Studies on α-amylase and trypsin inhibitors in legume seeds using agar diffusion and isoelectric focusing techniques

Amylolytic and tryptic inhibitors of faba bean extracts were determined by an agar diffusion test. The amylolytic inhibitor had protein characters. Furthermore, water-soluble trypsin inhibitors ofCicer arietinum, Lens esculenta, Lupinus termis, Phaseolus vulgaris, Pisum sativum, Trigonella foenum-graecum andVicia faba which were separated by polyacrylamide gel isoelectric focusing (PAGIF) in thin-layers, showed species specific patterns. Negative staining showed 10 bands for French beans, 9 for fenugreek seeds, 8 for lentils and chickpeas, 7 for peas and 6 for faba beans. Lupin seeds were free from trypsin inhibitors. Treatments (soaking, germination and heat processing) of faba beans reduced the number of trypsin inhibitors in PAGIF patterns, less after soaking and germination, but more after roasting and frying. No inhibitors were detected after cooking.     

Tannins,Trypsin Inhibitors and Lectin Cytotoxicity in Tepary (<Emphasis Type="Italic">Phaseolus acutifolius</Emphasis>) and Common (<Emphasis Type="Italic">Phaseolus vulgaris</Emphasis>) Beans

This study compared the levels of antinutritional components and cytotoxic effect of extracts, from tepary (Phaseolus acutifolius) and common (Phaseolus vulgaris) beans. Antinutritional factors were evaluated by determining their effect on the viability of epithelial cells isolated from rat small intestine. The protein and carbohydrates content were similar in all the genotypes studied (20 and 60%, respectively). Common beans presented higher content of trypsin inhibitors, tannins and lectins than tepary beans. There was not a significant correlation between tannins and cooking time. However, water absorption and cooking time correlated significantly (p < 0.05). Considerable variation was observed in lectin activity (1302–18161 Ul/mg) of extracts from different beans. Tannins, lectins, trypsin inhibitors and fat content differed between bean varieties whereas protein content was similar. The percent cellularity on rat epithelial cells was significantly different among protein extracts from different bean cultivars and ranged between 53.5% and 87.4% (p < 0.05). These results suggest that the incorporation of tepary beans in the diet would not alter the current nutritional contribution of common beans or introduce adverse toxic effects. The agronomic characteristics of tepary beans make them attractive for cultivation. However, the harder to cook phenomenon may be a limiting factor that needs further consideration.     

Studies on the influence of temperature,relative humidity and microenvironment on the natural fermentation of African oil bean seeds to ‘Ugba’

Studies on the enhancement of the traditional production of Ugba (a protein-rich fermented food) from African oil bean seeds were undertaken by fermenting the bean seeds at different temperatures, relative humidities (RH) and microenvironments. Fermentation was monitored by pH, texture, amino-nitrogen content and the viable cell count of the substrate. The 40 °C, 98% RH or the 130 m high density polyethylene (HDPE) treatment increased the fermentation microflora from ca. 106 CFU/g to ca. 108 CFU/g with high initial changes in pH (5.8–ca. 7.9) and texture (2.0 kg/cm2 to between 1.4 kg/cm2 and 0.9 kg/cm2) in 24 hours. Products with amino-nitrogen contents of between 12.00 mg N/100 g dry matter and 14.00 mg N/100 g dry matter were obtained in 3 days. The cell count of the 30 °C, 80% RH or 70 m treatment increased from 106 CFU/g to ca. 107 CFU/g and the pH increased from 5.8 to about 6.7 with a coincident decrease in the texture value from 2.0 kg/cm2 to about 1.7 kg/cm2 in 24 hours. Products with amino-nitrogen contents between 15.00 mg N/100 g dry matter and 19.2 mg N/100 g dry matter were obtained after 3 days. Changes in the fermentation indicators were not significant at p0.05 (pH and texture) and at p0.01 (amino-nitrogen) after 3 days for the 25 °C, 59.9% RH or 50 m low density polyethylene (LDPE) treatment. Products of fermentation at the combined optimal conditions (80% RH, 35 °C and 70 m HDPE) compared very well with the traditionally fermented products in terms of pH, texture and amino-nitrogen content.     

