---

Background&Objective: Probiotics have been defined as live microorganisms that confer a health effect on the host when consumed in adequate amounts.Lactic bacteria play an important role in production and maintenance of the fermented and probiotic products.The aim of this study was to determine the efficacy of lactic bacteria, which isolated from yoghurt against Gastrointestinal pathogenic microorganisms in the Golestan province in North of Iran. Materials&Methods: In this descriptive study we used 96 strains which belong to 12 species of Lactobacillus and 5 species of Lactococcus ,that isolated from home made yoghurt, and their antimicrobial effect on 7 species of important intestinal pathogenic microorganisms were examined.After growing the Lactic bacteria in broth media centrifuged and filtred the suspension and used the supernatant for study.The effect of supernatant against intestinal pathogenic microorganisms were assessed by Disc diffusion and pour in well method and each test were repeated 3 times and mean inhibition zone were recorded. Results: Lactobacillus casei and Lactococcus lactis showed better effect than other strains.The maximum light zone diameter was 18 milimeter. Maximum and minimum inhibitiry effect has seen in Yersinia enterocolitica and Bacillus cereus. Conclusion: Both Lactobacillus and Lactococcus strains had a proper inhibitory effect on the intestinal pathogenic bacteria but Lactobacillus strains that present in yoghurt showed better effect. This inhibitory effect was more obvious on the Yersinia enterocolitica.

---

Background&Objective: Staphylococcus aurues is on important cause of community and hospital- aquired infections. Caused by methicillin or oxacillin- resistant s.aureus (MRSA) are mainly nosocomial and are increasingly from many countries word wide. Many attempt have been made by the reasearchers to find new compounds as a subsitute for this antibiotics. The aim of this study was to investigate the antimicrobial activity of alcoholic extracts of 20 medical plants species of Golestan provience on clinical and standard strains of MRSA and MSSA and comprative and detect the best medical plant. Materials&Methods: In this study the compunds of the plant were extracted by percolation method and the effect of ethanolic extract of 20 Iranian medical plants against methicillin resistant and methicillin sensitve strains were assessed by disc diffusion method and each test were repeated 3 times and mean inhibition zone were recorded and then, the minimum inhibitory concentration (MIC) of the extracts, that show good inhibition zone in disc diffusion method, was determined by the micro broth dilution method. Results: The results of antibacterial activity of the ethanolic extracts of 20 plants revealed that, the ethamlic extracts of 8 plants have the best effect on strains and the maximum mean inhibition zone was 22.4 mm and the lowest MIC of plants was 0.01 mg/ml. Conclusion: The result of this study indicate that, ethanolic extract of Eucalyptus. Global, Peganum.hermla, Punica.granatum, Berberis.vulgaris, Ttamarixaphylla, Nnigella.sativa, Hypericum.perforatum AND, Artemisia. Herbaalba have the best antibacterial effect against MRSA andMSSA. The result obtained from these plants might be considered sufficent for further study.

---

Background & Objective: There is an increasing interests in substitution of natural products for synthetic chemicals in drugs and foodstuff. Reports of antibiotic resistant bacteria and side effects of chemical food preservatives suspected to be carcinogenic have drawn attention towards application of herbal and natural substances. Towards this end, edible plants are more safe and therefor have priority for investigation. In this study, antibacterial activities of six medicinal plants including Thymus (T.) eriocalyx and T. persicus, Allium (A.) haementhaides, Fumaria (F.) parviflora Lam, Buxus (B.) hyrecana pojark, and Tragopon (Tr.) carcifolus Lorestan province in Iran were examined. Materials & Methods: In this study, flowers and leaves from T.persicus, T. eriocalyx, and leaves from other plants were collected from Zagros highlands, dried and soaked in hexan for 48. The solvent was separated then evaporated under reduced pressure. The concentrated extracts were shaken and foze at -10°C. Then it was centrifuged and the solvent was evaporated. The extracts were finally resuspended in sterile PBS containing DMSO. Antibacterial activities were examined by disk diffusion and broth microdillution technique , using standard (ATCC) gram positive and negative bacteria and standard (Muller Hinton agar and broth or Isosensitest agar) media in order to determine Minimum Inhibitory (MIC) or Bactericidal (MBC) concentration. Results: Strong antibacterial activities were observed against both gram positive and negative bacteria including E.coli, S. aureous and P. aeroginosa by T.eriocalyx and F. parviflora. Also B. hyrecana pojark showed antibacterial activity against S. aureus at a concentration of MIC=320 µg/ml and MBC=80 µg/ml. Conclusion: This study showed that T.eriocalyx, F. parviflora and B. hyrecana pojark have antibacterial effects in vitro. Therefore it is suggested the application of these extract in medicine and food industings could be helpful.

---

Background and Objective: Probiotics are beneficial organisms therapeutic within microbial flora. Shigella, Escherichia coli and Salmonella are the most common cause of intestinal infectious diseases that lead to morbidity and mortality in infant and children worldwide. The aim of this study was to evaluate anti-microbial activity of Lactobacillus acidophillus and Lactobacillus ruteri against entero-pathoges by in vitro and in vivo methods. Methods: In this experimental study, the therapeutic effect of the lactobacillus acidophilus ATCC 4356 and ruteri ATCC 23272 against Shigella sonnei ATCC 9290, Escherichia coli ATCC 25922 and Salmonella enterica BAA-708 were evaluated by in vitro (spot agar) and in vivo (BALB/c mice) methods. Weight improvment and survival rate in mice were recorded. Results: Lactobacillus acidophillus and ruteri had protective and therapeutic effect against diarrhea caused by pathogenic bacteria. Probiotics reduced the weight, colonization of pathogens and increased the survival rate of animals (P<0.05). Conclusion: Lactobacillus acidophillus and ruteri has anti-microbial activity and their consumption can be effective in the prevention and also the treatment of intestinal disease.

