Academic literature on the topic 'Amphora sp'
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Journal articles on the topic "Amphora sp"
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Sujarwani, Siyam, Saifuddin Saifuddin, and I. Gede Sridana Wisnawa. "TEKNIK PRODUKSI MASSAL Amphora sp. SEBAGAI BAHAN KONSENTRAT UNTUK PAKAN LARVA ABALON (Haliotis squamata)." Buletin Teknik Litkayasa Akuakultur 14, no. 1 (November 14, 2016): 33. http://dx.doi.org/10.15578/blta.14.1.2016.33-37.
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Amphora sp. merupakan kelompok bentik diatom bersel tunggal, hidup pada substrat kasar, dapat membentuk koloni, berkelompok membentuk flok, dan sangat banyak ditemukan pada pemeliharaan larva ikan udang dan kekerangan. Kegiatan ini bertujuan untuk memperoleh konsentrat Amphora sp. sebagai pakan larva abalon. Produksi konsentrat dilakukan melalui kultur Amphora sp. skala kecil hingga massal. Konsentrat yang diperoleh melalui pemanenan menggunakan bak volume 100 L disaring menggunakan saringan ukuran 30 µm dan keranjang yang dibuat dengan mengendapkan sel Amphora sp. Konsentrat yang diperoleh disimpan dalam laboratorium dan lemari es. Hasil yang diperoleh menunjukkan bahwa kultur Amphora sp. dengan menggunakan bak ukuran 1 m3 diperoleh kepadatan sel sebesar 75 x 104 - 200 x 104 sel/cm2 dan jumlah konsentrat Amphora sp. sebesar 272,8-882,87 g. Pengembangan pakan alami sebagai bahan konsentrat diharapkan dapat menjamin ketersediaan pakan alami pada proses pembenihan sehingga dapat meningkatkan pertumbuhan dan sintasan benih abalon
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Khumaidi, Ach, and Astik Umiyah. "Potential Antivirus Viral Nervous Necrosis Methanol extract of Amphora sp. in Cantang Grouper (Epinephelus sp.)." Samakia : Jurnal Ilmu Perikanan 10, no. 2 (October 23, 2019): 114–20. http://dx.doi.org/10.35316/jsapi.v10i2.538.
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Cantang grouper received more serious attention from grouper fish farmers due to high export interest, but the attack of viral nervous necrosis (VNN) became a major obstacle in its cultivation. This study aims to explore the antiviral potential of diatom Amphora sp. to counter the VNN attack on Cantang groupers. The method used is the extraction of Amphora sp. with absolute methanol solvent. The extraction results were tested in vivo by giving Amphora sp. with different concentrations, namely: 17 µg / ml, 33 μg / ml, 50 μg / ml, and administration of extracts by challenging the 17 μg / ml + VNN, 33 μg / ml + VNN, 50 μg / ml + VNN. Fish treated with Amphora sp. also challenged by giving VNN Positive fish meat. During the period of rearing fish observed clinical behavior and symptoms. After the fish were raised for 15 days, the fish harvested were analyzed using histology, RT-PCR, and CPI methods (using the immuno ratio software) to see the HSP immune response obtained from the administration of Amphora sp. to find out its potential as a natural antivirus. From several test parameters, the concentration of extract 50 mg / ml + VNN was given to give the best response in the CPI analysis with a DAB value (61.3%). These results indicate that the methanol extract of Amphora sp. has the potential to be used as an antiviral candidate in Cantang grouper fish.
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Khumaidi, Ach, Astik Umiyah, Abdul Muqsith, and Abdul Wafi. "POTENSI ANTIOKSIDAN EKSTRAK METANOL DIATOM Amphora sp." Jurnal Akuakultur Rawa Indonesia 9, no. 1 (June 24, 2021): 13–21. http://dx.doi.org/10.36706/jari.v9i1.13687.
