 10, no. 2 (2008): 198–205. http://dx.doi.org/10.1039/b715474g.
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Schenck, Frank J., Roberta Wagner, Michael K. Hennessy, and Joseph L. Okrasinski. "Screening of Organochlorine Pesticide and Polychlorinated Biphenyl Residues in Nonfatty Seafood Products by Tandem Solid-Phase Extraction Cleanup." Journal of AOAC INTERNATIONAL 77, no. 1 (January 1, 1994): 102–6. http://dx.doi.org/10.1093/jaoac/77.1.102.
Повний текст джерелаАнотація:
Abstract A rapid multiresidue solid-phase extraction (SPE) technique for the isolation and subsequent gas chromatographic (GC) determination of organo-chlorine pesticide and polychlorinated biphenyl (PCB) residues in nonfatty fish, crabmeat, shrimp, and scallops is described. Samples are extracted with acetonitrile, and the extract is subjected to a cleanup using both C18 and Florisil SPE columns. The residues are determined by GC with electron capture detection. Because the injected extracts are free from matrix interferences, the amount of residue present is easily calculated. The average recoveries of 9 spiked (0.01–0.40 ppm) organo-chlorine pesticide residues from 6 different seafood products ranged from 93.8 to 98.4%. The average recoveries of spiked (0.50 ppm) PCB mixtures from 4 different seafood products ranged from 88.5 to 107.2%. This SPE method and the AOAC multiresidue method for organochlorine residues in fish produced comparable results for nonfatty seafood samples containing incurred organochlorine pesticide and PCB residues. The SPE method reduces organic solvent consumption by 95% and hazardous waste by 85% compared with the AOAC method. We were able to carry 10 seafood samples through the extraction and cleanup in less than 2 h by using the SPE method.
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Pan, Zhong Wei, Wen Ting Weng, Hui Bing Yan, Yu Li Yu, Tian Ci Wu, and Jing Ding Pan. "Studies on Temperature Dependent Ionic Liquid Solid-Liquid Extraction Behavior of Rare Earth." Applied Mechanics and Materials 401-403 (September 2013): 817–21. http://dx.doi.org/10.4028/www.scientific.net/amm.401-403.817.
Повний текст джерелаАнотація:
Temperature dependent solid-liquid extraction behavior of eight rare earth elements (REs) was investigated using N-butyl pyridinium hexafluorophosphate ([BPPF6) as an ionic liquid solvent and 8-hydroxyquinoline (HQ) as an extractant at 80 °C. Parameters including the amount of [BPPF6, HQ concentration, extraction time, extraction temperature and pH were investigated and optimized. The extracted species was neutral REQ3 in the RE3+-[BPPF6-HQ solid-liquid extraction system. The extraction percentage of RE3+ could be higher than 99%. The recovery of RE3+ extracted into [BPPF6 can be achieved using the mixture of hydrazine hydrate and ethylenediamine tetraacetic acid as stripping agents. The extraction equilibrium constants and the pH1/2 values of eight REs and their separation factors between adjacent rare earths were estimated and comparatively studied. REs were extracted into solid ionic liquid phase with smaller volume and concentrated to some extent. Furthermore the temperature dependent solid-liquid extraction allows to recover [BPPF6 after the extraction procedures. These results indicate that the proposed procedure can be used for the preconcentration and separation of REs using [BPPF6 with high melting point.
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Haskins, Stacey D., Christina M. Harrison, David G. Kelly, and Ron D. Weir. "Modifications of commercial pressurized solvent extraction (PSE) systems for the analysis of polychlorinated biphenyls in avian whole blood and serum." Canadian Journal of Chemistry 89, no. 1 (January 2011): 77–82. http://dx.doi.org/10.1139/v10-164.
Повний текст джерелаАнотація:
The present study considers simple and cost-effective modifications to commercial pressurised solvent extraction cells to extract polychlorinated biphenyls (PCBs) from avian blood and serum. Blood and serum samples of mass 0.2 g were examined. Such masses are consistent with those which may be obtained from many avian species without sacrificing individuals or compromising breeding and (or) migratory success. Extraction vessels are modified by the use of Teflon inserts, which are readily fabricated at low cost. These inserts reduce internal cell volume and surface area. Thus, background contamination is reduced whilst extraction and rinse solvent is used more effectively to afford a small extract volume. Packing of the cell void with sodium sulfate and florisil achieves in situ sample dehydration and lipid removal. When combined with extraction concentration and large volume injection gas chromatography – ion-trap mass spectrometry (LVI-GC–ITMS), the extraction method is capable of polychlorinated biphenyl analysis without post-extraction clean-up. Validation was accomplished using commercial chicken whole blood and serum, and PCB congeners 28, 77, 105, 126, 153, 167, 170, 180, 183, and 194. Surrogate corrected recoveries in the range of 75% to120% for whole blood and 80% to115% for serum were obtained. Detection limits were in the range of 0.01 to 0.22 ng g–1 for whole blood and 0.03 to 0.45 ng g–1 for serum. The relative standard deviations for all congeners investigated were better than 15%.
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Watupongoh, Cavieta C. A., Defny S. Wewengkang, and Henki Rotinsulu. "AKTIVITAS ANTIMIKROBA DARI EKSTRAK DAN FRAKSI ORGANISME LAUT SPONS Stylissa carteri YANG DIKOLEKSI DARI PERAIRAN SELAT LEMBEH KOTA BITUNG." PHARMACON 8, no. 3 (August 28, 2019): 662. http://dx.doi.org/10.35799/pha.8.2019.29390.
