Journal articles: 'Hydrolysis conditions'

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Thanh Ngoc, Nguyen Thi. "OPTIMIZATION FOR BATCH PROTEOLYTIC HYDROLYSIS OF SPENT BREWER’S YEAST BY USING PROTEASES." Vietnam Journal of Science and Technology 54, no. 4A (March 21, 2018): 181. http://dx.doi.org/10.15625/2525-2518/54/4a/11992.

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The yield of proteolylic hydrolysis for spent brewer’s yeast by protease and aminoacid contents of hydrolysates (the main factors influencing in taste of hydrolysed product) depends on factors influencing in catalytic activities of enzymes as temperature, pH value, type of used enzymes and ratio enzyme/substrate. With the purpose to hydrolyse the spent brewer’s yeast for food application, bitterness of hydrolysate takes the firth consideration, and than the yield of hydrolysing process plays economic role. In this paper, it is dealt with determination of optimal conditions to obtain the highest yield of hydrolysis process and the lowest bitterness of hydrolysate (the bitterness is determined by sensory evaluation, expressed equivalently with concentration of quinine). Response surface methodology (RSM) was used to determine optimum condition for batch proteolytic hydrolysis of spent brewer’s yeast. The influencing factors were investigated as temperature (X1): 40 oC–60 oC; pH (X2): 6.0–9.0, ratio E (flavourzyme)/S (X3): 5–10 U/g and hydrolysis time (X4): 6–9 hours. The experimental responses including degree of hydrolysis (Y1) (%) and bitterness of hydrolysate (Y2) (μmol quinine/ml) are performed in second-degree model. The optimal conditions for obtaining high degree of hydrolysis and low bitterness are determined: Ratio of enzyme mixture (alcalase 7.5 U/g and flavourzyme 8.5 U/g), pH 7.5, hydrolysis temperature at 52oC and hydrolysis time 9 hours. Under the optimal conditions, the actual values obtained for the yield of hydrolysis was 40.81 ± 0.044 % and the bitterness equivalently with concentration of quinine was 16.37 ± 0.03 μmol quinine/ml.

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Lisak Jakopović, Katarina, Seronei Chelulei Cheison, Ulrich Kulozik, and Rajka Božanić. "Comparison of selective hydrolysis of α-lactalbumin by acid Protease A and Protease M as alternative to pepsin: potential for β-lactoglobulin purification in whey proteins." Journal of Dairy Research 86, no. 1 (February 2019): 114–19. http://dx.doi.org/10.1017/s0022029919000086.

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AbstractThe experiments reported in this research paper examine the potential of digestion using acidic enzymes Protease A and Protease M to selectively hydrolyse α-lactalbumin (α-La) whilst leaving β-lactoglobulin (β-Lg) relatively intact. Both enzymes were compared with pepsin hydrolysis since its selectivity to different whey proteins is known. Analysis of the hydrolysis environment showed that the pH and temperature play a significant role in determining the best conditions for achievement of hydrolysis, irrespective of which enzyme was used. Whey protein isolate (WPI) was hydrolysed using pepsin, Acid Protease A and Protease M by randomized hydrolysis conditions. Reversed-phase high performance liquid chromatography was used to analyse residual proteins. Regarding enzyme selectivity under various milieu conditions, all three enzymes showed similarities in the reaction progress and their potential for β-Lg isolation.

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Egyed, J., and R. E. Oakey. "Hydrolysis of deoxycorticosterone-21-yl sulphate and dehydroepiandrosterone sulphate by microsomal preparations of human placentae: evidence for a common enzyme." Journal of Endocrinology 106, no. 3 (September 1985): 295–301. http://dx.doi.org/10.1677/joe.0.1060295.

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ABSTRACT The human placenta can hydrolyse both dehydroepiandrosterone-3β-yl sulphate (DHASO4−) and deoxycorticosterone-21-yl sulphate (DOCSO4−). There is some uncertainty as to whether the same or different enzymes are responsible for hydrolysis of these substrates. As a fresh approach to this problem we have compared the quantities of DHASO4− and DOCSO4− hydrolysed by microsomal preparations of placentae obtained from 14 normal pregnancies and from 14 pregnancies complicated by steroid sulphatase deficiency. Under the conditions used, and standardizing the results to unit time and quantity of protein, 1380–8830 fmol DHASO4− were hydrolysed by 14 normal placentae whereas < 1000 fmol DHASO4− were hydrolysed by the other 14 placentae, thereby designated as steroid sulphatase deficient. Net hydrolysis of DOCSO4− by the preparations of normal tissue was 9–52 fmol; hydrolysis of this substrate by steroid sulphatase-deficient tissues was indistinguishable from that by boiled tissue (< 29 fmol). Thus preparations of placentae which hydrolysed DHASO4− also hydrolysed DOCSO4− ; tissues which did not hydrolyse DHASO4− also failed to hydrolyse DOCSO4−. The quantities of DHASO4− and DOCSO4− hydrolysed by the 28 individual placentae showed a positive correlation (r = 0·91, P < 0·001). The apparent Michaelis constants for hydrolysis of DHASO4− and DOCSO4− were 38 and 274 μmol/l respectively. These results are consistent with the proposal that these substrates are hydrolysed by a common enzyme. J. Endocr. (1985) 106, 295–301

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CAMACHO, FERNANDO, PEDRO GONZÁLEZ-TELLO, MARÍA-PURIFICACIÓN PÁEZ-DUEÑAS, EMILIA-MARÍA GUADIX, and ANTONIO GUADIX. "Correlation of base consumption with the degree of hydrolysis in enzymic protein hydrolysis." Journal of Dairy Research 68, no. 2 (May 2001): 251–65. http://dx.doi.org/10.1017/s0022029901004824.

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It is fairly easy to control the enzymic hydrolysis of proteins in alkaline conditions by measuring the base consumption required to keep the pH constant in the reactor. Unfortunately, however, base consumption is not related in any simple way to the degree of hydrolysis reached at any given moment and to establish this relationship it is essential to find out the mean pK of the α-amino groups released during the hydrolytic process. We have shown here that the correct mean pK value varies according to the pH of the working conditions and that the relationship between these values may depend upon the kind of protein and protease used. We have put forward a method for determining this relationship experimentally by using a given protein–protease system, consisting of an alkaline titration of the raw protein and when partially hydrolysed. We have tested the results predicted by our theoretical model by applying it to the hydrolysis of whey proteins with a bacterial protease from Bacillus licheniformis at 50 °C, pH 8·0. This model can easily be applied to any hydrolytic process involving the appearance of functional groups that are partially protonizable under the working conditions in question in order to follow the kinetics of the reaction via the consumption of the neutralizing agent required to keep pH constant.

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Chatterjee, T., B. K. Chatterjee, and D. K. Bhattacharyya. "Study of lipase-catalyzed hydrolysis of some monoterpene esters." Canadian Journal of Microbiology 47, no. 5 (May 1, 2001): 397–403. http://dx.doi.org/10.1139/w01-026.

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Studies of the hydrolysis of bornyl, citronellyl, geranyl, and terpenyl acetates by commercially available lipases of Candida rugosa, Rhizopus arrhizus, and Mucor miehei are presented. The hydrolysis of these monoterpene esters is investigated at various temperatures and pHs, and the time dependence of the percentage of esters hydrolysed is studied. The catalytic activities of the lipases in hydrolysing the esters are compared and, overall, it is observed that under the experimental conditions used the nonspecific lipase from C. rugosa produces the highest yields of the monoterpene alcohols in comparison to the primary-ester specific lipases such as R. arrhizus and M. miehei. A rate kinetic model has been used to understand the time dependence of the yield of the product acid.Key words: enzymatic hydrolysis, kinetics, lipase, monoterpene esters.