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Diatoms are a type of microalgae with a quite strong potential in the health sector as antioxidants, anticancer, and antivirals. But until now in Indonesia is still very rarely carried out research on the antioxidant potential of diatoms. The purpose of this study was to determine the antioxidant potential of Amphora sp. extracted with methanol. The method used in the extraction process is maceration, with a ratio of sample and methanol 1: 3 (300 g: 900 ml). The evaporation process compacted maserate resulting from maceration, then analyzed the total chlorophyll content, total flavonoids, and total phenols. Amphora sp. extraction results showed good potential with 7.08 ppm chlorophyll content, total flavonoids 6,299 ppm, and total phenol 7,085 ppm, and IC50 DPPH values of 3332.5 ppm. The IC50 value of the extract of Amphora sp. still classified as very weak antioxidant activity, but in general the extract of Amphora sp. has other bioactive potentials such as chlorophyll, flavonoids, and total phenol which can be used as material for further studies for the development of natural medicinal ingredients from Amphora sp.Key words: antioxidant, diatome, DPPH, macaration, methanol.
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Cavalcante, KP, PI Tremarin, and TAV Ludwig. "New records of amphoroid diatoms (Bacillariophyceae) from Cachoeira River, Northeast Brazil." Brazilian Journal of Biology 74, no. 1 (February 2014): 257–63. http://dx.doi.org/10.1590/1519-6984.24512.
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Amphoroid taxa have been revised in recent decades. Many species formerly assigned to Amphora have been transferred to other recently proposed genera, as Seminavis (Naviculaceae) and Halamphora (Catenulaceae). In Brazil, there are few studies focused on amphoroid taxonomy. This study presents a taxonomic investigation of five uncommon amphoroid taxa from Brazilian diatom flora: Seminavis pusilla, S. strigosa, Amphora ectorii, Halamphora ghanensis and Halamphora sp. Seminavis strigosa is identical in valve morphology and morphometrical data to Amphora twenteana, and its synonymy is proposed. Seminavis pusilla, poorly found in Brazilian waters, has expanded its distribution. Halamphora ghanensis is a new record to American continent while Amphora ectorii are new to Brazilian aquatic systems. Halamphora sp. has distinct ultrastructural features in relation to similar species and is probably new for science.
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Boukhris, Saoussan, Khaled Athmouni, Ibtissem Hamza-Mnif, Rayda Siala-Elleuch, Habib Ayadi, Moncef Nasri, and Alya Sellami-Kamoun. "The Potential of a Brown Microalga Cultivated in High Salt Medium for the Production of High-Value Compounds." BioMed Research International 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/4018562.
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Amphora sp. was isolated from the Sfax Solar Saltern and cultivated under hypersaline conditions. It contains moderate rates of proteins, lipids, sugars, and minerals and a prominent content of bioactive compounds: polyphenols, chlorophyll a, carotenoids, and fatty acids. The analysis of fatty acids with GC/MS showed that the C16 series accounted for about 75% of Amphora sp. lipids. Saturated fatty acids whose palmitic acid was the most important (27.41%) represented 41.31%. Amphora sp. was found to be rich in monounsaturated fatty acids with dominance of palmitoleic acid. It also contains a significant percentage of polyunsaturated fatty acids with a high amount of eicosapentaenoic acid (2.36%). Among the various solvents used, ethanol at 80% extracted the highest amounts of phenols and flavonoids that were 38.27 mg gallic acid equivalent and 17.69 mg catechin equivalent g−1 of dried extract, respectively. Using various in vitro assays including DPPH and ABTS radicals methods, reducing power assay, and β-carotene bleaching assay, the 80% ethanolic extract showed high antioxidant activity. A strong antibacterial activity was checked against Gram-positive bacteria (Staphylococcus aureus and Micrococcus luteus) and Gram-negative bacteria (Klebsiella pneumoniae and Salmonella enterica). These results are in favor of Amphora sp. valorization in aquaculture and food and pharmaceutical industries.
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Khumaidi, A., A. Muqsith, A. Wafi, U. Mardiyah, and L. Sandra. "Phytochemical screening and potential antioxidant of Amphora sp. in different extraction methods." IOP Conference Series: Earth and Environmental Science 1221, no. 1 (August 1, 2023): 012056. http://dx.doi.org/10.1088/1755-1315/1221/1/012056.
