Isolation, Characterization and Development of Psychrotrophic Consortium for Potential Degradation of Paddy Straw at...

The aim of the study was to investigate the enzyme production of psychrotrophic lignocellulolytic, silicolytic, and xylanolytic fungi for the development of the consortium at low temperature paddy straw degradation. To achieve this, a series of enrichment, isolation, and screening steps were conducted, resulting in the isolation of twenty-one fungi from cold-adapted regions, namely Balim, Gurdaspur, Punjab. In the qualitative screening at 15 °C, a total of thirteen fungal isolates were selected. These screened isolates were further subjected to quantitative estimation of different enzymes at three low temperatures (10, 15, and 20 °C). The maximum enzyme production was observed in isolate LTF 7 for CMCase and LiP, in LTF 21 for FPase, in LTF 1 and 5 for xylanase, in LTF 13 for laccase, and in isolates LTF 16, 17, and 19 for MnP and silicase. Furthermore, based on the data, tolerance of low temperature was checked by radial growth measurement at 15 °C, resulting in 100% growth for isolates LTF 1, 7, 13, 16, 17, and 21 under 7 days of incubation. The survivability of those isolates was also checked for adaptation in the colder region through a freeze-thawing experiment, in which, LTF 13, 21, 1 and 7 recorded maximum population in a series of 20 days experiments. Cross compatibility assay was used to develop the different consortia and its efficiency was checked by different degradation assays using paddy straw at low temperature (15 °C). Among the various experiments, the consortium named LTF 1-13-21 recorded the highest degradation efficiency and ITS sequences of isolates 1, 13 and 21 were identified as Penicillium aethiopicum, Penicillium echinulatum and Penicillium chrysogenum. This study not only indicated a valuable psychrotrophic paddy straw degrading strain but also offered meaningful evidence for further exploration of the microbial degradation mechanism in cold regions.