Quick-cooking beans (Phaseolus vulgaris L.): II. Phytates,oligosaccharides, and antienzymes

Effects of the quick-cooking processes on phytate and oligosaccharide levels, and on trypsin and chymotrypsin inhibitors, were investigated in three bean varieties (Phaseolus vulgaris L.: Great Northern, red kidney, and pinto). Beans soaked in distilled water had lower levels of phytate-P than those soaked in a mixed salt solution. Leaching losses of oligosaccharides were nearly the same in different soaking treatments for all the beans except kidney beans. Residual trypsin inhibitor activities (TIA) in cooked quick-cooking beans were about 10% compared with about 20% for chymotrypsin inhibitor activities (CTIA) in the same bean products. -Irradiation was more effective in reducing TIA than CTIA and paralleled destruction by moist heat.Utah Agricultural Experiment Station Journal article no. 2480.     

Comparative study of the chemical composition of wild and cultivated beans (Phaseolus vulgaris)

Five wildPhaseolus vulgaris beans were compared with five cultivatedPhaseolus vulgaris beans in proximate composition, total (true) protein, amino acid composition, and toxic and antinutritional factors. The wild beans contained more protein (25.5% vs. 21.7%), ash (5.15 vs. 4.15%), crude fiber (7.08% vs. 5.04%) compared to cultivated beans while the former contained less fat (0.56 vs. 0.89%) and carbohydrates (61.64 vs. 68.05%). Sulfur amino acids were found to be limiting in both groups of bean as expected; however, the cultivated beans had a higher content of the limiting amino acids. Therefore, the cultivated beans showed a better amino acid profile than the wild beans. Toxic factors were not found in either type of bean; the determinations included saponins, alkaloids, and cyanogenic glycosides. The antinutritional factors investigated were hemagglutinins (lectins) and trypsin inhibitors. The wild beans presented a higher content of trypsin inhibitors (28 TUI per mg) and lectins (9.6) than the cultivated beans did (21 TUI per mg and 7 respectively). From the chemical point of view, domestication seems to be positive; however, the better protein nutritive quality of the cultivated beans should be further confirmed by biological assays.     

Food potentials of some unconventional oilseeds grown in Nigeria — A brief review

A brief review of literature on kernels ofCitrullus andCucumeropsis (egusi melon) species,Telfairia occidentalis (fluted pumpkin),Lagenaria (gourd) species all of Cucurbitaceae family and other oilseeds such asPentaclethra macrophylla (African oil bean),Parkia spp. (African locust bean) both of Mimosaceae family andButyrospermum paradoxum (shea butter) of Sapotaceae family which are grown and widely used as food in Nigeria is presented. The kernels of species of Cucurbitaceae form the bulk of unconventional oilseeds used for food in Nigeria. The nutritional value of some of the kernels and the physicochemical properties and storage stability of the oils obtained from them are discussed. The various consumable forms in which they exist are also described. The problems and prospects of these neglected oilseeds in Nigeria are highlighted.     

Growth and lipid metabolism as affected by feeding of hull-less barleys with and without supplemental β-glucanase