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Abstract Character of Amphora sp., has a golden brown color with bioactives such as photosynthetic pigments which have important biological functions for health. This study aims to determine the method of Amphora sp. extraction which is more effective and efficient in producing qualitative and quantitative bioactive, as well as the best antioxidant activity. Amphora sp., extracted with absolute ethanol solvent using different extraction methods, namely sonication (SON), maceration (MAS), and sonication-maceration (SON-MAS). The sonication method showed more effective and efficient results with yield value. The results showed that the SON-MAS method produced the highest yield of 9.8% compared to MAS 8.71% and SON 8.47%. The highest chlorophyll content was seen in the MAS method, total chlorophyll 2.36 ± 0.07 mg/l. Phytochemical content of the SON-MAS and SON methods contained flavonoids, alkaloids, and triterpenoids, while the MAS method showed two compounds, namely alkaloids and triterpenoids. Quantitatively, the phenol and flavonoid content showed that the SON method had a higher value, namely phenol and flavonoids. The best DPPH free radical scavenging antioxidant activity was seen in the SON method with an IC50 value of 745.2 ppm. The extraction method by sonication is considered to have effectiveness and efficiency in producing bioactive Amphora sp.
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Dias, Nicolina, David Mota, Ana Nicolau, and Manuel Mota. "Monitoring Amphora sp. growth by flow cytometry." Diatom Research 33, no. 3 (July 3, 2018): 405–11. http://dx.doi.org/10.1080/0269249x.2018.1523231.
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Barokah, Giri Rohmad, Ajeng Kurniasari Putri, and Gunawan Gunawan. "Kelimpahan Fitoplankton Penyebab HAB (Harmful Algal Bloom) di Perairan Teluk Lampung pada Musim Barat dan Timur." Jurnal Pascapanen dan Bioteknologi Kelautan dan Perikanan 11, no. 2 (March 21, 2017): 115. http://dx.doi.org/10.15578/jpbkp.v11i2.302.
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Telah dilakukan penelitian tentang analisis kelimpahan fitoplankton penyebab HAB (Harmful Algal Bloom) di Perairan Teluk Lampung pada musim barat dan musim timur. Penelitian ini bertujuan untuk mengidentifikasi alga yang berpotensi menyebabkan HAB yang berada di Teluk Lampung dan melihat pola hubungan kelimpahan fitoplankton yang bepotensi menyebabkan HAB dengan nutrien yang terkandung di perairan Teluk Lampung, Kab. Pesawaran, ProvinsiLampung. Pengambilan sampel dilakukan pada musim timur (April) dan musim barat (Oktober) pada tahun 2015. Dari penelitian ini ditemukan bahwa pada musim timur fitoplankton yang teridentifikasi dan berpotensi menyebabkan HAB adalah Amphora sp., Nitzchia sp., Ceratium sp., Dynophisis sp., Gymnodinium sp., dan Nocticulla scintillans. Pada musim barat fitoplankon yang teridentifikasi dan berpotensi menyebabkan HAB adalah Amphora sp., Nitzchia sp., Pseudonitzchia sp.,Alexadrium sp., Ceratium sp ., Cochlodium polykiroides, Dhynophisis sp ., Gambirdiscus toxicus, Gymnodinium sp., Nocticula scintillans, Procentrum sp., Pyrodinium bahamase dan Peridinium sp. Pada musim timur kelimpahan fitoplankton penyebab HAB yang terdapat di perairan Teluk Lampung didominasi oleh spesies Ceratium sp. dengan rata-rata 1,802 ind/L sedangkan pada musim barat kelimpahan fitoplankton di Teluk Lampung didominasi oleh Nitczchia sp ., dengan rata-rata kelimpahan 161,207ind/L.
