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    Antimicrobial activities of the essential oils of four Salvia species from Turkey
    (Academic Journals, 2010) Karatas, Hakan; Ertekin, Selcuk
    In the present study, antibacterial and antifungal activities of essential oils of four Salvia species against five bacteria and one fungus were evaluated at concentrations of 1/10, 1/20 and 1/30 and incubated for 24 h. Aqueous and hexane extracts of each plant were tested for their antibacterial and antifungal activity by using agar disc diffusion method. The result indicated that all essential oils exhibit antibacterial activity against Bacillus subtilis, Escherichia coli and Staphylococcus aureus. In addition, essential oils of Salvia multicaulis exhibit the antibacterial activity against Pseudomonas aeruginosa. Essential oils of Salvia syriaca exhibit antibacterial and antifungal activities against all micro-organisms.
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    Chemical Composition, Antimicrobial and Antioxidant Activities of Hyssop (Hyssopus officinalis L ) Essential Oil
    (Univ Agr Sci & Veterinary Med Cluj-Napoca, 2010) Kizil, Suleyman; Hasimi, Nesrin; Tolan, Veysel; Kilinc, Ersin; Karatas, Hakan
    The essential oil of hyssop is widely used in food pharmaceutical and cosmetic industries throughout the world Therefore, it is very important to know the chemical characteristics of the oil for economic use and enhanced performance of the end products This study was carried out to determine antimicrobial and antioxidant activities of the essential oil of Hyssopus officinalis (L) (Lamiaceae) collected from wild in the Southeast Anatolian Turkey Chemical compositions of hydrodistilled essential oils obtained from hyssop leaves were analyzed by gas chromatography mass spectrometry (GC MS) For antimicrobial activity disc diffusion tests were carried out on Escherichia coli line ATCC25922 Pseudomonas aeroginosa line ATCC27853 Staphylococcus aureus line 25923 Staphylococcus pyogenes line ATCC19615 and Candida albicans line ATCC10231 and the antioxidant activity was determined by using the diphenylpicrylhydrazyl (DPPH) radical scavenging method It was determined that hyssop essential oil contained isopinocamphone (5727%) () beta pinene (7 23%) () telpinen 4-ol (7 13%) pinocaivone (649%) carvacrol (3 02%) p cymene (2 81%) and myrtenal (2 32%) as major components As shown by treatments with 5 and 10 mu of oil which exhibited strong antimicrobial activity against S pyogenes S aureus C albicans and E colt but not against P aeruginosa The antioxidant activity of H officinalis essential oil was lower compared to butylated hydroxytoluene (BHT) and ascorbic acid These results demonstrated that hyssop essential oil has relatively low antioxidant activity and good antimicrobial activity against some test organisms
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    Optimization and enhanced production of ?-amylase and protease by a newly isolated Bacillus licheniformis ZB-05 under solid-state fermentation
    (Springer, 2013) Karatas, Hakan; Uyar, Fikret; Tolan, Veysel; Baysal, Zubeyde
    Eight different agro-residues were tested for alpha-amylase and protease production by using Bacillus licheniformis ZB-05. Among them, rice husk (RH) was proved as the best substrate for two enzymes (alpha-amylase 443 U/g and protease 469,000 U/g). Maximum enzyme production was observed to be 30 % initial moisture, with a growth period of 36 h in 20 and 30 % inoculum volumes for alpha-amylase and protease, respectively. The best enzyme recovery from solid mass was obtained when extracted with tap water. Among the tested various nitrogen sources, 1 % ammonium sulphate followed by 2 % Bacto liver, 2 % ammonium sulphate and 1 % Bacto casaminoacid served as the best inorganic and organic nitrogen sources for alpha-amylase and protease production, respectively. As additional carbon sources, 2 % soluble starch enhanced alpha-amylase production, while 1 % maltose enhanced protease production.