• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.4
• /
• pp.350-359
• /
• 1993

The effect of gibberellic acid ($GA_3) and abscisic acid (ABA) on KCl-enhanced proteolysis of senescing leaves of rice(Oryza sativa L. cv. Chilsung) was studied. Emphasis was given to their effects on KCI-enhanced efflux of amino acids and proteinase activity. When treated singly, $GA_3 affected leaf proteolysis little, while ABA increased proteolysis, the rate of amino acid efflux, and ribulose -1,5 -bisphosphate carboxylase / oxygenase (Rubisco)-degrading endoproteinase activity. An additive increase in all three parameters mentioned above was observed when leaves were treated with ABA and KCl. No such an additive effect was found when $GA_3 was treated with KCl. Both $GA_3 and ABA helped to alleviate the KCI-suppressed activity of Rubisco-degrading exoproteinases. The additive increase in proteolysis of rice leaves in the presence of both ABA and KCl could thus be ascribed to a further increase in the efflux of protein hydrolyzates and Rubisco-degrading endoproteinase activity. An increase in proteolysis was accompanied by a decrease in water absorption, and the combined treatment of ABA with KCl resulted in a further reduction of water absorption.

• Food Science and Preservation
• /
• v.31 no.2
• /
• pp.287-297
• /
• 2024

It was confirmed that complex fermentation (CF) was more efficient than single-strain fermentations in inducing changes in the contents of phenolic compounds of Maclura tricuspidate and Pyrus Montana Nakai. A mixture of Maclura tricuspidata, Pyrus montana Nakai, Platycodon grandiflorum and Codonopsis lanceolata were fermented in CF using Aspergillus shirousamii (koji), yeast, and lactic acid bacteria (LAB) for 24 days, and the pH, °Brix, total acidity, anti-oxidant activity, polyphenol content, nitric oxide (NO), and Western blotting of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2), and tumor necrosis factor-𝛼 (TNF-𝛼) of the sample were determined. There was no significant change in pH and total acidity. °Brix significantly decreased from day 6 onwards. HPLC confirmed that the concentrations of chlorogenic acid, 4-hydrobenzoic acid, vanillic acid, and caffeic acid significantly increased from day 18 during the fermentation. Additionally, DPPH, ABTS radical scavenging activity, total phenol, and total flavonoid were confirmed to be increased until 18 days. NO was significantly inhibited from day 6, along with significant inhibition of iNOS, COX-2, and TNF-a. In conclusion, this study confirmed that CF of low-use (or underutilized) wild vegetables enhances phenolic compounds. It effectively suppresses NO, iNOS, COX-2, and TNF-𝛼, markers of inflammation-related pathogenesis. Altogether, our results suggest that CF of the above plants has a potential anti-inflammatory effect.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.3
• /
• pp.369-377
• /
• 2013

In order to increase the utilization of sweet potato leaves and stalks as much as roots, it is necessary to study their beneficial potential. In this study, the antioxidant, antiallergic and anti-inflammatory effects of sweet potato leaves and stalks were evaluated by measuring total polyphenol and flavonoid contents, DPPH radical scavenging effects, the reducing power and inhibition effects on xanthine oxidase (XO), 5-lipoxygenase (LOX), and cyclo-oxygenase (COX)-2 activities. Blanched sweet potato leaves (SL), raw whole purple stalks (ST) and peeled stalks (PST) were freeze-dried and extracted with 95% ethanol. Total polyphenol content was highest in SL (11.03 mg/g), followed by ST (0.87 mg/g), and PST (0.37 mg/g). Total flavonoid content was highest for SL (9.01 mg/g), followed by ST (0.50 mg/g) and PST (0.25 mg/g). The $IC_{50}$ for DPPH radical scavenging effects was highest for SL ($43.6{\mu}g/mL$), followed by ST ($308.4{\mu}g/mL$) and PST ($1,631.3{\mu}g/mL$). The reducing power was highest for SL ($59.72{\mu}g$ ascorbic acid eq./mL), followed by ST ($12.56{\mu}g$ ascorbic acid eq./mL) and PST ($2.18{\mu}g$ ascorbic acid eq./mL) with $1,000{\mu}g/mL$ of ethanol extract. The inhibition rate on XO activity was highest for SL (13.06%), followed by ST (5.05%) and PST (0.0%) at $250{\mu}g/mL$ extract treatment. The inhibition rate on COX-2 activity was highest for SL (55.34%), followed by ST (2.18%) and PST (0.0%) at $250{\mu}g/mL$ extract treatment. The inhibition rate on 5-LOX activity was highest for SL (91.16%), followed by ST (33.38%) and PST (14.93%) at $50{\mu}g/mL$ treatment. Taken together, sweet potato leaves showed high antioxidative, anti-allergic and anti-inflammatory activities, especially with very strong inhibition effects on 5-LOX activity. These beneficial effects of sweet potato leaves might be mainly caused by the high content of polyphenols and flavonoids.