Повний текст джерелаАнотація:
ABSTRACTSponge is a multi-cell marine biota whose tissue and organ functions are very simple. Sponges have considerable potentially in producing active compounds that can be used in the pharmaceutical world. This study aimed to determine the presence of antimicrobial activity from extracts and fractions of the Stylissa carteri Sponge on against the microbes of Staphylococcus aureus, Escherichia coli, and Candida albicans. The extraction process was carried out by maceration using ethanol solvent, and fractionation was carried out using methanol, n-hexane and chloroform solvents. Antimicrobial activity was carried out by disk diffusion agar method. The results showed that the crude ethanol extracts and methanol fractions of the Stylissa carteri sponge actively inhibited the growth of Staphylococcus aureus, Escherichia coli, and Candida albicans microbes. Keywords: Stylissa carteri, antimicrobial, Staphylococcus aureus, Escherichia coli, Candida albicans. ABSTRAKSpons merupakan biota laut multi sel yang fungsi jaringan dan organnya sangat sederhana. Spons memiliki potensi cukup besar dalam menghasilkan senyawa aktif yang dapat digunakan dalam dunia farmasi. Penelitian ini bertujuan untuk menentukan adanya Aktivitas Antimikroba dari ekstrak dan fraksi Spons Stylissa carteri terhadap mikroba Staphylococcus aureus, Escherichia coli, dan Candida albicans. Dilakukan proses ekstraksi dengan cara maserasi terhadap sampel menggunakan pelarut etanol, dan dilakukan fraksinasi menggunakan pelarut metanol, n-heksan dan kloroform. Aktivitas antimikroba dilakukan dengan metode difusi agar. Hasil penelitian menunjukkan bahwa ekstrak kasar dan fraksi metanol dari spons Stylissa carteri aktif menghambat pertumbuhan mikroba Staphylococcus aureus, Escherichia coli, dan Candida albicans. Kata Kunci : Stylissa carteri, antimikroba, Staphylococcus aureus, Escherichia coli, Candida albicans.
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Luo, Jie, Zhao Jie Cui, Shi Yong Du, and Guo Lan Fan. "Temporal Variation and Meteorological Dependence of Polychlorinated Biphenyls in Atmospheric PM10 of Jinan, China." Advanced Materials Research 779-780 (September 2013): 1250–53. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.1250.
Повний текст джерелаАнотація:
s. To explore the PCB pollution characteristics in the airborne particulate matter, seven indicative polychlorinated biphenyls (PCBs) in atmospheric PM10 were determined weekly in Jinan, China. PCB concentrations, profiles, temporal distribution pattern and the correlations between Σ7PCBs and the meteorological conditions were analyzed, aiming to quantify the pollution level of PCBs in urban air. All the samplers were extracted by accelerated solvent extraction (ASE) and analyzed by gas chromatography (GC). The monthly concentrations of Σ7PCBs were 81.4-2335.2 fg/m3. A distinct seasonal variation of PM10-associated PCBs exhibited. Higher concentrations of PCBs in cold weather than warm weather was found. PCB28 and PCB52 were the major components of PM10-associated PCBs in cold weather, while PCB 118 and PCB 180 dominated in warm weather. The fresh emission sources in cold weather, such as the burning of coal for domestic heating, were suggested to be a major influence factor. A significant correlation (p<0.05) was found between the total PCB congeners and atmospheric pressure. Heavy rainfall can also impact PM10-PCBs significantly. The weak correlation coefficient between atmospheric PCBs and wind speed suggested that the inefficient dispersion and no significant pollution sources around.
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Kotel, Marcelinda N., Defny S. Wewengkang, and Herny E. I. Simbala. "POTENSI ANTIMIKROBA DARI EKSTRAK DAN FRAKSI SPONS APLYSINA sp. TERHADAP MIKROBA UJI Escherichia coli, Staphylococcus aureus DAN Candida albicans." PHARMACON 8, no. 2 (May 28, 2019): 268. http://dx.doi.org/10.35799/pha.8.2019.29291.
Повний текст джерелаАнотація:
ABSTRACT Sponge Aplysina sp. is one of the marine biota , which has bioactive compounds that can be used as medicinal ingredients. This study aims to determine the antimicrobial potential of the extracts and fractions of sponge Aplysina sp., against microbes tested of Escherichia coli, Staphylococcus aureus, and Candida albicans. Aplysina sp., sponge was extracted using maceration method with ethanol solvent and fractionated using methanol, n-hexan and chloroform solvents. To test the antimicrobial activity carried out by disk diffusion agar method and observations carried out 24 hours incubation period, with inhibition zones measured using a digital caliper. The results showed that samples of Aplysina sp., proved to have antimicrobial compounds to inhibit Gram –positive bacteria Staphylococcus aureus, and Gram- negative bacteria Escherichia coli, with the highest inhibitory zone activity, and found in Gram –positive Staphylococcus aureus bacteria with measurements of 7,37 mm. Keywords: Sponge Aplysina sp, Antimicrobial, Extraction, Fractionation. ABSTRAK Spons Aplysina sp merupakan salah satu biota laut yang memiliki senyawa bioaktif yang dapat dijadikan sebagai bahan obat. Penelitian ini bertujuan untuk mengetahui potensi antimikroba dari Ekstrak dan Fraksi Spons Aplysina sp Terhadap Mikroba Uji Echerichia coli, Staphylococcus aureus, dan Candida albicans. Spons Aplysina sp diekstraksi menggunakan metode maserasi dengan pelarut etanol dan difraksinasi menggunakan pelarut methanol, n-hexan, dan Kloroform. Untuk pengujian aktivitas antimikroba dilakukan dengan metode difusi agar dan pengamatan dilakukan 1x24 jam masa inkubasi, dengan zona hambat diukur menggunakan digital caliper. Hasil penelitian menunjukkan bahwa sampel Spons Aplysina sp terbukti memiliki senyawa antimikroba untuk menghambat bakteri Gram positif Staphylococcus aureus dan bakteri Gram negatif Echerichia coli, dengan aktivitas zona hambat tertinggi, terdapat pada bakteri Gram positif Staphylococcus aureus dengan hasil pengukuran 7,37 mm. Kata Kunci : Spons Aplysina sp, Antimikroba, Ekstraksi, Fraksinasi.
