Effects of germination combined with extrusion on the nutritional composition, functional properties and polyphenol profile and related in vitro hypoglycemic effect of whole grain corn

Guo

et al. 2020

Preprint

Self Cite

The polyphenol distribution in fresh waxy corns of different color varieties and their functional activities, which may be useful for treating various chronic diseases, were investigated. The in vitro antioxidant activity, and hypoglycemic and hypocholesterolemic effects of the free and bound corn phenolics were determined to evaluate the edible value of fresh waxy corn. The colored varieties contained more phenols than the common varieties (white and/or yellow). The total free phenolic acid content of the six varieties was 6637.73 μg/g DW (dry weight), which was slightly higher (P >0.05) than that of the total bound form (6276.65 μg/g DW). The total free flavonoid content was 5850.09 μg/g DW, which was higher (P < 0.05) than that of the total bound form (4874.51μg/g DW). No bound anthocyanin was detected in the methanol extracts of the tested varieties. For all the varieties, free polyphenols contributed 86-100% and 70-78% of the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging abilities, respectively, and 100% of the ferric reducing capacity. The free phenolics in fresh waxy corn showed significantly better (P < 0.05) hypoglycemic effect than the bound form in terms of inhibition of α-amylase activity, whereas the bound phenolics of most varieties showed higher α-glucosidase inhibitory activity than the free forms. The free phenolics showed significantly better (P < 0.05) glycocholesterol binding than the bound form for all varieties. The bound polyphenols showed better sodium cholate and taurocholate binding than the free form for most varieties. In conclusion, the difference between free and bound polyphenol content and functional activities indicates that fresh waxy corn can be potentially used for the development of functional food.Keywords: fresh waxy corn; polyphenol; antioxidant activity; hypoglycemic; hypocholesterol

Section: In Vitro Chemical Antioxidant Activity Of Polyphenol Extractmentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

Phenolics and related in vitro functional activities of different varieties of fresh waxy corn: a whole grain

Guo

et al. 2020

Preprint

Self Cite

“…Free and bound phenolics were extracted according to previous method [14]. The samples (5 g) were ground to flour and mixed with 100 mL chilled acidified methanol (95% methanol and 1M HCl 85:15, v/v).…”

Section: Extraction Of Free and Bound Phenolicsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Phenolics and related in vitro functional activities of different varieties of fresh waxy corn: a whole grain

Guo

et al. 2019

Preprint

Self Cite

The polyphenol distribution in fresh waxy corns of different color varieties and their in vitro functional activities, which may be useful for treating various chronic diseases, were investigated. The colored varieties contained more phenols than the common varieties (white and/or yellow). The total free phenolic acid content of the six varieties was 3151.57 μg/g DW (dry weight), which was slightly higher ( p >0.05) than that of the total bound form (3028.24 μg/g DW). The total free flavonoid content was 5850.09 μg/g DW, which was higher ( p < 0.05) than that of the total bound form (4874.51μg/g DW). No bound anthocyanin was detected in the methanol extracts of the tested varieties. For all the varieties, free polyphenols contributed 86-100% and 70-78% of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging abilities, respectively, and 100% of the ferric reducing capacity. The free phenolics in fresh waxy corn showed significantly better ( p < 0.05) hypoglycemic effect than the bound form in terms of inhibition of α-amylase activity, whereas the bound phenolics of most varieties showed higher α-glucosidase inhibitory activity than the free forms. The free phenolics showed significantly better ( p < 0.05) glycocholesterol binding than the bound form for all varieties. The bound polyphenols showed better sodium cholate and taurocholate binding than the free form for most varieties. In conclusion, the difference between free and bound polyphenol content and functional activities indicates that fresh waxy corn can be potentially used for the development of functional food.

“…Polyphenols not only have a strong antioxidation characteristic [2] but also have anticancer [3], bacteriostatic [4], liverprotecting [5], anti-infection [6], cholesterol lowering [7], and immunity enhancement [8] properties, and they also prevent various biological activities such as type 2 diabetes [9,10]. As far as their formation mechanism is concerned, most polyphenols are the secondary metabolites of the phenylpropanoid biosynthesis pathway, which are also known as phenyl propane compounds [11]. Polyphenols and polyphenol-enriched by-products have been widely used in bakery foods because of their nutraceutical properties.…”

Section: Introductionmentioning

confidence: 99%

Functional Properties of Polyphenols in Grains and Effects of Physicochemical Processing on Polyphenols

Tian

Sun

Journal of Food Quality

et al. 2019

Phenolic compounds are important products of secondary metabolism in plants. They cannot be synthesized in the human body and are mainly taken from food. Cereals, especially whole grains, are important sources of dietary polyphenols. Compared with vegetables and fruits, the content and biological activities of polyphenols in cereals have long been underestimated. Polyphenols in whole grains are non-nutritive compounds, which are distributed in all structural areas of cereal substances, mainly phenolic acids, flavonoids, and lignans. In recent years, the health effects of whole grains are closely related to their phenolic compounds and their antioxidant activities. Now, different physicochemical processing treatments and their effects have been summarized in order to provide the basis for promoting the development and utilization of food. The various functions of whole grains are closely related to the antioxidant effect of polyphenols. As the basic research on evaluating the antioxidant effect of active substances, in vitro antioxidant tests are faster and more convenient.