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Jonsson, S., V. A. Vavilin, and B. H. Svensson. "Phthalate hydrolysis under landfill conditions." Water Science and Technology 53, no. 8 (April 1, 2006): 119–27. http://dx.doi.org/10.2166/wst.2006.242.

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Experimental data from a study using a landfill simulation reactor were used to develop and calibrate a one-dimensional distributed model of co-digestion of municipal solid waste and three phthalic acid diesters with different water solubilities. The three diesters were diethyl phthalate, dibutyl phthalate, and di-2-ethylhexyl phthalate. Two types of municipal solid wastes were assumed, easily degradable and recalcitrant. The model considered inhibition of hydrolysis of the recalcitrant fraction and phthalic acid esters, and also methanogenesis at acidic pH. The results indicated that the prolonged steady-state concentrations of the diesters in the leachates could be explained by equilibrium between physicochemical desorption and sorption processes for the three diesters. When methanogenic conditions were induced in the acidogenic landfill simulation reactor, inhibition of both hydrolysis of recalcitrant MSW and of phthalic acid esters ceased.

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Goel, Rajeev, Takashi Mino, Hiroyasu Satoh, and Tomonori Matsuo. "Comparison of hydrolytic enzyme systems in pure culture and activated sludge under different electron acceptor conditions." Water Science and Technology 37, no. 4-5 (February 1, 1998): 335–43. http://dx.doi.org/10.2166/wst.1998.0659.

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Enzymatic hydrolysis under different electron acceptor conditions in nutrient removal activated sludge treatment processes is a weak link in the Activated Sludge Model no. 2 (Henze et al., 1995). An experimental study was undertaken to gain insight into the hydrolysis process with specific focus on hydrolysis kinetics and rates under different electron acceptor conditions. Two pure cultures, Bacillus amyloliquefaciens (Gram positive) and Pseudomonas saccharophila (Gram negative) were chosen for the study. In addition, activated sludge grown in an anaerobic-aerobic system was tested for enzymatic activity using starch as the model substrate. The hydrolytic enzymes were found to be released into the bulk in pure cultures whereas the enzyme activity was found to be mainly associated with the cell surfaces in activated sludge. Further, it was observed that the development of the hydrolytic enzyme system in Bacillus amyloliquefaciens and P. saccharophila is strongly suppressed under anoxic and anaerobic conditions. However, the effect of anaerobic and aerobic incubation on hydrolytic enzyme activity in activated sludge was found to be small. Starch hydrolysis kinetic data from batch experiments with activated sludge followed substrate saturation kinetics that were linear with biomass concentration. Finally, the similar hydrolytic enzyme activities observed under anaerobic and aerobic phases of a sequencing batch reactor are explained by considering the aspects of enzyme location and enzyme system development under aerobic and anaerobic phases. It is proposed that the floc bound enzymes are recycled in a single sludge system so that an equilibrium exists between enzyme loss and synthesis at steady state.

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Kleekayai, Thanyaporn, Aurélien V. Le Gouic, Barbara Deracinois, Benoit Cudennec, and Richard J. FitzGerald. "In Vitro Characterisation of the Antioxidative Properties of Whey Protein Hydrolysates Generated under pH- and Non pH-Controlled Conditions." Foods 9, no. 5 (May 5, 2020): 582. http://dx.doi.org/10.3390/foods9050582.

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Bovine whey protein concentrate (WPC) was hydrolysed under pH-stat (ST) and non pH-controlled (free-fall, FF) conditions using Debitrase (DBT) and FlavorPro Whey (FPW). The resultant whey protein hydrolysates (WPHs) were assessed for the impact of hydrolysis conditions on the physicochemical and the in vitro antioxidant and intracellular reactive oxygen species (ROS) generation in oxidatively stressed HepG2 cells. Enzyme and hydrolysis condition dependent differences in the physicochemical properties of the hydrolysates were observed, however, the extent of hydrolysis was similar under ST and FF conditions. Significantly higher (p < 0.05) in vitro and cellular antioxidant activities were observed for the DBT compared to the FPW–WPHs. The WPHs generated under ST conditions displayed significantly higher (p < 0.05) oxygen radical absorbance capacity (ORAC) and Trolox equivalent antioxidant capacity (TEAC) values compared to the FF-WPHs. The impact of hydrolysis conditions was more pronounced in the in vitro compared to the cellular antioxidant assay. WPH peptide profiles (LC-MS/MS) were also enzyme and hydrolysis conditions dependent as illustrated in the case of β-lactoglobulin. Therefore, variation in the profiles of the peptides released may explain the observed differences in the antioxidant activity. Targeted generation of antioxidant hydrolysates needs to consider the hydrolysis conditions and the antioxidant assessment method employed.

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9

Thanh Ngoc, Nguyen Thi. "INFLUENCES OF TECHOLOGICAL HYDROLYSIS CONDITION ON NUCLEIC ACID CONTENT OF SPENT BREWER’S YEAST HYDROLYSATE." Vietnam Journal of Science and Technology 55, no. 5A (March 24, 2018): 169. http://dx.doi.org/10.15625/2525-2518/55/5a/12192.

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Currently, with the strong increasing of the brewing industry output, the consequencing amount of yeast residue is very large. Utilizing a large source of protein from brewers yeast to produce hydrolysed products using protease as food and food additives has a high real-life benefit. However, one limitation in the use of yeast and hydrolysis products is that the amount of nucleic acid in the yeast in particular and in the microbial cells is generally high. Nucleic acid is abundant in food that causes gout in humans and animals. There are many methods for reducing or separating nucleic acids in hydrolysed products such as extracellular ribonuclease enzymes, chemical agents, thermal shock and autolysis. Use extracellular ribonuclease enzyme for hydrolysis of nucleic acid gives good efficiency, but with high production cost. Chemical agents affect the quality of the hydrolysed products used in the food industry. There have been many good-efficiency studies using heat shock and autolysis to reduce the amount of nucleic acid in the hydrolysate. However, no research has been conducted to reduce the amount of nucleic acid by hydrolysis techniques. In this paper, we investigated the effects of heat shock, autolysis and hydrolysis techniques (batch, continuous overflow and continuous circulation) of brewery yeast protein to nucleic acid content in yeast hydrolysate. The results showed that the content of nucleic acid in the hydrolysate (with a concentration of 55 % dry matter) was the smallest. Under normal hydrolysis conditions, the nucleic acid content was 8.7 g / kg and when there was a heat shock+ autolysis, it decreased to 6.34 g/kg. After optimizing the hydrolysis conditions, the nucleic acid content of the hydrolysate was reduced to 5.41g/kg on continuous hydrolysis system.

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Margolis, Sam A., Lois Jassie, and H. M. Kingston. "The hydrolysis of proteins by microwave energy." Journal of Automatic Chemistry 13, no. 3 (1991): 93–95. http://dx.doi.org/10.1155/s1463924691000172.

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Microwave energy, at manually-adjusted, partial power settings has been used to hydrolyse bovine serum albumin at 125 °C. Hydrolysis was complete within 2 h, except for valine and isoleucine which were completely liberated within 4 h. The aminoacid destruction was less than that observed at similar hydrolysis conditions with other methods and complete hydrolysis was achieved more rapidly. These results provide a basis for automating the process of amino-acid hydrolysis.

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Zhu, Zhen, Da Peng Wang, Yuan Ma, Xu Yang, Xiao Juan Wang, Hua Yin, and Yan An. "Optimization of Antioxidant Silk Fibroin Peptide Hydrolysis Process." Advanced Materials Research 1073-1076 (December 2014): 1789–92. http://dx.doi.org/10.4028/www.scientific.net/amr.1073-1076.1789.

