Methyl gallate is a major component of Galla Rhois, as carvacrol is of oregano essential oils. Both have shown good antibacterial activity against intestinal bacteria. This study investigated the antibacterial activities of nalidixic acid in combination with methyl gallate and carvacrol against nalidixic acid resistant bacteria. The combined effect of nalidixic acid with methyl gallate and carvacrol was evaluated using the checkerboard method to obtain a fractional inhibitory concentration index. The results showed that the combinations of nalidixic acid + methyl gallate/carvacrol improved nalidixic acid resistant pathogenic bacteria inhibition with synergy or partial synergy activity. Thus, a strong bactericidal effect of the drug combinations was observed. In vitro data thus suggested that nalidixic acid combined with methyl gallate and carvacrol may be microbiologically beneficial, rather than antagonists.

Ecklonia cava is a brown alga (Laminariales, Phaeophyta) growing on the subtidal rocky shores of Korea. It has antioxidant, antidiarrhea, and anticoagulant effects. In this study, the antimicrobial activity of E. cava EtOH extract and its fractions (n-hexane, CH₂Cl₂, EtOAc, n-BuOH, and H₂O) were investigated against methicillin-resistant Staphylococcus aureus and Salmonella spp. The E. cava EtOAc fraction showed good antibacterial activity against all bacteria. Eckol isolated from E. cava EtOAc fraction showed antimicrobial activity against all the tested strains. The minimum inhibitory concentration of eckol against S. aureus strains ranged from 125 to 250 μg/mL and 125 to 250 μg/mL for Salmonella strains. The fraction inhibitory concentration index of eckol in combination with ampicillin ranged from 0.31 to 0.5, indicating remarkable synergism against S. aureus. However, against Salmonella gallinarum ATCC 9184 and Salmonella typhimurium, it ranges from 0.75 to 1.0. The combinations of eckol + ampicillin exhibited improved inhibition of S. aureus and Salmonella with synergy or additive effect. We suggest that eckol ingredients of the E. cava against S. aureus and Salmonella have antibacterial activity.

Increased health awareness among the public has highlighted the health benefits of dietary supplements including flavonoids. As flavonoids target several critical factors to exert a variety of biological effects, studies to identify their target-specific effects have been conducted. Herein, we discuss the basic structures of flavonoids and their anticancer activities in relation to the specific biological targets acted upon by these flavonoids. Flavonoids target several signaling pathways involved in apoptosis, cell cycle arrest, mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)/AKT kinase, and metastasis. Polo-like kinase 1 (PLK1) has been recognized as a valuable target in cancer treatment due to the prognostic implication of PLK1 in cancer patients and its clinical relevance between the overexpression of PLK1 and the reduced survival rates of several carcinoma patients. Recent studies suggest that several flavonoids, including genistein directly inhibit PLK1 inhibitory activity. Later, we focus on the anticancer effects of genistein through inhibition of PLK1.

Punica granatum is commonly used in Korea as a traditional medicine for the treatment of pathogenic bacteria. In this study, we investigated the in vitro and in vivo antimicrobial activity of P. granatum peel EtOH extract (PGPE) against 16 strains of Salmonella. The minimal inhibitory concentrations of PGPE were in the range of 62.5–1000 x03BCg mL^-1. In addition, the in vivo antibacterial activity of the PGPE extract was examined in a S. typhimurium infection mouse model. Mice were initially infected with S. typhimurium and then with PGPE. The extract was found to have significant effects on mortality and the numbers of viable S. typhimurium recovered from feces. Although clinical signs and histological damage were rarely observed in the treated mice, the untreated controls showed signs of lethargy and histological damage in the liver and spleen. Taken together, the results of this study indicate that PGPE has the potential to provide an effective treatment for salmonellosis.