Essential Amino Acid Pattern Research Articles

Influence of γ-Radiation on the Nutritional and Functional Qualities of Lotus Seed Flour

In the present study, we investigated the physicochemical and functional properties of lotus seed flour exposed to low and high doses of gamma-radiation (0-30 kGy; the dose recommended for quarantine and hygienic purposes). The results indicated raw seed flour to be rich in nutrients with minimal quantities of antinutritional factors. Irradiation resulted in a dose-dependent increase in some of the proximal constituents. The raw and gamma-irradiated seeds meet the Food and Agricultural Organization-World Health Organization recommended pattern of essential amino acids. Some of the antinutritional factors (phytic acid, total phenolics, and tannins) were lowered with gamma-irradiation, while the seed flours were devoid of lectins, L-3,4-dihydroxyphenylalanine, and polonium-210. The functional properties of the seed flour were significantly improved with gamma-radiation. gamma-radiation selectively preserved or improved the desired nutritional and functional traits of lotus seeds, thus ensuring a safe production of appropriate nutraceutically valued products.

A simplified management of the in situ evaluation of feedstuffs in ruminants: Application to the study of the digestive availability of protein and amino acids corrected for the ruminal microbial contamination

The ruminal effective degradability (RED) and intestinal effective digestibility (IED) for dry matter, crude protein (CP) and amino acids (AA) were estimated by a simplified in situ method using pooled samples from rumen-incubated residues, which represented the ruminal outflow of undegraded feed. The effect of microbial contamination in the rumen was corrected using 15N infusion techniques. Studies were carried out for soybean meal (SBM), barley grain (BG) and lucerne hay (LH) in three wethers cannulated in the rumen and the duodenum. Uncorrected values of RED for CP obtained either by mathematical integration or our simplified method were similar in all feeds. Microbial N in the pooled samples of SBM, BG and LH were 2%, 11% and 24% of total N, respectively. However, intestinal incubation eliminated this microbial charge by 100%, 99% and 88%, respectively. With microbial corrections, RED showed an increase, and IED showed a decrease, except for SBM. With this correction, intestinal digested CP was reduced by 2% in SBM, 13% in BG and 34% in LH. Corrected IED of AA was relatively similar in SBM (97–99%). However, large variations were observed in BG (74–93%) and in LH (10–88%). Digestion in the rumen and intestine changed the essential AA pattern. Overall, our results support that AA digestion is affected by the characteristics of their radicals and their contents in plant cell wall proteins. The accurate estimation of feed metabolisable AA or protein requires effective measures that are corrected by ruminal microbial contamination. The proposed in situ method largely simplifies these tasks and allows a more complete and less expensive feed evaluation.

The Optimum Dietary Essential Amino Acid Pattern for Male Taiwan Country Chicks

The objective of this study was to estimate the optimum dietary essential amino acid pattern for male Taiwan country chicks. A series of experiments was conducted with chicks, 14 d of age, for 2 wks. A basal synthetic diet was established using a dose response test for all essential amino acids referring to the broiler requirements recommended by NRC (1994). Twelve chicks were sacrificed at the beginning to provide initial body nitrogen data, and every group of six birds received the basal diet or a diet with a deficiency in a single essential amino acid in twenty one treatments by intubation according to their daily metabolic body weight (MBW). Deposited body nitrogen was determined using comparative slaughtering. According to the daily intake from the limiting amino acid per unit of MBW and the body nitrogen accretion rates for every two deficient groups with the same limiting amino acid but at different levels, a corresponding straight line was computed for each essential amino acid to intersect with a horizontal line made by the body nitrogen accretion rate of the control group. The x coordinate of the intersection represented the daily requirement for growth plus maintenance based on MBW corresponding to the essential amino acid. The amino acid ratios can be considered as the optimum pattern of dietary essential amino acids. The results, expressed with respect to lysine = 100, were arginine 105, methionine 81, histidine 34, tryptophan 18, leucine 103, phenylalanine 135, isoleucine 69, threonine 65 and valine 79. This pattern could be utilized to compute the dietary requirements (g/kg feed) for all essential amino acids by multiplying by the requirement of a single essential amino acid cited from the literature.