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Papain, pancreatin, pepsin, rypsin, neutral protease were used for the enzymatic hydrolysis of silk fibroin solution. It was found that the silk fibroin peptides after hydrolysis by pancreatin exhibited the strongest antioxidant activity, in comparison of five hydrolysed solutions by the pyrogallol method. The pancreatin hydrolysis process was then optimised. The optimum conditions of pancreatin hydrolysis antioxidant activity silk fibroin peptide was determined by orthogonal experiment: reaction time 160min, enzyme concentration 4%,substrate concentration 20mg/ml, pH 8, temperature 38°C. The best hydrolysis under the hydrolyzate on superoxide radical scavenging rate of 72.73%.

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Ying, Ma, Lin Li, and Sun Da-Wen. "Preparation of high Fischer ratio oligopeptide by proteolysis of corn gluten meal." Czech Journal of Food Sciences 26, No. 1 (February 19, 2008): 38–47. http://dx.doi.org/10.17221/1138-cjfs.

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A method to obtain an oligopeptide with high Fischer ratio is described. Corn gluten meal (CGM) was hydrolysed with Alcalase 2.4L using a two-step hydrolysis. In the first-step hydrolysis, the enzyme reaction conditions for hydrolysing CGM were optimised by using the orthogonal experimental design, while pH = 8.0, temperature = 55°C, enzyme to substrate ratio (3:97, w/w), and the substrate concentration = 5% were identified as the optimum conditions, under which up to 11.62% degree of hydrolysis (DH) could be obtained. The hydrolysate was then fractionated by ultrafiltration using a membrane with the molecular cutoff of over 10 kD at 20 kPa. For the second-step hydrolysis, the filtrate was adjusted to pH 6.0, then papain was added at 50°C and the mixture was maintained for 3 hours. The hydrolysate was obtained after inactivating papain and centrifuging. Then the salt (mainly NaCl) in the hydrolysate was removed with an ion exchange resin at the speed of 8 times bed volume per hour, and aromatic amino acids were removed through absorption by active carbon. By using Sephadex G-25 gel filtration chromatography, a peptide mixture with low molecular weights between 1000 and 1300 was obtained. Finally, tests on amino acid composition and free amino acid concentration of oligopeptide solution showed that the oligopeptide had a high Fischer ratio of 34.71 and the yield of 11.59%.

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Ngoc, Nguyen Thi Thanh, Quan Le Ha, and Dinh Van Thuan. "Optimization for continuous overflow proteolytic hydrolysis of spent brewer’s yeast by using proteases." Vietnam Journal of Biotechnology 14, no. 4 (April 19, 2018): 735–42. http://dx.doi.org/10.15625/1811-4989/14/4/12308.

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A large amount of spent yeast as by-product is annually generated from brewing industry and it contains about 50-55% protein with good balance of amino acids. The hydrolysate produced from spent brewer’s yeast may be used in food application. The yield of proteolylic hydrolysis for spent brewer’s yeast and amino acid contents of hydrolysates depend on factors such as temperature, pH value, type of used enzyme and ratio enzyme/substrate, time. Besides, applied hydrolysing methods (batch-, or continuous method) has effected on degree of hydrolysis. With the purpose of how proteolytic hydrolysis having effects on the spent brewer’s yeast for food application in industrial scale, continuous overflow method was used in this study. Bitterness of hydrolysate and the yield of continuous overflow proteolytic hydrolysis process are the two interested factors for protein hydrolysis. In this report, it is dealt with determination for optimal conditions to obtain the highest yield of hydrolysis process and the lowest bitterness of hydrolysate. Response surface methodology (RSM) was used to determine optimal condition for continuous overflow proteolytic hydrolysis of spent brewer’s yeast. The optimal conditions for obtaining high degree of hydrolysis and low bitterness are determined as followings: ratio of enzyme mixture (alcalase 7.5 U/g and flavourzyme 10 U/g), pH at 7.5, hydrolysis temperature at 51oC and hydrolysis time of 9 hours. Under the optimal conditions, the yield of hydrolysis was 59.62% ± 0.027 and the bitterness equivalently with concentration of quinine was 7.86 ± 0.033 μmol /ml.

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Unnikrishnan, Parvathy, Binsi Puthenveetil Kizhakkethil, Jeyakumari Annamalai, Joshy Chalil George, Aliyamveetil Abubacker Zynudheen, George Ninan, and Chandragiri Nagarajarao Ravishankar. "Selective Extraction of Surface-active and Antioxidant Hydrolysates from Yellowfin Tuna Red Meat Protein using Papain by Response Surface Methodology." Indian Journal of Nutrition and Dietetics 56, no. 1 (January 22, 2019): 10. http://dx.doi.org/10.21048//ijnd.2019.56.1.22125.

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The present study was focused on the selective extraction of surface-active and antioxidant hydrolysates from yellowfin tuna (Thunnus albacares) red meat based on separate hydrolytic conditions using papain. The effect of key processing variables viz., enzymesubstrate ratio (0.25-1.5 %) and hydrolysis time (30-240 min) under optimized temperature and pH, on the protein recovery, surface-active and antioxidative properties, was determined using Response Surface Methodology (RSM) with a central composite design. Single and combined effects of the variables on the responses were studied by formulating 13 experimental runs. The coefficient of determination (R2) ranged between 0.73 – 0.99 indicating the suitability of the fitted regression models. The optimum hydrolytic conditions to get hydrolysates having superior surface-active properties were enzyme-substrate ratio (E/S) of 0.41 % and 30 minutes hydrolysis time with a desirability of 0.611. Similarly, the optimum conditions to exhibit the highest antioxidative properties with a desirability of 0.932 were: 1.28 % E/S and 240 minutes hydrolysis time.

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Thu Hien, Pham Thi. "OPTIMIZATION OF CONDITIONS FOR LIMITED PROTEOLYTIC HYDROLYSIS OF SPENT BREWER’S YEAST TO PRODUCE LOW-WEIGHT MOLECULAR PEPTIDE WITH SOME BIOACTIVITIES." Vietnam Journal of Science and Technology 54, no. 4A (March 21, 2018): 259. http://dx.doi.org/10.15625/2525-2518/54/4a/12002.

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Spent brewer’s yeast (Saccharomyces cerevisiae) is a rich source of protein, vitamins and widely used as a raw material for producing bioactive compounds and food ingredients. In the present study, the Box-Behnken design was used to determine the optimal conditions for hydrolysing spent brewer’s yeast using protease (Neutrase) to produce low- weight molecular peptide. The spent brewer’s yeast concentration, concentration of protease, and hydrolysis time are the most important factors used to optimize the protein hydrolysis. For achieving high yields of peptide, the hydrolysis conditions were determined: yeast concentration of 22.72 % (w/w), protease concentration of 4.07 % and hydrolysis time of 16.73 hours. The maximum yield of low-MW peptides was achieved 223.18 mg/g. The obtained bioactive peptide showed capability of antibacterial against Salmonella typhi, Listeria monocytogenes, Staphylococcus aureus and high antioxidant activity at peptide concentration of 100 (µg/ml).

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Teixeira, Amito José, Leonardo Menoncin Weschenfelder, Angela Antunes, Jamile Zeni, Geciane Toniazzo Backes, and Rogério Luis Cansian. "Commercial and non-commercial pectinase and cellulase on the enzymatic hydrolysis efficacy of rice husk and Tifton 85 hay." Acta Scientiarum. Animal Sciences 41, no. 1 (April 8, 2019): 45100. http://dx.doi.org/10.4025/actascianimsci.v41i1.45100.

