The effect of environmental factors on the hydrolysis characteristics of Lipase

The effects of environmental and composition factors, such as reaction time, metal ions, pH, agitation speed, the weight ratio of water to oil, and the weight of enzyme, on the hydrolysis of oils by Lipase-OF were investigated. In case oils with low melting point, the optimum temperature of hydrolysis where the enzyme activity was maximum was 37 degrees centigrade. However, When the melting temperature was higher than 40 degrees centigrade, the optimum temperature was around the fusion temperature. The activity of Lipase-OF decreased very rapidly with the increases of temperature in the range of higher than 45 degrees centigrade and the ctivity perished above 65 degrees centigrade. The effect of agitation speed was investigated from 150 to 650 rpm. The hydrolysis of oils increased as the agitation speed increased up to 350 rpm, but it did not increase any more above 350 rpm. The weight ratio of water to oil was changed from 1:9 to 9:1 for the investigation of the effect on the hydrolysis. The weight ratio for maximum hydrolysis was 1:1. Ca2+ and Mg2+ among various metal ions had some effect on the stimulation of hydrolysis. The optimum concentration of the ions was about 100ppm at which the hydrolysis increased, compared with that of distilled water, by 2 to 3%. The Optimum pH of Lipase-OF was 7. The hydrolysis decreased as the pH decreased and also decresed as the pH increased. The content of enzyme affected the hydrolysis of oil. The hydrolysis increased with the content of Lipase-OF in the range of less than 0.013 wt% of substrate. However, the increase of hydrolysis wkth the content of Lipse-OF ceased above 0.013 wt%. The experiments investigating the effect of environmental and composition factors on the hydrolysis of oils showed that the optimum temperature was 37 degrees centigrade, the pH7, the concentration of Ca2+ or Mg2+ 100 ppm, the agitation speed 350 rpm, the weight ratio of water to oil 1:1, and the content of Lipase-OF 0.013 wt% of substrate.