Assessment of indigenous Nepalese soybean as a potential germplasm resource for improvement of protein in North American cultivars

Soybeans contain approximately 40% protein and 20% oil and represents an important source of protein in animal rations and human diets. Attempts are being made to increase further the overall protein content of soybeans by utilization of exotic germplasms. In this study, soybean cultivars from Nepal have been characterized and their potential as a germplasm resource for improvement of the protein content and quality of North American cultivars assessed. Soybean cultivars 'Sathia', 'Seti', 'Kavre', and 'Soida Chiny', indigenous to various regions of Nepal, contained 42-45% protein, which is significantly higher in comparison to that of the North American cultivar 'Williams 82' (39%). Fractionation of seed protein by high-resolution two-dimensional gel electrophoresis revealed differences in the protein profiles of these cultivars. Various isoelectric forms of glycinin and beta-conglycinin were identified by comparing the matrix-assisted laser desorption ionization time-of-flight mass fingerprinting data against the National Center for Biotechnology Information nonredundant database. Nepalese cultivar Sathia was distinct, lacking some isoelectric forms of acidic and basic glycinin subunits while expressing other unique forms. The contribution of these unique protein spots present in either Sathia or Williams 82 to the total protein content was quantified using scanning laser densitometry. Distinct restriction fragment length polymorphisms (RFLP) for group 1 glycinin genes were observed among the tested Nepalese genotypes, indicating sequence variation among the cultivars. Conversely, evaluation of RFLP for the genes encoding group 2 glycinins, beta-conglycinin, and Bowman-Birk proteinase inhibitors indicated a high degree of conservation in these genes. Determination of amino acid composition, a reflection of protein quality, indicated that the arginine content of the Nepalese soybeans ranged from 7.7 to 8.1%, which was 5-10% higher than the 7.4% expressed in Williams 82. Additionally, Karve and Seti contained significantly more cysteine than Williams 82. Nepalese high-protein soybeans having a desirable amino acid composition hold potential to increase the protein quality and diversity of North American cultivars.     

Characterization of allergens isolated from the freshwater fish blunt snout bream (Megalobrama amblycephala)

Fish are an important source of dietary protein for humans throughout the world. However, they are recognized as one of the most common food allergens and pose a serious health problem in countries where fish consumption is high. Many marine fish allergens have been extensively studied, but relatively little is known about freshwater fish allergens. This study identified two main allergens from blunt snout bream (Megalobrama amblycephala), a freshwater fish widely consumed in China. Sera from 11 patients with convincing clinical history of blunt snout bream allergy were utilized in IgE immunoblot analysis to identify prominent allergens. Several blunt snout bream proteins revealed specific binding to serum IgE, with the 47 and 41 kDa proteins being the most immunodominant among them. Two-dimensional gel electrophoresis (2D SDS-PAGE) enabled resolution of the 47 and 41 kDa proteins into several protein spots with distinct isoelectric points. 2D SDS-PAGE along with IgE immunoblot analysis further confirmed the strong reactivity of these protein spots with the pooled sera from blunt snout bream-sensitive patients. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis of the peptides generated by trypsin digestion of the different spots corresponding to the 47 and 41 kDa proteins indicated that these spots were isoforms of enolase and muscle creatine kinase, respectively. The potential allergenicity of these proteins was further verified by an bioinformatics approach using the full-length and 80 amino acid sliding window FASTA searches, which revealed a significant amino acid sequence homology between blunt snout bream allergens and several known inhaled and crustacean allergens.     

Dough Strain Hardening Properties as Indicators of Baking Performance

Bread loaf volume is an important economic criterion. Breeders, millers, and bakers need measurements allowing them to evaluate dough performance during processing. Strain hardening is an important dough property. It describes the stability of the gas cell walls and the ability of cells to expand further; therefore, the higher the strain hardening index (n), the better the baking performance. Dough exhibits strain hardening during uniaxial extensibility tests. However, obtaining n from an extensibility test is time consuming. The objectives of this study were to identify the extensibility parameters that contribute to n. Three parameters were retained in the model (R² = 0.90): dough strength (R_max), extensional delay (E_Diff), and initial slope of the curve (E_i). R_max was the largest contributor and was proportional to the dough strain hardening properties. E_Diff and E_i had a detrimental effect on n. The appropriateness of the model was validated with two sample sets (19 genotypes, 12 environments). Significant correlations were found between loaf volume and n (r = 0.52–0.64) for 7 of the 12 environments. The strain hardening index was found to be a good predictor for baking performance as judged by loaf volume.     