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ZIDAROVA, RALITSA, MARGAUX POTTIEZ, PLAMEN IVANOV, MYRIAM DE HAAN, and BART VAN DE VIJVER. "Amphora micrometra Giffen and Halamphora valdeminutissima sp. nov., two tiny benthic diatom species observed in the Black Sea." Phytotaxa 626, no. 3 (November 23, 2023): 199–207. http://dx.doi.org/10.11646/phytotaxa.626.3.6.
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During a survey of the diatom flora present on an artificial substratum (plexiglass) submerged off the southern Bulgarian Black Sea coast, a small-celled diatom taxon, reported previously from the Black Sea as Amphora (Halamphora) sp. S21, was observed. Detailed light and scanning electron microscope observations showed that the original taxon actually included two different taxa: an unknown Halamphora species described here as H. valdeminutissima sp. nov., and a second taxon, which, based on SEM observations, could be identified as Amphora micrometra Giffen. The morphology of both taxa is described in detail and a comparison with similar taxa is provided. Additionally, environmental data of the habitat is also provided.
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Kwon, Hyeong-Kyu, Han-Soeb Yang, Yeoung-Moon Yu, and Seok-Jin Oh. "Effects of Substrate Size on the Growth of 4 Microphytobenthos Species (Achnanthes sp., Amphora sp., Navicula sp. and Nitzschia sp.)." Journal of Environmental Science International 21, no. 1 (January 31, 2012): 105–11. http://dx.doi.org/10.5322/jes.2012.21.1.105.
Full textDissertations / Theses on the topic "Amphora sp"
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Arnaldo, Mary. "Eco-physiological study of the marine benthic diatom Amphora sp. : optimization of culture conditions for health, cosmetic and food applications." Electronic Thesis or Diss., Nantes Université, 2023. http://www.theses.fr/2023NANU4037.
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Les diatomées benthiques marines ont la capacité de produire une biomasse de qualité et des composés bioactifs pour diverses applications commerciales. Amphora sp. NCC169 est l'une de ces espèces qui produisent des lipides de grande valeur. Cependant, la production de masse d Amphora sp. NCC169 dans un photobioréacteur traditionnel à suspension est rendue difficile par sa sensibilité à l'agitation et aux turbulences. Des cultures d’ Amphora sp NCC169 ont été mise en place au sein d’un phtobioréac teur de substrat poreux (PSBR) à orientation verticale afin de produire de la biomasse et des lipides. Les résultats ont été comparés à ceux obtenus par une technique plus classique de culture en batch dans des fioles de type Fernbach. Il apparaît une productivité de croissance (P biomasse = 0.5 ± 0.03 g·m 2 ·j 1 ) et une production de lipide (P lipide = 0.10 ± 0.02 g· m 2 ·j 1 ) plus importante en PSBR. L'étude a également démontré l'impact positif d'une combinaison de longueurs d'onde de lumière rouge (620 780 nm) et bleue (440 490 nm) sur le taux de production de lipides d' Amphora sp. NCC169 en utilisant le PSBR (23,8 ± 2,3 %). Cette recherche met en exergue le succès des cultures en biofilm, et souligne l’importance de respecter la physiologie des Diatomées benthiques afin de générer de la biomasse et des lipides d’intérêtMarine benthic diatoms have the capacity to produce quality biomass and bioactive compounds for various commercial applications. Amphora sp. NCC169 is one of such species that have high-value lipid production. However, mass-production of Amphora sp. NCC169 in traditional suspension photobioreactor is challenged by its sensitivity to stirring and turbulence. Cultures of Amphora sp. NCC169 were set up in a vertically oriented porous substrate photobioreactor (PSBR) to produce biomass and lipids. Results were compared with those obtained using a more conventional batch culture technique in Fernbach-type flasks. Growth productivity (Pbiomass = 0.5 ± 0.03 g·m-2·day-1) and lipid production (Plipid = 0.1 ± 0.02 g·m-2·day-1) were higher in PSBR. The study also demonstrated the positive impact of a combination of red (620 - 780 nm) and blue (440 - 490 nm) light wavelengths on the lipid production rate of Amphora sp. NCC169 using PSBR (23.8 ± 2.3%). This research highlights the success of biofilm cultures and underlines the importance of respecting the physiology of benthic diatoms in order to generate biomass and lipids of interest
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Shiu, Cheung Chi, and 張繼修. "Growth and Adhesion of Three Marine Diatoms─ Amphora sp., Nitzschia sp. and Entomoneis sp." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/93968943755796902040.
