The fatty acid compositions of the major cerebral cortex phospholipids, phosphatidylcholine, phosphatidylethanolamine, and phosphatidylserine were measured in 16 term and one preterm 'cot death' infants fed exclusively either breast milk or one of two formulas. Docosahexaenoic acid (DHA; C22:6n-3) content in cerebral cortex phosphatidylethanolamine and phosphatidylserine of breast fed infants was greater than in both formula groups with significances varying between p<001 and p<0001. Compensation for this deficiency in DHA in the formula fed infants was largely achieved by increased incorporation of docosapentaenoic acid (C22:5n-6) in the cerebral cortex of term infants and Mead (C20:3n-9) and dihomo Mead acids (C22:3n-9) in the preterm infant.As the phospholipids most affected are known to perform an important role in membrane fimction and are possibly integral to neurotransmission it is recommended that breast milk substitute infant formulas should contain n-3 and n-6 series polyunsaturated fatty acids in proportions similar to those ofhuman milk. (Arch Dis Child 1995; 72: 198-203) Approximately 60% of the total energy intake of the infant during the first year is utilised by the brain and much of this energy is used to synthesise neuronal membrane and deposit myelin. Fatty acids from human milk or infant formulas provide not only a source of hydrocarbon for energy production but help synthesise the complex hydrocarbon structures necessary for the creation of neurotransmitter membranes.Breast fed infants have significantly greater concentrations of the long chain polyunsaturated fatty acid (PUFA), docosahexaenoic acid (DHA; C22:6n-3) in their cerebral cortex phospholipids than infants fed current infant formulas.2 3 Cerebral cortex neuronal membrane phospholipids are composed of phosphatidylcholine, phophatidylethanolamine, phosphatidylserine, and phosphatidylinositol. While the membrane receptor and secondary messenger characteristics of phosphatidylinositol and its meta-

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The Catalase (H2O2 oxidoreductase, EC.1.11.1.6) is an enzyme that catalyses the decomposition of hydrogen peroxide to oxygen and water to protect the cell against oxidative stress. The aim of current study is to observe the effect of increasing oxidative stress on the catalase synthesis. Results of the study shows that the increase in oxidative stress by adding 0.1 % cholesterol in medium raises the catalase production by B. Subtilis KIBGE HAS 1. The molecular mass of this partially purified catalase was found to be 210 kDa by native PAGE. The enzyme was purified up to 8.9 %. The enzyme exhibits high thermal stability and retain 80.2 % of its original activity when stored at 50°C for 120 min. with Km and Vmax of 41.89 mM and 77.97 U/mg of protein respectively. Among various metal ions, Na+, Ca+ and Ba+ ions enhance the catalase activity however; Hg+ causes an inhibitory effect. The findings of this study give advantage to industries regarding augmentation of catalase production by generating the oxidative stress and therefore indirectly increase the production of enzyme.

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