---

Background and Objective: Nowadays, microorganisms have high resistance to antibiotics due to indiscriminate and unnecessary consumption. Treatment of infections caused by resistant bacteria has become difficult and expensive. Galls wild rose created by wasp's species Diplolepis mayri. This study was done to evaluate antibacterial activity of methanol, acetone and aqueous extracts of Wild Rose gall against Staphylococcus aureus and Enterococcus faecalis.
Methods: In this experimental laboratory study, the methanol, acetone and aqueous extracts of wild rose galls in 15.6, 31.3, 62.5, 125, 250 and 500 mg/dl were prepared by Soxhlet apparatus. Antibacterial activity of extracts was determined using well diffusion. MIC and MBC were determined by microdilution method. The active compounds of gall were evaluated by GC-MS.
Results: The inhibition zone of 500 mg/ml methanol, acetone and aqueous extracts of wild rose gall were 27.3, 26.7 and 20.0, respectively. The inhibition zone of wild rose gall was similar to imipenem (antibiotics). The extract concentration was related with antibacterial activity. The gall rose methanol extract showed the highest antibacterial effect. The MIC and MBC of methanol extract against Staphylococcus aureus and Enterococcus faecalis was 62.5, 31.3 mg/ml, respectively.
Conclusion: This study showed that aqueous, methanol and acetone extracts of wild rose galls have strong antibacterial activity.

---

Background and Objective: Curcumin is a combination of active polyphenol from the Curcuma Langa plant, which has extensive biological activities including effects anti-inflammatory, anti-bacterial and cytotoxic markers for multiple cancer cells. Berberine is an alkaloied isokinolin that is present in berberine and suppresses the growth of many tumor cells. This study was designed to determine the antibacterial effect of berberine and indium curcumin and indium diastile curcumin complexes against E-coli and Bacillus pumilus and comparison of their cytotoxicity on the cell lines of the bladder and stomach cancer cells.
Methods: In this descriptive-analytic study, antimicrobial activity and cytotoxicity effect of berberine and indium curcumin and indium diastile curcumin complexes was investigated by MTT and dilution test method respectively. E-coli [BL21 (DE 3)], Bacillus pumilus (PTCC 1529), cell lines of bladder (5637) and stomach (AGS) were evaluated.
Results: The minimum inhibitory concentration (MIC) of berberin for E-coli was determined 5 mM. At 100 micromolar concentration of berberine approximately 100% of the bladder cancer cells have disappeared. Cytotoxic effect of curcumin complexes on two bladder and stomach cancer cell lines showed that both complexes have different inhibitory effects on cell line life. Cytotoxicity of 20μM indium curcumin and indium diastile curcumin complexes for bladder cancer cells were 58% and 55%, respectively, and for stomach cancer cells were 61% and 34 %, respectively. Antibacterial activity of complexes against Bacillus pumilus and E-coli showed that none of the complexes has antimicrobial effect against Bacillus Pamilus, but both complexes inhibited the growth of E-coli bacteria. The bacteria population in the presence of indium curcumin and indium diastile curcumin complexes was reduced to 40% and 24%, respectively.
Conclusion: This study indicated that indium complexes of curcumin and diacetyl curcumin have a potential for anticancer and antibacterial therapy. Furthermore, berberine as an alkaloid has anticancer and antibacterial activity.

---

Background and Objective: Nosocomial infection is a major challenge in health care system. In fact, it is regarded as one of the risk factors in hospitalized patients. The aim of this study was to determine the antibacterial effect of silver nanoparticles (AgNPs) nursing gowns on geram – positive bacterial.
Methods: This descriptive and analytical study was done on 200 nurses gowns were surveyed in two hospitals of Sirjan city in Kerman Province cenral area of Iran. At first, the antimicrobial activity of silver nano fabrics on Staphylococcus aureus bacteria was confirmed by examining the optical density OD (0.325) medium. Sampling was gathered into the two modes, before using nano gowns and after using nano gowns by using wet sterile swabs. The samples collected were cultured and the formations of colonies were examined and biochemical tests were used to identify isolated bacterial.
Results: The most commonly isolated gram- positive bacterial from normal gowns were Staphylococcus epidermidis (43%) and the lowest pathogen was Streptococcus (1%). In these hospitals, after using nano silver gowns, the amount of microbial load on the clothes were determind zero.
Conclusion: This study showed that gram- positive bacterials of nursing gowns after contact with silver nanoparticles were eliminated.

---

Background and Objective: The emergence of Gram-positive and Gram-negative bacteria resistant to antibiotics is a crisis worldwide. In this study, the antibacterial effect of zinc oxide nanoparticles was evaluated on standard and food isolated strains of Salmonella enteritidis and Bacillus cereus.
Methods: This descriptive laboratory study, zinc oxide nanoparticles were prepared on zeolite materials, and zinc level was determined using XRF. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ZnO nanoparticles were determined using disc diffusion method.
Results: MIC value for all tested bacteria was 4 mg/ml and MBC values of standard and isolated strains of Salmonella enteritidis were 16 and 8 mg/ml, respectively, and for standard and isolated strains of Bacillus cereus was calculated in the range of 16 mg/ml.
Conclusion: Zinc oxide nanoparticles can inhibit Salmonella enteritidis and Bacillus cereus strains and may have a potential for its replacement with current preservatives to prevent food spoilage in industry.