supplementary materials to https://doi.org/10.1016/j.jenvman.2020.111252
This data describes the supplementary materials (additional Figures, and Tables) for the article https://doi.org/10.1016/j.jenvman.2020.111252 Thermoacidophilic effective microbes (tEM) were used to enhance the composting process of lignocellulosic waste. Composting with tEM slightly reduced NH3 emission during the composting process while CH4, and CO2 patterns positively correspond to the rate of composting, with higher emissions in tEM treatment during 60d – 90d composting. Compost microbial evolution based metagenomic DNA sequencing and culture-based microbial enumeration indicate higher abundance and diversity of microbes in tEM treated groups especially at thermophilic temperatures. Chemical analysis showed higher rate of mineralization in tEM treated compost compared to control group while the heavy metal content was below the international threshold levels in both treatment and control. Moreover, germination index (Gi) and global germination index (GI) were higher in tEM treated compost compared to control group. The data is important for evaluating composting efficiency and quality of the final compost product.
Steps to reproduce
The steps to reproduce this data is described in the section: Experimental Design, Materials, and Methods Composting materials were treated with microbial inoculum and composted for 120d with or without shading. Three treatment groups: 1) tEMA – tEM treated compost with shading; 2) tEMB – tEM treated compost without shading; and 3) C – non-tEM control without shading were used as described in the main article . Gas/Biogas production: H2S (ppm), CO2(%), O2 (%), and CH4 (%) production were measured using a biogas analyzer (Optima7 MRU Instruments Inc. Emission monitoring systems, Humble, Texas, USA). NH3 was analyzed by pumping 50 cm3 biogas through 2% Boric acid (pH of 4.5) using ETG 6900 P Ammonia (Etg Risorse & Tecnologia, Carpignano 23 Montiglio (AT) – Italy). And ammonium borate complex titrated with 0.05N H2SO4 and concentration of ammonia gas was calculated based on moles of standard acid consumed. Compost chemical analysis: Cations (K+, Ca2+, Mg2+, and Na+) were analyzed using inductively coupled plasma, atomic emission spectroscopy (ICP-AES) on Perkin Elmer, Optima 8300 (Thermo Fisher Scientific Solutions Co. Ltd., Seoul, Korea). Cation exchange capacity (CEC) was analyzed using the Ammonium acetate saturation (AMAS) method according to . Germination assay: To test for compost phytotoxicity, germination index (Gi) at compost concentrations of 25%, 50%, and 75% and global germination index (GI) (the average Gi at 50% and 75%) were determined as described previously [3, 4]. Microbial population and diversity: microbial evolution during composting was studied over 120d period based on metagenomic DNA sequencing (16S RNA gene sequences, targeting the V3-V4 region for bacteria and archaea ) and culture-based microbial enumeration at thermophilic and mesophilic temperatures. Pyrosequencing and metagenomic analysis of compost samples was conducted at Macrogen Inc., Seoul, Korea. Briefly, two replicates of at least 20 composite samples (kept at – 80 ⁰C) was homogenously mixed and used for DNA extraction and sequencing. Similar sequences were pooled together to minimize computation . The reported number of sequences are an average of two replicates. DNA was extracted from 0.5g aliquots of each sample using Powersoil® DNA Isolation Kit (MO BIO Laboratories Inc., Carlsbad, CA, USA) according to the manufacturer’s protocol. See details in attachment (Description of supplementary Materials).