Comparative assessment of growth performance of three different indigenous goat breeds exposed to summer heat stress

A study was conducted to assess comparatively the growth performance of three different indigenous goat breeds during exposure to summer heat stress. The primary objective of the study was to observe the heat stress impact on the growth performance based on the body weight changes, allometric measurements, growth hormone (GH) concentration and peripheral blood mononuclear cell (PBMC) Insulin‐like growth factor‐1 (IGF‐1) mRNA expression pattern during the summer season in comparison with the local breed (Osmanabadi). Thirty‐six ten‐month‐ to one‐year‐old female goats of Osmanabadi, Malabari and Salem Black breeds were randomly divided into six groups, OC (n = 6; Osmanabadi control), OHS (n = 6; Osmanabadi heat stress), MC (n = 6; Malabari control), MHS (n = 6; Malabari heat stress), SBC (n = 6; Salem Black control) and SBHS (n = 6; Salem Black heat stress). Body weight was recorded at weekly intervals, whereas other growth and allometric measurements and blood collection were carried out at fortnightly intervals. Breed factor significantly (p < .05) influenced only few growth variables such as body weight, body mass index (BMI) and body condition score (BCS). However, heat stress treatment significantly (p < .05) reduced all growth parameters expect BMI. Further, the heat stress significantly (p < .01) increased plasma GH concentration in goats with significantly higher (p < .05) concentration recorded in OHS. Among the stress groups, the lower (p < .05) PBMC IGF‐1 mRNA expression was recorded in OHS, while the higher (p < .05) expression was observed in SBHS indicating the extreme adaptive capability of Salem Black breed. Thus, the results indicated that the Salem Black breed performed much better compared to both Osmanabadi and Malabari breeds indicating the superior ability of this breed to adapt to heat stress challenges. The results also indicated that plasma GH and IGF‐1 gene may act as ideal biomarkers for assessing the heat stress impact on growth performance in indigenous goats.     

Inhibitory effect(s) of polymeric black tea polyphenol fractions on the formation of [(3)H]-B(a)P-derived DNA adducts

Five polymeric black tea polyphenol fractions (PBP-1-5) were isolated from a popular brand of black tea. The effect of these PBPs and epigallocatechin gallate (EGCG), a major green tea polyphenol, was studied on the formation of [(3)H]-B(a)P-derived DNA adducts in vitro, employing rat liver microsomes. PBP-1-3 inhibited microsome-catalyzed [(3)H]-B(a)P-derived DNA adduct formation in vitro in a dose-dependent manner. This inhibition was further enhanced on preincubation of microsomes with each of the PBPs. PBP-4 was not effective per se and required preincubation with microsomes to exhibit its inhibitory effect, whereas PBP-5 remained ineffective with or without preincubation with microsomes. Further investigations revealed that the observed decrease in [(3)H]-B(a)P-DNA adduct formation was due to inhibition of isozymes of CYP450s by PBPs. Overall, results suggest that polymeric black tea polyphenol fractions retain one of the chemopreventive effects exhibited by the monomeric green tea polyphenol EGCG in vitro.     

Identification of parameters in transient water quality models from stochastic data

An approach is presented for the identification of parameters in time-varying water quality models from stochastic data measured at two points along a stream (input-output type data). The models are plug flow models described by linear-first order partial differential equations. The method employed is to reduce the partial differential equations to a set of ordinary differential equations with the method of characteristics from which an analytical solution is obtained. The time-lag phenomenon presented in plug flow models is used to correlate the input-output data. A gradient method (Bard's method) is employed to identify the parameters in the correlation equation.     

Chlorophyll Content, Hill Reaction and PEPcase Activity in Relation to Hybrid Vigour in Pearl Millet during Early Seedling Growth

Three hybrids of Pennisetum americanum L. Leeke were analyzed for growth and photosynthetic components during early growth and compared with their respective parents. Growth in terms of shoot length, fresh weight and dry weight along with the chlorophylls, and Hill activity revealed better parental and/or mid parental heterosis in all the hybrids over their respective parents. However, PEPcase activity displayed heterosis only in BJ-104. In other two hybrids no heterosis over the parents could be observed indicating thereby that the activity of this enzyme may not be rate limiting in parental lines.
Nevertheless, it appears that in pearl millet hybrids improved photosynthetic apparatus as observed in chlorophyll contents and Hill reaction may be one of the early expressions of hybrid vigour.