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碩士國立海洋大學
水產養殖學系
87
The purpose of this research was to gather basic information about initial attachment and growth in fouling diatoms found in Keelung Harbor. First, we establish cultures of 3 fouling diatoms from Pa-tsu-men (Amphora sp., Nitzschia sp. and Entomoneis sp.). We established their growth and attachment characteristics under different temperature (15℃, 20℃, 25℃, 30℃) and nitrate (0mM, 0.4mM, 0.8mM) conditions. In order to determine what kind of chemical was involved in attachment we added inhibitors for protein (cycloheximide), glycoprotein (tunicamycin) and sulphated polysaccharides (sodium molybdate) . Free-floating stages were introduced into the culture medium we identified as ideal with the addition of the different inhibitors, each at 5 concentrations. Without inhibitors, the attachment rate was 55-60%. Each inhibitor reduced attachment. Minimum attachment varied from 15-25%. For each genus there was a cutoff concentration where addition of the inhibitor made no difference. Four trials with each of the genera and each of the inhibitors were then set up to see the effect of the addition of cutoff concentration inhibitor at different times in the settling and attachment process (0hr, 3 hr, 6hr, 12 hr). In all cases, the earlier the inhibitor was added, the poorer the attachment. A further experiment involved moving attached diatoms into 7 cultures with enzymes added (3 for proteins, 4 for carbohydrates). This was done to further clarify which kinds of chemical components were involved in attachment. Ampohra sp. attachment was reduced by α-chymotrypsin and papain. Nitzschia sp. was reduced by α-mannosidase and papain. Entomoneis sp. was reduced by α-mannosidase and protease. The final set of experiments was done to see if they type of settlement plate affected attachment. We used 9 types of plates, 1 hydrophilic (glass coverslip) 6 intermediate ( steel, polyethylene, polystyrene, low-density polyethylene, Na-ionomer, Zn-ionomer ) and 2 kinds of hydrophobic (RTV and teflon). In terms of growth, there was no affect. However, attachment was greatly affected. On glass plates, regardless of the diatom used, attachment was between 60-68.5%. However, attachment rates on teflon were reduced to 8-22%.
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Chen, Guan-Quan, and 陳冠全. "Growth of Navicula sp. and Amphora sp. at different temperatures and light densities, and the survival of small abalone Haliotis diversicolor supertexta spat supplied with these algae." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/47610172279682595871.
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碩士國立臺灣海洋大學
水產養殖學系
92
Abstract This experiment was conducted to find out the survival and growth of small abalone Haliotis diversicolor supertexta fed two different types of diatoms Navicula sp. and Amphora sp. Two diatoms were isolated from abalone farm. The growth of the diatom grown at different temperatures of 15, 20, 25 and 30 ℃ and under three different light densities of 1000, 2000, and 3000 lux were studied. The number of diatoms increased with temperature and light density. The division rate of Navicula sp. at 30 ℃ was 4.2 and 4.5 times than that at 15 ℃ under 3000 and 1000 lux, respectively. The division rate of Amphora sp. was at 4.3 and 4.3 times higher at 30 ℃ than at 15 ℃ under 3000 and 1000 lux, respectively. The highest division rate was 1.67 div/day for Navicula sp. and 1.31 div/day for Amphora sp., respectively under 3000 lux at 30 ℃. Survival of small abalone spat fed Navicula sp., Amphora sp. and without supply of algae (without added diatom) at 15, 20, 25 and 30 ℃ were studied. The survival of spat fed Navicula sp. was 0, 13.2, 13.9 and 12.0 % at 15, 20, 25 and 30 ℃, respectively. No significant difference in survival rate was observed for the small abalone spat fed Amphora sp. among different temperatures. Survival of abalone spat fed Navicula sp. was the highest, among three treatments. The survival rate of abalone fed Navicula sp. and Amphora sp. was 13.9 % and 1.3 %, respectively at 25 ℃. The number of spat on the corrugated roofing plastic sheet was 25, 28 and 16 for the abalone spat fed Navicula sp. at 20, 25 and 30 ℃, respectively, after 