Nutritive value of guar and copra meal after fermentation with yeast Saccharomyces cerevisiae in the diet of Nile tilapia, Oreochromis niloticus.

Solid-state fermentation increases nutritional bioavailability of plant ingredients by reducing the antinutritional factors and complexity of the nutrients. The present experiment was conducted to replace fish meal (FM) with a mixture (3:1) of yeast fermented guar and copra meal (FGCM) in the diet of Nile tilapia. Five iso-nitrogenous (30% CP) and iso-lipidic (6% CL) diets were formulated replacing FM at 0% (FGCM0), 25% (FGCM 1), 50% (FGCM 2), 75% (FGCM 3), and 100% (FGCM 4) with FGCM mixture. Growth, nutrient utilisation, digestibility, digestive enzyme activity, haematological parameters, and antioxidant capacity were analysed in five treatments after a feeding trial of 75 days. Bioprocessing increased the protein and amino acid content and reduced the antinutritional factors in the guar and copra meal. The weight gain was significantly increased in 25% replaced diet. The feed conversion ratio of tilapia fed with FGCM 1 was similar to that of control and significantly lower (P < 0.05) among the treatments. The group fed with FGCM 1 exhibited significantly higher body protein and lipid content. The activity of digestive enzymes and digestibility of nutrients reduced significantly (P < 0.05) with the replacement of fishmeal beyond 25% with the FGCM mixture. Similarly, the antioxidant enzymes and blood parameters were also negatively affected when more than 25% FM was replaced with FGCM mixture. The cubic regression analysis found that 17.45% FM can be replaced with FGCM mixture for optimum weight gain in tilapia.

Changes in biogenic amines, biochemical and microbial attributes of three spotted crab (Portunus sanguinolentus) during iced and refrigerated storage.

Three spotted crab (Portunus sanguinolentus) is a preferred variety of crab among seafood consumers. Biochemical, microbial and sensory characters along with formation of biogenic amines of whole crabs stored under iced and refrigerated condition was evaluated. Cadaverine, putrescine and spermidine were the major amines formed during spoilage and a strong correlation between cadaverine and psychrotrophs was observed in refrigerated (0.92) and iced storage (0.86) respectively. Histamine was at lower level and not likely to cause any toxicological problems to consumers. Although TVB-N and TMA-N increased significantly (p < 0.01), TVBN was observed as a good indicator of spoilage than TMA-N. Mesophilic and psychrotrophic bacteria crossed 7 log CFU/g on 8th day, rejection day of refrigeration, while it was below spoilage limit in iced storage. A shelf life of 6 and 10 days were observed in storage under refrigeration and icing respectively based on microbiological, biochemical and sensory attributes.

Macromineral and heavy metal profiles of selected deep-sea fish from the Kochi coast of the Arabian Sea, India.

Deep-sea fish from the Arabian Sea in the south western coast of India have been gaining attention as a new edible fish source. Mineral profile of ten selected deep-sea fish from the south west coast of India were assessed for heavy metal and macro mineral content for safety and nutritional quality assessment, respectively. Heavy metal levels were below permissible limits for most of the species studied. But in some species, the levels slightly exceeded the permissible limit of 0.3 mg/kg for Pb, a major heavy metal contaminant in fish, according to the European Union and FSSAI regulations for heavy metals in food. Interestingly, significant content of macro minerals was observed in all the species studied. In conclusion, deep-sea fish were observed to be good source of minerals and were found to be safe for human consumption; except for a couple of species which possess slightly higher Pb content, which may be because of its presence in their habitat.

Identification of allergic proteins of Flower tail shrimp (Metapenaeus dobsonii).

Allergy to seafood mainly fish and shellfish has been reported. Tropomyosin is recognized as a major allergen in many crustaceans especially shrimps. A study was carried out to identify the IgE reactive proteins of allergic nature in Flower tail shrimp (Metapenaeus dobsonii), a frequently consumed shrimp in India mainly in dried form. Protein profiling and identification of IgE reactive proteins in raw and cooked extracts of Flower tail shrimp was carried out by SDS-PAGE and immunoblotting using sera of 13 patients having allergic reactions on consumption of shrimp and positive to skin prick test. The IgE binding ability was determined by ELISA and it was found higher in the case of cooked extracts ranging from 0.244 to 0.440 at 490 nm. The SDS-PAGE of raw extract revealed many protein bands between 205 and 6.5 KDa, while in the case of cooked extracts bands of 36, 20, 29 and 70 KDa were prominent. Heat resistant protein of 37 KDa, tropomyosin was showing a clear immune reaction both in the case of raw and cooked extracts was identified as the major allergen by all the patient sera. The minor proteins of raw extract identified by immune reaction are 50, 75 and 100 KDa. The identified allergen can be used for the diagnosis and management of shrimp allergy.