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Abu-Reidah, Ibrahim M., Amber L. Critch, Charles F. Manful, Amanda Rajakaruna, Natalia P. Vidal, Thu H. Pham, Mumtaz Cheema, and Raymond Thomas. "Effects of pH and Temperature on Water under Pressurized Conditions in the Extraction of Nutraceuticals from Chaga (Inonotus obliquus) Mushroom." Antioxidants 10, no. 8 (August 23, 2021): 1322. http://dx.doi.org/10.3390/antiox10081322.
Повний текст джерелаАнотація:
Currently, there is increased interest in finding appropriate food-grade green extraction systems capable of extracting these bioactive compounds from dietary mushrooms for applications in various food, pharmacological, or nutraceutical formulations. Herein, we evaluated a modified Swiss water process (SWP) method using alkaline and acidic pH at low and high temperature under pressurized conditions as a suitable green food grade solvent to obtained extracts enriched with myco-nutrients (dietary phenolics, total antioxidants (TAA), vitamins, and minerals) from Chaga. Ultra-high performance liquid chromatography coupled to high resolution accurate mass tandem mass spectrometry (UHPLC-HRAMS-MS/MS) was used to assess the phenolic compounds and vitamin levels in the extracts, while inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the mineral contents. Over 20 phenolic compounds were quantitatively evaluated in the extracts and the highest total phenolic content (TPC) and total antioxidant activity (TAA) was observed at pH 11.5 at 100 °C. The most abundant phenolic compounds present in Chaga extracts included phenolic acids such as protocatechuic acid 4-glucoside (0.7–1.08 µg/mL), syringic acid (0.62–1.18 µg/mL), and myricetin (0.68–1.3 µg/mL). Vitamins are being reported for the first time in Chaga. Not only, a strong correlation was found for TPC with TAA (r-0.8, <0.0001), but also, with individual phenolics (i.e., Salicylic acid), lipophilic antioxidant activity (LAA), and total antioxidant minerals (TAM). pH 2.5 at 100 °C treatment shows superior effects in extracting the B vitamins whereas pH 2.5 at 60 and 100 °C treatments were outstanding for extraction of total fat-soluble vitamins. Vitamin E content was the highest for the fat-soluble vitamins in the Chaga extract under acidic pH (2.5) and high temp. (100 °C) and ranges between 50 to 175 µg/100 g Chaga. Antioxidant minerals ranged from 85.94 µg/g (pH7 at 100 °C) to 113.86 µg/g DW (pH2.5 at 100 °C). High temperature 100 °C and a pH of 2.5 or 9.5. The treatment of pH 11.5 at 100 °C was the most useful for recovering phenolics and antioxidants from Chaga including several phenolic compounds reported for the first time in Chaga. SWP is being proposed herein for the first time as a novel, green food-grade solvent system for the extraction of myco-nutrients from Chaga and have potential applications as a suitable approach to extract nutrients from other matrices. Chaga extracts enriched with bioactive myconutrients and antioxidants may be suitable for further use or applications in the food and nutraceutical industries.
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Skrbic, Biljana, Igor Antic, and Ji Yaqin. "Levels and risk assessment of selected persistent organic compounds in dust samples from Tianjin, China." Acta Periodica Technologica, no. 50 (2019): 295–303. http://dx.doi.org/10.2298/apt1950295s.
Повний текст джерелаАнотація:
The aim of this paper was to determine spatial variation of 6 indicator polychlorinated biphenyls (PCBs) and 18 organochlorine pesticides (OCPs) in street dust samples (n=49) collected during summer season from suburban/urban zones of Tianjin, China. Sample preparation was performed by using accelerated solvent extraction with simultaneous extraction and clean-up of PCBs and OCPs, while quantification was carried out using gas chromatography coupled with microelectro absorption detector and gas chromatography coupled with mass spectrometry. The total concentrations of studied PCBs varied from <method limit of quantification (MLOQ) (0.028) to 6.38 ng/g (mean 0.72 ng/g and the median value of 0.028 ng/g), while the total concentrations of studied OCPs varied from <MLOQ (0.020) to 123 ng/g (mean 33.6 ng/g and the median value of 25.9 ng/g). Regarding the OCPs analyzed, dichlorodiphenyltrichloroethanes (DDTs), beta-hexachlorocyclohexane (?-HCH), and ?-HCH were quantified, while all indicator PCBs were quantified at least in one sample, with the exception of PCB 180. Additional, principal component analysis was performed to evaluate relationships between quantified compounds (PCBs, DDTs, and HCHs) and dust characteristics. No correlation was found among quantified compounds and dust characteristics with the exception of PCB 101 and PCB 138, which correlates positively with pH and negatively with conductivity. The total lifetime carcinogenic risk (TLCR) as well as total non-carcinogenic risk hazard quotient (TnHQ) indicated that the risk to the human population related to the presence of OCPs and PCBs in dust samples was acceptable.