Three hull-less barleys, Washonupana (WSNP), Waxbar (WXB), and Bangsa (BGS), were fed to broiler chicks in 21% protein diets containing 0.5% cholesterol in replicate trials. A corn-based diet, with added cholesterol, served as a control. Alternate diets were supplemented with -glucanase (ENZ). -glucan content ranged from 4.9% to 6.1% and soluble dietary fiber (SDF) from 3.6% to 7.5% in the barleys. Data from the two trials were pooled for statistical analysis by the SAS General Linear Models procedure. In body weight gain, chicks fed WSNP — ENZ were lower (P<0.05) than all other treatments. The -glucanase supplement to the WXB and BGS barley tended to improve gains, but the differences were not significant for either barley. Feed to gain ratios were lowest (P<0.0001) for corn fed chicks and lower (P<0.05 toP<0.0001) for those fed the barley+ENZ diets compared to barley –ENZ. Chicks fed barley diets had lower (P<0.05) total serum cholesterol (TSC) and LDL-cholesterol than those fed corn diets, regardless of ENZ supplementation. For chicks on barley –ENZ diets, TSC levels for WSNP, WXB, and BGS were 146, 152, and 142 mg/dl respectively and for chicks on barley +ENZ diets, 218, 200, and 178 mg/dl. LDL-cholesterol levels followed the same trend and there was little difference in serum triglycerides. The BGS+ENZ lowered TSC 30% from the corn control compared to 10.7% and 18% for WSNP+ENZ and WXB+ENZ, suggesting additional hypocholesterolemic factors, possibly tocotrienol and SDF other than 13, 14 -D-glucans.Contribution No. J-2487, Montana Agricultural Experiment Station. This research was supported, in part, by a grant from the Montana Wheat and Barley Committee, Great Falls, MT, U.S.A.     

Effect of imazamox plus bentazon on dry bean (Phaseolus vulgaris L.)

Imazamox plus bentazon has the potential to provide broad spectrum weed control in dry bean (Phaseolus vulgaris L.). Field trials were conducted in Ontario over a two year period (2003 and 2006) to evaluate the effect of imazamox plus bentazon applied post-emergence at 25 + 600 and 50 + 1200 g ai ha⁻¹ on black, brown, cranberry, kidney, otebo, pinto, white and yellow eye beans. Treatments included a non-treated check. All treatments were maintained weed free during the growing season. The eight market classes responded similarly to imazamox plus bentazon. Imazamox plus bentazon applied post-emergence caused less than 4% visible injury at 7, 14 and 28 days after treatment. Imazamox plus bentazon applied post-emergence did not have any effect on plant height, shoot dry weight, seed moisture content and yield of dry bean. Based on these results, imazamox plus bentazon at the proposed maximum use dose can be safely used for weed management in black, brown, cranberry, kidney, otebo, pinto, white and yellow eye bean production in Ontario. Additional research is needed to determine if cultivars within a market class of dry bean differ in their response to imazamox plus bentazon.     

Effect of traditional open sun-drying and solar cabinet drying on carotene content and vitamin A activity of green leafy vegetables

Dried green leafy vegetables constitute a major dietary source of provitamin A carotenoids for people living in semi-arid areas of Tanzania. In the present study, eight vegetable varieties commonly consumed in these areas were either traditionally sun-dried or solar-dried, and the amount of provitamin A carotenoids were determined by HPLC. In the fresh blanched leaves, the contents of -carotene, -carotene, 9-cis--carotene and 13-cis--carotene were in the range of 526–917, 12–39, 80–136 and 16–40 g/g dry matter/basis; dmb, respectively. The average amounts of all-trans--carotene in the leaves after blanching, solar drying and open sun-drying were 662, 502 and 353 g/g dmb, respectively, all significantly different from each other (p <0.001). The average amounts of all-trans--carotene were 21, 15 and 8 g/g dmb (p <0.05) and of 9-cis--carotene 101, 82 and 63 g/g dmb (p <0.05) in the blanched, solar-dried and open sun-dried samples, respectively. Estimation of the amount of retinol equivalents provided by the dried vegetables for preparation of an edible portion of 100 g relish showed that solar-dried vegetables contributed more (between 120–275%) than the recommended level of vitamin A, and on average 43% more retinol equivalents than relishes of open sun-dried vegetables.Thus, it is concluded that the amount of provitamin A-carotenes in traditionally treated vegetables were highly reduced by open sun-drying while solar drying resulted in significantly more retention of the carotenes. All-trans--carotene and 9-cis--carotene were similarly affected as all-trans--carotene by the two drying methods. Consumption of a 100 g portion of solar-dried vegetable relish could provide the recommended daily intake of vitamin A.     