DHA and EPA Content and Fatty Acid Profile of 39 Food Fishes from India.

Docosahexaenoic acid (DHA) is the principal constituent of a variety of cells especially the brain neurons and retinal cells and plays important role in fetal brain development, development of motor skills, and visual acuity in infants, lipid metabolism, and cognitive support and along with eicosapentaenoic acid (EPA) it plays important role in preventing atherosclerosis, dementia, rheumatoid arthritis, Alzheimer's disease, and so forth. Being an essential nutrient, it is to be obtained through diet and therefore searching for affordable sources of these ω-3 polyunsaturated fatty acids (PUFA) is important for consumer guidance and dietary counseling. Fish is an important source of PUFA and has unique advantage that there are many food fish species available and consumers have a wide choice owing to availability and affordability. The Indian subcontinent harbors a rich fish biodiversity which markedly varies in their nutrient composition. Here we report the DHA and EPA content and fatty acid profile of 39 important food fishes (including finfishes, shellfishes, and edible molluscs from both marine water and freshwater) from India. The study showed that fishes Tenualosa ilisha, Sardinella longiceps, Nemipterus japonicus, and Anabas testudineus are rich sources of DHA and EPA. Promotion of these species as DHA rich species would enhance their utility in public health nutrition.

Micronutrient Composition of 35 Food Fishes from India and Their Significance in Human Nutrition.

The micronutrients (vitamins and minerals) are required in small amounts but are essential for health, development, and growth. Micronutrient deficiencies, which affect over two billion people around the globe, are the leading cause of many ailments including mental retardation, preventable blindness, and death during childbirth. Fish is an important dietary source of micronutrients and plays important role in human nutrition. In the present investigation, micronutrient composition of 35 food fishes (includes both finfishes and shellfishes) was investigated from varying aquatic habitats. Macrominerals (Na, K, Ca, Mg) and trace elements (Fe, Cu, Zn, Mn, Se) were determined by either atomic absorption spectroscopy (AAS) or inductively coupled plasma mass spectrometry (ICP-MS)/atomic emission spectrometry (ICP-AES). Phosphorus content was determined either spectrophotometrically or by ICP-AES. Fat-soluble vitamins (A, D, E, K) were analyzed by high-performance liquid chromatography (HPLC). The analysis showed that, in general, the marine fishes were rich in sodium and potassium; small indigenous fishes (SIFs) in calcium, iron, and manganese; coldwater fishes in selenium; and the brackishwater fishes in phosphorous. The marine fishes Sardinella longiceps and Epinephelus spp. and the SIFs were rich in all fat-soluble vitamins. All these recommendations were made according to the potential contribution (daily value %) of the species to the recommended daily allowance (RDA). Information on the micronutrients generated would enhance the utility of fish in both community and clinical nutrition.

Amino Acid compositions of 27 food fishes and their importance in clinical nutrition.

Proteins and amino acids are important biomolecules which regulate key metabolic pathways and serve as precursors for synthesis of biologically important substances; moreover, amino acids are building blocks of proteins. Fish is an important dietary source of quality animal proteins and amino acids and play important role in human nutrition. In the present investigation, crude protein content and amino acid compositions of important food fishes from different habitats have been studied. Crude protein content was determined by Kjeldahl method and amino acid composition was analyzed by high performance liquid chromatography and information on 27 food fishes was generated. The analysis showed that the cold water species are rich in lysine and aspartic acid, marine fishes in leucine, small indigenous fishes in histidine, and the carps and catfishes in glutamic acid and glycine. The enriched nutrition knowledge base would enhance the utility of fish as a source of quality animal proteins and amino acids and aid in their inclusion in dietary counseling and patient guidance for specific nutritional needs.

