Investigation of antimicrobial and anticancer activities of Althaea officinalis L. extracts obtained after uv application to callus cultures

Althaea officinalis L., a plant of the Malvaceae family, is widely used in alternative medicine. The aim of this study is to cultivate the A. officinalis plant in vitro, create an appropriate callus regeneration protocol and to investigate the antimicrobial and anticancer activities of methanol and ethyl acetate extracts of calli after UV-C application, using different parts of the plant as an explant source. It is very important to ensure the surface sterilization of the plant material in in vitro studies. For the surface sterilization of the seeds commercial bleach is used for 10, 15, 20, 25, 30 minutes. We found that the most effective sterilization is obtained soaking the seeds in 100% commercial bleach for 30 minutes. We observed that the sterilized seeds have difficulties of germination, so we aimed to develop a suitable germination protocol by using different nutrient media and different solidifying agents. MS + plant agar, MS + gelrite, Gamborg-B5 + plant agar and Gamborg-B5 + gelrite were used as germination media. The most effective germination was seen in the nutrient medium prepared using 28% MS + gelrite. Leaf, petiole and root parts of Althaea officinalis plants germinated in sterile environment were used as explant sources. Explants were cultured in MS medium containing different concentrations of 2,4-D (1.2 mg/l) and BAP (0,25, 0,50, 0,75 mg/l). The most effective callus growth rate and callus weight is observed in petiole explants MS nutrient medium containing 1 mg/l 2,4-D + 0,25 mg/l BAP at a rate of 100% with the weight 516,24±0,48 mg. The most inefficient explant in terms of callus development was the root. Calli obtained from leaf and petiole explants were exposed to UV-C treatment for 15 minutes from a distance of 15 cm. After the UV-C application, the calli were kept in the climate cabinet for 48 hours under suitable conditions.Extractions of calli were carried out using methanol and ethyl acetate solutions. 1 mg/ml, 5 mg/ml and 10 mg/ml solutions of methanol and ethyl acetate extracts were prepared and their antimicrobial activity on bacteria was investigated using the disc diffusion method for 7 different gram-positive (Bacillus subtilis ATCC 6337, Brevibacillus brevis, Bacillus megaterium DSM 32, Bacillus subtilis IM 622, Bacillus cereus EMC 19, Staphylococcus aureus 6538 P, Listeria monocytogenes NCTC 5348) and 9 different gram-negative (Salmonella typhimurium NRRLE 4413, Pseudomonas fluorescens, Enterobacter aerogenes CCM 2531, Klebsiella pneumoniae EMCS, Escherichia coli ATCC 25922, Proteus vulgaris FMC II, Pseudomonas aeruginosa DSM 50070, Proteus vulgaris, Salmonella enterica ATCC 13311 ) bacteria. None of the three extract concentrations used had any antimicrobial activities.The anticancer activities of the extracts on SH-SY5Y human neuroblastoma cells were studied using the WST-1 viability kit. The 1000, 500, 250, 125, 62,5 μg/ml concentrations of ethyl acetate extracts of leaf and petiole calli have anticancer activity. The methanol extracts of leaf and petiole calli have anticancer activity at all concentrations (1000, 500, 250, 125, 62,5, 31,25, 15,625, 7,8125 μg/ml). Keywords: Althaea officinalis L., callus, extraction, antimicrobial activity, anticancer act.