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The aim of this study was to evaluate the action of commercial and non-commercial cellulase and pectinase on rice husk and Tifton 85 hay hydrolyses. The hydrolysis kinetics of the substrates with commercial cellulase and pectinase were evaluated and the hydrolysis at different temperature and agitation conditions was maximized using experimental design. The combined use of commercial and non-commercial enzymes under optimized conditions was evaluated. The pre-treatment of the residues was also investigated by milling and different concentrations of NaOH. Finally, the effect of the hydrolysis on the bromatological composition of the residues was evaluated. The best hydrolysis times of rice husk and Tifton 85 hay were 10 and 12h for commercial cellulase, 12 and 14h for non-commercial cellulase, 10 and 14h for commercial pectinase and 16 and 20h for non-commercial pectinase, respectively. The highest hydrolysis values were obtained using commercial cellulase with 1:50 (w:v enzyme:water) dilution rate, at 45ºC and 300 rpm agitation for both substrates, reaching 20.6% maximum percentage for Tifton 85 hay and 11.6% for rice husk. The combined use of commercial enzymes did not increase hydrolysis percentage. The pre-treatment using 7.5% NaOH and 0.5 mm grain size significantly increased the rice husk and Tifton 85 hay hydrolyses (60-80%), either using commercial cellulase or pectinase enzymes. The use of non-commercial enzymes provided 18-30% hydrolysis obtained from commercial ones. Bromatological analyzes indicated a reduction in neutral detergent fiber and acid detergent fiber content for rice husk and Tifton 85 hay when using pectinases and commercial cellulases.

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HOSOI, Kazuyuki, Takashi KORENAGA, and Kayoko AMITA. "Hydrolysis of Simazine under Alkaline Conditions." NIPPON KAGAKU KAISHI, no. 9 (1995): 749–52. http://dx.doi.org/10.1246/nikkashi.1995.749.

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Garegg, Per J., Bengt Lindberg, Peter Konradsson, and Ingemar Kvarnström. "Hydrolysis of glycosides under reducing conditions." Carbohydrate Research 176, no. 1 (May 1988): 145–48. http://dx.doi.org/10.1016/0008-6215(88)84066-7.

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Sorokin, Dimitry Y., Sander van Pelt, Tatjana P. Tourova, and Gerard Muyzer. "Microbial Isobutyronitrile Utilization under Haloalkaline Conditions." Applied and Environmental Microbiology 73, no. 17 (July 20, 2007): 5574–79. http://dx.doi.org/10.1128/aem.00342-07.

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ABSTRACT The utilization of isobutyronitrile (iBN) as a C and N source under haloalkaline conditions by microbial communities from soda lake sediments and soda soils was studied. In both cases, a consortium consisting of two different bacterial species capable of the complete degradation and utilization of iBN at pH 10 was selected. The soda lake sediment consortium consisted of a new actinobacterium and a gammaproteobacterium from the genus Marinospirillum. The former was capable of fast hydrolysis of aliphatic nitriles to the corresponding amides and much-slower further hydrolysis of the amides to carboxylic acids. Its partner cannot hydrolyze nitriles but grew rapidly on amides and carboxylic acids, thus acting as a scavenger of products released by the actinobacterium. The soda soil consortium consisted of two Bacillus species (RNA group 1). One of them initiated nitrile hydrolysis, and the other utilized the hydrolysis products isobutyroamide (iBA) and isobutyrate (iB). In contrast to the actinobacterium, the nitrile-hydrolyzing soil Bacillus grew rapidly with hydrolysis products, but it was dependent on vitamins most probably supplied by its product-utilizing partner. All four bacterial strains isolated were moderately salt-tolerant alkaliphiles with a pH range for growth from pH 7.0 to 8.5 up to 10.3 to 10.5. However, both their nitrile hydratase and amidase activities had a near-neutral pH optimum, indicating an intracellular localization of these enzymes. Despite this fact, the study demonstrated a possibility of whole-cell biocatalytic hydrolysis of various nitriles at haloalkaline conditions.

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Shi, Qixun, Matthew P. Mower, Donna G. Blackmond, and Julius Rebek. "Water-soluble cavitands promote hydrolyses of long-chain diesters." Proceedings of the National Academy of Sciences 113, no. 33 (August 1, 2016): 9199–203. http://dx.doi.org/10.1073/pnas.1610006113.

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Water-soluble, deep cavitands serve as chaperones of long-chain diesters for their selective hydrolysis in aqueous solution. The cavitands bind the diesters in rapidly exchanging, folded J-shape conformations that bury the hydrocarbon chain and expose each ester group in turn to the aqueous medium. The acid hydrolyses in the presence of the cavitand result in enhanced yields of monoacid monoester products. Product distributions indicate a two- to fourfold relative decrease in the hydrolysis rate constant of the second ester caused by the confined space in the cavitand. The rate constant for the first acid hydrolysis step is enhanced approximately 10-fold in the presence of the cavitand, compared with control reactions of the molecules in bulk solution. Hydrolysis under basic conditions (saponification) with the cavitand gave >90% yields of the corresponding monoesters. Under basic conditions the cavitand complex of the monoanion precipitates from solution and prevents further reaction.

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Wang, w., Z. Li, J. Z. Liu, Y. J. Wang, S. H. Liu, and M. Sun. " Comparison between thermal hydrolysis and enzymatic proteolysis processes for the preparation of tilapia skin collagen hydrolysates." Czech Journal of Food Sciences 31, No. 1 (January 10, 2013): 1–4. http://dx.doi.org/10.17221/49/2012-cjfs.

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The tilapia (Oreochromis niloticus) skin hydrolysate was produced by thermal or enzymatic hydrolysis processes. Several product characteristics were studied such as the average molecular weight, 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, yield, and protein content, in order to compare thermal hydrolysis and enzymatic proteolysis processes for the hydrolysed tilapia skin collagen production. The effects of the following hydrolysis parameters (retorting time and pH, protease combination, and proteolysis time) were studied. Compared with the thermal hydrolysis process, the enzymatic proteolysis process needed less time and milder conditions, under which hydrolysates could be obtained as low molecular weight antioxidant peptides.

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Wang, Min, Li Qin Xu, Ci Li, Bing Ying Jiang, and Jia Qing Xie. "Intramolecular Nucleophilic Substitution in the Hydrolysis of Bis(4-Nitrophenyl) Phosphate Ester Catalyzed by the Metallomicelle." Advanced Materials Research 554-556 (July 2012): 345–48. http://dx.doi.org/10.4028/www.scientific.net/amr.554-556.345.

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A macro-cyclic Schiff base ligand and the corresponding Cu (II) and Ni (II) complexes were synthesized and characterized. And the catalytic efficiency of the metallomicelles made of these complexes and noninonic micelle Brij35, as mimetic hydrolytic metalloenzyme, was investigated in the catalytic hydrolysis of bis(p-nitrophenyl) phosphate (BNPP) in this paper. The results show that the rate of the BNPP hydrolysis in the metallomicelles is about 106 -fold faster than that of the BNPP spontaneous hydrolysis in aqueous solution at the same conditions. The analysis of the characteristic absorption spectra of the hydrolytic reaction systems indicates that the key intermediate, composing of BNPP and Ni(II) or Cu(II) complexes, has been formed and the catalytic hydrolysis of BNPP is an intramolecular nucleophilic substitution reaction. Based on the results of characteristic absorption spectra, the mechanism of BNPP catalytic hydrolysis has been proposed and also the corresponding kinetic mathematical model has been established.

