Nutritional and biological evaluation of tobacco leaf protein concentrate

A tobacco leaf protein concentrate (TLPC) from bidi tobacco leaves was prepared by a heat coagulation method which contained 52% protein and was free from nicotine and polyphenols. When TLPC was fed to weanling wistar albino rats to supplement 25% of the dietary protein, the growth of the animals was found to be comparable to control animals. Reproductive performance of male and female rats fed the TLPC supplemented diet was normal and no histopathological changes were seen in their tissues.     

The immunological consequences of a high intake of soya-bean protein in man

Fifty-three volunteers undertook to consume at least four meals per week based on soya-bean textured vegetable protein (TVP) for 42 days. Changes in dietary habits were assessed and there were no changes in the distribution of energy between fat, carbohydrate and protein. Plasma total and high-density lipoprotein cholesterol and plasma triglycerides were significantly increased during the experiment (P<0.001). There were no significant changes in soya-specific antibodies (immunoglobulins G, A or M) or in total serum immune complexes in the group as a whole. There was no relationship between the intakes of either milk protein or soya-bean protein and their corresponding antibodies, irrespective of immunoglobulin class. It is concluded that, for most human subjects, there are no apparent immunological consequences of consuming a high intake of soya-bean protein. However, the plasma of a minority of the volunteers showed a marked increase in soya antibodies of some or all classes.     

Nutritional quality of sunflower seed protein fraction extracted with isopropanol

This study investigated the nutritional effect of sunflower seed proteinfraction (SSPF) extracted with isopropanol on growth, plasma and tissuelipid profile, protein content and erythrocyte membrane lipid profile ofrats. Dehulled sunflower seeds were extracted with isopropanol at 50±1 ^°C resulting in a protein fraction (71.5%) with low residualchlorogenic acid (0.07%) and fiber (3.3%) contents. Rats fed thesunflower seed protein fraction had a similar body weight gain and foodefficiency ratios in comparison to those fed casein. Rats fed SSPF incontrast had a significantly higher growth and food efficiency ratio thanthe rats fed sunflower meal (SM), extracted with hexane. However,dietary proteins exerted a separate effect on plasma total cholesterol,low density lipoprotein (LDL)-cholesterol, low density lipoprotein to highdensity lipoprotein cholesterol (LDL-C/HDL-C) ratio and triglyceridecontent. Sunflower seed protein fraction resulted in a significantdecrease in plasma cholesterol (p < 0.05) and LDL-cholesterol (p <0.02) levels compared to the casein fed rats. Membrane phospholipidprofile also showed a marked variation with the type of dietary protein.Rats fed SSPF and SM did not show much variation in plasma lipids, plasmaproteins, liver and brain lipids and membrane phospholipid concentrations.Protein content, liver and brain lipid profile of the groups fed SSPF andcasein were comparable, suggesting that the nutritional value of SSPF isbetter than SM and equivalent to that of casein.     

Isolation and chemical composition of protein concentrates from soya-bean,rice-bran and protelan

Protein concentrates, were isolated from three by-products, defatted soya-bean, rice-bran and protelan. The conditions of maximum protein isolation differed according to the material used. Concentrates of 55.70%, 22.41% and 57.45% protein could be obtained from soya-bean, rice-bran and protelan; respectively. Hydrogen peroxide was found to increase the isolated nitrogen from protelan and rice-bran, however, in soya-bean it was without any positive effect. Essential amino acid contents were found corresponding to the amino acid of the FAO recommended amino acid composition except for methionine in all cases and lysine in protelan.     