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Idris, Shehu, Rashidah Abdul Rahim, and Al-Ashraf Abdullah Amirul. "Bioprospecting and Molecular Identification of Used Transformer Oil-Degrading Bacteria for Bioplastics Production." Microorganisms 10, no. 3 (March 8, 2022): 583. http://dx.doi.org/10.3390/microorganisms10030583.
Повний текст джерелаАнотація:
One of the major impediments to the commercialization of biodegradable plastic is the high cost of substrate. Consequently, there is a continuous search for effective microorganisms and cheaper carbon substrates to reduce the high production cost. In this study, waste transformer oil-degrading bacteria were isolated from soil, wastewater, and sediment samples, using a mineral salt medium (MSM) supplemented with 1% waste transformer oil as the sole carbon source. The isolates were screened for polyhydroxyalkanoates (PHA) production using Nile red staining and fluorescence microscopy. PHA granules accumulation was confirmed using transmission electron microscopy. Oil degradation analysis was accomplished using solvent extraction and gravimetric methods whereas, the bacteria were identified using 16S DNA sequence homology. A total of 62 transformer oil-degrading bacteria were isolated, out of which 16 (26%) showed positive results for Nile red fluorescence microscopy. The identified organisms belong to four different taxonomic genera of Acinetobacter, Bacillus, Proteus, and Serratia. The percentage of oil degradation observed among the different isolates ranged between 19.58% and 57.51%. Analysis of the PHA extracted from the selected isolate revealed the presence of medium chain length polyhydroxyalkanoates (mcl-PHA). The findings of this work have further highlighted the diversity of the bacteria capable of utilizing waste streams such as waste transformer oil. Consequently, the isolates can be explored as agents of converting waste transformer oil into bioplastics.
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Abhilash, Shirin Tabassum, Anirban Ghosh, Pratima Meshram, and Eric D. van Hullebusch. "Microbial Processing of Waste Shredded PCBs for Copper Extraction Cum Separation—Comparing the Efficacy of Bacterial and Fungal Leaching Kinetics and Yields." Metals 11, no. 2 (February 12, 2021): 317. http://dx.doi.org/10.3390/met11020317.
Повний текст джерелаАнотація:
The recycling of electronic scrap is an important subject not only from an environmental aspect but also for recovering metal resources such as copper. In this work, the microbial extraction of copper and other metals (Cu, Ni, Co, Fe and Al) present in the depopulated and shredded printed circuit board (PCB) is elaborated. Bacterial strains of A. ferrooxidans, A. thiooxidans and a fungal strain, A. niger are used for copper extraction along with other metals from shredded PCBs. An optimum metal recovery of 93% Cu was obtained at 308 K, pH 2 using 8% pulp density in 10 days by a mixed culture of A. ferrooxidans and A. thiooxidans. Whereas using A. niger, a metal recovery of 66% Cu was reported using similar experimental conditions. The results show the higher potential ability of bacteria as compared to fungus to bioleach copper. Additionally, the kinetics and mechanism of copper bioleaching from this e-waste by the chemolithotrophs and heterotrophs were evaluated. The leach liquor obtained from the optimized leaching process was subjected to separation and purification of copper as >99% pure copper sulfate using Acorga M5640 by solvent extraction.
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Nasir, Kiran, Rida Batool, and Nazia Jamil. "Scale-Up Studies for Polyhydroxyalkanoate and Halocin Production by <i>Halomonas</i> Sp. as Potential Biomedical Materials." Journal of Biomimetics, Biomaterials and Biomedical Engineering 56 (May 20, 2022): 49–60. http://dx.doi.org/10.4028/p-yqf2wv.
Повний текст джерелаАнотація:
Polyhydroxyalkanoates (PHA) are the biomaterials isolated naturally from bacterial strains. These are present in granules and accumulated intracellularly for storage and energy uptake in stressed conditions. This work was based on the extraction of polyhydroxyalkanoates from haloarchaeal strains isolated from samples of a salt mine and Halocin activity screening of these isolates. For the screening of polyhydroxyalkanoates, Nile Blue and Sudan Black Staining were performed. After confirmation and theoretical determination, polyhydroxyalkanoates extraction was done by sodium hypochlorite digestion and solvent extraction by chloroform method in combination. Polyhydroxyalkanoates production was calculated along with the determination of biomass. Halocin activity of these strains was also screened at different intervals. Isolated strains were identified by 16S RNA gene sequencing. Polyhydroxyalkanoates polymer was produced in form of biofilms and brittle crystals. Halocin activity was exhibited by four strains, among which confirmed halocin activity was shown by strain K7. The remarkable results showed that polyhydroxyalkanoates can replace synthetic plastics which are not environment friendly as they cause environmental pollution – a major threat to Earth rising gradually. Therefore, by switching to the use of biodegradable bioplastics from the use of synthetic plastics, it would be beneficial to the ecosphere.
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Manoppo, Cinlye J., Adithya Yudistira, and Defny S. Wewengkang. "AKTIVITAS ANTIMIKROBA EKSTRAK DAN FRAKSI TUNIKATA (Polycarpa aurata) YANG DIKOLEKSI DI SELAT LEMBEH, BITUNG TERHADAP Escherichia coli, Staphylococcus aureus DAN Candida albicans." PHARMACON 8, no. 1 (February 28, 2019): 243. http://dx.doi.org/10.35799/pha.8.2019.29259.
