BMC Biotechnology最新文献

This study aims to evaluate the effectiveness of a new alternative biofungicidal product in controlling the fungal disease agent, Fusarium oxysporum f. sp. cepae, which causes considerable losses during onion storage. In the first stage of this study, silver nanoparticles derived from the microorganism (Phoma herbarum) were biosynthesized using the green synthesis method in nanotechnology. Characterisation tests of the nano product, which was synthesized through the biosynthesis process, confirmed that it is a silver-based nano product with size dimensions ranging from 4 to 40 nm. In the second phase of the study, the fungicidal efficacy of the synthesized silver nanoparticle product, at concentrations ranging from 2.5 to 500 ppm, was investigated against pathogenic fungi. Its effectiveness was evaluated under both in vitro and in vivo conditions. In the in vitro study conducted in petri dishes, the highest mycelial growth, 87.66 ± 0.57 mm, was observed in the control group. Following the application of 2.5 and 5 ppm silver nanoparticles, the mycelium diameter measured 86.66 ± 1.15 mm. However, as the concentration of silver nanoparticles increased, a significant reduction in mycelial growth was observed. At 200 ppm, the mycelial diameter decreased to 10.66 ± 1.15 mm; at 500 ppm, no mycelial growth was observed. In the in vivo study conducted on onion bulbs, the fungicidal activity of silver nanoparticles was evaluated by measuring the disease inhibition rates after the application of silver nanoparticles on the bulbs. When disease inhibition rates are compared in onion bulbs, the dose-dependent rot diameters are as follows: positive control(50.20 ± 0.20 mm); 10 ppm (34.60 ± 0.50 mm); 25 ppm (27.60 ± 0.30 mm); 50 ppm (19.00 ± 0.38); 100 ppm (12.00 ± 0.40); 200 ppm (6.80 ± 0.31 mm) and 500 ppm (1.20 ± 0.17 mm). In addition to these results, different concentrations of silver nanoparticles demonstrated a dose-dependent reduction in disease incidence, ranging from 28.89% to 94.42%. When evaluated collectively, the results indicated that silver nanoparticles synthesized through the green synthesis method exhibited varying degrees of fungicidal activity under both in vitro and in vivo conditions, with effectiveness dependent on the concentration applied. Consequently, the synthesized silver nanoparticles product has demonstrated considerable potential as an alternative solution for effectively managing Fusarium oxysporum f. sp. cepae a significant threat to stored onion bulbs.

Background: Fruit peels as a lignocellulosic biomass are rich in sugars and nutrients, thus making them favorable medium for yeast growth and various materials production. This study showed the potential of fuit peels hydrolysate (FPH) as a substrate for single-cell protein (SCP) and bioethanol production, depending on substrate concentration, pH, oxygen availability.

Results: The highest specific growth rate (0.50 ± 0.01 h^- 1) was observed at pH 6.5 in non-diluted hydrolysates, which corresponds to ~ 250.0 g L^- 1 carbohydrates and 0.2 g L^- 1 total nitrogen concentration. The maximal protein production yield (~ 50% by dry weight) was recorded during 24 h cultivation of S. cerevisiae ATCC 13,007 under oxygen-limited conditions at pH 6.5, while the maximal ethanol production (109.00 ± 4.00 g L^- 1) was observed at 6 h for S. cerevisiae ATCC 9804 and ATCC 13,007 starins under aerobic conditions. The maximal fermentation efficiency (~ 99%) was observed at 24 h cultivation of S. cerevisiae ATCC 13,007 in 2-fold diluted hydrolysate under oxygen-limited conditions at pH 6.5, while the same strain exhibited the highest carbon conversion efficiency (CCE) (~ 56%) during aerobic cultivation in 2-fold diluted hydrolysate at pH 3.0.

Conclusion: Thus, FPH can serve as a favorable substrate for SCP and bioethanol production using S. cerevisiae strains ATCC 13,007 and ATCC 9804. Nitrogen supplementation and combination with fruit and vegetable processing industries could further enhance SCP production and process efficiency which aligns with circular economic strategy.

Background: Nicotine exhibits positive heterosis, and through its utilization, new tobacco varieties with ideal nicotine content have been bred. However, the potential mechanism underlying the increased transport and nicotine accumulation capacity in hybrids remain poorly understood.

Results: The purpose of this study was to reveal the regulatory role of the key gene NtGSTU10, which was identified during the early stages of nicotine heterosis. NtGSTU10-over expression lines were created through genetic transformation, and the nicotinic content, transport coefficient, and heterosis of NtGSTU10-over expression lines and wild-type tobacco plants were compared. The results suggested that the nicotine content in the leaves of V×OB7 (The over expression hybrids were produced by crossing Va116 as the female parent with OB7 as the male parent.) and V×OB12 (The over expression hybrids were produced by crossing Va116 as the female parent with OB12 as the male parent.) was significantly higher than that of the wild-type hybrid (V×B). Compared to the V×B, the nicotine transport coefficients of V×OB7 and V×OB12 were significantly increased by 39.50% and 40.67%, respectively; and nicotine heterosis was significantly increased by 120.07% and 127.59%, respectively. Further analysis showed that overexpression of the NtGSTU10 gene could result in up-regulated expression of genes related to nicotine synthesis (AOC, QS, ODC, and PAO) and transport (ABCB1, ABCC1, and ABCC2), as well as down-regulation of negative regulatory factors (ERF1, ETR, and JAZ).

Conclusions: The results indicated that overexpression of the NtGSTU10 gene promotes the synthesis and transport metabolism of nicotine in tobacco, positively contributing to increased nicotine content in hybrids. The research findings provide a molecular basis for regulating the nicotine transport and accumulation in hybrids, and also provide genetic resources for the targeted cultivation of new tobacco varieties with suitable nicotine content.