Fatty Acid Characteristics of Triacylglycerols and Phospholipids in Adzuki Beans (Vigna angularis)

Abstract

Fatty acid distribution of triacylglycerols and phospholipids isolated from five cultivars of adzuki beans (Vigna angularis) was investigated. Lipids were separated by TLC into eight subfractions. The lipid components comprised mainly phospholipids and triacylglycerols. The phospholipid components included phosphatidylcholine, phoshatidylinositol, and phosphatidylethanolamine. Comparison of these different cultivars showed, with a few exceptions, no significant differences in fatty acid distribution. Fatty acid distribution of triacylglycerols among the five cultivars was characterized as: unsaturated fatty acids predominantly concentrated at the sn-2 position and saturated fatty acids primarily occupying the sn-1 or sn-3 position in the lipids. These results should be useful information to both producers and consumers for manufacturing of traditional adzuki confectionaries (wagashi or an paste) in particularly Japan.Keywords: adzuki beans (Vigna angularis), phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, fatty acid distributions, triacylglycerols *To whom correspondence should be addressed. E-mail: yoshida@nutr.kobegakuin.ac.jp IntroductionSome beans are used as staple foods in many countries, and are increasing in attention as a preventive agents against coronary heart disease ( Anderson et al., 1984, Bazzano et al., 2001. Adzuki or small red beans (Vigna angularis) are a popular ingredient in many confections in East Asia. The predominant use of adzuki in traditional Japanese confections is an paste or wagashi including youkan, manju and amanatto (Hoshikawa, 1985;Shi, 1988). Adzuki beans are a rich source of carbohydrates, proteins, vitamins, minerals and fiber; however, they also contain antinutritional factors. Phytates, α-galactosides and trypsin inhibitors are among these factors, and their concentrations differ widely among adzuki bean cultivars. When adzuki beans are prepared for use in confectionaries, they are boiled to yield a hot water extract as a byproduct. This byproduct contains its active ingredients. The 40% (w/v) ethanol fraction of hot-water adzuki bean extract is known to suppress proliferation of human stomach cancer cells in culture, as well as benzo(α)pyrene-induced tumorigenesis in the mouse forestomach (Itoh et al., 2004). In fact, the hot-water adzuki bean extract has numerous effects (Hori et al., 2009). Wu et al. (2004 have shown that a watersoluble extract of the adzuki bean could inhibit acetaminophen-induced liver damage.In Western countries, fat consumption is shifting from food products containing animal fats to those containing vegetable oil due to the potential effect of saturated fatty acids (FA) on obesity, atherosclerosis, coronary heart disease, and myocardial infarction. A previous study has attempted to investigate the nutritional value of adzuki by determining the chemical composition of the whole seed (Hsieh et al., 1992). However, to the best of our knowledge, no data are available on the lipid components and FA composition of adzuki beans. There...

Exploration of natural phosphatidylcholine sources from six beans by UHPLC‐Q‐HRMS

“…In a previous work, two fatty acids were identified from PC of adzuki bean, namely, 16:0 and 18:2, which was the most abundant fatty acids (Yoshida, Yoshida, Tomiyama, & Mizushina, 2010). In our study, we have identified the same fatty acids, however, C18:1n9c was the most abundant one.…”

“…They accounted for 84.5% of total PC species. Several previous studies involved the determination of the fatty acid profiles of lipids including triacylglycerols and phospholipids from adzuki beans by GC analysis (Yoshida et al., 2010; Yoshida, Tomiyama, & Yoshida, 2010; Yoshida, Yoshida, & Tomiyama, 2008). However, GC analysis requires hydrolysis and derivatization of phospholipids, this procedure leads to loss the information about the chemical structure of the complete phospholipid molecules, while LC‐MS (liquid chromatography‐mass spectrometry) could provide the exact molecular structure information.…”

Suppression of Pancreatin-Induced Digestion of Starch in Starch Granules by Starch/Fatty Acid and Starch/Flavonoid Complexes in Retrograding Rice Flour

“…Oleic (C18:1), linoleic (C18:2), and linolenic (C18:3) acids were identified in the adzuki extract by the HPLC system described in Materials and Methods, and their concentrations in the extract were estimated to be 71.1 ± 12.8, 4.8 ± 1.4, and 3.6 ± 0.6 mM ( n = 3), respectively. Here, the concentration of oleic acid was much higher than that of linoleic acid, but it has been reported that the content of linoleic acid is greater than that of oleic acid in the adzuki bean [ 23 , 24 ]. Therefore, both oleic and linoleic acids were used here.…”