Повний текст джерелаАнотація:
ABSTRACTTunicate is an invertebrate that lives in a coral reef ecosystem and produces many compounds such as, antibacterial, antitumor and anticancer. This study aimed to determine the antimicrobial activity of extracts and fraction of tunicate (Polycarpa aurata) collected in the Lembeh Strait, Bitung against Escherichia coli, Staphylococcus aureus and Candida albicans. Tunicate (Polycarpa aurata) was extracted by maceration method using 96% ethanol solvent, fractination using liquid-liquid partition method with n-hexane, chloroform and methanol solvent, and antimicrobial testing using Kirby Bauer’s disk diffusion method. The results showed that ethanol extract of tunicate (Polycarpa aurata) had antimicrobial activity againts Escherichia coli with an inhibition of 15.12 mm, and againts Candida albicans with an inhibition of 15 mm. While the methanol fraction showed antimicrobial with a strong category and inhibition of 16.17 mm againts Staphylococcus aureus. Keyword: Tunicate (Polycarpa aurata), Extraction, Fractination, Antimicrobials ABSTRAKTunikata merupakan invertebrata di ekosistem terumbu karang yang banyak menghasilkan senyawa seperti, antibakteri, antitumor dan antikanker. Penelitian ini bertujuan untuk mengetahui aktivitas antimikroba ekstrak dan fraksi tunikata (Polycarpa aurata) yang dikoleksi di Selat lembeh, Bitung terhadap Escherichia coli, Staphylococcus aureus dan Candida albicans. Tunikata (Polycarpa aurata) diekstraksi menggunakan metode maserasi dengan pelarut etanol 96%, fraksinasi menggunakan metode partisi dengan pelarut n-heksan, kloroform dan metanol, dan pengujian antimikroba menggunakan metode difusi agar Kirby Bauer. Hasil penelitian menunjukkan bahwa ekstrak etanol tunikata (Polycarpa aurata) memiliki aktivitas antimikroba kategori kuat pada fraksi metanol dengan daya hambat sebesar 16, 17 mm terhadap Escherichia coli, pada ekstrak etanol dengan daya hambat sebesar 15, 12 mm terhadap Staphylococcus aureus sedangkan pada Candida albicans aktivitas yang sangat baik terjadi pada ektraksi etanol sebesar 15 mm. Kata Kunci: Tunikata (Polycarpa aurata), Ekstraksi dan Fraksinasi, Antimikroba
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Centeno, Carmela R., Carl Renan E. Estrellan, Julius B. Maridable, Leonila C. Abella, and Susan M. Gallardo. "Degradation of Polychlorinated Biphenyls (PCBs) in Water Matrix Using UV/H202 Efect Of Initial PCB Concentration and Analysis of Reaction Product." ASEAN Journal of Chemical Engineering 6, no. 1 (June 1, 2006): 28. http://dx.doi.org/10.22146/ajche.50151.
Повний текст джерелаАнотація:
his study investigated the effect of the different initialconcentrations of polychlorinated biphenyls (PCBs) on its degradation in water matrix using UVIHP2 and on the formation of reaction intermediates or products. Simulated PCB-contaminated water solution was subjected to irradiation with 17 W, 254 nm wavelength UV lamp in a batch tubular reactor. The ratio of oxidant to PCBs, in terms of Arodor 1260, was based on 2,800 I!L HP2 isto 40 ppm PCB. Samples were extracted from the matrix by solid-phase extraction (SPE) method using C18 cartridges with hexane and ethyl acetate as solvents. The samples were analyzed using Gas Chromatography-Electron Capture Detector System (GC-ECD) to determine the concentration of PCBs in the samples and pH was monitored every sampling time. The analysis of chloride (CI-)ion concentration in the samples was done using Argentometric titration. Determination of reaction intermediates and products was carried out with 40 ppm PCB concentration using Gas Chromatography-Mass Spectroscopy (GC-MS) system. A decrease in pH in the early stages of degradation was observed and the higher the initial concentration of PCB the greater was the drop in pH. The PCB degradation profile showed that from 1 to 40 ppm initial concentration, the degradation efficiency of UVIHP2 increased with increasing initial PCB concentration. At 80 ppm, however, it was observed that there was a decrease in the efficiency of the system. The inorganic chloride ions produced indicate that dechlorination took place in the system. GC-MS analysis verified the decrease in concentration of PCBs in the solution and showed the preferential attack of the UV/HP2 to PCBs over long chain saturated alkanes or waxes which contained the PCBs.
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Margaretta, Dewi Liliany, Angliana Chouw, Yanni Dirgantara, Melanie Sadono Djamil, and Ferry Sandra. "Macerated-Pineapple Core Crude Extract-derived Bromelain Has Low Cytotoxic Effect in NIH-3T3 Fibroblast." Indonesian Biomedical Journal 7, no. 2 (August 1, 2015): 101. http://dx.doi.org/10.18585/inabj.v7i2.75.
