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The present greenhouse study was undertaken to evaluate the effects of co-inoculating methylotrophic Methylobacterium oryzae CBMB20 along with nitrogen-fixing Azospirillum brasilense CW903 or a phosphate solubilizing bacterium Burkholderia pyrrocinia CBPB-HOD on the growth and nutrient uptake of tomato, red pepper and rice. Seed inoculation and soil/foliar application of the bacterial strains alone or under dual inoculation increased the plant growth in terms of shoot or root length and increased the nutrient uptake in the plants studied compared to uninoculated control plants. Co-inoculation of M. oryzae CBMB20 with A. brasilense CW903 or B. pyrrocinia CBPB-HOD improved the N and P concentration of plants, while the results varied among the plant species tested. Also, co-inoculation of the bacterial strains increased the activity of nitrogenase, urease and phosphatase enzymes in soil when compared to uninoculated control or individual inoculations. Though the inoculation effects were analyzed at an early stage of plant growth, the results conclusively suggest that M. oryzae being compatible with other microorganisms in the rhizosphere can potentially be used as individual inoculant or co-inoculated with other plant growth promoting bacteria to increase the production in sustainable agricultural systems.

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Poly(butylene succiate) (PBS), poly(butylene succinate-co-L-lactate) (PBSL), and poly(butylene succinate-co-6-hydroxycaproate) (PBSCL) polymers were degraded by lipase PS ® , and the enzymatic degradation mechanism of PBS was analyzed in detail. The enzymatic degradation of PBS gave 4-hydroxybutyl succinate (4HBS) as the main product. An exo-type hydrolysis mechanism was proposed based on this observation. The terminal chain of PBS had conformational similarity to ordinary tri-and diglycerides and could be incorporated as a substrate in the active site of this lipase. The surface adsorption of the lipase was much larger on PBS and its copolymer films than on the other polyester films because the lipase adhered quite strongly to the polymer terminal through a specific adsorption mechanism. Kinetic analysis showed that the total number of surface adsorption points per unit area of PBSL and PBSCL copolymers was larger than that of the PBS homopolymer.

This study was conducted to determine whether differential soil properties in bulk and rhizosphere soil could influence cation‐exchange equilibria. The pH of rhizosphere samples collected from peach [Prunus persica (L). Batsch var. persica] seedling roots grown in Arbuckle gravelly loam (fine‐loamy, mixed, thermic Typic Haploxeralf) were 0.4 units lower than bulk soil. Organic C content, cation‐exchange capacity, clay, and amorphous oxide content were higher in the rhizosphere. Mineralogical differences apparent to x‐ray analysis were not evident. As soil pH decreased, the selectivity for NH4 over Ca increased but pH effects on NH4‐K exchange were insignificant. Organic matter addition increased the selectivity for NH4 over K, and Ca over NH4. As exchange solutions were diluted, the selectivity of the higher valent cation increased. Although the effect of individual soil properties on the exchange reactions could be fully determined, there were significant differences in the exchange equilibria between the bulk and rhizosphere soil. In the rhizosphere samples, selectivity for NH4 over K was relatively higher at an ionic strength of 0.02, but selectivity reversed at an ionic strength of 0.05. At ionic strengths of 0.02 and 0.05, the selectivity for NH4 over Ca was higher in the bulk soil. The differential exchange equilibria between bulk and rhizosphere soils are expected to affect cation distributions in the soil environment around roots, nutrient uptake, and toxicity relations of plant roots.