Evaluation of biological quality of protein concentrates from different vegetable protein sources

The quality of protein concentrates coming from conventional and non-conventional vegetable sources was evaluated. The protein quality was assessed by the multi-point assay RPV. Whole body weight gain, weight gain corrected for the gastrointestinal content (G.I.), total body nitrogen and total liver nitrogen were used as response parameters. The various protein sources ranked differently depending upon the response parameters utilized, but a great majority of the sources had a good nutritional value (over 0.5). The gastrointestinal content is one of the principal factors responsible for the differences found. However, even after correcting for the G.I. content, some differences remained. For the various protein sources, the nitrogen deposition in the liver correlates satisfactorily with the whole body nitrogen deposition, if in the calculation of the regression line, the data for faba bean and tobacco were omitted (respectivelyr=0.610 andr=0.925). On the whole, these data indicate that most plant protein concentrates in suitable combinations and properly processed, may become a promising alternative to animal proteins.     

Limiting amino acids in raw and processed amaranth grain protein from biological tests

Amino acid supplementation studies with young rats were carried out using raw and processed amaranth grain (A. cruentus) of dark- and cream- or light-colored seeds. The results of various studies repeatedly indicated that threonine is the most limiting amino acid in raw and processed, dark and cream-colored grain. Protein quality as measured either as NPR or PER was improved by threonine addition alone or with other amino acids and decreased liver fat to values similar to those measured with casein. This finding contradicts the reports that state that leucine, determined by chemical score, is the most limiting amino acid. Leucine addition alone or with other amino acids did not improve protein quality. The study confirmed cream-colored grain to be nutritionally superior to dark grain and that properly processed grain, light- or dark-colored, has higher protein quality than raw grain.INCAP Publication I-1525     

Nutritional quality of the protein in quinoa (Chenopodium quinoa,Willd) seeds

The nutritional quality of protein in quinoa seeds has been determined by amino acid assay and by animal feeding experiments. The amino acid composition of the protein in raw quinoa and washed quinoa show similar pattern. The first limiting amino acids were the aromatic amino acids thyrosine + phenylalanine giving a chemical score of 86 for protein in raw quinoa and 85 for protein in washed quinoa. Threonine was the next limiting amino acid followed by lysine. The amount of lysine and sulfur amino acids (methionine + cystine) was relatively high. In general, the content of essential amino acids in quinoa is higher than in common cereals. The animal experiments showed NPU values of 75.7, BV of 82.6 and TD value of 91.7 for the protein in raw quinoa. Results of the in-vitro enzymatic methods showed that the digestibility of the protein in quinoa is comparable to that of other high quality food proteins. The corresponding experiments carried out with samples of guinoa seeds, which have been processed to remove the saponins, showed that, the saponins do not exert any negative effect on the nutritive quality of the protein.     

Nutritional quality of pearl millet flour and bread

Market samples of pearl millet flour and bread from Saudi Arabia were analysed for chemical composition and nutritional quality. Pearl millet flour contained, on a dry weight basis, 17.4% protein, 6.3% fat, 2.8% fiber and 2.2% ash. Lysine was the most limiting essential amino acid with a chemical score of 53 (FAO/WHO, 1973). Linoleic acid (44.8%), oleic acid (23.2%) and palmitic acid (22.3%) were the dominant fatty acids in millet oil followed by stearic acid (4.0%) and linolenic acid (2.9%). The invitro protein digestibility (IVPD) of millet flour was 75.6% and the calculated protein efficiency ratio (C-PER) was 1.38 in comparison to ANRC casein values of 90% and 2.50, respectively. Baking at 300°C for 15 min had only little effect on the proximate and fatty acid composition of the bread but decreased the arginine, cystine and lysine contents by 31.3%, 15.8% and 13.8%, respectively. The IVPD was not affected but the C-PER decreased by 18% on baking.     

Amino acid composition and biological evaluation of the protein quality of high lysine barley genotypes

The protein quality of high lysine barley genotypes Notch₁ Notch₂,Riso-1508 and Hiproly grown in Indian soil was evaluated by determining amino acid composition and also by rat growth and nitrogen balance studies. Protein and fat contents were found to be highest in Riso-1508. Lysine concentration (5.26 g/16g N) of Riso-1508 was also highest compared to the other high lysine genotypes. Rat feeding trials indicated that the growth promoting qualities of the proteins of genotype Riso-1508 were significantly (p < 0.05) higher than the low lysine barley genotype. The comparatively low lysine barley diet had more digestible protein than the high lysine barley diet. However, the BV and NPU of the high lysine barley were significantly (p < 0.05) higher. This improvement is of importance in meeting the essential amino acid requirements of man as well as other monogastric animals. The study showed that the high lysine barley harvested in Indian agroclimatic conditions retained high lysine quality.     