全周期胶园间作对豆薯和大豆的产量、品质和土壤速效养分的影响

研究在全周期胶园宽行间作豆薯和大豆的产量、品质和土壤速效养分的影响。结果表明,与单作相比,间作大豆产量显著降低40%(p0.05),间作豆薯产量略低但差异不显著(p0.05)。总体上,单作和间作处理豆薯和大豆不同位置的可溶性糖、淀粉、粗蛋白和粗脂肪的含量没有显著差异(p0.05),但间作提高了间作带中间区域豆薯的粗脂肪含量。单作豆薯和大豆平均土壤铵态氮、硝态氮均显著高于间作处理的不同位置(p0.05);单作豆薯和大豆土壤速效钾含量高于间作处理且显著高于单作小区两侧(p0.05);而单作豆薯和大豆土壤速效磷则低于间作处理,其中单作豆薯显著低于间作豆薯小区中间区域(p0.05)。综上所述,豆薯比大豆更适合间作于全周期胶园,间作对作物的品质总体上没有影响,但对降低土壤无机氮含量较明显。     

Relationship between content and intake of bean polyphenolics and protein digestibility in humans

The purpose of this study was to determine the effect of bean polyphenolics on bean protein digestibility in humans. Steam pressure cooking decreased tannic acid in beans by: 38.2 (white), 23.9 (red), 38.5 (white:black mixture, 50:50), 20.5 (Ipala black) and 44.4% (Jalpatagua black). The reduction in catechin was: 57.5, 97.6, 83.0, 78.7 and 88.4%, respectively. The content of tannic acid in dried cooked beans was: 284.9 in white, 834.5 in red, 620.2 in the white:black mixture, 1,021 in Ipala black and 1,009 mg/100 g in the Jalpatagua black bean. These percentages correlate significantly with fecal nitrogen (r=0.29, p<0.05). Catechin of the dried cooked beans was 7.5 in white, 27.4 in red, 25.4 in the white:black mixture (50:50), and 60.1 and 55.5 mg/100 g in each of the black cultivars, and correlated significantly with fecal nitrogen (r=0.34, p<0.01), absorbed nitrogen (r=–0.37, p<0.01) and protein digestibility (r=–0.35, p<0.01). It was concluded that one of the factors that reduces bean protein digestibility is the polyphenlic compound.     

Quick-cooking beans (Phaseolus vulgaris L.): I. Investigations on quality

Soaking three beans cultivars (Phaseolus vulgaris L.: Great Northern, kidney, and pinto) in mixed salt solution (sodium chloride 2.5% + sodium bicarbonate 1.5% + sodium tripolyphosphate 1.0% + sodium carbonate 0.5%) resulted in 80%–85% reduction in cooking time over corresponding controls. Irradiation (-rays) at 500 krads of soaked and dehydrated beans caused a reduction of nearly 50% in cooking time. Water uptake and leaching losses for each treatment during soaking at 22°, 37°, and 45°C were investigated. High temperature (37° and 45°C) and pH (9.0) caused greater water imbibition and total solid loss than at room temperature (22°C). Organoleptic evaluation revealed that quick-cooking Great Northern beans appear to be more acceptable than kidney and pinto beans. Quick-cooking cooked beans had better in vitro protein digestibility than conventionally cooked beans. Phenolic content was found to be inversely related to in vitro digestibility.Utah Agricultural Experiment Station Journal article no. 2481.     