Повний текст джерелаАнотація:
BACKGROUND: Bromelain is a sulfhydryl proteolytic enzyme that can hydrolyze protein, protease or peptide. Bromelain can be found in pineapple stem, fruit and core. Bromelain is composed of 212 amino acid residues with cysteine-25 forming a polypeptide chain that can hydrolyze peptide bonds by H2O. In medicine, bromelain has been developed as antibiotic, cancer drug, anti-inflammatory agent and immunomodulator. In dentistry, bromelain has potential to reduce plaque formation on the teeth and to irrigate root canal.METHODS: Pineapple core was dried for 3 days to get simplicia. Then simplicia was extracted with water solvent for 24 hours. After that, the macerated-pineapple core crude extract-derived bromelain (PCB) was separated by Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) followed by Coomassie Brilliant Blue (CBB) staining to ensure the presence of bromelain. In cytotoxic test, NIH-3T3 fibroblast cultures were treated with extracts in various concentrations to for 24 or 48 hours. Number of fibroblasts was calculated using 3-(4,5-dimethylthiazol-2- yl)-2,5-Diphenyltetrazolium bromide (MTT) assay.RESULTS: Pineapple core extraction using maceration method produced relative high yield (concentration: 1.5424 g/mL) of bromelain, which was confirmed by CBB staining results with the molecular weight of 33 kDa. Based on cytotoxic test results of PCB on NIH-3T3 fibroblasts, 24-hours-incubation LD50 was 95.7 g/L, while 48-hours-incubation LD50 was 51.1 g/L.CONCLUSION: PCB has low cytotoxic effect in NIH-3T3 fibroblasts.KEYWORDS: bromelain, pineapple, extract, cytotoxic, MTT
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Liu, Tengfei, Ying Song, Xiangyun Wang, Linlin Shi, and Minghui Dong. "A Facile and Rapid Strategy for Quantifying PCBs in Cereals Based on Dispersive Solid-Phase Extraction and Gas Chromatography–Mass Spectrometry: A Reference for Safety Concerns in Sustainable Textiles." Materials 16, no. 4 (February 17, 2023): 1698. http://dx.doi.org/10.3390/ma16041698.
Повний текст джерелаАнотація:
Cereals and their derivative products such as starch and cyclodextrin are significant natural materials for sustainable textile processing (e.g., sizing, dispersing, etc.). However, the contamination of cereals with polychlorinated biphenyls (PCBs) is often neglected, which has led to increasing concerns due to the adverse effects on end users. Therefore, monitoring PCBs in cereals is of great importance in preventing health risks. However, high starch, protein, and fat contents make cereals a complicated matrix and can challenge the analysis of PCBs in cereals. This work describes a facile and rapid strategy for quantifying 18 PCBs in cereals that included corn, wheat, and rice through dispersive solid-phase extraction and gas chromatography with mass spectrometry. Importantly, this was the first time that carboxyl-modified, multi-walled carbon nanotubes were incorporated in the detection of PCBs in cereals. The influences of several parameters on the extraction and clean-up efficiency were investigated; these included the type and volume of extraction solvent, sonication time, and the type and dosage of the adsorbent. The matrix effects on quantification were also evaluated. This approach exhibited a better clean-up performance. All the analytes showed weak matrix effects, and thus a solvent standard plot could be prepared for their quantification. Spiking experiments in the selected matrices at three concentration levels from 0.5 to 10 μg/kg resulted in satisfactory recoveries that ranged from 79.2% to 110.5% with relative standard deviations (RSDs; n = 6) less than 10.3%. The limits of detection (LODs) and quantification (LOQs) ranged from 0.04 to 0.1 μg/kg and 0.1 to 0.4 μg/kg, respectively. The practical application of this method was investigated by analyzing actual cereal samples, which demonstrated that the proposed approach was a facile and efficient strategy for PCB determination and provided a reference for the safety evaluation of sustainable textiles. The method also could be generalized to other troublesome samples for testing of multiple PCBs.
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Lewiński, Radosław, Agnieszka Hernik, Monika Liszewska, Brian Buckley, Katarzyna Czaja, Wojciech Korcz, Anna Słomczyńska, and Paweł Struciński. "Validation of a Modified QuEChERS Method for the Determination of Selected Organochlorine Compounds in Honey." Molecules 28, no. 2 (January 14, 2023): 842. http://dx.doi.org/10.3390/molecules28020842.
Повний текст джерелаАнотація:
Honey is considered to be a health-promoting food product. Therefore, it is assumed that it should be free of contaminants. Although the use of organochlorine pesticides (OCPs) was banned a few decades ago in developed countries, persistent organic pollutants (POPs) are still detected in various environmental and biological matrices, including food. These contaminants exhibit toxic properties and bioaccumulate in some food chains. The validation of a modified QuEChERS extraction method was successfully performed for o,p’-DDT, o,p’-DDE, o,p’-DDD, p,p’-DDT, p,p’-DDE, p,p’-DDD, heptachlor and dieldrin. 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB 153) was used as an internal standard. The modification involved changing the solvent from acetonitrile to n-hexane after extraction. Quantitation was carried out using gas chromatography with an electron capture detector (µECD). The mean recovery values for o,p’-DDT, o,p’-DDE, o,p’-DDD, p,p’-DDT, p,p’-DDE, p,p’-DDD and dieldrin, spiked at 2.9 ng/g and 20 ng/g, ranged from 64.7% to 129.3%, and, for heptachlor spiked at 5.6 ng/g and 20 ng/g, ranged from 68.0% to 88.3%. The relative standard deviation (RSD) for these concentrations did not exceed 20%, and the within-laboratory reproducibility was below 20%, except o,p’-DDE and p,p’-DDT, which were 25.2% and 20.7%, respectively. This modified QuEChERS extraction method for selected organochlorine compounds was demonstrated as effective for routine testing in honey.
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Reddy, V. Uttej Nandan, S. V. Ramanaiah, M. Venkateswar Reddy, and Young-Cheol Chang. "Review of the Developments of Bacterial Medium-Chain-Length Polyhydroxyalkanoates (mcl-PHAs)." Bioengineering 9, no. 5 (May 21, 2022): 225. http://dx.doi.org/10.3390/bioengineering9050225.