Nitrogen retention in man in relation to the level and pattern of essential amino acids.

Nitrogen retention in man in relation to the level and pattern of essential amino acids.

Nutritional properties of potato protein concentrate compared with soybean meal as the main protein source in feed for the double-muscled Belgian Blue bull

The objective of this experiment was to compare the nutritional properties of potato protein concentrate, a by-product of the starch industry produced entirely in Europe, with that of soybean meal (SBM), for growing cattle. The experiment was conducted on double-muscled Belgian Blue bulls, fitted with rumen, duodenal and ileal cannulas, according to a 4 × 4 Latin square design. They were fed three different iso-N and iso-net energy diets formulated according to the Dutch feed evaluation system, differing in the nature of the main protein source, which was either SBM (‘SBM’ treatment), potato protein concentrate (PPC, ‘PPC’ treatment) or an iso-N mixture of these two protein sources (‘mixed’ treatment). A fourth treatment consisted of ‘PPC’ supplemented by 9.5% digestible proteins supplied by duodenal perfusion of sodium caseinate (CAS, ‘PPC + CAS’ treatment). No significant difference was observed in the ruminal fluid pH, whereas both ‘PPC’ and ‘PPC + CAS’ had the effect of reducing the ruminal ammonia nitrogen (N-NH3) concentration. No significant difference was observed in the apparent intestinal digestibility of the dry matter (DM), organic matter (OM) or N. Outflows of non-NH3-N, microbial proteins and dietary proteins from the rumen were similar for ‘PPC’, ‘SBM’ and ‘mixed’, and increased with CAS infusion by 20%, 17% and 27%, respectively. On the basis of in vivo observations, the degradability of SBM and PPC proteins was estimated at 0.60 and 0.43, respectively, corresponding to the values quoted in the literature. The supply of digestible essential amino acids (EAA) was significantly greater with ‘PPC + CAS’ and did not differ among ‘SBM’, ‘mixed’ and ‘PPC’. This illustrates the difficulty of altering the amino acid (AA) pattern of digestible protein by the nature of the protein of dietary origin when an animal is fed a high nutritional value diet. N retention was not affected by replacing SBM with PPC, but increased by 10% with CAS infusion. On the basis of the plasma AA pattern, the supply of digestible Met was probably limiting with ‘SBM’, ‘mixed’ and ‘PPC’. The CAS perfusion supplemented all AA, including Met, leading to increased N retention. This improvement was limited, however, and N utilisation remained unchanged between treatments. In conclusion, despite a more favourable EAA pattern, PPC offered no advantage compared with SBM for growing bulls when diets were formulated according to the Dutch feed evaluation system.

The effects of dietary protein:energy ratio and amino acid pattern on nitrogen utilization and excretion of rainbow trout Oncorhynchus mykiss (Walbaum)

This study was undertaken to investigate: (1) the effects of both deficiencies and excesses in essential amino acids (EAAs) from an estimated optimum dietary EAA pattern on nitrogen (N) utilization and excretion of rainbow trout Oncorhynchus mykiss, (2) the effects of dietary digestible protein (PD): digestible energy (ED) ratio (PD:ED) on N utilization and excretion of O. mykiss and (3) the potential interaction of these two factors. A 3 × 3 factorial experiment was conducted, with the two factors EAA pattern and PD:ED ratio. The three levels of EAA pattern were: (1) optimum EAA pattern, (2) 60% deficiencies in the three amino acids arginine, histidine and lysine, and (3) 60% excesses in the three amino acids arginine, histidine and leucine. The three levels of PD:ED ratio were 18, 21 and 24 g MJ−1. Amino acid deficiencies from an optimum amino acid pattern caused reductions in mean N retention of 29 to 37%, with the greatest reduction associated with the lowest PD:ED ratio, and similar substantial increases in total N and ammonia‐N excretion at all of the dietary PD:ED ratios investigated. Amino acid excesses, however, did not negatively affect N retention or excretion. Increasing PD:ED ratio was associated with decreasing N retention and increasing N excretion over the range of dietary protein and lipid levels tested. Results of this study showed that a diet with optimum dietary amino acid pattern and lowest PD:ED ratio produced the highest N retention (47% of ingested N) and the lowest total N and ammonia‐N excretion of O. mykiss.

