In the current study, the functional and biochemical potential of the seeds of four persimmon cultivars (PC1, PC2, PC3 and PC4) and their role against oxidative stress and acetylcholinesterase (AChE) inhibition were evaluated. In terms of biochemical compositions, free amino acids, fatty acids and organic acids analysis was performed. The free amino acids ranged from 2617.31 (PC2) to 3773.01 μg∙g⁻¹ dry weight (PC4). Oleic acid and linoleic acid were the principal fatty acids, which were significantly higher in PC4 and PC1, respectively. PC4 presented the highest amount of organic acid content (4212 mg∙kg⁻¹), whereas PC2 presented the lowest (2498 mg∙kg⁻¹). PC2 contained higher total phenolic content and flavonoid content, whereas PC3 had the lowest amount as compared to other cultivars. The in vitro DPPH, ABTS and superoxide anion radicals scavenging activity increased in a dose-dependent manner, whereas PC2 showed significantly higher scavenging activities as compared to PC1, PC2 and PC4 types. In the case of AChE inhibition, PC4 showed a moderate activity (67.34% ± 1.8%). In conclusion, the current findings reveal that the studied persimmon seeds cultivars are a source of bioactive natural antioxidants and AChE inhibitors. Such natural products could be employed in pharmaceutical and food industries, whilst can also be considered for the treatment of neurodegenerative diseases such as Alzheimer’s.

Fermented soybeans, cheonggukjang (CKJ), are considered to be more wholesome than soybeans in Korea. To select the best soybean cultivar for making functional CKJ, a comparison was made between the biological activities of four soybean cultivars in their unfermented soybean (UFS) and CKJ states. Changes in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays, superoxide dismutase (SOD)-like activity, total phenolic compounds, total amino acids, and isoflavones were investigated. The levels of DPPH, ABTS, SOD-like activity, and total phenolic compounds increased in CKJ among all cultivars. The isoflavone aglycone and total amino acids showed the highest amount in CKJ prepared from soybean cultivar Aga 3. These results suggest that the improved antioxidant activity of CKJ in all cultivars might occur because of the higher levels of aglycones and total phenolic compounds achieved during fermentation. Moreover, CKJ prepared from soybean cultivar Aga 3 showed higher antioxidant activity than the other cultivars and so can be considered for the commercial production of functional foods in the future.

To investigate the physicochemical properties of unripe peach-Prunus persica cv. Mibaekdo (Mibaekdo) and Prunus persica cv. Nagasawa Hakuho (Nagasawa Hakuho) as an alternative to food supplement while Japanese apricot (Prunus mume cv. Backaha) (Backaha) was used as a control sample. The unripe fruits were analyzed for soluble solid ( ˚Brix), titratable acidity, pH, total polyphenol content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, amygdalin content, free amino acid content, organic acid content, free sugar content, and α-amylase activities. Total polyphenol content of unripe peach ranged between 137.27-151.64 µg/g whereas that of apricot was 160.73 µg/g. DPPH radical scavenging activities of Backaha was the highest (89.16%) followed by Mibaekdo (85.05%) and Nagasawa Hakuho (41.50%). The highest amount of oxalic acid (612.8 mg/100 g) was observed in Mibaekdo while that of Nagasawa Hakuho and Backaha were (184.6±18.1) and (334.8±16.1) mg/100 g, respectively. Amygdalin contents of Mibaekdo, Nagasawa Hakuho and Backaha were 486.61, 548.60 and 174.28 µg/g, respectively. The results suggest that the unripe fruit of peach has a significant biochemical potential of using as a food supplement with potential health benefit for human health.