مؤسسة عبد الحميد شومان > البحث العلمي > صندوق دعم البحث العلمي

الرجوع

Molecular Characterization of Local Streptomyces Isolates and Determination of Their Cytotoxicity against Breast Cancer

مجال مشروع البحث–الرئيسي: العلوم الطبية والصحية
مجال مشروع البحث–الثانوي: العلوم الصيدلانية
المؤسسة العلمية: جامعة البلقاء التطبيقية
المحافظة: السلط
قيمة الدعم: JD10553.28
سنة الدعم: 2011
حالة المشروع: منتهي مع النشر
البحث منشور: (1) Hawari, A., Obeidat, M., Abu-Romman, S., Odat, N., Haddad, M., & Al-Abbadi, A. (2017). Antimicrobial and insecticidal activities of n-butanol extracts from some streptomyces isolates. Research Journal of Microbiology, 12(4), 218-228. (2) Obeidat, M. (2017). Cytotoxicity of n-Butanol extracts of Streptomyces against human breast cancer cells. International Journal of Pharmacology, 13(8), 969-979.
ملخص عن مشروع البحث: 1. Background: Increasing antibiotic resistance and the appearance of multidrug-resistant pathogenic strains of bacteria and fungi are becoming a serious global problem. The use of biological insecticides instead of the chemical insecticides has been increased because of their safety, specificity and biodegradability. Objectives: The objectives of the study were to identify Streptomyces isolates screened from soil and to determine their antibacterial, antifungal and insecticidal activities. Materials and Methods: Streptomyces isolates collected from soils in various habitats of Jordan were cultured on Starch-Casein-Nitrate Agar (SCNA) medium and identified based on their morphological and cultural characteristics. Tryptone Soy Broth (TSB) cultures of isolates were extracted by n-butanol and screened for their antibacterial and antifungal activities using the agar-well diffusion method. Furthermore, the extracts were examined for their insecticidal activity against Drosophila melanogaster using conventional bioassay protocol. The LC50 values of extracts at 95% confidence interval were determined by probit analysis. Results: In total, 127 Streptomyces isolates were isolated from Jordanian soils with white aerial mycelia and rectus-flexous sporophores being dominant. It was found that the n-butanol extracts of 37 Streptomyces isolates prepared from cultures that were grown in TSB medium, which was considered as the most suitable medium in this study for the production of antimicrobial activity, exhibited antibacterial and/or antifungal activities on multidrug resistant microorganisms. Interestingly, it was observed that 11 isolates exhibited antibacterial activity on MRSA. It was also found that none of the isolates which displayed orange, red and yellow aerial mycelia produced antimicrobial activity. On the other hand, 19 isolates divided into seven color series exhibited insecticidal activity against D. melanogaster. The insecticidal activity of combined crudes of the most significantly toxic Streptomyces isolate S2 and Bacillus thuringiensis subsp. israelensis J63 was higher than that produced from either S2 or J63. Based on the interspacer region 16S-23S rRNA gene sequence analysis, the sequence alignment of the selected isolates had the greatest possible identity to Streptomyces and are grouped into two subclusters in the phylogenetic tree. Conclusion: Streptomyces cultures obtained from TSB medium have an increased and a promising antimicrobial activity against multidrug-resistant pathogens. Combined crudes of Streptomyces and B. thuringiensis produced competitive insecticidal activity. https://scialert.net/abstract/?doi=jm.2017.218.228 2. Background and Objectives: Breast cancer is the second most common cancer in the world and the most frequent cancer among women. This study was conducted to investigate the anticancer activities of n-butanol extracts prepared from Streptomyces isolated from soils in Jordan against breast cancer MCF7 cells. Materials and Methods: After isolation and identification of Streptomyces isolates by conventional methods, n-butanol extracts were prepared from Streptomyces cultures. Hemolytic activity of extracts was determined. The cytotoxic effect of non-hemolytic extracts on normal MCF10A cells was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) assay. The in vitro and in vivo selective cytotoxicity of extracts against breast cancer was estimated. The mechanism of action of extracts that exhibited in vivo cytotoxicity was determined. Isolates that gave in vivo cytotoxicity were identified by PCR amplification and sequencing. The IC50 values of extracts were determined by non-linear regression analysis. For tumor volume inhibition ratio, one-way ANOVA was applied for statistical evaluation of data and significant differences were considered significant at p<0.05. Results: The white aerial mycelia and the production of Rectus-Flexibilis (RF) sporophores as well as soluble pigments were the most common among Streptomyces isolates that screened from soil samples. The non-hemolytic n-butanol crude extracts of Streptomyces isolates (48 isolates) were screened for their cytotoxicity against normal breast MCF10A cells. Results indicated that out of the 23 non-toxic extracts on MCF10A cells, extracts of 9 isolates showed selective in vitro cytotoxicity against breast cancer MCF7 cells with IC50 values ranged from 0.68-1.64 mg mL–1. It was found that in vivo inhibition of breast cancer tumor in experimental animals was significantly increased, at α = 0.05, after treatment with extracts of 3 Streptomyces isolates (S7, S17 and S61). The DNA laddering (apoptosis feature) was observed in MCF7 cells treated with extracts of isolates S7 and S61. Analysis of 16S-23S rRNA gene sequence revealed that those 3 isolates have maximal identity to the genus Streptomyces. Conclusion: The result of the current study suggests that n-butanol extracts of 3 Streptomyces isolates have selective cytotoxicity against breast cancer MCF7 cells and 2 of the extracts induce apoptotic property in MCF7 cells. https://scialert.net/abstract/?doi=ijp.2017.969.979