Beom-Gyun Jeong

Nutritional and Functional Properties of Water Extracts from Achyranthes japonica Nakai-Rice Pilsner Byproducts

Two byproducts, brewer’s spent grain (BSG; germinated rice and malt) and brewer’s spent material (BSM; Achyranthes japonica Nakai), were collected during the manufacture of pilsner beer using A. japonica Nakai and germinated rice. Water extracts of BSG and BSM were prepared at different temperatures (25°C, 60°C, and 100°C) for 5 h, and their nutritional and functional properties were investigated. γ-Aminobutyric acid (GABA), saponin, and niacin contents were higher in extracts prepared at 60°C for more than 3 h than the other extracts, whereas total polyphenol content, DPPH radical scavenging activity, and reducing power were higher in samples extracted at 100°C for 1 h compared to the other ones. Overall, water extraction at 60°C for 3 h was desirable to effectively collect both nutritional and functional components from BSG and BSM. Under these conditions, BSM extracts showed 4∼18 times high niacin and folate contents, 1.4 times high total phenolic content, and 11∼60 times high antioxidant activities compared to BSG extracts. This study shows that pilsner beer byproducts would be good sources of health beneficial components, especially GABA, saponin, water soluble vitamins, and polyphenolics.

Variations in vitamin E, phenolic content, and antioxidant properties of different wheat cultivars of South Korea

ABSTRACT The vitamin E, total phenolic content (TPC), and antioxidant activity (AA) profiles of 32 whole wheat cultivars were investigated. Samples were classified based on its hardness (HW: hard wheat, MW: medium wheat, and SW: soft wheat) for easy identification. Total vitamin E content ranged from 64.38SW2 to 111.83MW9 mg/kg; α-tocopherol (6.03MW13 to 21.98MW2 mg/kg), β-T (2.14MW8 to 21.01MW9 mg/kg), α-tocotrienol (4.28MW12 to 9.34MW9 mg/kg), and β-T3 (38.71MW16 to 61.07MW9 mg/kg) were the predominant homologs, with β-T3 as the highest. AA ranged from 334.40MW4 to 584.80HW4 μmol gallic acid equivalent/kg while TPC varied from 1139.70SW6 to 2772.60MW1 μmol GAE/kg. Significant differences in the vitamin E content, TPC, and AA were found among the cultivars regardless of its hardness index. A very weak correlation was found between TPC and AA while a moderate negative correlation was observed between vitamin E content and AA. Results from this study can serve as basis of further studies on the bioactive profiles of Korean wheat cultivars.