Production of alpha amylase by Bacillus licheniformis using an economical medium.

The present study is concerned with the selection of new medium for the production of alpha amylase by Bacillus licheniformis. Different agricultural by-products such as wheat bran, sunflower meal, cotton seed meal, soybean meal, rice husk or rice bran were tested for the production of alpha amylase. Among different agricultural by-products evaluated, wheat bran was found to be the best basal and standardized medium for optimal production of alpha amylase. The production was increased 2-folds when soluble starch was replaced with pearl millet starch at 1% level and nutrient broth concentrations was reduced from 1% level to 0.5%. The newly selected fermentation medium containing (% w/v) wheat bran 1.25, nutrient broth 0.5, pearl millet starch 1.0, lactose 0.5, NaCl 0.5, CaCl2 0.2 in 100 ml of phosphate buffer. The kinetic values of Y(p/x), Y(p/s), and Q(p) indicated that the production of enzyme was greater in newly selected medium than the conventional more expensive medium.

Biosynthesis of L-DOPA by Aspergillus oryzae.

The present investigation deals with the biosynthesis of L-DOPA by parental (GCB-6) and mutant (UV-7) strains of Aspergillus oryzae. There was a marked difference between the mycelial morphology and pellet type of parental and UV-irradiated mutant culture. The mutant strain of A. oryzae UV-6 exhibited pellet-like mycelial morphology and improved tyrosinase activity. Mould mycelium was used for biochemical conversion of L-tyrosine to L-DOPA because tyrosinase is an intracellular enzyme. The mutant was found to yield 3.72 fold higher production of L-DOPA than the parental strain. The mutant strain is stable and D-glc-resistant. The comparison of kinetic parameters was also done which showed the greater ability of the mutant to yield L-DOPA (i.e., Yp/x 40.00+/-0.01 d mg/mg with parent and 182.86+/-0.02a mg/mg in case of mutant). When cultures grown for various incubation periods, were monitored for Qp, Qs and q(p), there was significant enhancement (p < 0.0025-0.005) in these variables by the mutant strain of A. oryzae UV-7 over GCB-6 on all the rates. L-DOPA (3,4-dihydroxy phenyl L-alanine) is a drug of choice in the treatment of Parkinson's disease and myocardium following neurogenic injury.

An assessment of Pakistan's urban policies 1947-1997.

PIP: This paper aims at analyzing and assessing the evolution and outcomes of Pakistan's urban policies during 1947-97. One-third of Pakistan's population live in urban areas, and the level of urbanization increased from 18% in 1951 to 32% in 1991. The rapid rate of urbanization has produced two megacities, Karachi with a population of 8-10 million and Lahore with a population of about 5 million, and 6 other cities with populations of 1 million or more. Pakistan is one of the pioneering countries in implementing physical planning and planned housing; this is reflected in its urban policies as constituted by the Five-Year Plan and national development budgets. The programs through which the policies were implemented are divided into three phases. Phase 1 (1947-70) involved the resettlement of refugees and laying of the institutional framework; core housing schemes (consisting of 1- to 2-room quarters) were the key element of the urban strategy in this period. Phase 2 (1971-78) policies were guided by the promise of mass housing, particularly for the working and lower classes. At this time, too, a set of squatter settlements known as Katchi Abadis emerged, and international organizations started funding Pakistan's urban development programs. Phase 3 (1980-95) saw the steady "privatization" of the housing and land markets and improved housing conditions, while urban policy continued to concentrate on public works, plots and construction. Despite the improvements, urban crises persist, and policies are shifting towards more complex issues of quality and the provision of new collective goods. In general, the achievements of Pakistan's urban policies have outweighed its failures, as both the rich and the poor have benefitted from them.^ieng