Effects of exogenous enzymes (phytase, non-starch polysaccharide enzyme) in diets on growth, feed utilization, nitrogen and phosphorus excretion of Japanese seabass, Lateolabrax japonicus

A feeding experiment was conducted to investigate the effects of exogenous enzymes (phytase, non-starch polysaccharide enzymes: WX and VP, supplied by DSM) on growth performance and excretion of Japanese seabass (Lateolabrax japonicus) (initial mass 6.26+/-0.10 g). A basal diet was used as a control that contained a mixed protein source, and lysine, methionine and valine were supplemented to simulate the essential amino acid pattern of fish meal. Four other diets were supplemented with 200 mg phytase (500 IU), 400 mg VP, 800 mg WX, or a combination of 800 mg WX and 400 mg VP per kg diet, respectively. Each diet was assigned to triplicate groups of fish in floating sea cages, and each cage was stocked with 60 fish. The results showed specific growth rate (SGR) and feed efficiency ratio (FER) were not significantly improved by the phytase supplementation. However, supplementations with WX and VP significantly enhanced the SGR and FER (P<0.05). Phosphorus retention was significantly increased by the supplementation with phytase, whereas nitrogen retention was also enhanced by supplementations of non-starch polysaccharide enzymes (P<0.05). The excretion experiment showed that the soluble phosphorus and ammonia nitrogen in starved fish were constant, irrespective of dietary treatments. The total phosphorus effluent in fish fed the diet with phytase supplementation was significantly lower compared with the control group after feeding to satiation (P<0.05), but soluble phosphorus excretion was still independent of dietary treatments. The ammonia excretion in satiated fish significantly decreased with supplementations of non-starch polysaccharide enzymes.

Effect of the dietary essential amino acid pattern on growth, feed utilization and nitrogen metabolism of European sea bass ( Dicentrarchus labrax)

The aim of this study was to evaluate the influence of the dietary essential amino acid (EAA) pattern on growth performance, feed utilization and nitrogen metabolism of European sea bass. A diet containing only intact protein (fish meal and wheat meal) was used as a control (diet C). Three semi-purified diets were formulated to be isonitrogenous (8% DM) and isolipidic (15% DM) and to contain crystalline-AAs replacing approximately 60% of fish meal protein-bound nitrogen of the control diet. The AA pattern of these diets was adjusted to resemble the overall AA pattern of the fish meal protein (diet FM); the overall AA pattern of the whole-body protein of sea bass (diet WBC) or to meet the ideal protein AA pattern estimated for sea bass (diet REQ). Each experimental diet was fed to juvenile sea bass (7.3 g) in triplicate for 42 days. Weight gain and specific growth rate were highest in fish fed the control diet, followed by FM, WBC and REQ diets. Voluntary feed intake was highest in fish fed the REQ diet, and did not differ within the other groups. Feed efficiency and protein efficiency ratio were similar between fish fed the control and FM diets, while it was lower in the other groups. At the end of the growth trial, whole-body dry matter and protein content were not significantly affected by dietary treatment, while lipid and energy contents were significantly higher in fish fed the control diet than the other diets. Visceral and hepatosomatic indices were significantly lower in fish fed the REQ diet compared to the other groups. Nitrogen retention (g kg BW − 1 day − 1 and % N intake) of fish fed the control and FM diets was significantly higher than that of fish fed the REQ diet. Total non-fecal N excretion (% N intake) was significantly higher in fish fed the REQ diet than in the other groups, among which no significant differences were observed. Specific activity of glutamate dehydrogenase was significantly lower in fish fed the control diet than the REQ diet. Specific activity of alanine and aspartate aminotransferases and glucose-6-phosphate dehydrogenase were not significantly affected by the dietary treatments. Fatty acid synthetase activity was significantly lower in fish fed the REQ diet than in the other groups, among which no significant differences were observed. Results of this study indicate that the best overall growth and feed utilization of sea bass juveniles were obtained with a dietary AA pattern that resembled the overall AA pattern of fish meal. A diet with an AA profile adjusted to meet the ideal protein AA pattern estimated for sea bass significantly depressed growth.