Повний текст джерелаАнотація:
Synthetic plastics derived from fossil fuels—such as polyethylene, polypropylene, polyvinyl chloride, and polystyrene—are non-degradable. A large amount of plastic waste enters landfills and pollutes the environment. Hence, there is an urgent need to produce biodegradable plastics such as polyhydroxyalkanoates (PHAs). PHAs have garnered increasing interest as replaceable materials to conventional plastics due to their broad applicability in various purposes such as food packaging, agriculture, tissue-engineering scaffolds, and drug delivery. Based on the chain length of 3-hydroxyalkanoate repeat units, there are three types PHAs, i.e., short-chain-length (scl-PHAs, 4 to 5 carbon atoms), medium-chain-length (mcl-PHAs, 6 to 14 carbon atoms), and long-chain-length (lcl-PHAs, more than 14 carbon atoms). Previous reviews discussed the recent developments in scl-PHAs, but there are limited reviews specifically focused on the developments of mcl-PHAs. Hence, this review focused on the mcl-PHA production, using various carbon (organic/inorganic) sources and at different operation modes (continuous, batch, fed-batch, and high-cell density). This review also focused on recent developments on extraction methods of mcl-PHAs (solvent, non-solvent, enzymatic, ultrasound); physical/thermal properties (Mw, Mn, PDI, Tm, Tg, and crystallinity); applications in various fields; and their production at pilot and industrial scales in Asia, Europe, North America, and South America.
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Koller, Martin, Rodolfo Bona, Emo Chiellini, and Gerhart Braunegg. "Extraction of short-chain-length poly-[(R)-hydroxyalkanoates] (scl-PHA) by the “anti-solvent” acetone under elevated temperature and pressure." Biotechnology Letters 35, no. 7 (March 24, 2013): 1023–28. http://dx.doi.org/10.1007/s10529-013-1185-7.
Повний текст джерела
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Lonteng, Elur, Adithya Yudistira, and Defny S. Wewengkang. "UJI AKTIVITAS ANTIOKSIDAN EKSTRAK KARANG LUNAK Klyxum Sp YANG DIKOLEKSI DARI DESA TUMBAK KECAMATAN POSUMAEN MINAHASA TENGGARA." PHARMACON 9, no. 2 (May 28, 2020): 205. http://dx.doi.org/10.35799/pha.9.2020.29272.
Повний текст джерелаАнотація:
ABSTRACT Soft Coral Klyxum sp.. is a rich sources in bioactive compounds such as terpenoids, steroids, and steroid glycosides which are commonly used in the health sector. The purpose of this study was to determine the activity of antioxidant compounds from ethanol extracts of Klyxum sp. Klyxum sp., was extracted by maceration using ethanol as a solvent. As a parameter, testing of antioxidant activity was carried out using the DPPH (1,1-diphenil-2-picrylhydarzyl) method, which was measured using UV-Vis spectrophotometry at a wavelength of 517 nm. The results showed that the ethanol extracts of soft coral Klyxum sp., proven to have antioxidant activity in each concentration test. Keywords: Klyxum sp. Soft Coral, Antioxidants, Extraction, DPPH ABSTRAK Karang Lunak Klyxum sp. merupakan sumber yang kaya akan senyawa bioaktif seperti terpenoid, steroid, dan steroid glikosida yang biasa dimanfaatkan dalam dibidang kesehatan. Tujuan dari penelitian ini yaitu, untuk mengetahui aktivitas senyawa antioksidan dari ekstrak etanol Karang Lunak Klyxum sp. Karang Lunak Klyxum sp. diekstraksi menggunakan metode maserasi dengan etanol sebagai pelarut. Sebagai parameter, pengujian aktivitas antioksidan dilakukan dengan metode DPPH (1,1-diphenil-2-picrylhydarzyl) yang diukur menggunakan Spektrofotometri UV-Vis pada panjang gelombang 517 nm. Hasil penelitian menunjukkan ekstrak etanol Karang Lunak Klyxum sp. terbukti memiliki aktivitas antioksidan disetiap konsentrasi pengujian. Kata Kunci : Karang Lunak Klyxum sp., Antioksidan, Ekstraksi, DPPH
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Rumangu, Afrilia Veronika, Adithya Yudistira, and Henki Rotinsulu. "UJI AKTIVITAS ANTIOKSIDAN DARI EKSTRAK ETANOL BUNGA KANA MERAH (Canna coccinea Mill) MENGGUNAKAN METODE DPPH." PHARMACON 8, no. 3 (August 28, 2019): 542. http://dx.doi.org/10.35799/pha.8.2019.29328.
Повний текст джерелаАнотація:
Cana plants are flower ornamental plants whose genus or margins are the only ones in the family Cannacea. This study aims to determine the activity of antioxidant compounds from ethanol extract of Canna coccinea Mill flower. by using the DPPH method. Flowers Canna coccinea Mill extracted using maceration with ethanol as a solvent. As a parameter, testing of antioxidant activity was carried out using the DPPH (1,1 – diphenyl-2-pikrilhidrazil) method which was measured using UV-Vis Spectrophotometry at a wavelength of 517nm. The result showed that ethanol of Canna coccinea Mill,flower proven to have antioxidant activity in each concentration test. The highest concentration has an free radical scavenging activity by reaching of 56,00%.Keywords: Flowers Canna coccinea Mill, Antioxidant, Extraction, DPPH ABSTRAKTanaman kana adalah tanaman hias bunga yang genus atau marganya merupakan satu-satunya dalam family Cannaceae. Penelitian ini bertujuan untuk mengetahui aktivitas senyawa antioksidan dari ekstrak etanol bunga Canna coccinea Mill. dengan menggunakan metode DPPH. Bunga Canna coccinea Mill. diekstraksi menggunakan metode maserasi dengan etanol sebagai pelarut. Sebagai parameter, pengujian aktivitas antioksidan dilakukan dengan metode DPPH (1,1-difenil-2-pikrilhidrazil) yang diukur menggunakan Spektrofotometri UV-Vis pada panjang gelombang 517 nm. Hasil penelitian menunjukkan ekstrak etanol bunga Canna coccinea Mill. terbukti memiliki aktivitas antioksidan disetiap konsentrasi pengujian. Konsentrasi tertinggi memiliki aktivitas penangkal radikal bebas dengan mencapai presentase 56,00%.Kata Kunci : Bunga Canna coccinea Mill, Antioksidan, Ekstraksi, DPPH
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Runtuwene, Kristianus, Paulina V. Y. Yamlean, and Adithya Yudistira. "FORMULASI,UJI STABILITAS DAN UJI EFEKTIVITAS ANTIOKSIDAN SEDIAAN GEL DARI EKSTRAK ETANOL DAUN SESEWANUA (Clerodendron squamatum Vahl) DENGAN MENGGUNAKAN METODE DPPH." PHARMACON 8, no. 2 (May 28, 2019): 298. http://dx.doi.org/10.35799/pha.8.2019.29295.