不同加工阶段香草兰豆荚的广泛靶向代谢组学研究

采用基于LC-MS/MS的代谢组学方法,对加工过程中的香草兰豆荚中代谢物的动态变化进行研究。通过聚类分析、样本相关性分析和正交偏最小二乘判别分析表明鲜豆荚（FVB）与杀青豆荚（BVB）,发汗豆荚（SVB）与干燥豆荚（DVB）的组间差异比较小,其余各组的组间差异比较大。差异倍数分析表明,和FVB相比,其他豆荚上调的代谢物主要是黄酮类物质,并且以糖苷类物质为主。而下调的代谢物以核苷酸及其衍生物为主。火山图显示SVB与CVB差异显著的代谢物是最多的,有256种。FVB与SVB的上调差异显著的代谢物是最多的,有102种。只有FVB与BVB的上调差异显著代谢物的数量高于下调差异显著代谢物。当和FVB相比时,各阶段差异显著代谢物变化如下：上调的黄酮类化合物在BVB、SVB、DVB、CVB均包含黄酮、黄酮醇、黄酮碳糖苷、黄烷酮,而下调的还包含黄酮-木脂素;上调的脂质及其衍生物在SVB、DVB、CVB中包含脂质-甘油磷脂、脂质-甘油酯、脂质-脂肪酸,而BVB只包含脂质-甘油磷脂;上调的氨基酸及其衍生物在SVB中最高,达到12种,DVB、CVB阶段呈下降趋势,分别为7种和3种,下调的氨基酸及其衍生物随着加工的进行逐渐增多,陈化阶段多达16种。     

Bioavailability of tryptophan in selected foods by rat growth assay

Tryptophan bioavailabilities were estimated in 16 protein sources using 10 day rat growth assays with casein as the reference protein. Growth responses of rats fed test food diets were compared to growth responses of rats fed basal diets with graded levels of tryptophan ranging from 50 to 100 mg of tryptophan/100 g diet. Estimates of tryptophan availabilities were 85–100% for all products except whole wheat cereal (73%) and pinto beans (59%). Results of a previous study on lysine availability indicated that poor response to pinto beans was due either to poor digestibility or to the presence of some unidentified growth inhibitor.     

Digestibility of protein and amino acids in selected foods as determined by a rat balance method

Values (%) for true digestibility of crude protein and individual amino acids in 20 selected foods were determined by the rat balance (fecal) method. The products were fed as the sole source of protein in diets containing 8% crude protein (N × 6.25). Lowest true protein digestibility values (79–84) were obtained for pinto beans, kidney beans and lentils; intermediate values (89–92) were obtained for chick peas, beef stew, skim milk (over heated), rolled oats, whole wheat cereal, and pea protein concentrate; and highest values (94–100) were obtained for sausage, macaroni-cheese, rice-wheat gluten cereal, skim milk, tuna, soy isolate, peanut butter, chicken frankfurters, beef salami, casein and casein + methionine. In animal foods, peanut butter and soy isolate, the differences between true digestibility of crude protein and most individual amino acids were less than 5%. However, the values for true digestibility of methionine and cystine were up to 44% lower than those of crude protein in pinto beans, kidney beans, lentils, chick peas and pea concentrate. In these legumes, digestibility of crude protein was not a good predictor of digestibility of the limiting amino acids.     

Utilization of β-carotene fromSpirulina platensis by rats

The availability of -carotene from Spirulina as compared to standard all trans -carotene was studied by the liver and kidney vitamin A storage method. After 21 days of vitamin A depletion, the rats were repleted with -carotene from Spirulina and a standard source at two dietary levels (60 and 120 µg/day) for a 10 day period. At lower levels, the liver storage levels of vitamin A and the percent of -carotene absorption were comparable to those of the standard. At higher levels both these parameters of the Spirulina fed group were significantly (P<0.01) inferior to the standard source fed group. However, the Spirulina fed group showed better (P<0.05) growth than the standard fed group did at both low and high levels of feeding.     

