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Escalating diabetes, obesity, cardiovascular disease, and bowel syndrome have increased consumer awareness of nutrition and energy values of starch products. Slowly digestible starch (SDS), slowly digestible maltooligosaccharides (SDM), and highly branched maltooligosaccharides, so called isomaltooligosaccharides (IMOs), generated by enzyme modification of starch, provide a new concept to meet consumer demands and solve urgent health‐associated problems. The combination of starch‐active enzymes in the glucanotransferase and glucanohydrolase families to produce slowly digestible‐ and non‐digestible α‐glucans has been widely studied, mainly focusing on the activities of branching enzyme (BE), amylomaltase (AM), and α‐transglucosidase (TGase). Products obtained from the action of these enzymes have resulted in completely novel types of maltooligosaccharides that are slowly degraded and therefore digested in the small intestine to maintain regulated blood glucose levels and suppressed glycemic‐index response. Some IMOs can even escape the small intestine and become fermented by micro‐organisms in the large intestine to produce health‐promoting short‐chain fatty acids such as butyric acid. Such slowly digested α‐glucans can regulate and trigger health‐promoting gut hormone release. Different novel production strategies of health‐promoting α‐glucans, their structures and nutritional effects are discussed here. [ABSTRACT FROM AUTHOR]

BACKGROUND The water unextractable arabinoxylans ( WUAX) contain beneficial phenolic compounds that can be used for food rather than for animal feed. The antioxidant activities of defatted rice bran obtained by xylanase-aided extraction is reported herein. The chemical and molecular characteristics of extracted fractions were investigated. RESULTS The WUAX hydrolysate precipitated by 0-60% ethanol ( F60), 60-90% ethanol ( F6090), and more than 90% ethanol ( F90) had decreased molar masses with increasing ethanol concentration. The fractions of interest, F60 and F6090, contained 75% arabinoxylans with ferulic acid as the major bound phenolic acid, followed by p-coumaric acid. According to chemical-based antioxidant assays F60 and F6090 exhibited higher diphenyl-1-picrylhydrazyl ( DPPH) radical scavenging and ferric iron reducing ability than F90 which contained minor contents of small sugars and free phenolic acids. In cell-based antioxidant assays, using the fluorescent 2′,7′-dichlorofluorescein diacetate probe, all three fractions were potent intracellular scavengers. CONCLUSION The high molar mass of WUAX hydrolysates with high amount of bound phenolics contributes to the chemical-based antioxidant activity. All fractions of WUAX hydrolysates showed high potent intracellular scavenging activity regardless of molar mass, content and the component of bound phenolics. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In Job's tear, the germ is enfolded inside the kernel and comprises ca. one third of the whole grain. To assess the effect of germ on flour properties, degermed flour was manually prepared from grains of white and black husk cultivars. The protein of whole grain and degermed flours was not ignificantly different (p > 0.05). The antioxidant properties, which were total phenolic content, DPPH radical scavenging and reducing power, and coixenolide of whole grain and degermed flours of both cultiva·s were in the ranges of 7.33-8.18 mgGAE/g, 5.40-7.53%, 2.56-2.88 and 0.02-0.53 pglg, respectively. The Job's tear sta·ch granules showed a round and polyglonal shape and their average size was 11.68-12.29 pm. The gelatinization temperature range of white and black Job's tear starch was 67-8l"C and the retrogradation behavior of Job's tear starch occurred after storage at 4"C for 39 days as monitored by differential scanning calorimetry. The peak viscosity of the white Job's tear flours was greater than those of the black cultivar flours but the setback and pasting temperature was lower. The swelling power of the white Job's tear flours was higher than that of the black cultivar flours, but their solubility was lower and the opposite result was found in the starch. [ABSTRACT FROM AUTHOR]