Повний текст джерелаАнотація:
ABSTRACTChronic exposure to UV radiation on the skin can cause many side effects on the skin such as premature aging, skin cancer and decreased ability of the immune response. Irreversible skin aging begins at the age of 20 years. Mature leaves (Clerodendron squamatumVahl) have flavonoids, which are antioxidant compounds. This study aims to prove that seswanua leaf gel preparations have good stability, meet the requirements of gel preparations and have good antioxidant effectiveness. This type of research is descriptive analytics. Extraction of sesewanua leaves was carried out using maceration with 96% ethanol solvents. Evaluation of gel preparations was carried out by conducting homogeneity, organoleptic, pH, dispersion and adhesion test. Gel stability test was carried out using the cycling test method. Testing the effectiveness of antioxidants using the method (1,1-diphenyl-2-picrylhydrazyl (DPPH) with IC50 results of 123 mg / L for storage and 263 mg / L for post-storage. It can be concluded that gel preparations with 3% HPMC concentration have good stability, fulfills the requirements of gel preparations and has antioxidant effectivenessKeywords : Sesewanua Leaves, Extraction, Gel Preparation, AntioxidantsABSTRAKPaparan kronis radiasi UV terhadap kulit dapat menimbulkan banyak efek samping pada kulit seperti penuaan dini, kanker kulit dan penurunan kemampuan respon imun. Penuaan kulit yang bersifat irreversible dimulai pada usia 20 tahun. Daun Sesewanua (Clerodendron squamatum Vahl) memiliki senyawa flavonoid yang bersifat sebagai senyawa antioksidan. Penelitian ini bertujuan untuk membuktikan sediaan gel daun sesewanua mempunyai stabilitas yang baik, memenuhi persyaratan sediaan gel dan mempunyai efektivitas antioksidan yang bagus.Jenis penelitian ini ialah Deskriptif Analitik. Ekstraksi daun sesewanua dilakukan dengan menggunakan metode maserasi danpelarut etanol 96% . Evaluasi sediaan gel dilakukan dengan melakuan uji homogenitas, organoleptis, pH, daya sebar dan daya lekat. Uji stabilitas gel dilakukan dengan menggunakan metode cycling test. Pengujian efektivitas antioksidan menggunakan metode (1,1-difenil-2-pikrilhidrazil (DPPH)dengan hasil IC50 sebesar 123 mg/L untuk sebelum penyimpanan dan 263 mg/L untuk sesudah penyimpanan.. Sehingga dapat disimpulkan sediaan gel dengan konsentrasi HPMC 3% mempunyai stabilitas yang baik, memenuhi persyaratan sediaan gel dan memiliki efektivitas antioksidan Kata Kunci : Daun Sesewanua, Ekstraksi, Sediaan Gel, Antioksidan
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Metcalfe-Smith, Janice L., R. James Maguire, and Suzanne P. Batchelor. "Polychlorinated Biphenyl Congeners and Chlorinated Pesticides in Fish from the Yamaska River Basin, Quebec." Water Quality Research Journal 30, no. 2 (May 1, 1995): 179–204. http://dx.doi.org/10.2166/wqrj.1995.021.
Повний текст джерелаАнотація:
Abstract Bottom-feeding fish from the Yamaska River in Quebec and its major tributary, the Noire River (5 female specimens from each site), were analyzed for residues of organochlorine pesticides and PCB congeners in liver, spleen, gonad, kidney, gall bladder, visceral fat and dorsal muscle. Significant quantities of target chemicals were found in the basic extracts as well as the acidic extracts of these fish tissues, suggesting that acidic digestion followed by saponification and extraction with an organic solvent may provide a more complete recovery of organic contaminants residues from biological tissues than conventional techniques. Residues were highest and least variable in fat, therefore this tissue was used to compare patterns of contamination between sites. Fish from the Noire River contained 6X as much ZDDT and 3X as much ZPCBs in their fat than fish from the Yamaska River (2800 versus 440 ng/g and 1700 versus 500 ng/g wet weight, respectively), but no differences between sites were observed for dieldrin, lindane or heptachlor epoxide. Noire River fish exhibited a less degraded pattern of PCB contamination, with proportionately more penta- (15% versus 4%) and less hexa- and heptachlorobiphenyls (70% versus 81%) plus nine more congeners in their fat. They also contained a higher proportion of the toxic congeners (28% versus 17%), had lower lipid contents and were in poorer condition. Thus, further investigation of the sources and effects of persistent organic contaminants in the Noire River basin may be warranted.