Nutritional quality of proteins in grain sorghum

Grain sorghum is low in protein content Lysine, threonine and tryptophan are the limiting amino acids in the proteins of grain Sorghum. Protein fractionation studies have shown that prolamine and glutelin are the principal protein fractions. Increase in protein content of grain Sorghum leads to an increase in prolamin fraction and decreases the nutritional quality. Environmental factors such as location, chemical fertilizers, plant population and chemical treatments influence the protein content and amino acid pattern. The presence of tannins in grain Sorghum reduces the digestibility and nutritional quality.

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Zusammenfassung Die Caryopsen von Sorghum-Hirse haben einen geringen Eiweißgehalt. Lysin, Threonin und Tryptophan sind die limitierenden Aminosäuren ihres Eiweißes. Untersuchungen über die Eiweiß-Frankrionierung haben ergeben, daß Prolamin und Glutelin die Haupt-Eiweißfranktionen sind. Erhöhung des Eiweißgehaltes von Sorghum-Korn führt zur Erhöhung der Prolamin-Fraktion und damit zum Abfall der Biologischen Eiweißwertigkeit. Umweltfaktoren, wie Standort, chemische Dünger, Pflanzendichte und chemische Pflanzen-Behandlung beeinflussen den Eiweißgehalt und die Art des Aminosäuremusters. Anwesenheit von Tanninen (Gerbstoffen), im Sorghum-Korn reduzieren seine Verdaulichkeit und die Biologische Eiweißwertigkeit.

     

Comparison of the structure-property relationships for PTT and PET fibers spun at various take-up speeds

A comparison of poly(trimethylene terephthalate)(PTT) and poly(ethlene terephthalate)(PET) fibers spun at various take-up speeds was presented. Fiber characterization included tensile and thermal properties, optical birefringence, density, sonic modulus, boil-off shrinkage, and wide-angle X-ray diffraction. The phenomenon of stress-induced crystallization was inferred from the X-ray diffraction diagrams for fibers spun with take-up speeds over 4000 m/min. The tenacity and elongation of PTT and PET fiber showed typical results, but the initial modulus of PTT fiber was nearly unchanged over the entire take-up speed range (2000–7000 m/min), whereas that of PET, as expected, increased monotonically with increasing take-up speed. This divergent behavior could be explained by the different molecular deformations in the c-axis as determined from X-ray diffraction patterns. The fiber crystallinity, density, and heat of fusion of both polymers increased with take-up speed. The boil-off shrinkage decreased with increasing take-up speed. The optical birefringence of the two fiber types showed a maximum level at a take-up speed of ca. 5000 m/min. The melting temperature behavior of PTT fiber was different from that of PET fibers. It was found that PTT is less sensitive to stress induced changes at high spinning speeds than is PET.     

Nutritional quality of some improved cultivars of cowpea

The seeds of 13 improved cowpea cultivars were analysed for proximate composition, methionine, tryptophan and polyphenols. Considerable genetic variations were observed for the contents of protein, nonprotein nitrogen, limiting amino acids and polyphenols. The globulins contributed about 50% of the total seed proteins. A significant proportion of proteins of high protein cultivars was found to be insoluble. The proteins of most of the cultivars were found deficient in methionine and tryptophan. Methionine and tryptophan levels were negatively correlated with protein and positively correlated with carbohydrate contents. The cultivars with colored seed coats contained higher amounts of polyphenols. The difference in polyphenol content between various cultivars were due to seed coat polyphenols.     

