Biochemical investigations on edible molluscs of Kerala 1. A study on the nutritional value of some bivalves

Data on the biochemical constituents and food values of five commercially important edible bivalves of Kerala, Lamellidens corrianus, Corbicuta striatella, Mytilus edulis, Vellorita cohinensis and Ostrea cucullata have been presented. Physiological significance of the variations has been discussed. Present study reveals the bivalves meat compares favourably with the common food fishes with regard to their caloric value and hence would be an excellent and economic source of nutrition for our people.

Biochemical investigations on the edible molluscs of Kerala 2. A study on the nutritional value of some gastropods and cephalopods

Data on the biochemical composition and food value of the edible portions of two gastropods, Pila virens and Achatina fulica and two cephalopods, Sepiella inermis and Loigo indica have been presented. These molluscs possess nutritive meat very rich in protein and minerals, which compare favourably with popular food fishes in caloric value. The significance of the variations met with in the biochemical constituents of the different species has been discussed.

Oxidation of residual lipids in fish protein concentrates and its effect on the nutritional quality of the protein

The paper reviews the work reported on the changes in the nutritive value of fish protein concentrates (FPC) during, storage, with special emphasis on the effects of the interactions between oxidised residual lipids and proteins of the FPC. Theories on the oxidised lipid-protein interactions are reviewed and the nutritional significance of these reactions is discussed.

Studies on lantern fish (Benthosema pterotum) 2. Nutritional evaluation

Various methods for processing and utilization of lantern fish (Benthosema pterotum) are reported. Nutritional evaluation of fish meal and fish hydrolysate from lantern fish has been carried out. Growth rate and PER of lantern fish meal are similar and better than that of the reference protein, casein. Lantern fish meal can therefore be extensively used for the formulation of poultry, fish and other animal feeds as a good protein supplement with beneficial effects.

Nutritional evaluation of fish solubles

This paper reports the results of a preliminary study on the biochemical composition and nutritional charactersitics of fish solubles from oil sardines (Sardinella longiceps) and white tailed pink perch (Nemipterus japonicus). The nutritional quality of sardine solubles has been evaluated by feeding trials using albino rats also. The studies have shown that compared to a control group of rats whose diet had casein as the sole source of protein, a group of rats in whose diet dried sardine solubles replaced half of the casein, had a noticeably higher growth rate. This higher growth rate was not prominent in the early stages of growth (4-7 weeks). But, during later stages (7-10 weeks), solubles incorporated diet supported a distinctly higher growth rate. This effect was more pronounced in female rats (17% over the control group) compared to the male rats (4% over the control group). Fish solubles are found to be poor sources of essential amino acids. Thus, the observed increase in growth rate is higher than the rate expected from the amino acid make up. This probably supports the view expressed by workers elsewhere that fish solubles contain some unidentified growth factors.

Oxygen consumption under copper and zinc stress in Perna viridis

The rate of oxygen consumption by Perna viridis pre-exposed to copper and zinc was studied. Those test individuals pre-exposed to various zinc concentrations showed variability in oxygen consumption irrespective of concentrations and pre-exposure period. While those animals pre-exposed to various copper concentrations registered decrease in oxygen consumption at concentrations above 0.06 p.p.m. copper, pre-exposure to concentrations below 0.02 p.p.m. copper did not result in any clear cut change in the rate of oxygen consumption.

Nutritional evaluation of some freshwater fishes

The proximate composition, amino acid composition and the PER values of Rohu (Labeo rohita), Mrigal (Cirrhina mrigala) and Calbasu (Labeo calbasu) are reported. The proximate composition of all the three fishes was similar. However the amino acid composition varied considerably. Protein quality index of the three fish proteins calculated from the amino acid composition are also reported. The nutritional quality of the 3 types of proteins to meet the growth requirements of infants, children and adult human beings is discussed. The possibility of substantial improvement in nutritional quality of the three fish proteins to suit the requirements of infants and children by marginal supplementation with valine/valine-rich food for rohu and valine and isoleucine/food rich in valine and isoleucine for mrigal and calbasu is also discussed. The results indicate that of the three fishes rohu is the best in protein quality followed by mrigal and calbasu. All of them have a better amino acid make up than casein to meet the amino acid requirement of adults.

