Non-edible Oil Cakes as a Novel Substrate for DPA Production and Augmenting Biocontrol Activity of Paecilomyces variotii

Abstract

The present study investigated the use of waste non-edible oil cakes (Jatropha, Karanja, Neem, and Mahua) as a substrate for the growth of Paecilomyces variotii and dipicolinic acid (DPA) production. Previous researches proved the efficacy of DPA in suppressing certain pathogens that are deleterious to the plants in the rhizosphere. DPA production was statistical optimized by amending non-edible oil cakes in growing media as nitrogen and sugars (Dextrose, Glucose, and Lactose) as carbon source. Plackett-Burman design (PBD), indicated that Jatropha cake, Karanja cake, and Dextrose were the most significant components (p < 0.05) of the media and were further optimized using response surface methodology (RSM). Jatropha cake, Karanja cake, and Dextrose at the concentration of 12.5, 4.5, and 10 g/l, respectively, yielded 250 mg/l of DPA, which was 2.5 fold more than that obtained from basal medium. HPLC analysis of the optimized medium (peak at retention time of 30 min) confirmed the enhanced DPA production by P. variotii. The scanning electron microscopy (SEM) images showed that optimized medium impose a stress like condition (due to less C:N ratio) for the fungus and generated more spores as compared to the basal medium in which carbon source is easily available for the mycelial growth. The antimicrobial activity of the fungal extract was tested and found to be effective even at 10−2 dilution after 72 h against two plant pathogens, Fusarium oxysporum and Verticillium dahlia. Statistical experimental design of this study and the use of non-edible oil cakes as a substrate offer an efficient and viable approach for DPA production by P. variotii.

Solid-state fermentation technology and innovation for the production of agricultural and animal feed bioproducts

“…1d) a modular design patented by Biocon Ltd. claimed for a self-contained SSF device that combined all fermentation operations i.e., sterilization, inoculation, cultivation, extraction and post-extraction treatment, in a single unit. It was validated for sterile production of proteases, cyclosporine, amylases and lovastatin [15,32,34].…”

“…This non-sterile bioreactor is equipped with controls for process parameters (air-inlet temperature, air flow rate and agitation period). Different working volumes are available, but a maximum layer thickness of [15,32,34] 50 cm is used. Substrate is prepared and inoculated in other equipment before filling the reactor [14,15,32].…”

Synergistic effect of oilseed cake and biocontrol agent in the suppression of Fusarium wilt in Solanum lycopersicum

“…In in vitro test, nanshancha seed cake (Camellia semiserrata Chi) showed percentage inhibition of 100, 90.9, 85.3% against Colletotrichum musae, C. gloeosporioides, and Penicillium italicum, respectively [36]. Few researchers have reported the antagonistic effect of oilseed cakes against fungal phytopathogens that support the biocontrol efficacy of oilseed cake in the present study [9,36]. Furthermore, in the present study, solid-state fermentation of F. oxysporum on mustard cake showed an inhibitory effect on spore production.…”

“…Tiyagi [10] reported that damage caused by nematodes in Vigna radiata was less pronounced after a combined application of oilseed cake and Pseudomonas fluorescens. Arora [9] assessed the efficiency of oil cake as a novel growth substrate for Paecilomyces variotii that augmented its antagonistic activity against F. oxysporum and Verticillium dahliae. These earlier studies provided an approach for the present work to utilize mustard cake in combination with biocontrol agents.…”

“…Boosting the suppressive potential of soil with the amendment of organic matter is one of the biological techniques available to control a wide range of pathogens. Several studies have suggested the utilization of different agro-industrial wastes such as manure, oilseed cakes (OSCs), and compost, as soil amendments for the control of plant pathogens [8,9].…”