不同三叶草品种的农艺性状与营养特性比较

为了筛选出在湖南省低海拔地区适应性较强的三叶草品种加以推广应用，2003～2005年采用随机区组设计，对6个三叶草品种进行了农艺性状观察和营养成分测定。结果表明：在湖南省低海拔地区，加拿大普通型红三叶越夏能力强、抗病虫性强、鲜草产量高、蛋白质含量高；海发三叶草和海发白三叶表现较好，粗蛋白含量高；瑞文德白三叶营养价值高，但鲜草产量低。这4个三叶草品种均可在湖南低海拔地区种植，但以加拿大普通型红三叶最适宜推广。     

Nutritional quality of chickpea (Cicer arietinum L.): current status and future research needs

The nutritional composition and the affects of processing and storage and anti-nutrients on nutritional value of chickpeas are reviewed. Future research needs are discussed.Submitted as J.A. No. 431 by the International Crops Research Institute for the Semi-Arid Tropics (ICRASAT).     

不同产地紫米营养成分比较及其相关性分析

为评价不同品种紫米淀粉、脂肪、花青素、多酚、氨基酸和矿质元素间的差异,探究不同营养成分之间的关系,选取云南墨江（MJ）、湖南新化（HN）、贵州黎平（GZ）和陕西汉中（SX）4个产地的紫米,并与红米（R）、黑米（B）进行比较。结果显示,不同产地紫米成分含量存在差异,具有不同营养特征。HN紫米的淀粉含量最低（68.13%）,脂肪（2.38%）、矿质元素Fe、K、Mg、Mn、Na、P、Zn含量最高,其中Mn（80.37 mg/kg）、Na（10.75 mg/kg）元素显著高于其他产地;MJ和SX紫米花青素（533.03 mg/kg,412.54 mg/kg）、多酚（340.55 mg/100 g,387.91 mg/100 g）含量显著高于其他产地,而GZ紫米花青素（156.55 mg/kg）和多酚（239.23 mg/100 g）显著低于其他产地紫米。SX紫米氨基酸总量（74.37 g/kg）与必需氨基酸（total essential amino acids,ΣEAA,26.09 g/kg）含量最高,与其他紫米差异不显著。紫米成分间相关性分析显示,花青素与多酚呈极显著正相关（0.625）,二者分别与Ca呈显著负相关（-0.571,-0.549）。Asp、Gly与Fe、Ca呈显著正相关,大部分元素间呈显著正相关。不同有色稻米间,红米淀粉（74.73%）含量最高,花青素（9.05 mg/kg）、氨基酸总量（55.94 g/kg）、ΣEAA（19.78 g/kg）、Fe（6.51 mg/kg）、Mg（609.41 mg/kg）、P（1746.72 mg/kg）元素含量最低,与紫米和黑米差异显著（P<0.05）。黑米花青素（533.03 mg/kg）、多酚（453.53 mg/100 g）含量显著高于（P<0.05）其他有色稻;黑米和紫米氨基酸含量差异不显著（P>0.05）,但显著高于（P<0.05）红米。有色稻ΣEAA与非必需氨基酸总量（total non-essential amino acid,ΣNEA）比例在0.54左右。主成分分析将3种有色稻分为红米、紫黑米两组,前3个主成分可以解释总方差的91%。第一主成分（PC1）贡献率为67.5%,代表矿质元素,说明产地是有色稻米成分组成差异的主要原因。第二主成分（PC2）占总方差的18.2%,主要为总花青素含量、氨基酸等。     

