Characterization and comparison of antioxidant properties and bioactive components of virginia soybeans

Inhibitory activity of soybean (Glycine max L. Merr.) Cell Culture Extract on tyrosinase activity and melanin formation in alpha-melanocyte stimulating Hormone-Induced B16-F10 melanoma cells

BACKGROUND

Hyperpigmentation, which causes excessive melanin synthesis and accumulation, is an important issue in the cosmetic industry. Since compounds developed against hyperpigmentation often come with side effects such as skin irritation and contact dermatitis, new studies focus on the use of natural agents that have no side effects.

METHODS AND RESULTS

In this study, it was found that the effects of soybean cell culture extract (SCE) on alpha-melanocyte-stimulating hormone (α-MSH) induced melanogenesis in B16-F10 murine melanoma cells. The cells were incubated with SCE for 48 h after treatment with α‑MSH for 24 h to analysis the melanin content, cellular tyrosinase activity, and gene and protein expression. SCE at 1 mg/mL decreased melanin content and tyrosinase activity by 34% and 24%, respectively, compared to the α-MSH-treated group, which did not decrease cell viability. In addition, SCE (1 mg/mL) downregulated the expression of tyrosinase (TYR), tyrosinase-related protein (TRP)-1, tyrosinase-related protein (TRP)-2, and microphthalmia-associated transcription factor (MITF) genes 1.5-, 1.5-, 2-, and 2-fold, respectively. Furthermore, SCE inhibited the expression of TYR, TRP1, and TRP2 by decreasing the expression of MITF, as shown in a western blot assay.

CONCLUSIONS

This study suggests that SCE reveals dose-dependent inhibition of melanin synthesis through the suppression of tyrosinase activity as well as molecular levels of TYR, TRP1, TRP2, and MITF in B16-F10 murine melanoma cells. Therefore, SCE has the potential to be an effective and natural skin-whitening agent for application in the cosmetic industry.

Metabolite Contents and Antioxidant Activities of Soybean (Glycine max (L.) Merrill) Seeds of Different Seed Coat Colors

Seed coat color is one of the main agronomical traits that determine the chemical quality of soybean seeds and has been used as a parameter during cultivar development. In this study, seeds of yellow (n = 10), greenish-yellow (n = 5), and light-yellow (n = 4) soybean accessions were evaluated for their contents of total protein, total oil, total phenolic (TPC), and five prominent fatty acids including palmitic acid (PA), stearic acid (SA), oleic acid (OA), linoleic acid (LA), and linolenic acid (LLA), relative to a control cultivar, and the effect of seed coat color on each was investigated. Antioxidant activity was also evaluated using 1,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP). The results showed significant variations of metabolite contents and antioxidant activities between the soybeans. The average TPC, DPPH-radical scavenging activity, and FRAP were each in the order of greenish-yellow > yellow > light-yellow soybeans. In contrast, light-yellow soybeans contained a high level of OA and low levels of SA, LA, and LLA, each except LA differing significantly from yellow and greenish-yellow soybeans (p < 0.05). Our findings suggest that greenish-yellow and light-yellow soybeans could be good sources of antioxidants and high-quality soybean oil, respectively.

Phosphate Fertilizer and Growing Environment Change the Phytochemicals, Oil Quality, and Nutritional Composition of Roundup Ready Genetically Modified and Conventional Soybean

Phosphorus (P) intake, genotype, and growth environment in soybean cultivation can affect the composition of the soybean. This experiment was conducted in two locations (microregions I and II) using a randomized complete block design, including conventional soybean (BRS Sambaíba) and genetically modified (GM) [Msoy 9144 Roundup Ready (RR)] cultivars and varying doses of phosphorus fertilizer (0, 60, 120, and 240 kg/ha P2O5). Soybeans were evaluated for chemical composition, total phenols, phytic acid content, individual isoflavone content, antioxidant activity, oil quality, fatty acid profile, total carotenoid content, and individual tocopherol contents. Multivariate analysis facilitated reduction in the number of variables with respect to soybean genotype (conventional BRS Sambaíba and GM Msoy 9144 RR), dose of P2O5 fertilizer, and place of cultivation (microregion I and II). BRS Sambaíba had higher concentrations of β-glucosides, malonylglucosides, glycitein, and genistein than Msoy 9144 RR, which showed a higher concentration of daidzein. The highest concentrations of isoflavones and fatty acids were observed in soybeans treated with 120 and 240 kg/ha P2O5, regardless of the location and cultivar.

Analysis of isoflavone, phenolic, soyasapogenol, and tocopherol compounds in soybean [ Glycine max (L.) Merrill] germplasms of different seed weights and origins