Nutritional Composition and Assessment of Gracilaria lemaneiformis Bory

AbstractThe chemical composition, mineral elements, vitamins, free fatty acids and amino acid content of the edible red alga Gracilaria lemaneiformis Bory, grown in the sea near Nan'ao island, Guangdong Province, were analyzed in the present study. Gracilaria lemaneiformis Bory showed a total sugar content of 14.65%. The protein content was 21%, of which approximately 41% was determined to be essential amino acids (EAA). The major amino acid components were glutamic acid, leucine, arginine, and alanine. Of the EAA assayed, methionine and cysteine appeared to be the most limiting amino acids compared with the EAA pattern provided by Food and Agricultural Organization of the United Nations. The total lipids content was 0.87% and comprised a high composition of unsaturated fatty acids (61%), mainly as linoleic acid and oleic acid, and a little amount of polyunsaturated fatty acid; palmitic acid was the main component (39%) of saturated acids. Relatively high levels of vitamin C, iodine, phosphorus, and zinc were also present in G. lemaneiformis. The nutritional composition between G. lemaneiformis and Nostoc flagelliforme, a rare alga that is widely eaten in Chinese society, was compared. The results suggest that N. flagelliforme can be substituted for by G. lemaneiformis, not only because of their similar shape, but also because of their approximate nutritional composition. Gracilaria lemaneiformis may possibly serve as a potential healthy food in human diets in the future.(Managing editor: Ping He)

The Protein Digestibility-Corrected Amino Acid Score (PDCAAS)—A Concept for Describing Protein Quality in Foods and Food Ingredients: A Critical Review

Protein Digestibility-Corrected Amino Score (PDCAAS) is discussed. PDCAAS is now widely used as a routine assay for protein quality evaluation, replacing the more traditional biological methods [e.g., measurement of the Protein Efficiency Ratio (PER) in rats]. PDCAAS is based on comparison of the essential amino acid content of a test protein with that of a reference essential amino acid pattern and a correction for differences in protein digestibility as determined using a rat assay. Although PDCAAS is a rapid and useful method, it often shows discrepancies when compared to PER values. These discrepancies relate to the following issues: uncertainty about the validity of reference patterns, invalidity of correction for fecal (versus ileal) digestibility, truncation of PDCAAS values to 100%, failure to obtain full biological response after supplementation of the limiting essential amino acid, discrepancies between protein and amino acid digestibility, effects of processing on protein quality, and effects of the presence of antinutritional factors in the matrix containing the protein. Part of the discrepancy between PDCAAS and PER can be overcome by modifications of PDCAAS. This article describes some proposed modifications and puts forward the suggestion that the rat protein fecal digestibility assay be replaced by an in vitro ileal amino acid digestibility assay based on a computer-controlled gastrointestinal model.

Amino acid profiles of sufu, a Chinese fermented soybean food

Sufu is a Chinese soybean cheese-like product obtained by solid-state fungal fermentation and ripening of tofu. The resulting “pehtze” is salted, followed by maturation in brine. Total (TAA) and free amino acid (FAA) profiles were determined during consecutive stages of sufu manufacture, i.e., tofu, pehzte (fungal fermented tofu), salted pehtze and in white, red and grey sufu, ripening in dressing mixtures of different salt content (8%, 11%, and 14% w/w). TAA in tofu, pehtze and salted pehtze totalled 547, 551 and 351 mg/g dry matter, respectively. FAA increased from total 1.3 to 15.6 mg/g dm in pehtze after fermentation of tofu by Actinomucor elegans and to 11.9 mg/g dm in salted pehtze. During ripening up to 80 days, total FAA in red sufu increased from 28 to 88 mg/g (8% salt), 28–63 mg/g (11% salt) or 26–42 mg/g (14% salt). In white sufu the levels of FAA were generally higher and the effect of salt was less inhibitory. Levels of FAA in white sufu increased in 80 days from 33 to 104 mg/g (8% salt), 27–92 mg/g (11% salt) and 19–73 mg/g (14% salt). The pattern of essential amino acids compared favourably with those of eggs and cow's milk. While FAA increased during ripening of red and white sufu, the ratio of each amino acid remained essentially constant, and glutamic acid, leucine, aspartic acid, alanine, phenylalanine and lysine were found in large quantities. However, in grey sufu the ratio was different, with large proportions of leucine, alanine, isoleucine, valine and phenylalanine found after ripening.