Changes in carbohydrate and nitrogenous components and amylase activities during germination of grain amaranth

Grain amaranth (Amaranthus hypochondriacus), Yercaud local variety, was soaked overnight and germinated for 192 h taking the soaked grains as the zero time (0 h) sample. The changes in the activities of - and -amylases, starch, sugar, protein and lysine contents during germination are reported. Activity of -amylase was high in the 0 h soaked grains, while -amylase activity was high in 72 h germinated grains. The joint action of the amylases resulted in a decrease of starch content from 0 to 192 h in germinated grains and an increase in total sugars during the initial period of germination.Protein nitrogen was found to decrease from 48 h to 192 h accompanied by an increase in free amino acid and non-protein nitrogen contents. Total lysine content was found to be increased by 31% in 24 h germinated grain amaranth. Protein fractionation of raw, soaked and 24 h germinated grain amaranth showed that the distribution of different types of proteins varied during germination of the grains. An increase of water soluble protein content was noticed in 24 h germinated grains.     

Amaranth as a rich dietary source of β-sitosterol and other phytosterols

The analysis of 4 commonly available amaranth varieties (Amaranthus K343, RRC1011, K433, K432) revealed the presence of all three major phytosterols (beta-sitosterol, campesterol, stigmas-terol) with a total sterol content being several fold higher than those found in other studied plants. Substantial differences in total phytosterol content and beta-sitosterol content were found between the amaranth varieties. The most commonly cultivated amaranth variety in the United States, i.e., Amaranthus K343 was found to possess the highest levels of phytosterols of the varieties tested. The possibility of screening for superior amaranth varieties with various health properties is outlined.     

Quality attributes of three new improved lines of Nigerian lima beans (Phaseolus lunatus L. Walp.)

Three promising new improved lines of lima beans (Tpl 1^B, Tpl 7^A and Tpl 175^A) were evaluated for physicochemical properties and cooking quality. The beans varied in seed dimensions and weights with Tpl 1^B and Tpl 7^A having smaller seed volume than Tpl 175^A. Seed coat percentages, leached solids and swelling capacities were within a range of 10.2–19.6% (w/w), 0.44–0.92 g/100 g and 94.0–121.0 g/100 g dry bean, respectively. Cooking times varied between 62 and 81 min without soaking and were reduced by about 34%following a presoaking treatment in water for 12 h at room temperature (28 ± 1 °C). Small seeds absorbed higher amounts of water during soaking and required more cooking time than larger seeds. No significant (p>0.05) difference in cooked texture was found between unsoaked beans cooked for 50 min and soaked beans cooked for 30 min,suggesting that cooking times and cooked texture for all lines were improved through soaking.     

Effect of microwave radiation on dry bean seed infected with Xanthomonas axonopodis pv. phaseoli with and without the use of chemical seed treatment

Common bacterial blight (Xanthomonas axonopodis pv. phaseoli) is a seed-borne disease that is difficult to control in dry bean (Phaseolus vulgaris L.). Laboratory and field studies were conducted over a two-year period to determine the effect of microwave radiation on navy (cv. Navigator and Envoy) and pinto (cv. AC Ole) bean. Laboratory tests resulted in a 12 to 25% decrease in germination following 50–60 s of radiation, while less than a 10% loss was observed between 0 and 40 s. Pathogen viability was also tested, however the incidence of pathogen infection was low and no correlation was observed between exposure time and the incidence of colonization. In field studies conducted at Morden, MB (2012) and Ridgetown and Exeter, ON (2012–2013) microwave radiation and two chemical seed treatments (copper hydroxide 53.8% and pyraclostrobin + fluxapyroxad + metalaxyl) were evaluated for their effect on emergence, disease infection, seed pick, yield and return on investment. The application of microwave treatment decreased emergence by up to 7%, but did not impact the other parameters measured. Chemical treatment alone or in combination with microwave treatment also did not affect emergence, disease incidence, yield, seed pick, or return on investment.