Development and formulation of effective microbial (EM) technology for dairy industrial effluent treatment

Dairy Industries produce nearly thousands of litres of effluent waste per day. This waste with high intense foul odour pollutes ecosystem and ground water, harbour pathogens causing health hazards. Various pre-treatments methods are available to neutralise the effects. But, bioremediation with EM technology is ecofriendly and helps to clean up contaminated environments through the use of microorganisms. EM technology meaning Effective Microorganisms consisting of beneficial and highly efficient microbes that are non-harmful, non-pathogenic, not-genetically-engineered or modified (nonGMO), and not-chemically-synthesized. This is proven safe, lowcost, effective and easily utilized in environmental protection. In the present study, dairy industry effluent was analysed for microbial content and five different microbes were isolated and labelled as MB1, MB2, MB3, MB4 and MB5. All these were Gram negative, rod shaped and motile. The MB1 colonies displayed Green fluorescence when exposed to UV light; hence it was completely characterized and revealed to be Pseudomonas aureginosa. Biochemical analysis for reducing sugar, protein, lipids was carried out. Also BOD, COD was analysed. Qualitative analysis of Lipids was done by TLC using sprays of ninhydrin solution and molybdic acid which indicated the presence of cholesterol and phospholipids respectively. Quantitative analysis of reducing sugars by Anthrone's test and proteins by Lowry's method gave a result of total carbohydrate content of 500μg/ml and protein content of 100μg/ml. EM mixture used for effluent treatment included Lactobacillus acidophilus, Chromatium Species, Mucor heimalis, Streptomyces greiceus, Aspergillus Oryzae, Yeast, and Pseudomonas isolated from effluent tank. All the organisms were grown on different media and treated directly on 100 ml of effluent and studied for changes in three parameters viz., pH range 3-4, odour reduction to 1 in the scale of 1-5 [ 1least/no odour, 5 - foul odour] and clearance of effluent. Except Chromatium sp., others were selected since there was no much change in parameters when Chromatium sp was used. For better results Jaggery solution was used to ferment all the organisms. Sample of effluent used was 400 ml. Odour reduction was observed after 15 days of treatment. For cost optimization sugarcane juice was used as substrate for fermentation and few more organisms were tried along with the existing EM Mixture. The organisms included lactic acid producing bacteria, Rhodopseudomonas sps and methanotroph. Sugarcane juice was fermented with different combinations of these organisms and treated on 250 ml of effluent sample. Totally 52 different combinations of EM mixture were tried, out of which 4 effective EM combinations (EM1, EM2, EM3 and EM4) were identified based on three parameters. These 4 EM mixtures were studied for scaled up effluent treatment (1litre) and it was observed that EM1 and EM2 were found to be effective in forming higher clearance in effluent turbidity with reduction in foul odour and pH , there by rendering the effluent fit for safer disposal. Pot studies were conducted using these EM mixtures for germination and growth of seedlings of Ragi crop. It is observed that the EM treated seeds were first to emerge and establish compared to the untreated control. When added EM solution to the plants, the vegetative growth of the seedling was fast. Also, treated effluent was added to Ragi seedlings. This indicated that EM mixtures stimulate germination and growth related hormones of the crop. These EM1 and EM2 mixtures are maintained as stock cultures in 2.5 litres of sugarcane juice as organic substrate for microbial growth in glass jars. These two EM mixtures can be studied further for field application with proper active formulation for better vegetative growth and yield.