Genetic diversity and stability in starch physicochemical property traits of potato breeding lines.

Cross breeding may create wider genetic variation than two parents used in hybridization, but breeding efforts towards starch quality improvement are less reported in potato. A cross was made between Zhongshu-3 and Favorita to select desired starch properties in progenies. Among 206 F1 clones with potential high yield, starch qualities such as apparent amylose content (AAC), pasting viscosity, and thermal properties were further evaluated. A wide variation was observed in different starch physicochemical indices for 206 potato accessions. Twenty clones with high/low AAC, peak viscosity and peak gelatinization temperature were selected and then grown at another location to evaluate the stability of the traits. Similar wide range of variation in the starch properties was observed. Cluster analysis based on starch properties of the 20 selected clones indicating relative stability of the starch property traits across different locations. New breeding lines identified have potential for application in food and other industries.

Genetic diversity of potato genotypes estimated by starch physicochemical properties and microsatellite markers.

Genetic diversity of 29 potato genotypes was estimated by their starch physicochemical properties and microsatellite markers. The apparent amylose content (AAC) of potato starches averaged 25.3%, ranging from 18.9 to 29.4%. Significance differences were observed in pasting and gel texture properties among potato accessions. Wide genetic diversity was also found in the gelatinization temperatures (To, Tp, Tc), enthalpies of gelatinization, enthalpies of retrogradation and retrogradation percentage, which had ranges of 62.2-67.6 °C, 66.1-71.1 °C, 73.5-77.4 °C, 17.5-21.0 J/g, 1.95-4.41 J/g, and 10.6-21.4%, respectively. AAC had significant correlation with pasting viscosities and gel hardness, but had no correlation with thermal and retrogradation properties. The grouping of the potato genotypes using 30 microsatellite markers did not correspond to that drawn using the starch physicochemical properties. Molecular analysis revealed that genotypes with interesting starch properties were distributed among three clusters. Potato starches exhibited interesting physiochemical properties could be applied in food and industrial applications.

Bound phenolic compounds and antioxidant properties of whole grain and bran of white, red and black rice.

Total phenolic content (TPC), individual phenolic acid and antioxidant capacity of whole grain and bran fraction 18 rices with different bran color were investigated. The levels of TPC in bound fractions were significantly higher than those in the free fractions either in the whole grains or brans. The main bound phenolic acids in white rice samples were ferulic acid, p-coumaric acid, and isoferulic acid, and in pigmented rice samples were ferulic acid, p-coumaric acid, and vanillic acid. The protocatechuic acid and 2,5-dihydroxybenzoic acid were not detected in white samples. The content of gallic acid, protocatechuic acid, 2,5-dihydroxybenzoic acid, ferulic acid, sinapic acid had significantly positive correlations with TPC and antioxidant capacity. This study found much wider diversity in the phenolics and antioxidant capacity in the whole grain and brans of rice, and will provide new opportunities to further improvement of rice with enhanced levels of the phytochemicals.

Antiglycation therapy: Discovery of promising antiglycation agents for the management of diabetic complications.

CONTEXT: During diabetes mellitus, non-enzymatic reaction between amino groups of protein and carbonyl of reducing sugars (Millard reaction) is responsible for the major diabetic complications. Various efforts have been made to influence the process of protein glycation. OBJECTIVES: This review article provides an extensive survey of various studies published in scientific literature to understand the process of protein glycation and its measurement. Moreover, evaluation and identification of potential inhibitors (antiglycation agents) of protein glycation from natural and synthetic sources and their mechanism of action in vitro and in vivo are also addressed. METHOD: In this review article, the mechanism involved in the formation of advanced glycation end products (AGEs) is discussed, while in second and third parts, promising antiglycation agents of natural and synthetic sources have been reviewed, respectively. Finally, in vivo studies have been addressed. This review is mainly compiled from important databases such as Science, Direct, Chemical Abstracts, SciFinder, and PubMed. RESULTS: During the last two decades, various attempts have been made to inhibit the process of protein glycation. New potent inhibitors of protein glycation belonging to different classes such as flavonoids, alkaloids, terpenes, benzenediol Schiff bases, substituted indol, and thio compounds have been identified. CONCLUSION: Antiglycation therapy will be an effective strategy in future to prevent the formation of AGEs for the management of late diabetic complications Current review article highlighted various compounds of natural and synthetic origins identified previously to inhibit the protein glycation and formation of AGEs in vitro and in vivo.