Effect of Agitation and Aeration on Keratinase Production in Bioreactors Using Bioprocess Engineering Aspects.

Streptomyces sp. 2M21 was evaluated for keratinase production in bioreactors using chicken feathers. Firstly, optimization of bioengineering parameters (agitation and aeration rates) using Response Surface Methodology was carried out in 2 L bioreactors. Optimized conditions identified by the modified quadratic model were verified as 150 rpm and 1 vvm experimentally corresponding to 351 U/ml of keratinase activity. Moreover, scaling up sequentially to 20 L bioreactors was implemented using constant impeller tip speed and constant mass transfer coefficient as key scale-up parameters. The keratinase activity in 5, 10 and 20 L bioreactors showed similar results with the one of shake flasks (412 U/ml) and 2 L bioreactors (351 U/ml)with respect to the keratinase activity values of 336, 385 and 344 U/ml, respectively. The results suggest keratinase production by evaluating chicken feathers in commercial level. Furthermore, this study has potential to contribute industrial scale production of keratinase by Streptomyces sp. 2M21 using the proposed bioreactor conditions.

Inhibitory effects of rosemary extracts, carnosic acid and rosmarinic acid on the growth of various human cancer cell lines.

The leaves of Rosmarinus officinalis harvested from three different locations of Turkey were extracted by both methanolic and supercritical CO(2) extraction. Subsequently, six extracts and the active compounds, carnosic acid, and rosmarinic acid were applied to various human cancer cell lines including NCI-H82 (human, small cell lung, carcinoma), DU-145 (human, prostate, carcinoma), Hep-3B (human, black, liver, carcinoma, hepatocellular), K-562 (human chronic myeloid leukemia), MCF-7 (human, breast, adenocarcinoma), PC-3 (human, prostate, adenocarcinoma) and MDA-MB-231 (human, breast, adenocarcinoma) by MTT assay. Supercritical CO(2) extracts had superior antiproliferative effect compared to the soxhlet extracts. Although the extracts exhibited various cytotoxic effects against different cell lines, comparatively low IC(50) values ranging between 12.50 and 47.55 microg/ml were attained against K-562, being the most sensitive cell line. Moreover, carnosic acid caused the lowest cell viability with values ranging from 13 to 30 % at a concentration of 19 muM after 48 h of treatments, resulting in superior antiproliferative effect. Rosemary extract is a potential candidate to be included in the anti-cancer diet with pre-determined doses avoiding toxicity.

Determination of phenolic content and antioxidant activity of extracts obtained from Rosmarinus officinalis' calli.

Rosmarinus officinalis is widely found in the lands of Aegean and Mediterranean regions of Turkey. Stem explants of very young shoots were cultured in both woody plant medium (WPM) and Murashige and Skoog (MS) media supplemented with 7g/L agar, 30g/L sucrose, and 1 and 3mg/L naphthaleneacetic acid (NAA) for callus initiation. Induced calli were subcultured 4 times with intervals of 7-10 days. MS medium supplemented with 1mg/L NAA proved to be the best medium for the production of callus (65.0%) among the samples tested. The lyophilized calli were subjected to solvent extraction. Active constituents of 8 calli extracts were analyzed by HPLC, and rosmarinic acid (RA) was determined to be the primary compound. Calli cultivated in WPM supplemented with 1mg/L NAA and extracted at 50 degrees C, yielded the highest amount of RA (34.4mg/g dry weight). Moreover, antioxidant activity of calli extracts was determined using a number of in vitro assays, including total phenol assay, DPPH radical scavenging activity (RSA), and trolox equivalent antioxidant capacity (TEAC). On the basis of the current findings, we conclude that WPM supplemented with 1mg/L NAA yields higher phenolic content as well as higher antioxidant activity.