BIOLOGICAL VALUE OF PROTEINS OF MILK OF SIMMENTAL COWS PRODUCED UNDER CONDITIONS OF INTENSIVE TECHNOLOGY

Taking into account modern requirements, the biological value of the protein component of the Simmental breed Krov milk produced under intensive technology has been studied. The amino acid composition of milk proteins was identified by high-performance liquid chromatography. To analyze the biological value of proteins, calculated indicators were used: the amino acid index and the amino acid number (skor) of essential amino acids, taking into account the true digestibility of each of them. As a result of the research, all the essential and interchangeable amino acids and a fairly high concentration of many of them were identified. Among the essential amino acids, the largest amount in the milk samples contained phenylalanine+tyrosine, leucine, lysine, valine, and the smallest-tryptophan, methionine+cysteine. In the aggregate of interchangeable amino acids, the highest saturation was noted for glutamic acid+glutamine, arginine, proline, and the lowest-glycine, alanine. The predominance of interchangeable amino acids was noted in the protein component, which caused a low amino acid index (0.61). The amount of assimilated essential amino acids was higher relative to the reference protein. However, the amino acid score had a wide oscillation amplitude: from 149.6 % for the amino acids phenylalanine + tyrosine to 61.2 and 87.8 %, respectively, for tryptophan and methionine+cysteine, which indicated their imbalance. The essential amino acids tryptophan and methionine+cysteine were limiting, since their amino acid number (skor) is below 100 %.

Relationship between Free Amino Acid Index and Burnt-Mellow-Sweet Aroma Style Intensity of Flue-Cured Tobacco Leaves

80 samples of flue-cured tobacco leaves in Ganzhou area, Jiangxi Province in China were selected, relationships between free amino acid index and burntmellow- sweet aroma style intensity of leaves were studied with correlation analysis and stepwise regression analysis. In contrast to the content of Trp, Ile, Ser, Cys, β-Ala, Lys and the ratio of β-AiBA/TFAA, the content of Asp, Ala, Gly, Leu, β-AiBA and the ratio of Trp/TFAA, Ile/TFAA, Val/TFAA, Thr/TFAA, Ser/TFAA, Cys/TFAA, Asn/TFAA, β-Ala/TFAA, Lys/TFAA and Pro/TFAA in fluecured tobacco leaves had extremely significant positive correlation with burntmellow- sweet aroma style intensity. There was a significant negative correlation between burnt-mellow-sweet aroma style intensity and the content of Phe, Tyr, Asn, γ-ABA. 31 free amino acid indexes including the content of Asp, Glu, Phe etc. and the ratio of Glu/TFAA, Phe/TFAA, Trp/TFAA, etc. were main free amino acid index influencing burnt-mellow-sweet aroma style intensity of flue-cured tobacco leaves, which jointly decides 99.1% of variation of burnt-mellow-sweet aroma style intensity.

Effect of Light Intensity and Wavelength on Biomass Growth and Protein and Amino Acid Composition of Dunaliella salina

Dunaliella salina is a halotolerant, photoautotrophic marine microalga and one of the richest sources of natural carotenoids but also shows potential as a novel food source with high protein quality. This study sought to optimise the production of biomass, protein and amino acids from D. salina, alongside carotenoids using a two-stage cultivation approach based on the use of light of different intensities and quality, i.e., white, red and blue LED light. In stage 1, four white LED light intensities were tested. In stage 2, the same four light intensities from either blue or red LEDs were applied once exponential growth ceased and cells reached the stationary phase under white LED light in stage 1. Remarkably, both biomass concentration and biomass productivity showed a 1.3–1.7-fold increase in stage 2, without medium replenishment, while protein concentration and protein productivity showed an ~1.1-fold increase. The amino acid content and amino acid index remained unchanged from stage 1 to stage 2, and minimum difference was found across different light intensities. Overall, D. salina delivered so-called high protein quality, with an essential amino acid index (EAAI) of 0.99, and red light, which has previously been shown to increase carotenoid production, boosted further biomass production over and above white light, at all light intensities tested.

A comparative study on the physico-chemical quality indices of whole, commercial and refined wheat flours: Emphasis on essential amino acid index for three major penaeid shrimp species cultured in India

The physico-chemical characteristics of three different types of refined wheat flours (RWF-1, RWF-2 and RWF-3) were assessed to ascertain its suitability in shrimp feed along with three different types of whole (WWF-1, WWF-2 and WWF-3) and commercial (CWF-1, CWF-2 and CWF-3) wheat flours, and the essential amino acid index (EAAI) was determined based on the dietary requirement of three major penaeid shrimp species cultured in India viz., Penaeus vannamei, Penaeus indicus and Penaeus monodon. Results revealed that the fineness of WWF and RWF was 100% and alcoholic acidity exceeded an ideal level of 0.1% in WWF-2, CWF-3 and RWF-1. RWF had a low (p<0.05) water absorption (51.88-53.93%) and high bulk density (782.92-794.92 g l-1) compared to others. The moisture content was high (p<0.05) in RWF, whereas carbohydrate, protein, lipid and ash were found to be high in WWF. Of all the analysed samples, RWF had a higher (p<0.05) content of wet (28.56-31.82%) and dry (8.90-10.44%) glutens. Among the essential amino acids (EAA), arginine, lysine and methionine did not vary between the samples tested, while others showed significant (p<0.05) difference. EAAI was affected by the species (p=<0.001) but not by the flours (p = 0.173) and their interactions (p = 0.468). Both P. vannamei and P. indicus had a significantly higher EAAI (0.899 and 0.900, respectively) compared to P. monodon (0.862). Regression analysis showed a positive higher correlation between protein and EAA (r = 0.851) but EAA and its index were negatively correlated (r = 0.3464). Calories from carbohydrates were high in RWF (79.04-81.19%), but the reverse was true for protein and lipid in both WWF and CWF. Results conclude that RWF could be used for shrimp feed production, but ascertaining the processing effect on its utility by shrimps is essential.

Integration of Residue Attributes for Sequence Diversity Characterization of Terpenoid Enzymes

Progress in the “omics” fields such as genomics, transcriptomics, proteomics, and metabolomics has engendered a need for innovative analytical techniques to derive meaningful information from the ever increasing molecular data. KNApSAcK motorcycle DB is a popular database for enzymes related to secondary metabolic pathways in plants. One of the challenges in analyses of protein sequence data in such repositories is the standard notation of sequences as strings of alphabetical characters. This has created lack of a natural underlying metric that eases amenability to computation. In view of this requirement, we applied novel integration of selected biochemical and physical attributes of amino acids derived from the amino acid index and quantified in numerical scale, to examine diversity of peptide sequences of terpenoid synthases accumulated in KNApSAcK motorcycle DB. We initially generated a reduced amino acid index table. This is a set of biochemical and physical properties obtained by random forest feature selection of important indices from the amino acid index. Principal component analysis was then applied for characterization of enzymes involved in synthesis of terpenoids. The variance explained was increased by incorporation of residue attributes for analyses.