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Despite the prevalence of starch-hydrolyzing enzymes in bacilli, relatively few have been studied in detail. In an attempt to isolate an effective α-amylase-producing strain, Bacillus globisporus BH-1b has been isolated. The strain requires few nutritional supplements and shows induction in the presence of galactose. 2% potassium nitrate and pH 7.2 emerged as optimum for the fermentation medium. The durability of the enzyme has also been tested at a low pH and a high temperature.

Microorganisms are the dominatign inhabitants of the soil, and there is an icnreasing tendency to apply heavy metals in agricultural practice. The ecological balance may be distrubed unknowingly if we do nogt measure the tolerance by the microorganisms of these heavy metals. It has been found in a Oscillatoria model system that widely used heavy metals have a high degree of toxicity to this cyanobacter.

A hydrocarbon utilizing strain of Micrococcus varians 2Fa isolated from local soil has been found to yield lysine 2.6 g l −1 . Addition of B-vitamins and trace elements to the optimal media, has been found to stimulate growth and enhance lysine yield

Activity of DAP-decarboxylase in lysine overproducing strains of Micrococcus luteus, M. varians and Arthrobacter globiformisLb reached the highest level during the end of the exponetial phase of growth and remained at the same high level during the stationary phase of growth when major bulk of lysine was accumulated. In comparison in a lysine non-producing strain of Arthrobacter globiformis I 4 the activity of the same enzyme was low. DAP-decarboxylase of these three lysine overproducers has two specialities, persistence during the stationary phase and insensivity to repression by exogenous lysine.

A hydrocarbon utilizing strain of Arthrobacter globiformis Lb isolated from local soil has been found to yield lysine 3.4 g l−1, keeping the medium optimal for pH, C- and N-sources. Addition of antibiotics and micronutrients to that optimal media stimulated cell growth and enhanced lysine yield.