25 days. However, the number of spat on the plastic sheet was 1, 3 and 1 for the abalone spat fed Amphora sp. at 20, 25 and 30 ℃, respectively after 25 days. Survival and growth of small abalone spat were studied. After 45 and 60 days of culture periods, the number of spat was 42 and 70 per sheet, for the first and second trial, respectively. Additional algae of Navicula sp. and Amphora sp. were supplied. The spat grew to 0.36 ～ 1.24 cm and 0.28 ～ 0.61 cm with an average of 0.72 and 0.38 cm, after 60 and 45 days, for the first and second trial, respectively. The spat developed pink red and the survival was 14 %. Therefor, it is suggested that artificial supply of diatoms like Navicula sp. and Amphora sp. could improve the growth of abalone spat and increase the survival rate.
Book chapters on the topic "Amphora sp"
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M, Koperuncholan, Ramesh T, and Muruganantham P. "Diatom of Interest as Food Source: Biochemical Composition of Hydrographic, Seasonal Diversity, Distribution and Abundance in Pamban Area of Gulf of Mannar, Tamil Nadu, India." In Emerging Food and Bioscience Research on Human Health: Safety, Security and Sustainable Aspects, 73–88. Skyfox Publishing Group, 2023. http://dx.doi.org/10.22573/spg.023.978-93-90357-85-7/5.
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In this study, 62 species of diatoms were identified. Spatio-temporal analysis of diatom community composition revealed that Amphora lineata Gregory, Amphora ovalis (Kutzing), Amphora proteus Gregory, Bacteriastrum hyalinum var. Princeps (Castracane) Ikari, Cyclotella striata (Kutz), Grun. Mastogloya Arabica, navicula sp, and surirella armoricana were the main species observed during the study period. A study was conducted to identify the abundance of diatoms and environmental factors that affect the growth of diatoms in the region and to identify major changes in diatom species according to seasonal changes. Community analysis revealed that diversity, abundance, uniformity and low winter season while dominance were pre-monsoon. In this record non-quantitative multidimensional scaling method (MDS) of the Bray-Curtis ordination, the highest similarity (82.55%) was observed for the abundance of diatoms at observation sites 2 and 3 before and after the 2014 monsoon. 1, Art. The similarity for Monsoon 3 in 2015 was the lowest at 16.32%. Comparison of our results with previous studies revealed that nitrate and ammonia are the main factors that have the greatest influence on diatom distribution. Community structure studies have shown that the pre-monsoon and monsoon season are most favorable for diatom production in the Pamban region of Mannar Bay.
Conference papers on the topic "Amphora sp"
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Bekova, Radoslava, and Bogdan Prodanov. "FOOD SPECTRUM OF THREE FISH SPECIES FROM THE MUGILIDAE FAMILY IN BRACKISH WATER ALONG THE BULGARIAN BLACK SEA COAST." In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/5.1/s20.025.
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The food spectrum of three fish species from the Mugilidae family in different age groups was studied. The samples were collected in 2019 - 2021 from the river estuaries and the coastal brackish lakes at the Bulgarian Black Sea coast. The research aims to establish the food spectrum of mullets and thus make a connection between food components. The results show that the predominant groups in the stomachs of the three mullet species are detritus, zoobenthos (Rissoa sp. And Trochammina inflate - 64.28%) and macrophytes (Cladophoraceae family - 53.14%). Several potential toxic species were also found: Amphora coffeaeformis, Pseudo-nitzschia delicatissima, Pseudonitzschia seriata, Prorocentrum cordatum, E. pyriformis, P. minimum, Protoperidinium crassipes. For the first time along the Bulgarian Black Sea coast, in the stomachs of mullet fish, the presence of particles (less than 2.5 cm) from the category "Artificial polymers" was observed. The most common in the stomachs of mullet are macrophytes of the family Ulvaceae - 45.5%; family Cladophoraceae - 35.5%; from phytoplankton - Navicula spp (97.09%); of zoobenthos: Nematoda g.sp. - 49.3% and Trochammina inflate - 32.3%.