Nutritional evaluation of texturised meat from Nemipterus japonicus

Evaluation of the nutritional quality of texturised fish meat from threadfin bream (Nemipterus japonicus) is reported. Proximate composition and amino acid analysis showed that its protein content is very high with all the essential amino acids present in higher levels than those prescribed for man in the 1973 FAO/WHO amino acid scoring pattern. Lysine amounted to 11.0 g per 16 g N of which 75 percent is biologically available. Studies on PER and NPU also corroborate the excellent nutritional quality of the texturised meat.

Studies on the chemical and nutritional quality of protein powders isolated from shrimp waste

Protein powders were prepared from processing waste of prawns either by mechanically squeezing the shell and freeze drying the resultant aqueous extract or by treating the shell with 0.5% sodium hydroxide, filtering it and freeze drying the filtrate. Comparative studies on the proximate composition, amino acid profile, consumer acceptability and nutritional quality of the protein powders showed that the product prepared by freeze drying of the press liquor obtained by passing the waste through a hand operated expeller is better in all aspects studied than the product prepared by mild alkali extraction.

Both stress experience and age determine the impairment or enhancement effect of stress on spatial memory retrieval

It has been documented that stress or glucocorticoids have conflicting effects on memory under different conditions. However, it is not fully understood why stress can either impair or enhance memory. Here, we have examined the performance of six age groups of Wistar rats in a water maze spatial task to evaluate the effects of stress under different conditions. We found that the impairment or enhancement effect of an 'elevated platform' (EP) stress on memory was dependent on previous stress experience and on age. EP stress impaired memory retrieval in water maze naive animals. but enhanced rather than impaired memory retrieval in young water maze stress-experienced animals. Furthermore, exogenously applied corticosterone or foot shock stress before water maze training prevented the impairment of memory retrieval that should be induced by treatment with corticosterone or foot shock before the 'probe trial'. Again, memory retrieval was enhanced in young animals under these conditions, and this enhancement can be prevented by the glucocorticoid receptor antagonist RU 38486. Thus, glucocorticoid receptor activation not only induced impairment of memory but also increased the capacity of young animals to overcome a later stress. The present findings suggest that the effect of stress on memory can be switched from impairment to enhancement dependent on both stress experience and age.

Effects of irradiation on formaldehyde concentration and nutritional changes of formalin treated fish, Pampus chinensis

Formaldehyde is a very reactive compound capable of interacting with many functional groups of proteins including intermolecular and intramolecular cross-links of the molecules. The formation of cross-linking bonds may induce conformational change in proteins that favor further interaction of functional and hydrophobic groups. Formaldehyde which has been using illegally as a chemical preservative by some fish traders in our country. A study was carried out to determine the effects of irradiation (1.5 KGy) on formaldehyde concentration and nutritional (protein and lipid) changes of formalin (37% formaldehyde) treated fish (fresh) samples and found that the concentration of formaldehyde both in treated samples (0.37% formalin and 0.37% formalin with 1.5 KGy irradiation) were 37.0 µg/gm and 36.75 µg/gm. On the other hand, the amount of protein and lipid in treated samples before radiation (14.56% and 3.49%) and after radiation (14.15% and 3.25%). That means, radiation has no effect on the change of protein, lipid and formaldehyde.

Effect of paradoxical sleep deprivation and stress on passive avoidance behavior

Previous studies have shown that several types of stress can induce memory impairment. However, the memory effects of paradoxical sleep deprivation (PSD), a stressor in itself, are unclear. We therefore compared passive avoidance behavior of rats undergoing PSD and PSD stress yoked-control (PSC) using the "reversed flowerpot method." When rats were kept isolated on a PSC platform for 24 It immediately after criterion training, retention trials showed impaired aversive memory storage. When delayed for 24 h after criterion training, PSC stress did not disrupt retention performance. In rats subjected to PSD, either immediately or 24 It after criterion training, there was no disruption of aversive memory consolidation. These results suggest that, during stress, paradoxical sleep plays a role in erasing aversive memory traces, in line with the theory that we "dream in order to forget." (C) 2003 Elsevier Inc. All rights reserved.