Effect of tetracycline on pancreas and liver function of adult male albino rats.

The effect of tetracycline, at two doses of 50 and 200 mg kg(-1) daily, was studied on pancreatic and liver tissue function for 14 and 21 days in adult male albino rats. For pancreatic function the parameters studied were content of amylase and lipase in pancreas, serum amylase and lipase, serum glucose and faecal fat excretion. For liver function, liver specific enzymes in serum, namely alanine amino transaminase, aspartate amino transaminase and lactate dehydrogenase were estimated. In addition, total lipid, antiperoxidative enzymes and lipid peroxidation were measured in pancreas and liver. The content of amylase and lipase in pancreas showed a small but significant decrease in the rats given 50 mg kg(-1) for 21 days and the decrease was much more significant in those receiving the 200 mg kg(-1) dose. In pancreas free radical levels show a significant increase and reduced glutathione shows a substantial decrease at the 50 mg kg(-1) level and a significant change in these parameters was observed at the 200 mg kg(-1) dose. Antioxidant enzymes, superoxide dismutase, glutathione peroxidase, glutathione reductase and catalase, showed a small but significant decrease in the pancreas of the rats treated with 50 mg kg(-1) tetracycline. A significant decrease in the antioxidant enzymes level was observed at the 200 mg kg(-1) dose. In the liver, free radical levels and reduced glutathione were within the normal range at the 50 mg kg(-1) level and significant changes were observed at 200 mg kg(-1). The antioxidant status was unaffected in liver after treatment with tetracycline at the 50 mg kg(-1) level and a significant decrease was observed at the higher dose. Our results reveal the safe nature of tetracycline with respect to the liver at the lower dose tested, whereas, both the higher and lower doses seem to have detrimental effect on the pancreas as revealed by the rise in free radical levels and decrease in the antioxidant enzyme levels.

Protective effect of n-3 polyunsaturated fatty acids concentrate on isoproterenol-induced myocardial infarction in rats.

The protective effect of PUFA concentrate prepared from fish oil on isoproterenol-induced myocardial infarction in male albino rats was investigated with respect to changes in the levels of diagnostic marker enzymes, cholesterol, triglycerides, free fatty acids, phospholipids, reduced glutathione (GSH) and lipid peroxides (LPO). Administration of PUFA concentrate significantly prevented the isoproterenol-induced elevation in the levels of plasma diagnostic marker enzymes (ALT [93.5%], AST [95.6%], LDH [94.7%] and CPK [96.1%]). PUFA concentrate feeding exerted a significant antilipidemic effect against isoproterenol-induced myocardial infarction by reducing the levels of lipid components in plasma (cholesterol [71.5%], triglycerides [79.7%] and free fatty acids [70.7%] and heart tissue (cholesterol [81.4%], triglycerides [76.3%] and free fatty acids [78.6%]). A tendency to prevent the isoproterenol-induced phospholipids depletion (74.4%) in the myocardium of experimental rats was also observed. The level of lipid peroxidation was also found to be significantly lower in PUFA treated animals (2.72+/-0.15nmol/ml in plasma; 1.18+/-0.08nmol/mg protein in heart tissue) as compared to that of isoproterenol-injected groups (5.77+/-0.43nmol/ml in plasma; 2.14+/-0.15nmol/mg protein in heart tissue) of rats. Also the level of reduced GSH significantly higher in the heart tissue of PUFA administered experimental rats (5.65+/-0.98 microg/g) as compared to myocardial infarction induced control rats (2.39+/-0.18 microg/g). The results of the present study indicate that the overall cardioprotective effect of PUFA concentrate is probably related to its ability to inhibit lipid accumulation by its hypolipidaemic property.

Distribution of organochlorine pesticides and heavy metal residues in fish and shellfish from Calicut region, Kerala, India.

