Isolation and Biochemical and Molecular Identification of Lactobacillus Plantarum ‎Bacteria from Rhizosphere of Lenjan Rice

Introduction: Probiotics refers to a group of living microorganisms that have beneficial effects on host health. Lactobacilli are one of the most important probiotic bacteria. The stimulatory effects of the immune system, besides reduction of gastrointestinal infections and the risk of inflammation of intestines in humans and animals, are some of Lacobacillus benefits. The effect of rhizospher bacteria, like Lactobacillus, on production of plant hormones, dissolving plant nutrient, facilitates the absorption of nutrients (like nitrogen), and the reduction of plant diseases were reported. Isolation of Lactobacillus has been reported of various sources of dairy and non-dairy sources. The purpose of this study was to investigate the presence of  L. plantarum, one of most important probiotic bacteria, in rice rhizosphere, along with examination of the morphological, molecular, biochemical and probiotic properties of the isolated microorganisms. Materials and Methods: Sampling of rhizosphere rice variety was carried out in Lenjan (Lenjan, Isfahan) carried out. Dillutions of samples were transferred to MES medium. Biochemical test, as sugar fermentation and enzyme activity, performed on gram-positive isolate bacilli. The ability of bacteria to grow in presence of Bile salt, and different pH and temperatures was investigated. Antibiotic resistance of isolates was examined. Specific primers of L. plantarum was used for molecular identification. Results: Of 16 microorganisms, isolated from the rice's rhizosphere, there were 10 bacillus-shaped bacteria, which eight gram-positive isolates were oxidase and catalase negative (characteristic of Lactobacillus species). Sugar fermentation experiments identified six isolates with L. plantarum characteristics. Molecular experiments with the specific primers of L. plantarum confirmed the results. The bacteria grew very well (similar to control samples) in acidic medium at pH 3.5,  40ºC, and in presence of 0.3% bile. Resistance to seven of 12 antibiotics was detected. Discussion and conclusion: The present study showed that rhizosphere of rice is the natural source for isolationof L. plantarum

Growth Inhibitory Effect of Anthemis haussknechtii Root Extract, as a Source of Parthenolide, on Breast Cancer Cell Line

Parthenolide is major Sesquiterpene lactones present in Anthemis haussknechtii Boiss. & Reut. (feverfew). This compound has many effects on different disease such as migrain and cancer. Parthenolide was reported from Tanacetum parthenium (L.) Sch.Bip. but other plants of Asteraceae family could contain parthenolide. In this study parthenolide was extracted and identified with two methods, Fourier Transform Infra-Red Spectroscopy (FTIR) and High Performance Liquid Chromatography (HPLC). Breast cancer cell line, MDA-MB-231, was exposed to different concentrations of parthenolide for 24 hours.  Half maximal inhibitory concentration (IC50) was evaluated using Methylthiazol Tetrazolium (MTT) test. Based on results, 1000 µg/ml concentration is the minimum lethal dose that kills approximately 50% of cells after 24 hours. The results revealed that the A. haussknechtii parthenolide dramatically decreased survival of cancer cell line by inducing apoptosis. This is the first report of cytotoxicity effect of A. haussknechtii extract on breast cancer cell line

Evaluation of Antibacterial Activities of Some Medicinal Plants, Traditionally Used in Iran: Antibacterial activities of some medicinal plants

The aim of this study was to assess the antibacterial activities of some medicinal plants extracts traditionally used in Iran. Hydroalcoholic extracts obtained from different parts of five plants including Rosmarinus officinalis L. (rosemary), Syzygium aromaticum L. (Clove)., Arctium lappa L. (Burdock) , Coriandrum sativum, Myrtus communis with traditional medicinal use were examined for theirantibacterial activities against some gram-negative strains including Pseudomonas aeruginosa, Salmonella typhi, Proteus mirabilis, Klebsiella oxytoca and Shigella dysentriae. The disc diffusion method was applied to screen the antibacterial efficacy of the extracts. Gentamicin was used as control. This study showed that the extracts obtained from Syzygium aromaticum L., Arctium lappa L. and Myrtuscommunis had antibacterial activity against Proteus mirabilis. In addition, only the Myrtus communis extract had some inhibiting effect on the growth of Pseudomonas aeruginosa. The result of the current study revealed that some of the studied plants could be considered as potential source of antimicrobial agents and supports the traditional applications of a number of the tested plants as antibacterial reagents