Merging effects of vitamin E and C on biological factors, blood characteristics and resistance against thermal stress in rainbow trout (Onchorhyncus mykiss)

This study was conducted to assay the effects of different levels of dietary vitamins C and E on growth indices and survival and resistance against thermal stress of rainbow trout (Oncorhynchus mykiss) in pond culture of Marzan abad from December 2011 to February 2011. Seven diets were supplemented. 300 fish with the average weight of 17 g were introduced to ponds for 60 days. The results showed that the highest and the lowest weight gain were in fish fed with diet containing 50 mg/kg vitamin C and E and 0 mg/kg vitamin C and E(control) , respectively. The highest and the lowest Feed Conversion Ratio (FCR) were measured in control and diet 50 mg/kg vitamin C and E. There is a significant difference in their treatments (P<0.05). Also, the lowest and highest amount of Weight Gain (WG) were observed in (E) treatment with 165.04% and 117.5% in control, the highest and lowest Specific Growth Rate (SGR), Protein Efficiency Ratio (PER), Condition Factor (CF) was found in control and treatment 50 mg/kg vitamin C and E, respectively(P<0.05). In conclusion vitamin C and E have an important role in enhancement of growth performance and feed efficiency of rainbow trout.The highest red blood cells were found in combined treatments and which the vitamin C was added.The highest RBC were found in E treatment(1.1×104 /mm3) and the lowest one in control (P˂0.05). Counting white blood cells also confirmed highest quantity in combined treatments with (69.83×104/mm3) and the lowest one (28.83×104 /mm3) in control. In conclusion these vitamins have a significant role in blood characteristics. Meantime, the resistance against termal stress was measured at the end of 60 days by facing fishes into 5 centigrade warmer water so consentration of Cortisol and Glucose measured for this reason.The lowest cortisol amount was measured in E treatment with 188.74 ng/ml and the highest was found in control(P<0.05). There was a significant difference in blood glucose consentration of fishes in F treatment with (78.66 mg/dl) and control with 136 mg/dl as a highest one(P<0.05).

Comparison the nutritional value of cultured Penaeus vanname with marine shrimps Penaeus merguiensis and Penaeus semisulcatus

The purpose for which this study was intended wasto compare nutritive value among the farmed Vannamei, sea Green Tiger and Banana shrimps native to the PersianGulf. To provide the samples of farmed shrimps at the end of the farming season (Oct. 23rd through Nov. 22nd of 2011), we chosen one farm of the Holleh Shrimp Farming, from which 100 shrimps were randomly selected. From among these 100 shrimps, 3 to 5 ones were taken to conduct an analysis upon. Further, to obtain the Banana and Green Tiger shrimps sampling was done at the fishing season (July 23rd through Aug. 22rd of 2011) at Halileh Fishing Wharf located in Bushehr Fishing Harbor and also Bandar Abbas Wharf. The samples obtained were immediately kept in the ice powder. After some biometric tasks done upon them, they were at the shortest possible time transferred to a laboratory where they went through various experiments to determine their content of raw protein, fat, ash, moisture, various fatty acids and their types, cholesterol, vitamins A and E, and such mineral elements as iron and calcium. All the experimentswere carried out three times to establish confidence in the results to be obtained. Findings of the comparison showed the content of raw protein, fat, moisture, and ash of, respectively, 23.233%, 600%, 73.077% and 2.500% for the Vannamei samples, of 22.717%, 427%, 74.133% and 1.826% for our Banana shrimps and of 17.377%, 430%, 79.866% and 1.313% for the Green Tiger samples. A total of 24 fatty acids for the Vannamei shrimps and 27 for the Banana and Green Tiger were detected. SFA of the Banana shrimps was 368.45 mg/100g (51.76%), while those of the Vannamei and Green Tiger samples were observed, respectively, 363.54 mg/100g (37.26%) and 296.06 mg/100g (49.12%).A similar measurement for MUFA content of the three types of our samples revealed 243.85mg/100g (24.9%) for the Vannamei, 203.177 mg/100g (33.76%) for the Green Tiger and 179.033 mg/100g (25.14%) for the Banana shrimps. The content of PUFA unsaturated fatty acids in the Vannamei, 131 Green Tiger and Banana samples were, respectively, 370.660 mg/100g (37.84%), 101.573 mg/100g (16.9%) and 163.733 mg/100g (23.1%). Further, the comparison found a omega-3-fatty-acids total of 151.747 mg/100g(15.51%) for the Vannamei, 57.123 mg/100g (9.54%) for the Green Tiger and 130.460 mg/100g (18.46%) for the Banana species under study.