Studies on Antimicrobial Properties of Vegetable, Fruit & Spice ...

<strong>Studies</strong> on….Suvro Saha et.al.pieces. In case of coconut and stone apple the shells were neatly shaven. Then these peels and shellswere set aside for drying in sunlight for 24 hours and shifted to an hot air oven at 40 0 CMicrobial Strains & Culture Preparation:Bacterial Strains used: Staphylococcus aureus, Proteus vulgaris, Lactococcus lactis, Bacillussubtilis, Escherichia coli, Klebsiella pneumonia.Fungal strains used: Sporotrichum pruinosum, Candida albicans and Aspergillus niger.The bacterial cultures were maintained on nutrient agar media (pH-7.0). They were sub-culturedweekly and subsequently stored at 4 0 C. The fungal cultures were maintained on Czapek Dox Agarmedia (pH-5.6) and they were sub-cultured weekly and subsequently stored at 4 0 C for another 24hours. After complete drying, peels and shells were subjected to homogenization to make finepowder. These powders were sealed in air tight bottles. They were then used for solvent extraction.Extraction Procedure: The dried powder of peels and shells were extracted individually by usingsolvents such as Acetone, Methanol, Hot water & Cold Water. The powder and solvent were mixed in1:10 (Powder: Solvent) ratio in a conical flask and the flasks were plugged tightly. The temperaturefor the hot water extraction and cold water extraction were maintained at 50 0 C and room temperaturerespectively. After 24 hours, these extracts were centrifuged at 4000rpm for 5 minutes and thesupernatant was collected and this supernatant was subjected for lyophilization to evaporate thesolvent. Then the resulting dried crude extract was used in a concentration of 3mg/ml by using sterilewater for antimicrobial susceptibility testing.Bacterial and Fungal Strains & Culture Preparation: The bacterial strains used in the study wereStaphylococcus aureus, Proteus vulgaris, Lactococcus lactis, Bacillus subtilis, Escherichia coli,Klebsiella pneumonia. The fungal strains were Sporotrichum pruinosum, Candida albicans andAspergillus niger.The bacterial cultures were maintained on nutrient agar media (pH7.0). They were sub-culturedweekly and subsequently stored at 4 0 C. The fungal cultures were preserved on Czapek Dox Agarmedia (pH 5.6) and were sub-cultured weekly and subsequently stored at 4 0 CANTIMICROBIAL ACTIVITY ASSAYThe antimicrobial activity of the obtained crude samples was performed by Agar Well Diffusionmethod which is also known as Kirby Bauer or Cup Plate method.Antibacterial Activity: Sterile nutrient agar media was poured onto the sterile petriplates and allowedto solidify. After solidification 20µl of each bacterial culture was spread with a sterile glass spreaderon respective plate labeled earlier as Staphylococcus aureus, Proteus vulgaris, Lactococcus lactis,Bacillus subtilis, Escherichia coli, Klebsiella pneumonia. Using a sterile cup-borer, wells of diameterof 17.78mm were made and labeled on the back of the plate. To this, 20µl of each samples (3mg/ml)was dispensed in respective labeled wells. Bacterial plates were incubated at 37 0 C for 24hours. Afterthis the antibacterial activity of each extract was expressed in terms of mean of diameter, for the zoneof inhibition (mm) formed by addition of each extract.Antifungal Activity: Sterile Czapek Dox Agar media was transferred onto the sterile petri plates andallowed to solidify. After solidification, with a sterile glass spreader, 20µl of each fungal culture wasspread on respective plate labeled earlier as Sporotrichum pruinosum, Candida albicans andAspergillus niger. using a sterile cup-borer, wells of diameter of 17.78mm were prepared and labeledat the flipside of the plate. 20µl of each sample (3mg/ml) was dispensed in respective labeled wells.1888 J. Chem. Bio. Phy. Sci. Sec. B; 2013, Vol.3, No.3; 1886-1899.