Microbiological Parameters of Different Waste Waters to Evaluate Their Potential to be Use as a Media for Chlorella sp. and Spirogyra sp. Cultivation

Globally there is severe water scarcity, and methods to reuse wastewater need to be adapted. The objective of this research was to determine the microbiological parameters of different wastewaters in order to study the potential of wastewater as a media to cultivate algae.Food, agriculture, drainage and municipal wastewater sample were collected in sterile bottles separately. Aerobic, anaerobic plate counts, yeast and mold counts were evaluated. Enumeration of coliform, fecal coliform, coliphages and microalgae was performed with all wastewater samples. Chlorella sp. and Spirogyra sp. were isolated from three different paddy field water samples, and growth studies were carried out in different wastewater media with standard sterile Chu’s medium and in sterile tap water medium as control.Heterotrophic, anaerobic bacteria, microalgae, yeast and molds were found in all types of wastewater. Agriculture wastewater had the highest value for aerobic, anaerobic, yeast and mold count in the highest dilution. Coliforms and fecal coliforms were absent in food and agriculture wastewaters on Eosin Methylene Blue (EMB) medium. Coliform and Fecal coliforms were only observed in drainage and municipal wastewater on Endo agar (EA) medium. Coliphages were absent only in agricultural wastewater and found in the highest numbers in municipal wastewater. Except for agricultural wastewater, other three types of wastewaters contain microbial contaminations. Agriculture wastewater medium significantly enhanced the growth of Chlorella sp. than the standard Chu’s medium. The growth of Spirogyra sp. was stimulated by the food wastewater medium than the other media. Keywords: Wastewaters, Microbiological parameter, Chlorella sp., Spirogyra sp., Coliform

Occurrence of Lactobacilli in the Traditional Preparation of Curd

Curd is a dairy product produced via way of means of coagulating milk in a process known as curdling. The objective of this current study was to prepare curd traditionally in the laboratory and identify Lactobacilli species with potential probiotic activities. Cow and goat milk was collected, and curd was prepared by adding lime and starter culture in different amounts. Among prepared curd samples, best quality curd was selected, and from the selected curd samples, lactic acid bacteria were isolated and subsequent subculturing was carried out, and ten different Lactobacilli isolates were obtained and identified based on morphological, physiological and biochemical characteristics.Isolates were subjected to test the antagonistic effect among the Lactobacilli isolates and against selected bacterial strains by standard agar well diffusion method. Antibiotic sensitivity test by disc method was carried out by using antibiotics and the production of lactic acid by titration method.Ten different Lactobacilli isolates were classified into three different genera Lactobacillus sp., Pediococcus sp. and Leuconostoc sp. Growth of all Lactobacilli was observed under acidic and neutral pH. Lactic acid bacteria exhibited different tolerant levels to bile salt. No antagonistic effect was observed among the Lactobacilli isolates. But 80% of lactobacilli isolates had antibacterial activity on selected bacterial species. The growth of Bacillus sp. was predominantly inhibited by Lactic acid bacterial isolates (90%), Pseudomonas aeruginosa (30%), Proteus sp. and Staphylococcus aureus (50%) and E.coli (30%). Lactobacillus sp. (CL2) predominantly inhibited all tested bacteria (100%). Growth of the Lactobacilli isolates was inhibited by tested antibiotics except for Lactobacillus sp. (CC3) was resistant to bacitracin only. All of the Lactic acid bacterial isolates produced a considerable amount of lactic acid. Under the controlled conditions, the Lactobacillus sp. (GL1) produced a significantly high level of lactic acid (0. 315%), whereas Lactobacillus sp. (CL3) produced less amount of lactic acid (0.099%). Keywords: Curd, Lactic acid bacteria, Antagonistic effect, Antibacterial sensitivity, Lactic aci