Protein and Amino Acid Requirements and the Composition of Complementary Foods

In this paper, factorial models of the dietary requirements for protein, nitrogen and individual indispensable amino acids are developed from published information on the relationship between age and protein deposition and between protein (amino acid) intake and nitrogen balance. The results are used to develop recommendations on the protein-energy ratio and the amino acid pattern of the diet. As part of the development of the models, factors affecting dietary protein digestibility, bioavailability and efficiency of utilization are discussed. Over the age range of 6-24 mo the models predict a fall in the weight-specific protein and amino acid requirement that results almost entirely from the changes in the growth rate of the children. It is also concluded that the requirement for the maintenance of body protein equilibrium (so-called maintenance) changes little with age. This contrasts markedly with the relationship between age and energy requirements. The amino acid modeling implies that the optimum pattern of individual essential amino acids also changes only marginally across the age range considered in the report. The calculations of the dietary requirement for whole protein imply that achieving a minimum protein-energy ratio of 6.3% is desirable. The amount of protein needed from complementary foods for breast-fed children is discussed.

Recovery and utilization of useful by-products from egg processing wastewater by electrocoagulation

The efficacy of a laboratory electrocoagulation (EC) system for treating egg processing plant waste-water (WW) is reported. For simulated and industrial egg processing WW, chemical oxygen demand, turbidity, and total suspended solids (TSS) were reduced 92 to 97%, 97%, and 99%, respectively, after treatment with EC. The final TSS concentration and turbidity values were 30 mg/L and 5 formazin turbidity units (FTU), respectively, similar to that of potable water standards. The recovered by-product solids had a similar pattern of essential amino acids compared to that of liquid whole egg and were comparable to the Food Agriculture Organization's essential amino acid profile for an ideal protein. The relative protein digestibilities of the recovered solids and a commercial corn meal averaged 130 and 56%, respectively, compared to liquid whole egg (set at 100%). An economic analysis of EC indicated that this treatment is economically feasible in that a savings of approximately $425,000 per year is possible in addition to recovering the capital equipment costs after about 14 mo of operation. These findings demonstrate that EC can be successfully applied to treat egg processing plant WW, yielding a high quality water suitable for recycling and valuable by-products having a highly digestible protein and fat value.

The optimum dietary essential amino acid pattern for rainbow trout (Oncorhynchus mykiss), to maximize nitrogen retention and minimize nitrogen excretion

The optimum dietary essential amino acid (EAA) pattern for a given animal species is considered to be that EAA pattern which results in maximum nitrogen (N) retention for protein growth and minimum N excretion. In a series of two 8-week experiments, we investigated the optimum dietary EAA pattern for rainbow trout (Oncorhynchus mykiss). Experimental diets were fed to quadruplicate tanks of fish, using the equalized satiation feeding method. In the first experiment, we used the amino acid deletion method to arrive at an estimate of optimum dietary EAA pattern for rainbow trout. There were 11 dietary treatments: 1 diet with a control EAA pattern, and 10 other diets with 40% deletions of a single EAA from the control pattern. Based on N utilization data, an estimate of optimum dietary EAA pattern for rainbow trout was made. In the second experiment, we compared this dietary EAA pattern with three other estimates of optimum dietary EAA pattern for rainbow trout, based on 1) amino acid composition of rainbow trout whole-body protein, 2) EAA requirements for rainbow trout published by the National Research Council, and 3) EAA requirements for rainbow trout based on nonlinear regression analysis. Response variables included growth rate, feed efficiency ratio and N retention and excretion. The EAA pattern associated with EAA requirements as published by the National Research Council was found to result in the highest mean N retention and lowest mean N excretion, and so was considered the best estimate of optimum EAA pattern of those compared.

