Ferda Candan

Antioxidant and antimicrobial activity of the essential oil and methanol extracts of Achillea millefolium subsp. millefolium Afan. (Asteraceae)

The in vitro antimicrobial and antioxidant activities of the essential oil and methanol extracts of Achillea millefolium subsp. millefolium Afan. (Asteraceae) were investigated. GC-MS analysis of the essential oil resulted in the identification of 36 compounds constituting 90.8% of the total oil. Eucalyptol, camphor, alpha-terpineol, beta-pinene, and borneol were the principal components comprising 60.7% of the oil. The oil strongly reduced the diphenylpicrylhydrazyl radical (IC(50)=1.56 micro g/ml) and exhibited hydroxyl radical scavenging effect in the Fe(3+)-EDTA-H(2)O(2) deoxyribose system (IC(50)=2.7 micro g/ml). It also inhibited the nonenzymatic lipid peroxidation of rat liver homogenate (IC(50)=13.5 micro g/ml). The polar phase of the extract showed antioxidant activity. The oil showed antimicrobial activity against Streptococcus pneumoniae, Clostridium perfringens, Candida albicans, Mycobacterium smegmatis, Acinetobacter lwoffii and Candida krusei while water-insoluble parts of the methanolic extracts exhibited slight or no activity. This study confirms that the essential oil of Achillea millefolium possesses antioxidant and antimicrobial properties in vitro.

ANTIMICROBIAL AND ANTIOXIDATIVE ACTIVITIES OF THE ESSENTIAL OILS AND METHANOL EXTRACTS OF SALVIA CRYPTANTHA (MONTBRET ET AUCHER EX BENTH.) AND SALVIA MULTICAULIS (VAHL)

Abstract The essential oils and methanolic extracts of Salvia cryptantha and Salvia multicaulis were examined for their potential antimicrobial and radical scavenging activities. No, or slight, activity was observed when the polar and non-polar subfractions of the extracts were tested, whereas essential oils exhibited antimicrobial activity. The essential oils isolated from S. cryptantha and S. multicaulis were analysed by GC–MS and 53 and 47 constituents were identified, respectively. Antioxidant activities of the polar subfraction and the essential oil were examined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical-scavenging and lipid peroxidation assays. The essential oils, in particular, and the non-polar subfractions of methanol extracts, showed antioxidant activity. In conclusion, the results indicate that the oils of S. cryptantha and S. multicaulis have the capacity to scavenge free radicals and to inhibit the growth of pathogenic microorganisms. Therefore they could be suitable for using as antimicrobial and antioxidative agents in the food industry.

Concanavalin a Immobilized Monosize and Magnetic Poly(glycidyl Methacrylate) Beads for Use in Yeast Invertase Adsorption

Concanavalin A (Con A) immobilized monosize and magnetic poly(glycidyl methacrylate)[m-poly(GMA)] beads were investigated for specific adsorption of yeast invertase from aqueous solutions. m-Poly(GMA) beads (1.6 μ m in diameter) were prepared by dispersion polymerization in the presence of Fe3O4 nanopowder. The epoxy groups of m-poly(GMA) beads were opened by base catalyses. Then, Con A was immobilized by covalent binding onto the beads. Con A immobilization amount was 12.5 mg/g. The invertase adsorption capacity of the m-poly(GMA)/Con A beads was 111 mg/g. The maximum invertase adsorption on the m-poly(GMA)/Con A beads was observed at pH 5.5. The optimum activity for both free and adsorbed invertase was observed at 50°C. Vmax values were determined as 330 U/mg and 292 U/mg enzyme, for free and adsorbed invertase, respectively. KM values were found to be the same for free and adsorbed invertase (20 mM). Adsorption of invertase via Con A improved the pH stability of invertase. Thermal stability also increased with adsorption. The adsorbed enzyme activity was found to be quite stable in repeated experiments.