Investigation of Pomegranate (Punica granatum L.) Flowers' Antioxidant Properties and Antibacterial Activities against Different Staphylococcus Species Associated with Bovine Mastitis.

Mastitis is one of the most considerable and costly diseases for dairy herds, and Staphylococcus spp. is known to be the main causative agent. Although antibiotics are widely used in the treatment of mastitis, this can cause both antibiotic residues in milk and the risk of antibiotic resistance occurrence in bacteria. Thus, in recent years, researchers have focused on alternative treatments for this disease and plants extracts are investigated for this purpose. Pomegranate is widely used as a dye, ornament, and medicinal plants in the industry, and the species has a particularly high economic value in Turkey. This study aims to investigate in vitro the antioxidant and antibacterial properties of the pomegranate flower's extracts against different Staphylococcus species associated with bovine mastitis. To this aim, pomegranate flowers were collected from different regions in Turkey and extracts were prepared with three different solvents (methanol, ethanol, and water). The retention factor values of the ethanol extract were determined by thin-layer chromatography. The antibacterial activity tests were carried out via the disk diffusion method. In addition, the extracts were tested against the stable DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radicals for antioxidant activity. Four retention factors (0.79, 0.67, 0.58, and 0.33 points) were found for the ethanol extract. The methanol extract showed the highest inhibition zones against coagulase-negative Staphylococcus-37 (CNS-37) and S. aureus-18. The lowest MIC was 6500 µg/mL. The highest antioxidant activity was observed in methanol extracts. As a result, the extracts of pomegranate flowers showed a high antioxidant and antibacterial potential against the examined mastitis pathogens.

THE BIOLOGICAL ACTIVITIES OF MOLTKIA AUREA BOISS., AN ENDEMIC SPECIES TO TURKEY.

BACKGROUND: Staphylococcus aureus is the direct reason of mastitis. Mastitis is a disease characterized by pathological changes in mammary glands as well as physical, chemical, bacteriological changes in milk. This disease causes loses in milk yield and quality. In recent years, it is reported that mastitis pathogens have developed a resistance to antibiotics as a natural consequence of widespread use of it. Today's researches are focused on discovering and using new antibiotics against bacteria. The aim of this paper is to examine the antibacterial properties of Moltkia aurea Boiss.][o] (an endemic species to Turkey), and its other biological activities. MATERIALS AND METHODS: All of the extracts were tested by disc diffusion assay in order to screen antibacterial activity. MIC values were evaluated as antibacterial activities of plant extracts. The non-enzymatic antioxidative activities including DPPH radical scavenging effects were studied in vitro. RESULTS AND CONCLUSIONS: Results shown that the extracts had strong antibacterial effects on three bacteria (S. aureus- 17, S. aureus-18 and CNS-37) and the range of inhibition zone was 4-6mm. This three bacteria screened the lowest sensitivity to 65000 µg /mL concentration. Besides, the extracts were tested for non-enzymatic antioxidant activities. As a result, the methanol extract of the flower displayed a strong antioxidant activity. The various extracts of Moltkia aurea have different antibacterial and antioxidant properties.

THE BIOLOGICAL ACTIVITIES OF HYPERICUM PERFORATUM L.

BACKGROUND: Mastitis reduces milk yield and alters milk composition. Antibiotics are widely used in the treatment of the disease. However, this widespread use of antibiotics causes both antibiotic residues in milks and antibiotic resistance developed in bacteria. Today's researches are focused on discovering and using new antibiotics against bacteria. OBJECTIVE: The aim of this work was to discover the antibacterial effects of Hypericum perforatum L. extracts against mastitis pathogens, and its other biological activities. MATERIAL AND METHODS: Kirby-Bauer assay was applied to the extracts. The other antibacterial activity was MIC for plant extracts. The non-enzymatic antioxidant activity was found using 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH). RESULTS: The extract was showed maximum inhibition zone against two bacteria (Coagulase-negative Staphylococci-33 and 37; CNS 33 and 37), and the zone was 17 mm. A bacterium (CNS - 22) showed the lowest sensitivity to 812.5 µg/mL concentration. In addition, the extract was tried against the stable DPPH for antioxidant activity. As a result, the extract showed a strength antioxidant activity. Trolox equivalent is 0.83 mM. CONCLUSION: The extract of Hypericum perforatum have antibacterial, antioxidant and antimutagenic potentials.

New Lipase for Biodiesel Production: Partial Purification and Characterization of LipSB 25-4.

The lipolytic activities of 300 Streptomyces isolates were determined in Tributyrin and Rhodamine-B Agar. Lipase activities were also measured with p-nitrophenyl palmitate (p-NPP) as a substrate. The strain of Streptomyces bambergiensis OC 25-4 used in this study was selected among 300 strains of Streptomyces from MUCC as the best lipase producer. The incubation conditions were optimized and the inoculum amount, incubation period, effect of carbon and nitrogen sources, and rates of MgSO4 and CaCO3 were investigated. LipSB 25-4 (the lipase produced by S. bambergiensis OC 25-4 strain) was partially purified with ammonium sulphate precipitation, dialysis, and gel filtration chromatography 2.73-fold and with 92.12 U/mg specific activity. The optimal pH and temperature for LipSB 25-4 were determined as 8.0 and 50°C, respectively. The lipase has high stability in all pH and temperature values used in this study. While LipSB 25-4 was slightly activated in the presence of ß-mercaptoethanol, it was slightly reduced by PMSF. The enzyme conserved approximately 75% of its activity at the end of 60 h, in the presence of methanol and ethanol. Since LipSB 25-4 displays high activity in the thermophilic conditions and stability in the presence of organic solvents, this lipase can catalyse the biodiesel production from olive oil by the transesterification reactions.