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Levitt, David B., Gary A. Pope, and Stephane Jouenne. "Chemical Degradation of Polyacrylamide Polymers Under Alkaline Conditions." SPE Reservoir Evaluation & Engineering 14, no. 03 (May 16, 2011): 281–86. http://dx.doi.org/10.2118/129879-pa.

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Summary Hydrolysis of polyacrylamide (PAM) -based polymers is rapid and extensive under the alkaline conditions typical of alkaline/ surfactant-polymer (ASP) flooding. Even at room temperature, significant hydrolysis occurs within 1 to 2 months in the presence of sodium carbonate. While this implies that polymers used in ASP floods will rapidly become susceptible to precipitation with divalent cations, in most cases the alkali present will be the most sensitive component to precipitation, so this may be a moot point. Also, autoretarding kinetics under alkaline conditions limit hydrolysis at 100°C, whereas complete hydrolysis occurs under neutral conditions. Furthermore, in-situ hydrolysis of initially unhydrolyzed PAM is proposed as a promising strategy for ASP floods because the injectivity of the unhyrolyzed PAM will be greater than that of hydrolyzed PAM (HPAM) because of its lower initial viscosity. The lower initial viscosity is not a disadvantage because once it has been hydrolyzed in-situ, its viscosity will increase.

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Kuan, Dingyaw, Lingmei Dai, Dehua Liu, Hongjuan Liu, and Wei Du. "Efficient Biodiesel Conversion from Microalgae Oil of Schizochytrium sp." Catalysts 9, no. 4 (April 6, 2019): 341. http://dx.doi.org/10.3390/catal9040341.

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Abstract: Microalgae oil has been regarded as a promising feedstock for biodiesel production. However, microalgae oil usually contains some non-lipid components, such as pigments. Microalgae oil could be converted to biodiesel effectively with a two-step process to decrease the negative effect caused by by-product glycerol generated in traditional biodiesel production process. Firstly, microalgae oil was hydrolysed to free fatty acids (FFAs) and then FFAs were converted to methyl ester. In this study, the hydrolysis of microalgae oil from Schizochytrium sp. was systematically investigated and microalgae oil could be hydrolysed effectively to FFAs at both non-catalytic and acid-catalytic conditions. The hydrolysis degree of 97.5% was obtained under non-catalytic conditions of 220 °C and a water to oil ratio of 10:1 (w:w). The hydrolysis degree of 97.1% was obtained with the optimized sulphuric acid catalytic conditions of 95 °C, and a ratio of water to oil 3:1. The lipase Novozym435-mediated esterification with the hydrolysed FFAs was explored and a FAME (Fatty Acids Methyl Ester) yield of 95.1% was achieved. The conversion of different FFAs also was compared and the results indicated that lipase Novozym435-mediated methanolysis was effective for the preparation of biodiesel as well as poly unsaturated fatty acids (PUFAs).

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Lin, Kuan-Hsuan, Toshiharu Enomae, and Feng-Cheng Chang. "Cellulose Nanocrystal Isolation from Hardwood Pulp using Various Hydrolysis Conditions." Molecules 24, no. 20 (October 16, 2019): 3724. http://dx.doi.org/10.3390/molecules24203724.

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To expand the application field of the pulping industry, this study conducted a series of sample preparations for processing cellulose nanocrystals (CNCs) from a dry hardwood pulp to achieve optimal sulfuric acid hydrolysis. The properties of laboratory-prepared pulp CNCs (P-CNCs) were investigated with different preparation conditions including sulfuric acid concentrations, hydrolysis temperatures, and hydrolysis durations. Results showed a gradient of color changes observed with the increase of hydrolysis duration and temperature. Under certain conditions, the derived P-CNCs exhibited nanoscale dimensions, detected by transmission electron microscopy, and a crystallinity index similar to commercial products. In addition, the surface sulfate groups were assumed to be contributed by sulfuric acid hydrolysis. However, a high acid concentration and long hydrolysis processing duration introduced more sulfate groups on the derived P-CNCs, which may have acted as flame retardants and, thus, increased the amount of char residue.

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Zainol, M. K., F. W. Abdul Sukor, A. Fisal, T. C. Tuan Zainazor, M. R. Abdul Wahab, and A. I. Zamri. "Optimization of enzymatic protein hydrolysis conditions of Asiatic hard clam (Meretrix meretrix)." Food Research 5, no. 4 (July 25, 2021): 153–62. http://dx.doi.org/10.26656/fr.2017.5(4).701.

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This study was aimed to optimise the Alcalase® enzymatic hydrolysis extraction of Asiatic hard clam (AHC) (Meretrix meretrix) protein hydrolysate in terms of hydrolysis time, hydrolysis temperature, hydrolysis pH, and concentration of enzyme. Protein hydrolysate produced from AHC (M. meretrix) meat was used to determine the optimum hydrolysis conditions. Hydrolysis of AHC meat was optimised using the Central Composite Design Response Surface Methodology (RSM) (CCD). The relationship between four parameters such as temperature (45 – 65°C), enzyme to substrate concentration (1 – 2%), hydrolysis time (60 – 180 mins), and pH (7.5 – 9.5) to the degree of hydrolysis was investigated. The optimum conditions for enzymatic hydrolysis of AHC meat to achieve the maximum degree of hydrolysis (DH) were observed at 65°C, enzyme to substrate concentration of 1%, hydrolysis time of 60 mins, and pH 7.5. The enzymatic protein hydrolysis of AHC meat was predicted using a two factors interaction (2FI) model. Under these optimum conditions, DH's predicted value was 97.41%, which was close to the experimental value (97.89%). The freeze-dried protein hydrolysate powder was characterized concerning the proximate composition. Proximate analysis revealed that the AHC meat contains 7.92±1.76% of moisture, 2.23±0.89% of crude fat, 1.98±0.82 of ash, and 10.53±0.04% of crude protein. While the Asiatic hard clam protein hydrolysate (AHCPH) composed 9.12±0.02% of moisture, 0.80±0.29% of crude fat, and 27.76±0.10% of ash. The protein hydrolysate produced also contained high protein content (50.09±0.88%) and may serve as a good protein source.

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Kaur, S., T. Huppertz, and T. Vasiljevic. "Milk protein hydrolysis by actinidin: Influence of protein source and hydrolysis conditions." International Dairy Journal 118 (July 2021): 105029. http://dx.doi.org/10.1016/j.idairyj.2021.105029.

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Botic, Tatjana, and Nadezda Iliskovic. "Hydrolysis of tanned leather wastes under alkaline, acidic and oxidative conditions." Chemical Industry 60, no. 1-2 (2006): 23–26. http://dx.doi.org/10.2298/hemind0602023b.

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Different wastes in large quantities are the outcome or the by-product of processes in the tanning industry. The largest part of solid wastes is collagen based and obtained in the reprocessing steps of tanned and non-tanned products. The quality collagen substance obtained from wastes of the leather industry used as a supporting material in many reprocessing industries. Hydrolysis is the basic step of collagen processing, namely the shortening of its polypeptide chain. The main goal of this investigation was to examine the influence of the following parameters on the extent of collagen hydrolysis: type and quantity of reagent used for hydrolysis temperature of hydrolysis, pH, duration of hydrolysis as well as the dimensions of the "shavings" samples. The change of molar mass during hydrolysis was monitored by UV-spectroscopy. Special attention was paid to the dechroming process of the collagen hydrolysate.

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29

Sroka, Zbigniew, Wojciech Cisowski, Magdalena Seredyńska, and Maria Łuczkiewicz. "Phenolic Extracts from Meadowsweet and Hawthorn Flowers Have Antioxidative Properties." Zeitschrift für Naturforschung C 56, no. 9-10 (October 1, 2001): 739–44. http://dx.doi.org/10.1515/znc-2001-9-1012.