Protein digestibility using corrected amino acid score method (PDCAAS) of four types of mushrooms grown in Jordan.

This study was conducted to evaluate the protein quality of four types of edible mushrooms common in Jordan in terms of protein digestibility-corrected amino acid score (PDCAAS), which is a combination of the chemical score of the limiting amino acid multiplied by true digestibility of the protein. True protein digestibility values were low (61.4, 73.4, 52.6 and 80.5 for Terfezia claveryi, Pleurotus ostreatus, Tricholoma terrum and Agaricus macrosporus, respectively). Based on the essential amino acids pattern requirements for children, the limiting amino acids in P. ostreatus and A. macrosporus protein were sulphur-containing amino acids with chemical scores of 0.61 and 0.50, respectively. However, lysine was the limiting amino acid in the protein of T. claveryi and T. terreum with chemical scores of 0.71 and 0.67, respectively, and the PDCAAS was 0.43, 0.45, 0.35 and 0.40 for the mushrooms types, respectively. Considering the pattern of essential amino acid requirements of laboratory rats, the sulphur containing amino acids were the limiting amino acids in the protein of T. claveryi, P. ostreatus, T. terreum and A. macrosporus with chemical scores of 0.56, 0.30, 0.34 and 0.25, respectively. The PDCAAS were 0.34, 0.22. 0.17 and 0.20, respectively. It is concluded that the four mushroom types studied are of low protein quality.

Colostrum effects on the gastrointestinal tract, and on nutritional, endocrine and metabolic parameters in neonatal calves

Newborn calves are characterised by marked cardio-respiratory, metabolic and endocrine changes which continue during ensuing weeks and months. Thus, although the somatotrophic axis is basically functioning in neonatal calves, it is not yet mature. The speed of the adaptations of the various traits differs widely. The ability to digest colostrum and milk requires specific structures and functions of the gastrointestinal tract. Colostrum composition exhibits major changes after the onset of lactation. Colostrum intake is important for passive immunity, but also for the provision of carbohydrates, lipids, proteins, minerals and vitamins. In addition, colostrum contains hormones, growth factors, cytokines, enzymes, polyamines and nucleotides, which in the neonatal calf can exert biological effects. Thus, insulin-like growth factor I, which in colostrum is present in high amounts, may enhance gastrointestinal tract development and function of neonatal calves. Colostrum should be ingested as soon as possible after birth for efficient and sufficient absorption not only of immunoglobulins, but apparently also of (essential and non-essential) fatty acids and fat-soluble vitamins (β-carotene, retinol and α-tocopherol). The pattern of essential amino acids and the glutamine/glutamate ratio in blood plasma also greatly depend on whether and when colostrum is fed. In addition, there are considerable effects on hormones (especially on concentrations of insulin, glucagon, insulin-like growth factor-I, including its binding proteins, and cortisol) that are dependent on time and amount of colostrum fed.

The influence of dietary protein and fat levels on tissue free amino acid levels of fingerling rainbow trout ( Oncorhynchus mykiss)

The influence of six semi-purified diets having different nutrient composition on the tissue free amino acid (FAA) levels of fingerling rainbow trout was examined. Four balanced amino acid diets (casein:gelatin=6:1) with combinations of two protein levels (35% (LP) and 50% (HP)) and two fat levels (10% (LF) and 20% (HF)), and two imbalanced high-protein (50%) diets (IMB-HP, casein:gelatin=1:1) with two fat levels (LF and HF), were each fed to duplicate groups (30 fish/group, 10 g/fish) for 6 weeks at 15°C. FAA in plasma, liver, dorsal white muscle and brain at 12 h after the last feeding were compared. Percentage weight gain of the HPHF diet group was the highest, but was not different ( P>0.05) from the others except for the IMB-HPLF diet group ( P<0.05). Levels of individual amino acids in the whole body protein were not markedly different among the treatments. Most of the free essential amino acid (EAA) levels in the tissues of the HP diet fed fish were higher than in those of the LP diet group. The levels of free phenylalanine and tyrosine of the HF group tended to be higher, and those of taurine lower, than the LF group. Most of the free EAA levels of the IMB diet group were lower even than the LP group. Correlations in EAA patterns between a given diet and tissue were high in plasma, but very low in muscle and brain. These findings suggest that not only dietary protein level and amino acid profile, but also dietary fat level affects the levels of certain FAA of rainbow trout tissues.