海南与浙江产铁皮石斛主要营养成分分析比较

采用国标方法分别对海南产和浙江产铁皮石斛的主要营养成分（蛋白质及氨基酸、脂肪及脂肪酸、总多糖及矿质元素）的组成和含量进行测定。结果表明,海南产铁皮石斛中的粗脂肪、粗纤维、灰分、总多糖和水与浙江产铁皮石斛差异显著（p<0.05）,粗脂肪和粗蛋白含量与浙江产铁皮石斛则差异不显著（p>0.05）;两种铁皮石斛同时含有多种人体必需矿物质,其中以K、Mg、Ca和P的含量较高,尤其是K和Ca含量较高,不过,海南产铁皮石斛中微量元素的含量均要高于浙江产铁皮石斛。此外,两种铁皮石斛中不饱和脂肪酸含量均较高,但海南产铁皮石斛要比浙江产铁皮石斛更符合联合国粮农组织（FAO）提出的人类膳食中（ω-6）/（ω-3）的推荐值。两种铁皮石斛中必需氨基酸含量较高,两种铁皮石斛中的第一限制性氨基酸均为赖氨酸,且海南产铁皮石斛的必需氨基酸总量均要高于浙江产铁皮石斛。因此,海南产铁皮石斛具有较高的营养价值和良好的开发应用前景。     

Oil and protein quality of groundnut mutants

Variability in oil quality was observed in four groundnut mutants (TG-1, TG-3, TG-14, TG-16) induced by -irradiation. The fatty acid composition of the mutants differed from their parent Spanish Improved. All the mutants had lower linoleic and higher oleic acid than the parent Spanish Improved. TG-3 and TG-14 had substantially higher linoleic acid and lower oleic acid as compared with TG-1 and TG-16. Other fatty acids also showed minor variation amongst mutants and Spanish Improved. The ratio of oleic to linoleic acid, which is an index of oil stability, was 2.7 and 3.3 fold respectively in TG-16 and TG-1 as compared with Spanish Improved.Protein percent in TG-1, TG-14 and TG-16 was higher than in Spanish Improved. Amino acid analysis of protein from mutants indicated decreases in methionine and cystine and an increase in tryptophan as compared with Spanish Improved. Other amino acids did not show any major variation between the mutants and Spanish Improved. In all varieties except TG-16, lysine was the first limiting amino acid; threonine was second limiting in all mutants. The essential amino acid content per kernel was higher in mutants than in Spanish Improved.     

Nutritional quality of semi-arid grassland in western Spain over a 10-year period: changes in chemical composition of grasses, legumes and forbs

From 1987 to 1996, the nutritional quality of the main botanical components (grasses, legumes and forbs) in semi-arid grasslands in the dehesa ecosystem in western Spain was analysed. Herbage samples were collected at the end of spring, in 30 locations, at two different topographic positions (upper and lower slope zones). Herbage mass over 2 cm and proportion of botanical components were estimated and samples were analysed for crude protein, neutral-detergent fibre (NDF), hemicellulose, cellulose, lignin and in vitro dry matter digestibility (DMD). Analysis of variance revealed a significant effect of sampling year on the herbage mass, proportion of botanical components and their nutritional quality. The three botanical groups, grasses, legumes and forbs, followed similar year-to-year trends in their crude protein, cellulose and lignin contents and in vitro DMD. Herbage mass was not significantly related to any meteorological variables, suggesting that interannual variation in biomass production of botanically complex pastures cannot be explained by a single factor. However, annual precipitation was significantly related to the proportion of the botanical group that was dominant at each slope zone: grasses in the lower zone and forbs in the upper zone. In the upper zone, spring precipitation explained part of the interannual variation in the NDF, cellulose, lignin contents and in vitro DMD of the botanical components.     

Prediction of strength and weavability of blended spun yarns

In this paper, we report on predicting the strength of polyester/viscose spun yarns made on ring, rotor and air-jet spinning systems. A system has been developed to measure the weavability of yarns. Hamburger’s fibre bundle theory is modified to predict the strength of blended yarns from the strengths of single-fibre component yarns. The modified model predicts blended yarn strength more accurately than the original Hamburger’s model emphasizing the importance of yarn structure on blended yarn strength. The weavability of blended yarns is measured on a CTT instrument incorporating a shedding device which addresses the stresses viz., cycle extension, flex abrasion and beat up occur during weaving. The measured weavability compared well with that obtained on a commercial Sulzer Ruti Reutlingen Webtester. Yarn structure and strength and cohesion of fibres affect the strength and weavability of yarns.