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AbstractFrom the flowers of meadowsweet and inflorescence of hawthorn the whole set of phenolic acids and flavonoids was analysed by TLC . Phenolic compounds were determined both as free ones and those liberated by hydrolysis. Moreover, ethyl ether and ethyl acetate extracts obtained from the analysed plants before and after alkaline and enzymatic hydrolyses were evaporated under reduced pressure and residues were analysed for their antioxidative properties. The weakest antioxidative activity was observed with the remaining residue after evaporation of ethyl ether extract obtained from enzymatically (β-glucosidase) hydrolysed hawthorn inflorescence water extract. The strongest antioxidative activity was noticed with the remaining residues after evaporation of ethyl ether extracts obtained from non-hydrolysed and hydrolysed in alkaline conditions of meadowsweet flower water extracts.The residues from meadowsweet flowers exhibited stronger antioxidative properties than residues obtained from hawthorn inflorescence and can be recommended as margarine preservatives.

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Didelot, Sandrine, Stephanie Bordenave-Juchereau, Eric Rosenfeld, Jean-Marie Piot, and Frederic Sannier. "Peptides released from acid goat whey by a yeast-lactobacillus association isolated from cheese microflora." Journal of Dairy Research 73, no. 2 (February 14, 2006): 163–70. http://dx.doi.org/10.1017/s0022029905001512.

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Seven lactobacilli and a variety of microflora extracted from twenty five commercial cheeses were grown on unsupplemented acid goat whey and screened for their capacity to hydrolyse whey proteins [α-lactalbumin (α-la) and β-lactoglobulin (β-lg)] and to generate peptides. Fermentations were performed aerobically or anaerobically at 37 °C using crude or pre-heated whey (10 min at 65, 75 or 85 °C). Under aerobic conditions, growth of lactobacilli was poor and protein hydrolysis did not occur. Anaerobic conditions slightly increased lactobacilli growth but neither β-lg hydrolysis nor peptide generation were observed. More than 50% of α-la was digested into a truncated form of α-la (±12 kDa) in crude whey and whey pre-heated at 65 °C. Twenty-five microflora extracted from raw milk cheeses were screened for their proteolytic activities on acid goat whey under the conditions previously described. Eight of them were able to hydrolyse up to 50% of α-la mainly during aerobic growth on crude or pre-heated whey. The corresponding hydrolysates were enriched in peptides. The hydrolysate involving microflora extracted from Comté cheese after or at 18 months ripening was the only one to exhibit hydrolysis of both α-la and β-lg. Microbiological analysis showed that microorganisms originating from Comté cheese and capable of growth on unsupplemented whey consisted of Candida parapsilosis and Lactobacillus paracasei. Fermentation kinetic profiles suggested that peptides were released from α-la hydrolysis. The co-culture of both microorganisms was required for α-la hydrolysis that occurred concomitantly with the pH decrease. During whey fermentation, Cand. parapsilosis excrete at least one protease responsible for α-la hydrolysis, and Lb. paracasei is responsible for medium acidification that is required for protease activation.

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Ma, Yong Sheng, Lin Tong Wang, Xian Hui Sun, Bing Chen Ma, Jian Wen Zhang, Fan Qiang Gao, and Cheng Liang Liu. "Study on Hydrolysis Conditions of Flavourzyme in Soybean Polypeptide Alcalase Hydrolysate." Advanced Materials Research 652-654 (January 2013): 435–38. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.435.

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Soybean protein Alcalase hydrolysate was further hydrolyzed by adopting Flavourzyme. From this further hydrolysis reaction, bitter of soybean polypeptide mixture was reduced distinctly. The optimal hydrolysis conditions of Flavourzyme was determined as that pH was 7.0 at temperature 50°C and E/S(ratio of enzyme and substrate) was 20LAPU/g. Bitter taste value was reduced to 2 after Flavourzyme hydrolysis reaction for 2 hours in optimal hydrolysis conditions. The change of molecular weight distribution range from Alcalase hydrolysate to Flavourzyme hydrolysate was not obvious. DH (Degree of hydrolysis) of soybean protein hydrolysate was increased to 24.2% which was improved 3.5% than Alcalase hydrolysate. Protein recovery proportion was increased to 73.2% which was improved 0.8% than Alcalase hydrolysate.

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32

Jin, Mengting, Mingxiu Liu, Petr Nachtigall, Lukáš Grajciar, and Christopher James Heard. "Mechanism of Zeolite Hydrolysis under Basic Conditions." Chemistry of Materials 33, no. 23 (December 1, 2021): 9202–12. http://dx.doi.org/10.1021/acs.chemmater.1c02799.

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33

Gómez-Bombarelli, Rafael, Emilio Calle, and Julio Casado. "Mechanisms of Lactone Hydrolysis in Acidic Conditions." Journal of Organic Chemistry 78, no. 14 (June 17, 2013): 6880–89. http://dx.doi.org/10.1021/jo4002596.

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Oberhauser, Werner, and Gabriele Manca. "Catalytic Phosphite Hydrolysis under Neutral Reaction Conditions." Inorganic Chemistry 57, no. 9 (April 12, 2018): 4824–27. http://dx.doi.org/10.1021/acs.inorgchem.8b00546.

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35

Di Meo, Florent, Michele Steel, Picard Nicolas, Pierre Marquet, Jean-Luc Duroux, and Patrick Trouillas. "Acylglucuronide in alkaline conditions: migration vs. hydrolysis." Journal of Molecular Modeling 19, no. 6 (February 19, 2013): 2423–32. http://dx.doi.org/10.1007/s00894-013-1790-3.

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36

Faisal, M., H. Daimon, and K. Fujie. "Hydrolysis of glycylglycine in subcritical water conditions." Journal of Physics: Conference Series 121, no. 8 (July 1, 2008): 082002. http://dx.doi.org/10.1088/1742-6596/121/8/082002.

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37

Liu, Zhi De, Xin Zhang, Mi Mi Wang, and Dong Zhang. "Study on the Hydrolysis of PET Catalyzed by Carbonates under Microwave Irradiation." Advanced Materials Research 1078 (December 2014): 36–39. http://dx.doi.org/10.4028/www.scientific.net/amr.1078.36.

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A study for optimizing the experimental conditions for the hydrolysis of polyethylene terephthalate (PET) catalyzed by carbonates was performed. The main influence factors of PET microwave hydrolytic reaction, such as the reaction temperature, time and catalyst dosage, were confirmed and these effects on the catalysis of PET microwave hydrolysis were studied in detail. The results showed that the sequence of influence factors was reaction temperature>reaction time> catalyst dosage. The optimal experimental conditions under the catalyst of basic zinc carbonate were that the catalyst dosage, 0.75%; the reaction time, 210 min; the reaction temperature, 200°C.

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38

Joseph, S. K., T. Esch, and W. D. Bonner. "Hydrolysis of inositol phosphates by plant cell extracts." Biochemical Journal 264, no. 3 (December 15, 1989): 851–56. http://dx.doi.org/10.1042/bj2640851.