This study investigated the functional compounds, including isoflavones, phenolics, soyasapogenols, and tocopherols, that were detected in 204 soybean [ Glycine max (L.) Merrill] germplasms. The soybean samples were divided into three groups according to origin: America, China, and Korea. The soybean samples were also classified into three groups on the basis of 100-seed weight: small (<13 g), medium (13-24 g), and large (>24 g). Among the soybean germplasms, CSRV121 (Bosukkong) had the highest level of isoflavone content (4778.1 μg g(-1)), whereas CS01316 had the lowest isoflavone content (682.4 μg g(-1)). Of the soybeans from the three different countries of origin, those from Korea showed the highest average concentration of total isoflavones (2252.6 μg g(-1)). The small seeds had the highest average total isoflavone concentration (2520.0 μg g(-1)) of the three different seed sizes. Among the 204 soybean germplasms, CS01405 had the highest content of total phenolics (5219.6 μg g(-1)), and CSRV017 (Hwangkeumkong) had the lowest phenolic content (654.6 μg g(-1)). The mean concentrations of total phenolic compounds were 2729.1 μg g(-1) in American soybean seeds, 1680.4 μg g(-1) in Chinese soybean seeds, and 1977.6 μg g(-1) in Korean soybean seeds. Of the soybean seeds from the three different countries of origin, American soybean seeds had the highest average concentration of total phenolic compounds, and Korean varieties showed the second highest value. Small soybean seeds had the highest average content of total phenolic compounds (2241.7 μg g(-1)), whereas medium-sized (1926.8 μg g(-1)) and large (1949.9 μg g(-1)) soybeans had lower concentrations of phenolic compounds. In whole soybean germplasms, the level of total soyasapogenols was higher in CS01173 (1802.3 μg g(-1)) and CS01346 (1736.8 μg g(-1)) than in the other types of soybeans. The mean concentrations of total soyasapogenol were 1234.0 μg g(-1) in American, 1294.5 μg g(-1) in Chinese, and 1241.5 μg g(-1) in Korean soybean varieties. Chinese soybean varieties showed the highest mean concentration of total soyasapogenol, and Korean soybean seeds showed the second highest level. The medium-seed group had the highest soyasapogenol content (1269.3 μg g(-1)) of the seeds that were grouped by size. A larger amount of soyasapogenol B than soyasapogenol A was detected. In whole soybeans, CS01202 showed the highest level of total tocopherols (330.5 μg g(-1)), whereas CSRV056 (Pungsannamulkong) had the lowest content (153.3 μg g(-1)). Chinese soybeans had the highest average concentration of total tocopherols (255.1 μg g(-1)). By comparison, the medium-sized Chinese soybean group had the highest (256.1 μg g(-1)) average total tocopherol content.

Production and functional characterisation of antioxidative hydrolysates from corn protein via enzymatic hydrolysis and ultrafiltration

Corn protein was hydrolysed by three microbial proteases and further separated by sequential ultra-filtration to 12 hydrolysate fractions which were investigated for free radical scavenging capacity and chelating activity. The oxygen radical absorbance capacity (ORAC) of the hydrolysates varied significantly between 65.6 and 191.4μmoles Trolox equivalents (TE)/g dried weight with a small peptide fraction (NP-F3) produced by neutral protease (NP) possessing the highest antioxidant activity. The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH()) scavenging activities of the hydrolysate fractions also varied significantly between 18.4 and 38.7μmoles TE/g. Two fractions (AP-F2 and AP-F3) produced by alkaline protease (AP) showed the strongest activity. However, no significant difference was detected on the chelating activity of the fractions. NP-F3, AP-F2, and AP-F3 were incorporated into ground beef to determine their effects on lipid oxidation during 15-day storage period. NP-F3 was the only fraction that inhibited lipid oxidation at both 250 and 500μg/g levels by as much as 52.9%.

Isoflavone composition, total polyphenolic content, and antioxidant activity in soybeans of different origin

Twenty soybean cultivars, originating from the United States, Russia, Serbia, and China, were analyzed for their isoflavone composition, total polyphenolic content, and antioxidant activity. Isoflavones were extracted by aqueous methanol (80%) and analyzed by high-performance liquid chromatography/diode array detection. Precision and linearity of the applied method were within the standard limits of validation. The highest and the lowest total isoflavone contents were 4.59 and 1.45 mg/g of dried soybean weight, respectively. A significant difference (P < .05) was found in isoflavone concentration among the different cultivars, but it was observed that origin is not a significant factor that could influence isoflavone content in soybeans. Total polyphenolic content varied between 2.13 and 3.45 mg of gallic acid equivalents/g of dried soybean weight. The free radical scavenging activity of soybean extracts assayed by 2,2-diphenyl-1-picrylhydrazyl in terms of 50% inhibitory concentration (IC(50)) ranged from 1.40 to 3.35 mg/mL. Negative correlation between total polyphenolic content and IC(50) was observed, but there was no correlation between total isoflavone content and IC(50). On the basis of this study, soybean cultivars with larger potency for biological activity could be recognized.

Comparison of different strategies for soybean antioxidant extraction

Three extraction strategies including Soxhlet extraction, conventional solid-liquid extraction, and ultrasonic-assisted extraction (UAE) were compared for their efficiency to extract phenolic antioxidants from Virginia-grown soybean seeds. Five extraction solvents were evaluated in UAE and the conventional extraction. The soybean extracts were compared for their total phenolic contents (TPC), oxygen radical absorbance capacity (ORAC), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) scavenging activities. The results showed that UAE improved the extraction of soybean phenolic compounds by >54% compared to the conventional and Soxhlet extractions. Among the tested solvents, 50% acetone was the most efficient for extracting soybean phenolic compounds. There was no significant correlation between the TPC and antioxidant activities of the soybean extracts. The extracts prepared by 70% ethanol had the highest ORAC values. Overall, UAE with 50% acetone or 70% ethanol is recommended for extracting soybean antioxidants on the basis of the TPC and ORAC results.