Vermicomposting of various solid agro-wastes using Eisenia fetida and identification of normal flora from its mid-gut

Abstract

Vermiculture composting is the process of producing the compost using earthworms to change the organic wastes in to high quality compost that consists mainly of worm cast in addition to decayed organic matter. This Research was aimed to perform vermicomposting of various solid agro-wastes using Eisenia fetida and identification of normal flora from its mid-gut. solid waste such as Kchat, paper, cow dung and vegetable wastes were collected and transported into composting room. E. fetida was collected from Awash Melkasa research center. For the screening of the normal flora, the samples were taken from the mid-gut of E. fetida at the beginning of the composting and at the end of the composting on 45thday from each vermicomposting treatments. The Physico-chemical properties of wastes, isolation of the normal flora from the mid-gut of E. fetida, biochemical characterization of screened potential isolates, and optimization of potential bacterial isolates these obtained from the mid gut of E. fetida were conducted. The data were analyzed using Microsoft excel 2010 version, and origin 2019b version. During Physico-chemical analysis, minimum and maximum pH value was obtained. The highest (9.34±0.046) pH mean values for vermicomposting were obtained from vegetable composting due to E. fetida. A considerable amount of electrical conductivities were detected Kchat and vegetable vermicomposting processes. Total organic carbon (TOC) and total nitrogen (TN) contents were also detected for the vermicomposting processes. A 17 type of normal flora of E. fetida these suggested to assist biotransformation of these wastes were identified using Matrix assistant laser Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI TOF MS). Certain of these obtained isolates were including .such as Bacillus. Anthracis BPW-1, B. megaterium BPW-4, B. cereus BKW-4, B. flexus BKW-31, B. pumilus BKW-3, B. subtilis BKW-5, Enterobacter cloacae EKW-5, E. hormaechei EKW-5, Serratia rubidaea SRVW-5 and Staphylococcus hominis SVW 51. Optimization for certain potential isolates which obtained from the mid gut of E. fetida were determined and glucose, maltose, mannitol, peptone, KNO3 and Yeast extract (YE) were found to be employed for growth of B. subtilis BKW-5, B. flexus BKW-31 and B. cereus BKW-4