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In this research enzymatic hydrolysis of rice bran protein concentrate (RBPC) and soybean Protein (SBP) as control were studied with 3 commercial enzymes (Alcalase®, Papain and acommercial 3-enzyme cocktail containing of 1.6 mg ml − 1 Trypsin, 3.1 mg mlChymotrypsin, 1.3 mg ml −1 Aminopeptidase (SIGMA P7500) and 7.95 mg ml −1 pronase type XIV (SIGMA P5147) by the pH stat method. The hydrolysis was carried out at temperature of 28 C, 60 min and pH 8.00. Results were showed that RBPC, and SBP had higher Degree h y d r o l y s i s ( D H % ) w i t h A l c a l a s e ® e n z y m e . Alcalase®had stronger capability for hydrolysis compared to the other tested enzymes. After 60 minute of hydrolysis time, the DH% of Alcalase® for RBPC and SBP was 12.69 and 12.50 %, respectively. In contrast, papain enzyme was showed lowest DH% in three substrates that 1.56 and 1.24 % were for SBP and RBPC, respectively.The hydrolysis of the protein fraction performed the three enzymes on the two substrates was followed in SDS-PAGE. RBPC and SBP showed almost complete digestion with Alcalase® enzyme after 60 minutes. 3-enzyme cocktail enzyme hydrolyzed better the RBPC than the SBP. Papain enzyme had less effect on the two substrates than other 2 enzymes. It was found that Alcalase® has highest capability for hydrolysis compared to other enzyme preparations. The high value protein hydrolysates prepared by Alcalase® can be used as value added ingredients in many food formulations. They are also suitable for a broad range of industrial food applications and also for cosmetic and personal care products.

The larvae of the Pacific white shrimp Litopenaeus vannamei are fed, from the stage of protozoea I until to protozoea III (PZ III), with microalgae. The survival rate, duration of the terms of Z I -Z III and total length of protozoea larvae (PZ) of L. vannamei were survived. The shrimp larvae fed with the six treatments of microalgae (Chaetoceros muelleri, Isochrysis galbana, Tetraselmis tetrathele, C. muelleri : I. galbana, C. muelleri: T. tetrathele and I. galbana: T. tetratheie). The biochemical composition (protein, carbohydrate, lipid and energy) of the algae and the larvae fed those algae were also measured. The largest sizes were recorded for larvae fed with the mixture C. muelleri and I. galbana (4.35 mm) and smaller sizes were observed on larvae fed with I. galbana (3.04 mm) (P \ 0.05). The larvae fed with mixture T. tetrathele and C. muelleri (88.42 %) and I. galbana and T. tetrathele (84.50 %) had the highest survival in experimental treatments. The lowest time for development was observed in larvae fed with mixture of T. tetrathele and C. muelleri (92.6 h). The larvae fed with mixture I. galbana and T. tetrathele had the highest protein and carbohydrate levels as compared with other treatments. Also highest lipid level and gross energy were shown in larvae fed with mixture C. muelleri and I. galbana (P \ 0.05). The results showed that L. vannamei larvae fed with C. muelleri and the mixed diets containing this species (C. muelleri ? Isochrysis sp., C. muelleri ? Tetraselmis sp.) had the highest growth and survival among treatments.

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The effects of feeding on a commercial diet and lecithin‐enriched (EN) Artemia franciscana nauplii for improving co‐feeding strategies of Neotropical green terror cichlid (Aequidens rivulatus) larvae were conducted. For this purpose, eight groups of fish in triplicates were assigned with two different diets (unenriched Artemia [UN] and EN Artemia) and four feeding regimes (1, 5, 10 and 25 days feeding with UN and EN diets and then a 10% daily replacement Artemia nauplii with commercial diet). The crude lipid (21.4%) and total polar lipid (12.96% of total crud lipid) levels significantly increased in enriched Artemia nauplii (p < 0.05). The highest amount of saturated fatty acids (SFA) were in enriched and UN Artemia nauplii (41.74% and 49.64% respectively) but the highest level of monounsaturated fatty acids (MUFA) (25.69%) and polyunsaturated fatty acids (PUFA) (49.11%) were obtained in commercial diet. Growth performance of fish fed 10 EN and 5 EN had significantly higher values of total weight (120.67, 120.31 mg), %WG (584.48, 580.50%) and SGR (7.69, 7.67%) respectively (p < 0.05). Nevertheless, fish fed 25 EN had significantly higher FCE (190.4%), PER (3.95) and NPU (202.5), in comparison with other groups. In terms of body composition, the EN Artemia nauplii led to increased lipid contents in 25 EN, 10 EN and 5 EN treatments. In conclusion, the results of this study revealed that feeding regimes of 10 EN and 5 EN could improves survival and growth performance of Neotropical green terror cichlid, A. rivulatus larvae.

As algae and their concentrations are important factors for mass culture of rotifer, two experiments were conducted to find the effects of two types of algae, Chlorella sp. and Scenedesmus obliquus, and three concentration of chosen algae (0.1 × 106, 1 × 106, and 10 × 106 cells/mL) on growth and fatty acid composition of freshwater rotifer, Brachionus calyciflorus. The result of the first experiment showed that the maximum density of rotifer was significantly higher when fed with Chlorella sp. (478 individuals/mL) than fed with S. obliquus (328 individuals/mL). Mean population growth rate (r) was 0.61 and 0.44 for rotifer fed with Chlorella sp. and S. obliquus, respectively. The amount of highly unsaturated fatty acid (HUFA) in rotifer fed with Chlorella sp. (3.32%) was relatively more than those fed with S. obliquus (2.65%). Then, Chlorella sp. was selected based on better performance. In the second experiment, the maximum rotifer density of 108 ± 8, 489 ± 47, and 493 ± 51 individuals/mL was reached after 5 d for the respective Chlorella sp. concentrations; at concentration of 10 × 106 cells/mL, the maximum density of 1820 ± 47 individuals/mL was obtained. Mean growth rate at mentioned concentrations was 0.18, 0.42, and 0.51/d, respectively. Increase in algal concentration was associated with a relative increase in HUFA and decrease in monounsaturated fatty acid.

The present study investigated the effects of soybean lecithin bioencapsulated in adult ARTEMIA FRANCISCANA and unenriched ARTEMIA in combination with an inert diet on digestive enzymes activity and reproductive perfor-mance in Aequidens RIVULATUS (green terror cichlid). Eight hundred and ten fish (3.1 ± 0.2 g) were randomly allotted into glass tank (80 L) and assigned to ten dietary treatments with 5 different levels (0, 25, 50, 75, and 100%) of either lecithin-enriched ARTEMIA (EA) or unenriched ARTEMIA (UA) over a period of 90 days. The amount of total polar lipid increased from 39.2% in the unenriched ARTEMIA to 43.7% in the lecithin-enriched ARTEMIA (P < .05). The fish fed with 50% EA had higher total weight, and total length compared with other groups (P < .05). The peculiar functions of total alkaline proteases, α-amylase, and lipase in green terror increased in the groups fed with lecithin-enriched ARTEMIA, compared to the un-enriched groups (P < .05). The highest total alkaline proteases activity was observed in the fish fed with 75% EA treatment. In comparison to the other groups, fish fed 100 and 0% levels of ARTEMIA replacement had significantly highest and lowest α-amylase ac-tivity values, respectively. Concerning reproductive performance, the highest average fecundity, egg diameter, egg weight, fertilization, hatching, and larval survival rates, as well as the lowest time between two spawning episodes, were obtained in fish fed 50% EA. In conclusion, this feeding strategy is advisable for a proper nu-tritional management of broodfish of green terror cichlid.

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