Composting is a biological aerobic decomposition process consisted from different phases. Although the Japanese Standards for manure recommended that it took at least 6 months to complete the maturing phase, there was no reliable ground. In order to find out shortening method of the maturing phase, the microorganisms concerned with a progress of the maturing was determined by using the most probable number method (MPN) and PCR-RFLP of the 16S rDNA, which was found effective to provide numbers and taxonomy of polymyxin B resistant bacterial groups in the former paper [1]. Compared to the numbers after thermophilic phase, those of Actinobacteria, δ-proteobacteria, and the other gram negative bacteria increased to 50 times, 20 times, and 10 5 times, respectively, after maturing phase, while those of Bacillus spp., and α and β-proteobacteria decreased to 1/10, and 1/10 5 after maturing phase. Numbers of the other Fumicutes, and γ-proteobacteria remained in the same revel. Actinobacteria, δ-proteobacteria, and the other gram negative bacteria might be concerned with a progress of the maturing phase, because these bacterial groups were detected and enumerated due to their proliferation ability. Although number of Acitinobacteria might be underestimated because of a PCR bias, the method was found effective for the purpose to monitor bacteria actively proliferated in culture medium.

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The CaCCO process (Park et al., 2010), a sugar platform for herbaceous lignocellulosics, was modified and evaluated for fermentable-sugar recovery in solution, using rice straw (RS) as well as stems and leaves of Erianthus arundinaceus (ER), one of the strategic energy crops in Japan. Continuous wet milling of a mixture of feedstock, water and Ca(OH)2, with a weight ratio of 3/7/0.3, was adopted, not only to evaluate the applicability for wet feedstocks, but also for simultaneous Ca(OH)2 mixing with the milled feedstocks. We also applied low temperatures of 95 100 C for the alkali pretreatment to save energy. Enzymatic-saccharification tests were performed for the pretreatment slurries from 10 kg feedstocks for 72 h at 40 C under a CO2-pressurized atmosphere at 0.9 MPa with high-solid loadings of 28.4% (w/w) for RS and 27.8% (w/w) for ER. These tests successfully solubilized 80.6% (RS) and 68.1% (ER) of the total glucose-and xylose residues in the solids. Following centrifugation, the solubilized-sugar concentrations in the recovered solutions were 16.9% (w/v) for RS and 15.5% (w/v) for ER. Thus, we demonstrated that the CaCCO process could be a simple and flexible platform for preparation of dense sugar solutions from dry-and wet feedstocks, which could stimulate a new agricultural bio-industry for vitalizing rural areas.

In the present manuscript it was presented whether spreading of antibiotic resistant bacterial groups in environment could be monitored by our newly developed method by enumerating antibiotic resistant bacterial groups in various biological wastes and composts. Although the numbers were not so high, diverse kinds of colistin resistant bacteria (25 mg•L −1 ) were included in row cattle feces (1.78 × 10 4 MPN g −1 ) and cattle feces manure (>3.84 × 10 4 MPN g −1 ). Compost originated from leftover food (>44.8 × 10 4 MPN g −1 ) and shochu lee (>320 × 10 4 MPN g −1 ) included higher numbers of chlortetracycline resistant Pseudomonas sp., (25 mg•L −1 ), and row cattle feces included higher numbers of chlortetracycline resistant Enterobacteriacea (15.7 × 10 4 MPN g −1 ), which mostly consisted from Pantoea sp. or Xenorhobdus doucetiae. Numbers of multi drug resistant bacteria, resistant to 25 mg•L −1 of ciprofloxacin, streptomycin, chloramphenicol, and ampicillin, were the highest in row cattle feces (>143.6 × 10 4 MPN g −1 ), followed by cattle feces manure (4.19 × 10 4 MPN g −1 ), and shochu lee (0.36 × 10 4 MPN g −1 ), which included diverse kinds of bacterial group. The present results indicated that higher numbers of multi drug resistant bacteria were typically found in row cattle feces, and the method was found suitable to enumerate and identify them. These results suggested that the method might become their environmental risk evaluation method.

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