50 / 2021-06-29 19:36:29

Effects of hydrolyzed polymaleic anhydride on maturity, enzymatic activity, and microbial diversity in vermicompost derived from biochemical residue of kitchen waste

Keywords: Biochemical residue of the kitchen waste; Vermicompost; Hydrolyzed polymaleic anhydride; C/N ratio; enzyme activity.

Effects of hydrolyzed polymaleic anhydride on maturity, enzymatic activity, and microbial diversity in vermicompost derived from biochemical residue of kitchen  waste

LijuanMiao,Yifan Wang, Mingyue Zhang, Yuning Feng, Feng Wang, Hangjun Zhang, Weiqin Zhu^*

College of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou 310036, PRChina

A large amount of kitchen waste is produced all over the world. However, many shortcomings emerged during disposing kitchen waste with traditional methods, biochemical disposal is one of the effective method for the reduction, safe utilization and recycle of kitchen waste. However, both high salinity and low maturity were encountered when utilizing the biochemical residue of the kitchen waste (BRKW) as a kind of organic fertilizer or nutritional soil. Aiming to reduce the high salinity and accelerate the low maturity in the BRKW, this study used the mixture of the BRKW and vermiculite as the feedstock for earthworms after hydrolyzes polymaleic anhydride was added into the mixture, focusing on revealing the effect of hydrolyzes polymaleic anhydride addition on the growth of earthworm, the basic physio-chemical properties, enzyme activity, microbial diversity of the derived vermicompost. The results showed that the addition of hydrolyzed polymaleic anhydride can promote the earthworm's growth, reproduction and biomass, the reduction was found for the pH, conductivity, organic matter content, urease activity, alkaline phosphatase activity, C/N and NH₄⁺-N/NO₃^--N in the final vermicompost, while the promotion effect was found for the contents of its total nurtion contents, catalase activity and seed germination index. The scanning electron microscopy analysis showed that there was more disintegration in the final vermicompost. Meanwhile, adding the hydrolyzed polymaleic anhydride can also help decrease the number of bacteria, fungi and actinomycetes while increase the number of nitrogen fixing, phosphorus solubilizing and potassium solubilizing bacteria in the final vermicompost of the BRKW. Hence, employing the hydrolyzed polymaleic anhydride to promote vermicomposting BRKW possibly can reduce its salt content and improve the degree of maturity in its final vermicompost, which may help the realization of the safe utilization of BRKW and furtherly promote the biochemical disposal of kitchen waste.

Keywords: Biochemical residue of the kitchen waste; Vermicompost; Hydrolyzed polymaleic anhydride; C/N ratio; enzyme activity.