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A gel-filtered soluble fraction prepared from suspension-cultured Nicotiana tabacum cells hydrolysed inositol mono-, bis- and tris-phosphates. At a concentration of 7.5 microM the rates of hydrolysis followed the sequence Ins(1,4,5)P3 greater than Ins(1,4)P2 greater than Ins(4)P congruent to Ins(1)P. The major products of Ins(1,4,5)P3 hydrolysis identified by h.p.l.c. were Ins(1,4)P2 and Ins(4,5)P2. Ins(1,4)P2 was hydrolysed exclusively to Ins(4)P. The inclusion of Ca2+ in the incubation buffer markedly stimulated the hydrolysis of all the inositol phosphate substrates. Under identical conditions, Ca2+ inhibited the hydrolysis of inositol phosphates by soluble extracts prepared from rat brain. Half-maximal stimulation of Ins(1,4)P2 hydrolysis was obtained at free [Ca2+] of 0.6 and 1.2 microM when the Mg2+ concentration in the incubations was 0.3 and 1.0 mM respectively. This effect of Ca2+ was exerted solely by increasing the Vmax. of hydrolysis without affecting the Km for Ins(1,4)P2. Again, in contrast with brain, the hydrolysis of inositol bis- or mono-phosphates was insensitive to high concentrations of Li+. We conclude that plants contain specific Li+-insensitive inositol phosphate phosphatases that are regulated by low concentrations of Ca2+ in a manner which is different from that observed in mammalian tissues.

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H�kansson, Helena, and Per Ahlgren. "Acid hydrolysis of some industrial pulps: effect of hydrolysis conditions and raw material." Cellulose 12, no. 2 (April 2005): 177–83. http://dx.doi.org/10.1007/s10570-004-1038-6.

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Syrchin, S. O. "OPTIMIZATION OF HYDROLYSIS CONDITIONS OF WHEAT STRAW BY ENZYME PREPARATION FROM Fennellia sp. 2806." Biotechnologia Acta 10, no. 6 (December 2017): 61–68. http://dx.doi.org/10.15407/biotech10.06.061.

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Baghel, Madhuri, Sangeeta Patil, Mukesh Sharma, Hemant R. Badwaik, Ruchi Khare Shrivastava, Kushagra Nagori, and Sadhana Rajput. "Degradation Kinetic Study and Mechanistic Interpretation of Hydrolysis of Pidotimod by LC-MS/MS: A QbD Assisted Stability Indicating Method Development." Asian Journal of Chemistry 34, no. 11 (2022): 2797–805. http://dx.doi.org/10.14233/ajchem.2022.23796.

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The stability of pidotimod was investigated in this study under ICH-recommended stress degradation conditions. To explore the degradation kinetics of pidotimod, a QbD assisted stability indicating assay method was designed and validated according to ICH Q2 (R1) guidelines. The impacts of hydrogen and hydroxide ions were explored, with a focus on the kinetics of pidotimod hydrolytic degradation to identify the rate laws, which were parameterized using linear regression analysis. The degradation product (DP2) was formed as a major degradation product of hydrolysis. Four known and one unknown degradation product were formed under hydrolysis. Degradation of pidotimod in acid and base degradation follows first-order reaction kinetics while the neutral degradation follows zero-order reaction kinetics. The observed degradation products of pidotimod under hydrolytic degradation were identified by LC-MS/MS analysis and a mechanism of hydrolysis is proposed.

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Firsty, Virginia Ghita, Ji Yeon Jeong, Yang Mo Gu, Jin Hyung Lee, and Soo-Jeong Shin. "High Cellulose Purity by Acid Hydrolysis Pretreatment on Kenaf Outer Bast." Applied Sciences 13, no. 1 (December 27, 2022): 334. http://dx.doi.org/10.3390/app13010334.

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Acid hydrolysis treatment of kenaf outer bast fiber can produce pure cellulose content and hydrolyzed hemicellulose to monosaccharides. The effects of various reaction temperatures (110–130 °C), acid concentrations of sulfuric acid (0.25–1.00 N), and reaction times (60–120 min) were investigated as the optimum condition to gain pure cellulose content. A 1H NMR spectroscopy was used to analyze the carbohydrate content in the reaction of acid hydrolysis treatment. The results showed that optimum conditions for acid hydrolysis refer to two treatment prospects. First, a higher reaction temperature of 130 °C was necessary to increase the reaction for the hydrolyzes of hemicellulose—the high yield content produced by 0.25 N sulfuric acid with a short reaction time of 60 min. to improve the purity of cellulose, provided by the high sulfuric acid solution of 1.00 N for 120 min. Hemicellulose was hydrolyzed at almost 100% based on the two optimal conditions. The analysis revealed that a high temperature of acid hydrolysis was the primary treatment to hydrolyze hemicellulose to increase high pure cellulose from the kenaf outer bast fiber.

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Lisak, Katarina, Jose Toro-Sierra, Ulrich Kulozik, Rajka Božanić, and Seronei Chelulei Cheison. "Chymotrypsin selectively digests β-lactoglobulin in whey protein isolate away from enzyme optimal conditions: Potential for native α-lactalbumin purification." Journal of Dairy Research 80, no. 1 (September 21, 2012): 14–20. http://dx.doi.org/10.1017/s0022029912000416.

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The present study examines the resistance of the α-lactalbumin to α-chymotrypsin (EC 3.4.21.1) digestion under various experimental conditions. Whey protein isolate (WPI) was hydrolysed using randomised hydrolysis conditions (5 and 10% of WPI; pH 7·0, 7·8 and 8·5; temperature 25, 37 and 50 °C; enzyme-to-substrate ratio, E/S, of 0·1%, 0·5 and 1%). Reversed-phase high performance liquid chromatography (RP-HPLC) was used to analyse residual proteins. Heat, pH adjustment and two inhibitors (Bowman–Birk inhibitor and trypsin inhibitor from chicken egg white) were used to stop the enzyme reaction. While operating outside of the enzyme optimum it was observed that at pH 8·5 selective hydrolysis of β-lactoglobulin was improved because of a dimer-to-monomer transition while α-la remained relatively resistant. The best conditions for the recovery of native and pure α-la were at 25 °C, pH 8·5, 1% E/S ratio, 5% WPI (w/v) while the enzyme was inhibited using Bowman–Birk inhibitor with around 81% of original α-la in WPI was recovered with no more β-lg. Operating conditions for hydrolysis away from the chymotrypsin optimum conditions offers a great potential for selective WPI hydrolysis, and removal, of β-lg with production of whey protein concentrates containing low or no β-lg and pure native α-la. This method also offers the possibility for production of β-lg-depleted milk products for sensitive populations.

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Guo, Liang, Ming Min Lu, and Yan Zong. "The Optimal Conditions on Excess Sludge Hydrolysis and Reduction Using Multi-Enzyme." Advanced Materials Research 955-959 (June 2014): 2889–92. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.2889.

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A large quantity of excess sludge is produced during the sewage treatment process, which will cause serious environmental problem without being treated properly. In this paper, a new multi-enzyme was added in the excess sludge to enhance the sludge hydrolysis and reduction, and the treatment conditions of hydrolysis time, dosage, hydrolysis temperature with multi-enzymes was optimized in this study. The multi-enzymes could promote the solubilization of suspended sludge solids and the degradation of macromolecular organic matter. The effect of excess sludge digestion was enhanced significantly at the condition of 30 °C, 1.5 mL multi-enzyme after 5 h hydrolysis for per 100 mL excess sludge. And the optimal hydrolysis conditions were determined by detecting the concentration of carbohydrate, soluble protein, SCOD and sludge’s lysis rates, and the effect of sludge reduction was investigatied by the VSS solubility.

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HOMSUWAN, NALINEE, SUWATTANA PRUKSASRI, and BUDSARAPORN NGAMPANYA. "PROTEIN QUALITY IMPROVEMENT AND ANTI-NUTRITIONAL FACTORS REDUCTION IN SOYBEAN MEAL BY Bacillus velezensis K1." JOURNAL OF SUSTAINABILITY SCIENCE AND MANAGEMENT 17, no. 7 (July 31, 2022): 88–103. http://dx.doi.org/10.46754/jssm.2022.07.007.

