Evaluation of the antioxidant activity of dried (rehydrate) and fresh sea cucumber, Holothuria parava

Sea cucumber is a valuable resource containing several materials that can be used as natural products and pharmaceutical industries. In this study, proximate composition and the amount of total phenols, flavonoids and antioxidant activity of fresh and rehydrated (after drying) sea cucumber, Holothuria parva, were examined. The samples were collected from Bandar Lengeh in the Persian Gulf during low tide and kept frozen. The samples were freeze-dried and the moisture content was calculated. The protein, lipid, ash and carbohydrate contents were then measured. The amounts of antioxidant activity (DPPH), phenol and flavonoid contents were also measured. All results have possibility (p<0.05). In fresh sample, the moisture, protein, lipid, ash and carbohydrate contents were 81.20, 12.00, 0.34, 5.50 and 0.95%, respectively, while they were 92.50, 3.76, 0.36, 1.00 and 2.07% in rehydrated sample. The antioxidant activity in fresh and rehydrated samples were equal to 0.063 and 0.060 mg vitamin C/g dry sample, respectively. The IC50 in fresh sample was 5.26 while in the rehydrated sample was 4.14. Total phenol content of fresh and rehydrated samples were equal to 0.22 and 0.19 mg gallic acid/g dry sample, repectively. The flavonoid contents in fresh and rehydrated samples were equal to 3.86 and 5.02 mg Quercetin/g dry sample, respectively. The amounts of protein and ash in fresh sample were significantly higher than rehydrated sample with significant difference (p<0.05). Moisture in rehydrated sample was significantly higher than fresh sample with significant difference (p<0.05). There were no significant difference between fresh and rehydrated samples in terms of their phenon and flavonoid contents. The DPPH radical scavenging capacity was significantly higher in the fresh sample compared to the rehydrated sample with significant difference(p<0.05). It can be concluded that this species of fresh sea cucumber has more antioxidant activity than rehydrated (after drying) sea cucumber and more beneficial to be used in pharmaceutical and food industries

Effects of different temperature profiles and corn-sago starch ratios on physical properties of extruded tilapia diets

Sago starch is a locally grown and produced starch resource in Malaysia. In this study, corn starch to sago starch ratios (CS:SS) of 0:20, 5:15, 10:10, 15:5 and 20:0 were included in feed mixture to contain 20% starch and produce five isonitrogenous and isocaloric (30% crude protein and 16.7 kJ/g, respectively) tilapia Oreochromis sp. diets. Diets were preconditioned to contain 40% moisture and extruded using a single-screw extruder at screw speed of 120 rpm using three different temperature profiles (I 60-100-140-180˚C; II 60-100-120-160˚C; and III 60-120-120-180˚C). Effects of these factors were evaluated on physical properties of extrudates including expansion ratio, bulk density, water stability, floatability, sinking velocity and durability. From the results, different temperature profiles and CS:SS had significant effects (p<0.05) on expansion ratio and floatability. Sago starch performed as a good binder as it gave higher percentage of water stability and pellet durability. The mixture with 10:10 of corn to sago starch extruded using temperature profile II (60-100-120-160˚C) produced the best extrudates with desirable physical properties

Effects of varying dietary protein level on the growth, feed efficiency and body composition of lemon fin barb hybrid fingerlings

This study was conducted to determine the optimal dietary protein requirement for lemon fin barb hybrid fingerlings. Triplicate groups of fish (1.00 ± 0.05 g) were fed twice a day until apparent satiation with five isocaloric (16 kJ/g) diets containing varying protein level ranging from 20 to 40% for 60 days. Survival was not affected by the dietary protein level. The weight gain and specific growth rate were improved with dietary protein level up to 35 %. The best feed conversion ratio (1.61) was achieved at 35% dietary protein level. Protein efficiency ratio was not influenced by the dietary protein level. Using a broken line regression model, the dietary protein requirement of lemon fin barb hybrid was estimated at 34.6 % based on weight gain response but the value was not significantly better than the 30% protein diet. Proximate composition of the fish showed that dietary protein level only affected the protein content of the lemon fin barb hybrid. The study showed the protein retention was increased until 30% and decreased above this level. Lipid retention decreased as the dietary protein increased. It can be concluded that lemon fin barb hybrid required 30-35% protein at gross energy 16 kJ/g for the best growth and feed efficiency

Probiotic administration of Litopenaeus vannamei: Is there any negative effect on the fatty acid profile of meat?

