Seroprevalence of leptospirosis among suspected cattle in eastern part of India: a comparative study between rLipL32ELISA and MAT

Leptospirosis in cattle is a worldwide problem associated with abortion, agalactia, still birth and infertility resulting in major economic losses to dairy industry. There is lack of data regarding seroprevalence of bovine leptospirosis in eastern India. So, with the aim to investigate the prevalence of the disease in OdishaandWest Bengal state of eastern India, a total of 350 cattle serum samples were collected with distinct geographical attributes having history of infertility, abortion, and haemogalactia. Serum samples were tested by microscopic agglutination test [MAT] using a battery of twelve Leptospira serovars as live antigen to detect the serovars present in the studied area. Further a recombinant protein [LipL32] based ELISA was carried out for comparative study. Overall seropositivity using MAT and rLipL32ELISA were found to be 50.85% and 56%, respectively. The sensitivity and specificity of rLipL32ELISA relative to MAT was calculated and found to be 100% and 89.53%, respectively. In the current study among the serovars, icterohaemorrhagiae was the most predominant serovar reported in this study. So to conclude, this study warrants further investigations in this area to establish the risk factors involved in disease transmission cycle. Key words: Cattle, Leptospirosis, MAT, rELISA, India

Optimization of operational parameters for ethanol production from Korean food waste leachate

Recently, research on the production of ethanol from waste has been accelerating for both ecological and economical reasons, primarily for its use as an alternative to petroleum based fuels. In this study, response surface methodology based 2[3] -full factorial central composite design was employed to optimize the parameters of ethanol production from Korean food waste leachate. The reducing sugar concentration of the food waste leachate determined by the dinitrosalicylic acid method was 75 g/L. A second order polynomial model was developed to evaluate the quantitative effects of temperature, pH and reducing sugar concentration in order to find an optimum condition for the ethanol production from food waste leachate. From the experimental result, maximum ethanol concentration of 24.17 g/L was obtained at the optimum condition of temperature [38°C], pH [5.45] and reducing sugar concentration [75 g/L]. The experimental value [24.17 g/L] agreed very well with the predicted one [23.66 g/L], indicating the suitability of the model employed and the success of response surface methodology in optimizing the conditions of ethanol production from food waste leachate. Canonical analysis indicated that the stationary point was a saddle point for the ethanol yield. Despite being a waste, an ethanol yield of 0.32 g ethanol/g reducing sugar demonstrated the potential of food waste leachate as a promising biomass resource for the production of ethanol

Influence of dissolved oxygen concentration and aeration time on nitrite accumulation in partial nitrification process

This study investigated the influence of dissolved oxygen concentration and aeration time on nitrification and nitrite accumulation in an attempt to optimize the recently developed biological-partial-nitritation process for the treatment of strong nitrogen wastewaters. Investigation of dissolved oxygen concentration on ammonium and nitrite oxidation was carried out in a batch reactor. The dissolved oxygen concentration of 0.5 mg O2/L inhibited both ammonium as well as nitrite oxidation, while increase of dissolved oxygen concentration to tilde1 mg O2/L increased the ammonium oxidation rate and was comparable to that at higher dissolved oxygen concentrations. Experiments were carried out in a sequencing batch reactor for more than 100 days to investigate the influence of aeration time on nitrite accumulation. The dissolved oxygen concentration was controlled at tilde1.0 mg O2/L [in the range of 0.8-1.5 mg/L] during the aeration stage, and volatile suspended solid was maintained at 2.0 g/L while temperature and pH were 30 +/- 1§C and 8.3 +/- 0.1, respectively. In a typical cycle, complete nitrification occurred at aeration time longer than 6 h. When the aeration time was reduced to 4 h., tilde80% of partial nitritation was achieved. With a further reduction in aeration time to 3 h., nearly 1:1 nitrite/ammonium ratio was yielded. This result revealed that for the reactor design, aeration time determined by feasibility experiments must be considered based on the nitrogen strength in wastewater and biomass concentration in the reactor with dissolved oxygen concentration of tilde1.0 mg O2/L for satisfactory partial nitrification with subsequent processes such as anaerobic ammonium oxidation

Performance of upflow anoxic bioreactor for wastewater treatment

Laboratory scale studies were conducted in an up-flow anoxic bioreactor [UFAB] using synthetic fertilizer wastewater for ascertaining the denitrification efficiency. The performance of the reactor was compared using ethanol and topioca starch as the carbon source. The initial NO3-N concentrations [50-250 mg/L] and hydraulic retention time [HRT, 12-24 h] were varied to evaluate the COD and NO3-N removal. The results from this study shows that ethanol gave very good denitrification efficiency [78-98%] compared to topioca starch [68-96%]