Enhanced fermentative production of Cephalosporin C by magnetite nanoparticles in culture of Acremonium chrysogenum

Histidine modified Fe3O4 nanoparticles improving the ethanol yield and tolerance of Saccharomyces cerevisiae

Saccharomyces cerevisiae, the primary microorganism involved in ethanol production, is hindered by the accumulation of ethanol, leading to reduced ethanol production. In this study, we employed histidine-modified Fe3O4 nanoparticles (His-Fe3O4) for the first time, to the best of our knowledge, as a method to enhance ethanol yield during the S. cerevisiae fermentation process. The results demonstrated that exposing S. cerevisiae cells to Fe3O4 nanoparticles (Fe3O4 NPs) led to increased cell proliferation and glucose consumption. Moreover, the introduction of His-Fe3O4 significantly boosted ethanol content by 17.3% (p < 0.05) during fermentation. Subsequent findings indicated that the increase in ethanol content was associated with enhanced ethanol tolerance and improved electron transport efficiency. This study provided evidence for the positive effects of His-Fe3O4 on S. cerevisiae cells and proposed a straightforward approach to enhance ethanol production in S. cerevisiae fermentation. The mediation of improved ethanol tolerance offers significant potential in the fermentation and bioenergy sectors.

Effect of Castor Oil on Bioprocess Parameters of Erythromycin Fermentation by Saccharopolyspora Erythraea

BACKGROUND

Increased economic competitiveness in the biopharmaceutical industry requires continuous improvement of bioprocesses. In this regard compositions of fermentation media have an important role in bioprocesses.

OBJECTIVES

The modification of the culture medium has proven effective in enhancing the yield and productivity of fermentation processes. The objective was to investigate the influence of castor oil as the main carbon source for Saccharopolyspora erythraea, on the yield of antibiotic fermentative production.

MATERIAL AND METHODS

The titer of erythromycin was evaluated in Saccharopolyspora erythraea cultures, containing various concentrations of castor oil, in comparison to the control culture containing rapeseed oil.

RESULTS

The results showed an enhancement in erythromycin production when 50 g.L^-1and 40 g.L^-1of castor oil were added to the fermentation culture instead of rapeseed oil, respectively. The highest amount of production was obtained on the eleventh day of fermentation time in all media.

CONCLUSION

Erythromycin production in the control medium was relatively less than that of the treatments, indicating that S. erythraea consumed castor oil as a rich alternative carbon source. The results show that castor oil was more suitable as a carbon source for erythromycin production than a medium containing rapeseed oil.

Effect of zinc oxide nanoparticle supplementation on the enhanced production of surfactin and iturin lipopeptides of endophytic Bacillus sp. Fcl1 and its ameliorated antifungal activity

BACKGROUND

Lipopeptides from the Bacillus spp. possess an excellent spectrum of antimicrobial properties which make them suitable candidates to be explored for the food, agricultural, pharmaceutical and biotechnological applications. As the low yield of the lipopeptides limits their applications, methods to enhance their production are highly significant.

RESULTS

In this study, extracts prepared from endophytic Bacillus sp. Fcl1 cultured in the presence of various supplements were screened for antifungal activity against Pythium aphanidermatum. From the results, the supplementation of carbon sources and zinc oxide nanoparticles (ZnONPs) was found to have an enhancement effect on the antifungal activity of Bacillus sp. Fcl1. Among these, the highest antifungal activity (73.2%) could be observed for the Fcl1 sample cultured with 5 mg L^-1 of ZnONP supplementation. The growth of Fcl1 in the presence of ZnONPs also indicated its compatibility with the nano-supplement in the concentration range used. By liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) analysis, the synthesis of increased numbers of lipopeptide surfactin derivatives could be identified from the extracts of Fcl1 prepared from the carbon sources and ZnONP-supplemented cultures. In addition to the surfactin derivatives, the presence of another lipopeptide iturin was also detected from the extracts of Fcl1 cultured with ZnONPs.

CONCLUSION

ZnONP supplementation was found to enhance antifungal activity and lipopeptide production in the Bacillus sp. Fcl1. The use of nanoparticles to enhance the antifungal mechanisms of Fcl1 as observed in the study provides novel insights to explore its applications for sustainable agricultural productivity.

Fe Nanoparticles Enhanced Surfactin Production in Bacillus amyloliquefaciens

Surfactin, as one of the most powerful biosurfactants, can be widely applied in agriculture, food, and pharmaceutics. However, low biosynthesis efficiency is the major obstacle in its commercialization. Here, we used nanoparticles to increase the surfactin production in Bacillus amyloliquefaciens MT45 through enhancing the secretion (the key step of surfactin biosynthesis). The results showed that the surfactin titer increased from 4.93 to 7.15 g/L in the flask and from 5.94 to 9.18 g/L in a 7 L bioreactor by adding 5 g/L Fe nanoparticles. They were the highest titers in the reported wild-type strain. Our results indicated that Fe nanoparticles enhanced the expression of genes involved in the biosynthesis of surfactin. Moreover, Fe nanoparticles increased the permeability of cell membranes, resulting in a more efficient secretion of surfactin. This study provides an efficient strategy for increasing the biosynthesis of microbial metabolites and provides new insights into the nanoparticles' impacts on microbes.