It has been found that appropriate probiotic applications increased growth performance and disease resistance in shrimp. Bacillus subtilis has been suggested as a potent probiotic in improving growth performance and enhancing immune response in white shrimp, Litopenaeus vannamei. The aim of this work was to evaluate the possible effect of B. subtilis administration on the meat fatty acid profile of white shrimp, L. vannamei. Two groups of shrimps received B. subtilis strains L10 and G1 from the B. subtilis-supplemented feed (10^5 and 10^8 CFU g^-1) while two other groups received it from the rearing water (10^5 and 10^8 CFU ml^-1). One group received no B. subtilis and served as control. According to the results, there was no significant difference between the muscle fatty acid profiles of shrimps administrated by probiotic and control group. This study showed that B. subtilis administration, in either diets or water, did not have any negative effect on fatty acid profiles of L. vannamei meat

An investigation of ontogenic development of mouth and its size in larval and juvenile of Vimba vimba

In this study, mouth morphological development and the importance of size of pellet food at the onset of exogenous feeding, with respect to mouth size from hatching through 60s day after hatching (DAH), were studied in larval and juvenile Vimba bream (Vimba vimba). The samples were randomly taken at 1-8 DAH, then with 2, 5, and 10 days intervals until 60 DAH (being released into the sea). Morphological examinations of mouth were followed using SEM. The lengths of upper and lower jaws as well as the size of mouth gap at 45° and 90° were calculated to estimate the size of pellet food. The larval mouth opened at 1 DAH and filiform papillae, and lips began to form at 2 DAH. The first taste buds developed at 3 DAH. The larval mouth developed a crescent shape at 4 DAH and the structure of papilla became clear. A number of neuromast cells were observed around the mouth at 8 DAH. Finally, it can be concluded that with the onset of exogenous feeding, Vimba vimba larvae is probably able to ingest and digest 110 µm pellet food since 8 DAH. Thus, since 20 DAH until the end of larval rearing period, formulated diets can only be used

The effect of different cooking methods on fatty acid composition and antioxidant activity of n-3 fatty acids fortified tilapia meat with or without clove essential oil

Tilapia farmers are increasingly relying on dietary fish oil alternatives which substantially reduces health beneficial n-3 polyunsaturated fatty acids (PUFA) in tilapia products.? This may be further exacerbated depending on the cooking method.? This study aimed to evaluate the effects of different cooking methods on the fatty acid composition and oxidative stability of tilapia minced meat after prior fish oil fortifications with or without clove essential oil. Results showed that frying tilapia in either sunflower or palm oil significantly increased the saturated fatty acid and linoleic acid content, respectively, of tilapia. However, fish oil fortifications significantly increased the n-3 PUFA content, but tended to decrease oxidative stability, particularly when microwaving. This was mitigated by clove essential oil, which significantly improved oxidative stability after cooking. Results indicate that n-3 PUFA and clove essential oil fortifications is an effective method to deliver and protect these beneficial fatty acids for human consumers

Effects of crude methanol extract of Euphorbia hirta on Hematological and Biochemical indices and histological changes of liver in African Catfish Clarias gariepinus (Burchell, 1822).

Methanol extract of Euphorbia hirta was tested in in vivo experiment to investigate the effect on hematological and biochemical indices and histological changes of liver in the African catfish (Clarias gariepinus). The plant methanol extract was included in the feed and administered to the fish. The experiment was conducted for eight weeks and with five diets including control (E. hirta-0), 2 (E. hirta-2), 5(E. hirta-5), 7(E. hirta-7) and 9(E. hirta-9) g E. hirta kg-1 of dry matter diet. Fish fed the E. hirta-9 diet had lowest (p<0.05) RBC and TP compared with the other dietary groups. Histological analyses revealed this group (E. hirta-9) had histopathologic alterations in the liver. Results of this study indicated that methanol extract of E.hirta by 7 g kg-1 can be safely used to improve hematological indices of African catfish without any adverse effect on the liver