Investigation of rice straw and kitchen waste degradation through vermicomposting.

This study investigated the effect of vermicomposting on the degradation of rice straw and kitchen waste. Different ratios of straw and kitchen waste mixtures were used as feedstocks. After vermicomposting the substrates for 45 days under 20-25 °C moisture 60%, the vermicomposting resulted in a significant increase in phosphorous (31.38-55.89%) and potassium (33.40-63.15%), whereas a decrease was seen in TOC (38.24-43.49%) as well as TN (9.01-32.52%). The growth rate of earthworm (Eisenia foetida) was obtained in all feedstocks, the optimal rice straw/kitchen waste ratio for the earthworm growth was 3/2, excessive kitchen waste as negative impacts on the growth of earthworms. The result indicated that vermicomposting rice straw and kitchen waste with Eisenia foetida promoted nutrition content in a short period of time.

Effects of 5-azacytidine on DNA methylation and index components in patchouliol-type Pogostemon cablin / 中国中药杂志

This study aims to explore the relationship of DNA methylation with the contents of the index components as well as the growth and development of Pogostemon cablin. The demethylation reagent 5-azacytidine(5-azaC) was used to treat the tissue culture seedlings of patchouliol-type P. cablin. High performance liquid chromatography was employed to evaluate the changes of DNA methy-lation in P. cablin, and GC-MS to detect the contents of index components in P.cablin. The agronomic characters of P.cablin were measured using the common methods. The results showcased that DNA methylation of P.cablin was significantly reduced by 5-azaC in a concentration-dependent manner. Thirty days after treatment with 5-azaC at different concentrations, the content of patchouli alcohol changed slightly; compared with that in the control group, the content of pogostone in 50 μmol·L~(-1) and 100 μmol·L~(-1) 5-azaC groups was significantly up-regulated. The 100 μmol·L~(-1) 5-azaC group had the largest differences in contents of pogostone and patchouli alcohol compared with the control group, followed by the 50 μmol·L~(-1) 5-azaC group. Ninety days after disinhibition, the content of pogostone in the treatment group was significantly increased and the content of patchouli alcohol was significantly decreased. In addition, 5-azaC significantly inhibited the growth and development of P.cablin in a dose-dependent manner. These results indicate that DNA methylation regulates the biosynthesis of the index components in patchouliol-type P.cablin and proper demethylation can directly promote the synthesis of pogostone and indirectly affect the accumulation of patchouli alcohol.