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The solid-state fermentation (SSF) of soybean meal (SBM) by Bacillus velezensis K1 to improve protein quality and reduce allergenic proteins as well as raffinose family oligosaccharides was investigated in this research paper. The fermentation parameters affected protein hydrolysis, namely soybean meal moisture, size of inoculums, time and temperature of fermentation were evaluated in the soybean meal. The best solid-state fermentation conditions with the highest degree of hydrolysis (16.65 ± 4.08%) were 50% (w/w) moisture content, 10% (v/w) inoculum size, 40°C and 72 hours fermentation. Under these optimal conditions, large proteins in the soybean meal were hydrolysed. Proteins with molecular weight <10 kDa increased significantly from 34.05 to 48.22% (P<0.05). Additionally, allergens (glycinin and β-conglycinin) and raffinose family oligosaccharides decreased. The bands representing glycinin and β-conglycinin on SDS-PAGE were considerably reduced and their degradations were 96.47% and 49.60%, respectively. The raffinose family oligosaccharides, primarily stachyose and raffinose also decreased by 73.57% and 22.76%, respectively. With the capability of producing protease and other carbohydrate hydrolytic enzymes (cellulase, pectinase, amylase and invertase), B. velezensis K1 presents great potential for increasing the nutritional quality of the soybean meal as an ingredient in the feed industry.

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Tsai, Hung Jung, Pay Yau Huang, Chung Ming Tan, and Tang Feng Chang. "The Experimental Study on Mechanical Polishing on Materials with Hydrolysis Reaction." Key Engineering Materials 739 (June 2017): 182–86. http://dx.doi.org/10.4028/www.scientific.net/kem.739.182.

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The hydrolytic properties of LiAlO2 (LAO) are important factors for its applications on LED fabrication. During soft pad polishing process, the H2O in the slurry is deleterious for LAO surface polishing results. The current study develops a material removal rate model for materials with hydrolysis reaction to predict the result of polishing process.The current research conducts the experimental studies to investigate the material removal rate and its mechanism during the soft pad polishing process. In the experimental study, the hydrolytic properties of LAO have been tested to understand the hydrolysis speed with different operation parameters to assist the development of the theoretical model. Also the material removal rates of LAO with hydrolytic property have been measured under different soft pad polishing operating conditions. The experimental results provide the hydrolytic properties of LiAlO2 to understanding of the mechanism on polishing process.

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47

Hudečková, Helena, Petra Šupinová, and Libor Babák. "Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 65, no. 1 (2017): 35–40. http://dx.doi.org/10.11118/actaun201765010035.

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Finding of optimal hydrolysis conditions is important for increasing the yield of saccharides. The higher yield of saccharides is usable for increase of the following fermentation effectivity. In this study optimal conditions (pH and temperature) for amylolytic enzymes were searched. As raw material was used waste bread. Two analytical methods for analysis were used. Efficiency and process of hydrolysis was analysed spectrophotometrically by Somogyi-Nelson method. Final yields of glucose were analysed by HPLC. As raw material was used waste bread from local cafe. Waste bread was pretreated by grinding into small particles. Hydrolysis was performed in 100 mL of 15 % (w/v) waste bread particles in the form of water suspension. Waste bread was hydrolysed by two commercial enzymes. For the liquefaction was used α‑amylase (BAN 240 L). The saccharification was performed by glucoamylase (AMG 300 L). Optimal conditions for α‑amylase (pH 6; 80 °C) were found. The yield of total sugars was 67.08 g∙L-1 (calculated to maltose). As optimal conditions for glucoamylase (pH 4.2; 60 °C) were found. Amount of glucose was 70.28 g∙L1. The time of waste bread liquefaction was 180 minutes. The time of saccharification was 90 minutes. The results were presented at the conference CECE Junior 2014.

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Tran, Hien Xuan, Huong Lien Huynh, and Thanh Trung Nguyen. "Effect of Hydrolysis on Tannin and Carotenoid Contents, and Antioxidant Activity of Pouteria campechiana." International Journal of Agricultural Sciences 4, no. 1 (March 8, 2021): 1. http://dx.doi.org/10.25077/ijasc.4.1.1-7.2020.

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The medicinal properties of Pouteria campechiana fruit in Vietnam currently have not been studied much. This study was conducted to evaluate hydrolysis's effect on the carotenoid, tannin, and antioxidant activity through the correlation between IC50 and TPC values of Pouteria campechiana extract. This study examined hydrolysis conditions, such as enzyme type, enzyme concentration, temperature, and hydrolysis time. Experimental results showed that at pectinase enzyme concentration of 0.6 wt%, cellulase enzyme concentration of 0.6 wt%, at hydrolysis temperature of 600C, and 65 minutes for hydrolysis, the study found carotenoid of 115.14±4.14 (µg/g) and tannin of 45.88±2.37 (mgTAE/g)in the extract. IC50 value (7.82±0.21 mg/mL) and TPC content were highly correlated (R2=0.98). This study's results contributed to the provision of valuable scientific data on Pouteria campechiana fruit, especially for the food industry

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Mateo, Soledad, Pilar Mateo, Marco Barbanera, Cinzia Buratti, and Alberto J. Moya. "Acid Hydrolysis of Olive Tree Leaves: Preliminary Study towards Biochemical Conversion." Processes 8, no. 8 (July 23, 2020): 886. http://dx.doi.org/10.3390/pr8080886.

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Olive tree leaves, an abundant agricultural by-product without enough industrial market outlets, are presented in this study as a relevant resource of available carbohydrates to be chemically treated for monomeric sugar production. Characterization of two main granulometric fractions is the starting point for testing the specific effect and the relevance of three main factors (time, temperature, and sulfuric acid concentration) on diluted acid hydrolysis with respect to oligosaccharides, simple sugars, and fermentation inhibitory compounds production. The selected conditions (100 ∘ C, 90 min, and 6% w/w H 2 SO 4 ) to perform the small scale hydrolytic process, considering response surface methodology (2 3 factorial design with center points), implied production of acetic acid and hydroxymethylfurfural in concentrations not exceeding 1.10 kg m − 3 and 0.25 kg m − 3 , respectively. Thus, these experimental conditions were the reference framework to evaluate the effect of a meaningful scaling stage in a hydrolysis reactor, considering kinetic parameters based on hydrolysis rates and d-glucose and d-xylose generation.

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Liu, Chia-Min, Kuan-Hsuan Lin, Tzu-Cheng Chang, and Feng-Cheng Chang. "Preparation and characterization of moso bamboo-based cellulose nanowhiskers under various acid hydrolysis conditions." BioResources 14, no. 1 (December 12, 2018): 1077–90. http://dx.doi.org/10.15376/biores.14.1.1077-1090.

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The influence of acid hydrolysis conditions on cellulose nanowhiskers (CNW) made from moso bamboo (Phyllostachys edulis) was investigated in this study. Procedures with or without an alcohol–toluene extraction were tested using different acid concentrations and hydrolysis durations. The alcohol–toluene extract had no significant effect on the properties of bamboo cellulose nanowhiskers (BCNW). According to the results, a sulfuric acid concentration of 46% with 2 h of hydrolysis and a concentration of 55% with 1 h of hydrolysis were ideal for preparing BCNW because the product had a relatively high crystallinity index. In addition, the surface functional groups of the products obtained from different sulfuric acid hydrolysis conditions were similar. However, groups treated with lower acid concentrations exhibited slightly stronger thermal stability than those treated with higher acid concentrations.

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Journal articles on the topic 'Hydrolysis conditions'

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