Kuersetin Dan Kuersetin-3-O-Glukosida Dari Kulit Batang Sonneratia Alba (Lythraceae)

Two flavonoid compounds, quercetin (1) and quercetin-3-O-glucoside (2) have been isolated from the bark of Sonneratia alba (Lythraceae). Chemical structure of both compounds were determined on the basis of spectroscopic data and comparison with those spectra data previously reported. Compound 1 and 2 exhibited antibacterial activity against Gram-positive bacteria, Staphylococcus aureus and Streptococcus mutans with MIC values of 51.2; 48.8; 72.5; dan 100.7 µg/mL respectively.DOI :http://dx.doi.org/10.15408/jkv.v0i0.315

Effects of Temperature and Mobile Phase Condition on Chiral Recognition of Poly(l-phenylalanine) Chiral Stationary Phase

Characteristics of the chiral stationary phase with poly(l-phenylalanine) peptide selector, which was in α-helical state, was reported. Since environmental factors affect peptide conformation, the changes in enantioselectivity were examined depending on column temperature and mobile phase conditions (ionic strength, pH, mobile phase composition). Column temperature and pH drastically affected the enantioselectivity. Based on these changes, the relation between chiral recognition and secondary structure of the peptide selector was discussed. The column stability during sequential analysis under different separation conditions was also evaluated