The effect of dehydration methods on the fractions of rapidly digestible starch (RDS), slowly digestible starch (SDS), and resistant starch (RS) was studied. The rice starch suspension was gelatinized and debranched with pullulanase for 24 h. The debranched rice starch (DBRS) was subjected to aging for 48 h with time temperature cycling treatment with temperatures of 30 and 80°C. After aging, the DBRS was dehydrated using various dehydration conditions and methods: 10 and 24% solid with temperatures of 120 and 140°C for drum drying, 10% solid with inlet temperatures of 150 and 170°C and outlet temperatures of 90 and 110°C for spray drying, and 24% solid with 50°C for 10 h and 80°C for 8 h for hot air oven drying. The lower RS content and the higher RDS and SDS content were observed in all dehydration conditions as compared with the fresh sample before dehydration. The spray drying method showed the highest RS of 43%, the lowest RDS of 15% and SDS of 18%, and the melting temperature of 82-110°C, while the dehydration using the hot air oven and drum drying demonstrated the RS content of 39% and 36%, the SDS content of 20% and 21%, and the RDS content of 16% and 17%. The drum drying method exhibited an A+V type crystalline structure with the minimum relative crystallinity of 19% and the maximum melting temperature of 116-123°C, while that of the other dehydration methods illustrated the B+V type. [ABSTRACT FROM AUTHOR]

The protein characteristics of fresh and aged rice were investigated to correlate with the textural and pasting properties. The alkaline extractable proteins of aged rice were lower than those of fresh rice and they were extensively decreased in cooked rice. However, an increase in extractable proteins was noticed when the extraction buffer contained 1% sodium dodecyl sulfate, indicating that the rice proteins were stabilized via hydrophobic interaction. The extracted proteins from raw and aged cooked rice showed higher surface hydrophobicity and more disulfide bonds than those of fresh rice, suggesting more protein unfolding and higher disulfide linkages. In addition, aged rice proteins revealed higher molecular weight formed via disulfide bonds and hydrophobic interactions, as observed by sulfate polyacrylamide gel electrophoresis (SDS-PAGE). After cooking, increased proglutelin and new aggregated protein (41 kDa) were observed. The harder texture and lower stickiness of aged cooked rice were noticed as compared with fresh cooked rice. Aged flour showed a lower breakdown, higher setback, and less paste viscosity, as monitored with a Rapid Visco Analyser. Removing protein from aged and fresh flour showed similar pasting curves, indicating that the proteins' characteristics had an influence on the pasting characteristics and were related to the cooked rice's texture. [ABSTRACT FROM AUTHOR]

Mung bean starch is distinguished by its exceptional high amylose content and regulation of starch biosynthesis in leaves and storage tissues, such as seeds, share considerable similarities. Genetic engineering of starch composition and content, requires detailed knowledge of starch biosynthetic gene expression and enzymatic regulation. In this study we applied detailed transcriptomic analyses to unravel the global differential gene expression patterns in mung bean leaves and in seeds during various stages of development. The objective was to identify candidate genes and regulatory mechanisms that may enable generation of desirable seed qualities through the use of genetic engineering. Notable differences in gene expression, in particular low expression of the Protein Targeting to Starch (PTST), starch synthase (SS) 3, and starch branching enzyme1 (SBE1) encoding genes in developing seeds as compared to leaves were evident. These differences were related to starch molecular structures and granule morphologies. Specifically, the starch molecular size distribution at different stages of seed development correlated with the starch biosynthesis gene expression of the SBE1, SS1, granule-bound starch synthases (GBSS) and isoamylase 1 (ISA1) encoding genes. Furthermore, putative hormonal and redox controlled regulation were observed, which may be explained by abscisic acid (ABA) and indole-3-acetic acid (IAA) induced signal transduction, and redox regulation of ferredoxins and thioredoxins, respectively. The morphology of starch granules in leaves and developing seeds were clearly distinguishable and could be correlated to differential expression of SS1. Here, we present a first comprehensive transcriptomic dataset of developing mung bean seeds, and combined these findings may enable generation of genetic engineering strategies of for example starch biosynthetic genes for increasing starch levels in seeds and constitute a valuable toolkit for improving mung bean seed quality., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Umnajkitikorn, Boonchuen, Senavongse, Tongta, Tian, Hu, Petersen and Blennow.)