Pathogenic microorganisms affecting plant health are a major and chronic threat to food production and ecosystem stability worldwide As agricultural production intensified over the past few decades, producers became more and more dependent on agrochemicals as a relatively reliable method of crop

Use of Plant Growth-Promoting Bacteria for Biocontrol of Plant Diseases: Principles, Mechanisms of Action, and Future Prospects

Anthocyanins and other flavonoids

Analytical separation and detection methods for flavonoids.

Comparative study on the antibacterial activity of phytochemical flavanones against methicillin-resistant Staphylococcus aureus

Differently substituted flavanones were isolated from Leguminosae and their antibacterial activity was comparatively studied against methicillin-resistant Staphylococcus aureus (MRSA). The minimum inhibitory concentrations (MICs) of phytochemical flavanones to clinical isolates of MRSA were determined by a serial agar dilution method. The structure-activity relationship has indicated that 2',4'- or 2',6'-dihydroxylation of the B ring and 5,7-dihydroxylation of the A ring in the flavanone structure are important for significant anti-MRSA activity and that substitution with a certain aliphatic group at the 6- or 8-position also enhances the activity. Among the thirteen flavanones tested, tetrahydroxyflavanones with these structural characteristics isolated from Sophora exigua and Echinosophora koreensis showed intensive activity to inhibit the growth of all MRSA strains at 3.13-6.25 micrograms/ml. The present hydroxyflavanones would be useful in the phytotherapeutic strategy against MRSA infections.

Comparative Study on the Antibacterial Activity of Phytochemical Flavanones against Methicillin-resistant Staphylococcus aureus.

Antimicrobial agents from Bletilla striata

Biphenanthrenes from Bletilla striata

Stilbenoids from Bletilla striata

Two antibiotic compounds, sarothralen A and sarothralen B, from Hypericum japonicum Thunb. ( Sarothra japonica Thunb.) have been isolated and their structures were elucidated on the basis of spectroscopic data. The compounds contain phloroglucinol and filicinic acid residues.

Masae Yamaki

Papers

Antimicrobial agents from Bletilla striata

Biphenanthrenes from Bletilla striata

Stilbenoids from Bletilla striata

Sarothralen A and B, new antibiotic compounds from Hypericum japonicum.

Blestrianol A, B and C, biphenanthrenes from Bletilla striata☆