Nutritional composition of edible seaweed Gracilaria changgi

Gracilaria changgi, an edible seaweed was analyzed to determine its proximate chemical composition, mineral elements, vitamin C, β-carotene, free fatty acid and amino acid contents. G. changgi showed vitamin A activity of 865 μg rectinol equivalents/100 g sample. It contained a higher composition of unsaturated fatty acids (74%), mainly the omega fatty acids and 26% of saturated fatty acids (mainly palmitic acid) and also relatively high levels of calcium and iron. Major amino acid components are glycine, arginine, alanine and glutamic acid. Among the essential amino acids assayed, lysine with a chemical score of 53% appeared to be the most limiting when compared with the essential amino acid pattern of egg protein. This study was conducted to create a nutritional data for G. changgi in order to popularize its consumption and utilization in Malaysia. Comparisons to corresponding nutrient values in several commonly consumed local vegetables were also made.

Optimizing Dietary Amino Acid Patterns at Various Levels of Crude Protein for Cats

EXPANDED ABSTRACT Experiments with rats (Heger 1990, Stucki and Harper 1962), chicks (Bedford and Summers 1985, Stucki and Harper 1961), turkeys (Bedford and Summers 1988) and pigs (Wang and Fuller 1989) have shown optimal growth rates when the dietary essential amino acid (EAA) 3 nitrogen to total nitrogen (E:T) ratios were between 0.4 and 0.65. It has been consistently found that diets containing only EAA (E:T 5 1.0) yield poor growth rates. Taylor et al. (1996) showed that in kittens fed diets that contain EAA as the sole source of nitrogen [E:T 5 1.0, with the EAA pattern proportionate to the NRC requirements (NRC 1986)], weight loss results. Plasma amino acid concentrations of methionine (and possibly arginine) suggested toxicities of these amino acids. Also, marked depressions in the concentrations of proline and asparagine suggested that these amino acids might be conditionally essential. A near-maximal growth rate for the group receiving all EAA (E:T 5 1.0) was achieved when methionine and arginine were limited to not more than 2.25 times the NRC requirements. No response was obtained with proline and/or asparagine supplementation to the all-EAA diet or when these two amino acids were removed from the control diet. Thus asparagine and proline are clearly dispensable under all conditions tested thus far. These results suggest that the poor growth rates recorded in other species given only EAA (E:T 5 1.0) diets are the result of an intolerance of one or more EAA, rather than a metabolic inability of animals to synthesize dispensable amino acids (DAA) at a rate fast enough for rapid growth, as previously suggested by Harper (1974). Here we report the results of weight gains of kittens fed a wide range of crude protein (CP) levels at various E:T ratios in which excesses of essential amino acids that depress weight gains were avoided. Materials and methods. A control purified diet (CD) was

Nutrient composition and food potential of Parkia roxburghii, a less known tree legume from northeast India

The nutrient compositions of Parkia roxburghii kernels and pods (i.e. tender, immature and mature) were determined. Protein content of the kernel was 29% and that of pods 13–19%. Similarly, fat content was highest (34%) in the kernel and ranged from 1–16% in the pods. Unsaturated acids Oleic, linoleic and linolenic acids made up 63–68% of the total fat in the pods as well as the kernels. The total essential amino acids amounted to 33%, 36% and 39% in the tender, immature, mature pods, respectively, and 42% in the kernels. The essential amino acid pattern of the kernel was comparable to the FAO/WHO/UNU (1985) amino acid requirement for preschoolers. However, the amino acid scores of the tender, immature and mature pods were 64, 84 and 92, respectively, with sulphur amino acids as the limiting amino acids in all the pod samples.