Identification of anthocyanins in black soybean (Glycine max (L.) Merr.) varieties

Abstract

Anthocyanin pigments in black soybean (Glycine max (L.) Merr.) varieties as Tawonkong (TW) and Geomjeongkong-2 (G2) were identified to evaluate their potentials as nutritional function, natural colorant or functional foods. Anthocyanin extraction was conducted with acidified methanol with 0.1 M HCl (85:15, v/v). Identification of anthocyanin was conducted by comparison with purified standards by HPLC and mass spectrometry (MS). G2 showed six different types of pigments by HPLC, whereas TW showed seven pigments. Three major anthocyanins (peaks 1, 3, 4) were detected in both varieties and peak 1 was characterized as delphinidin-3-O-β-D-glucoside, peak 3 as cyanidin-3-O-β-D-glucoside (C3G), and peak 4 as petunidin-3-O-β-D-glucoside by comparison of chromatographic properties with authentic standards and MS. Minor peaks 5, 6 and 7 in TW were tentatively identified as pelargonidin-3-Oglucoside, pelargonidin-3-O-(6″-malonylglucoside) and cyanidin on the basis of MS. MS with major ions at 287 and 449 of peak 2 were exactly same as those of peak 3 meaning that peak 2 has cyanidin and other hexose different from glucose. After acid hydrolysis of fractioned peak 2, HPLC showed the hexose as galactose, and peak 2 was identified as C3Glactose.The most abundant anthocyanin in black soybean (Glycine max (L.) Merr.) was C3G and G2 showed the higher amount of total anthocyanins than TW (p<0.001).

Isoflavone, anthocyanin, and fatty acid contents of vegetable-type soybean grains at different maturity stages

“…Anthocyanins were expressed in similar amounts as observed in Korean black-soybean-seed varieties (Koh et al, 2014). They were present only in line BRM09-50995, which shows a black seed coat.…”

“…Large grain size and mild flavor are the main quality criteria for vegetable-type soybean, whose grains are different of the so-called commodities cultivars. A profile of nine anthocyanins can be found in black soybean grains, which are affected by genetic and environmental conditions, but cyanidin-3-O-β-Dglycoside anthocyanin form is the major compound (Koh et al, 2014).…”

Effect of Black Soymilk Processing Conditions On Anthocyanins Content

“…Anthocyanins are flavonoids, red or purple color, recognized as health-promoting functional ingredients because of their antioxidant capacity [8]. Its profiles and contents can differ among varieties being cyanidin-3-glucoside the most abundant anthocyanins in investigated cultivars [9], [10].…”

“…Its profiles and contents can differ among varieties being cyanidin-3-glucoside the most abundant anthocyanins in investigated cultivars [9], [10]. Anthocyanins can also be greatly degraded by thermal processing and, once soybean must be thermally processed prior to be consumed, preparation methods need to be evaluated [11], [12].…”

Anthocyanin Recovery from Mangosteen (Garcinia mangostana L.) Hull using Lime Juice Acidified Aqueous Methanol Solvent Extraction

“…The latter protocol is more commonly used by researchers probably due to it being simple, fast and effective. It involves maceration or soaking of plant material in methanol containing a small concentration of mineral acid such as hydrochloric acid (HCl) (Burin et al, 2011;Du and Francis, 1977;González-Paramás et al, 2006;Koh et al, 2011;Palapol et of the mangosteen fruits change from green to purple black as they ripen (Du and Francis, 1977;Palapol et al, 2009). The preparation of dried mangosteen hull was as described by Cheok et al (2012) where small pieces of mangosteen hulls were dried under a fan at an ambient temperature of 28℃ for at least two days to achieve a moisture loss of about 48.5% from the initial weights measured.…”