METHODS AND RESULTS: The results showed that the bioprocess of T. harzianum K179 bioagent production in a laboratory bioreactor on the medium with optimal composition (dextrose 10 g l-1, soy flour 6.87 g l-1, K2HPO4 1.51 g l-1, KCl 0.5 g l-1, and MgSO4 × 7H2O 0.5 g l-1), at stirring speed of 1.75 × g and aeration intensity of 1.5 vvm, can be shortened from 96 to 36 h. The results of bioprocess economic analysis showed that with a 25-year project lifetime and an investment payback time of 7.58 years, this project represents an economically viable system.
CONCLUSIONS: Complete analysis of the bioprocess of T. harzianum K179 biocontrol agent production showed that the biologically produced preparation can be competitive on the market with synthetic preparations.
AIM OF THE STUDY: This study's primary aim was to investigate the effect of a cultivated fruiting body of O. sinensis strain (OCS02®) on airways patency and the secondary focus was to investigate its effect on the lifespan of Caenorhabditis elegans.
MATERIALS AND METHODS: A cultivated strain, OCS02®, was employed and the metabolic profile of its cold-water extract (CWE) was analysed through liquid chromatography-mass spectrometry (LC-MS). Organ bath approach was used to investigate the pharmacological properties of OCS02® CWE when applied on airway tissues obtained from adult male Sprague-Dawley rats. The airway relaxation mechanisms of OCS02® CWE were explored using pharmacological tools, where the key regulators in airway relaxation and constriction were investigated. For the longevity study, age-synchronised, pos-1 RNAi-treated wild-type type Caenorhabditis elegans at the L4 stage were utilised for a lifespan assay.
RESULTS: Various glycopeptides and amino acids, particularly a high concentration of L-arginine, were identified from the LC-MS analysis. In airway tissues, OCS02® CWE induced a significantly greater concentration-dependent relaxation when compared to salbutamol. The relaxation response was significantly attenuated in the presence of NG-Nitro-L-arginine methyl ester (L-NAME), 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ) and several K+ channel blockers. The longevity effect induced by OCS02® CWE (5 mg/mL and above) was observed in C. elegans by at least 17%.
CONCLUSIONS: These findings suggest that the airway relaxation mechanisms of OCS02® CWE involved cGMP-dependent and cGMP-independent nitric oxide signalling pathways. This study provides evidence that the cultivated strain of OCS02® exhibits airway relaxation effects which supports the traditional use of its wild O. sinensis in strengthening respiratory health.
METHODS AND RESULTS: Five pathogen: antagonist inoculum ratios (100:0, 75:25, 50:50, 25:75, and 0:100) were employed. Non-aflatoxigenic Aspergillus flavus Af1KD and Af5TD, and Penicillium janthinellum were used against aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) by A. flavus. Against OTA by A. niger, and fumonisin B1 (FB1) and fumonisin B2 (FB2) by Fusarium verticillioides and F. proliferatum, respectively, the antagonists Trichoderma asperelloides, T. asperellum, and T. harzianum were used. Non-aflatoxigenic A. flavus Af1KD was the most effective against AFB1 and AFB2 at all tested ratios and substrates. All Trichoderma spp. were effective against OTA by A. niger on grain corn agar at all tested ratios. Trichoderma asperelloides and T. asperellum were effective against FB1 and FB2 produced by F. verticillioides at all tested ratios and substrates. Trichoderma asperelloides was effective against FB1 and FB2 by F. proliferatum at all tested ratios and substrates.
CONCLUSION: The native biocontrol candidates were effective against mycotoxigenic fungi and mycotoxin production on grain corn agar and grain corn kernels, and could be developed into biocontrol agents.