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A new biodiesel-like biofuel is obtained by the enzymatic ethanolysis reaction of sunflower oil with ethanol, in free solvent media, by using BIOLIPASE-R, a multipurpose alimentary additive from Biocon®-Spain that is a low cost lipase from a strain of Rhizopus oryzae. This biofuel is composed by two parts of fatty acid ethyl esters (FAEE) and one of monoglyceride (MG), which in this form integrates glycerol, through the application of the 1,3-selective lipases. Thus, this process minimizes waste generation and maximizes the efficiency of the process because no residual glycerol is produced. Response surface methodology (RSM) is employed to evaluate the main reaction parameters (reaction temperature, oil/ethanol ratio and pH) on the sunflower oil conversion. Water content and amount of lipase were also previously investigated. Regarding the results, we found that it operates optimally with a water content of the reaction medium of 0.15%, 0.05%-0.1% lipase by weight relative to the weight of oil used, 20 °C, volume ratio (mL/mL) oil/ethanol 12/3.5 and pH 12 (by addition of 50 μL of 10 N NaOH solution). These results have proven a very good efficiency of the biocatalyst in the studied selective process. [ABSTRACT FROM AUTHOR]

Simple Summary: Milk is an important transmission route of Mycobacterium avium subsp. paratuberculosis (MAP) for dairy calves. The aim of the present study was to assess the efficacy of milk treatments to prevent MAP infection transmission to calves. A one-year field longitudinal study was carried out. Newborn calves were assigned to one of four experimental groups. MAP numbers were estimated for treated and untreated milk. Infection progression was monitored monthly. After one year, calves were euthanized, and tissue samples examined grossly and by histopathology. Milk treatments were highly effective though MAP shedding was also observed in all groups. It was not enough to try to block MAP infection transmission controlling only the quality of milk consumed by calves. One of the important routes of Mycobacterium avium subsp. paratuberculosis (MAP) transmission in dairy calves is milk. The aim of the present study was to assess the efficacy of milk treatments to prevent MAP infection transmission to calves. A one-year longitudinal study was carried out. Newborn calves were assigned to one of four experimental groups: 5 calves received naturally MAP-contaminated milk, 5 calves received copper treated milk, 4 calves were fed calf milk replacer, and 3 were fed UHT pasteurized milk. MAP load in milk was estimated. Infection progression was monitored monthly. After one year, calves were euthanized, and tissue samples were cultured and visually examined. MAP was undetectable in milk replacer and UHT milk. Copper ion treatment significantly reduced the number of viable MAP in naturally contaminated milk. Fecal shedding of MAP was observed in all study groups but began earlier in calves fed naturally contaminated milk. Paratuberculosis control programs must place multiple hurdles between the infection source, MAP-infected adult cows, and the most susceptible animals on the farm, young calves. As our study shows, strict dependence on a single intervention to block infection transmission, no matter how important, fails to control this insidious infection on dairy farms. [ABSTRACT FROM AUTHOR]