Fish collected from five different locations from the Calicut region, India were analysed for the levels of organochlorine pesticides (OCPs) and heavy metal (HM) residues in order to elucidate the status of these chemical contaminants in fish and shellfish meant for human consumption. The highest concentrations of OCPs detected in the edible portion of fish were 10.47, 70.57 and 28.35 ng g-1 wet weight, in marine, brackish water and freshwater, respectively. BHC and heptachlor epoxide formed the major share of OCPs in the marine fish while BHCs contributed to the major share in the freshwater and brackish water fish. The DDT (sum of DDT and its metabolites) ranged from 0.05 to 8 ng g-1 in the samples irrespective of the habitat. Among the HMs, Cu, Zn, Mn and Cr were present in the samples irrespective of the place of collection. About 22% of the samples from the freshwater area contained marginally higher lead content above the legal limit of 0.2-0.4 microg g-1. The Cr content ranged from 0.1 to 1.1 microg g-1 in the fish with marginally higher content in the fish from freshwater and marine regions (0.55-1.1 microg g-1). Mercury was detected in the samples (55%) from marine habitat only. The concentrations of OCPs and HMs in the samples, in general, were below the maximum residual level recommended by various organizations.

Cardioprotective effect of squalene on lipid profile in isoprenaline-induced myocardial infarction in rats.

We studied the cardioprotective effect of squalene on isoprenaline-induced myocardial infarction in male albino rats with respect to changes in the levels of lipid components in plasma and heart tissue. Prior administration of 2% squalene in feed for 45 days significantly reduced the isoprenaline-induced elevation in the levels of cholesterol, triglycerides, and free fatty acids in plasma and heart tissue of rats following myocardial infarction. It exerted an antilipidemic effect by reducing the level of low-density lipoprotein cholesterol with a parallel rise in the level of high-density lipoprotein cholesterol in plasma of experimental rats. A tendency to prevent the isoprenaline-induced depletion of phospholipids in the myocardium of experimental rats was also observed. In the present study, the pretreatment with squalene significantly counteracted the isoprenaline-induced lipid peroxidation and maintained the rats at near normal status. The results of the present study indicate that the overall cardioprotective effect of squalene is probably related to an inhibition of lipid accumulation by its hypolipidemic properties and/or its antioxidant properties.

Effect of squalene on tissue defense system in isoproterenol-induced myocardial infarction in rats.

This study was designed to examine the effects of squalene on tissue antioxidant status in isoproterenol-induced myocardial infarction in male albino rats. Levels of diagnostic marker enzymes [alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and creatine phosphokinase (CPK)] in plasma, lipid peroxides, reduced glutathione, and the activities of glutathione-dependent antioxidant enzymes [glutathione peroxidase (GPx) and glutathione-S-transferase (GST)] and antiperoxidative enzymes [catalase (CAT) and superoxide dismutase (SOD)] in the heart tissue of experimental groups of rats were determined. The prior administration of squalene at 2% level along with feed for 45 days significantly prevented the isoproterenol-induced elevation in the levels of diagnostic marker enzymes in plasma of experimental rats. Squalene also exerted an antioxidant effect against isoproterenol-induced myocardial infarction by blocking the induction of lipid peroxidation. A tendency to prevent the isoproterenol-induced alterations in the level of reduced glutathione and in the activities of glutathione-dependent antioxidant enzymes and antiperoxidative enzymes was also observed. The cardioprotective effect of squalene might be ascribable to its antioxidant property and membrane stabilizing action.

Repeated use of oil for frying fish. Effects of feeding the fried fish to rats.

Four groups of weanling male albino rats (Wistar strain) were fed isonitrogenous diet (10% protein) identical in all respects except in the nature of the protein source, for 4 weeks. Control group (group 1) had steamed mackerel meat as the protein source, whereas groups 2, 3 and 4 had mackerel fried on the 1st, 3rd and 4th days in the same coconut oil repeatedly used for frying each day. Four groups of adult male rats weighing around 130 g were fed on the same diet for 12 weeks. Weanlings fed on fish fried on the 4th day showed significantly lower feed consumption and weight gain compared to the other three groups. All the three groups of adult rats fed on fried fish compared well with control rats in weight gain and hepatosomatic index. There was a decrease in the total lipid and cholesterol content of the liver of rats fed with fried fish in comparison with the control rats. The total lipid and cholesterol in heart and serum cholesterol levels increased significantly from control rats through group 4. The C22:6/C20:5 ratio in the heart lipid showed a very high value compared to the dietary lipids. Histopathological examination showed initial stages of cell damage in the liver and kidney of rats fed with fish fried on the 4th day. In-vitro digestibility of proteins of fried fish were lower than that of steamed fish, but the difference in this respect between proteins of fish fried on different days was not significant.