Reports on the topic "Amphora sp"
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Shpigel, Muki, Allen Place, William Koven, Oded (Odi) Zmora, Sheenan Harpaz, and Mordechai Harel. Development of Sodium Alginate Encapsulation of Diatom Concentrates as a Nutrient Delivery System to Enhance Growth and Survival of Post-Larvae Abalone. United States Department of Agriculture, September 2001. http://dx.doi.org/10.32747/2001.7586480.bard.
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The major bottlenecks in rearing the highly priced gastropod abalone (Haliotis spp.) are the slow growth rate and the high mortality during the first 8 to 12 weeks following metamorphosis and settling. The most likely reason flor these problems is related to nutritional deficiencies in the diatom diet on which the post larvae (PL) feed almost exclusively in captivity. Higher survival and improved growth rate will reduce the considerable expense of hatchery-nursery resisdence time and thereflore the production costs. BARD supported our research for one year only and the support was given to us in order to prove that "(1) Abalone PL feed on encapsulated diatoms, and (2) heterotrophic diatoms can be mass produced." In the course of this year we have developed a novel nutrient delivery system specifically designed to enhance growth and survival of post-larval abalone. This approach is based on the sodium-alginate encapsulation of heterotrophically grown diatoms or diatom extracts, including appetite-stimulating factors. Diatom species that attract the PL and promote the highest growth and survival have been identified. These were also tested by incorporating them (either intact cells or as cell extracts) into a sodium-alginate matrix while comparing the growth to that achieved when using diatoms (singel sp. or as a mixture). A number of potential chemoattractants to act as appetite-stimulating factors for abalone PL have been tested. Preliminary results show that the incorporation of the amino acid methionine at a level of 10-3M to the sodim alginate matrix leads to a marked enhancement of growth. The results ol these studies provided basic knowledge on the growth of abalone and showed that it is possible to obtain, on a regular basis, survival rates exceeding 10% for this stage. Prior to this study the survival rates ranged between 2-4%, less than half of the values achieved today. Several diatom species originated from the National Center for Mariculture (Nitzchia laevis, Navicula lenzi, Amphora T3, and Navicula tennerima) and Cylindrotheca fusiformis (2083, 2084, 2085, 2086 and 2087 UTEX strains, Austin TX) were tested for heterotrophic growth. Axenic colonies were initially obtained and following intensive selection cycles and mutagenesis treatments, Amphora T3, Navicula tennerima and Cylindrotheca fusiformis (2083 UTEX strain) were capable of growing under heterotrophic conditions and to sustain highly enriched mediums. A highly efficient selection procedure as well as cost effective matrix of media components were developed and optimized. Glucose was identified as the best carbon source for all diatom strains. Doubling times ranging from 20-40 h were observed, and stable heterotroph cultures at a densities range of 103-104 were achieved. Although current growth rates are not yet sufficient for full economical fermentation, we estimate that further selections and mutagenesis treatments cycles should result in much faster growing colonies suitable for a fermentor scale-up. As rightfully pointed out by one of the reviewers, "There would be no point in assessing the optimum levels of dietary inclusions into micro-capsules, if the post-larvae cannot be induced to consume those capsules in the first place." We believe that the results of the first year of research provide a foundationfor the continuation of this research following the objectives put forth in the original proposal. Future work should concentrate on the optimization of incorporation of intact cells and cell extracts of the developed heterotrophic strains in the alginate matrix, as well as improving this delivery system by including liposomes and chemoattractants to ensure food consumption and enhanced growth.