Dimethyl phthalate destroys the cell membrane structural integrity of Pseudomonas fluorescens

Antifungal activity of chalcone derivatives containing 1,2,3,4-tetrahydroquinoline and studies on them as potential SDH inhibitors

BACKGROUND

A large number of pathogenic fungi have caused serious damage to the global crop yield, and drug resistance is always a topic that cannot be avoided for traditional fungicides. Therefore, finding efficient, green, and low-toxic fungicides is our primary task, which brings opportunities for the development of natural product green pesticides.

RESULTS

Twenty chalcone derivatives containing 1,2,3,4-tetrahydroquinoline were designed and synthesized, and the compounds were tested for their fungicidal effects against eight plant pathogenic fungi in vitro. The results demonstrate that the original splicing did not have fungicidal activity, so a piperazine fragment was introduced; the test results revealed that H1-H10 all had good antifungal activity. Among them, H4 showed the highest inhibitory activity against Phytophthora capsici (Pc) with a median effect concentration (EC50) value of 5.2 μg/mL, which was higher than that of the control drugs Azoxystrobin (EC50 = 80.2 μg/mL) and Fluopyram (EC50 = 146.8 μg/mL). After the study, it was demonstrated that H4 mainly acted on the cell membrane against Phytophthora capsici and inhibited the activity of the marker enzyme of mitochondria (SDH) in the fungus.

CONCLUSION

H4 has significant resistance to Phytophthora capsici and also plays a significant role in inhibiting SDH activity, providing a new direction for the development of green pesticides. © 2024 Society of Chemical Industry.

Impacts of microplastic decomposition using heat-activated persulfate on antibiotic adsorption and environmental toxicity

The objective of this study was to determine microplastic-antibiotic interaction by examining how heat-activated persulfate decomposed polyamide adsorbed antibiotics and explored the environmental consequences of treated water. Sulfate radicals roughened the microplastic surfaces, significantly enhancing the adsorption capacity of polyamide. The kinetic and isotherm studies provided confirmation that electrostatic interactions were the primary mechanisms, with a minor contribution from H-bonding, highlighting that antibiotic adsorption was prone to occur, especially on the aged surface. Thermodynamic data indicated that the process was spontaneous and exothermic. The results showed significant negative effects of treated water on seed germination, copepod survival, and cell lines at only a higher concentration, due to a decrease in pH and the potential presence of polymer degradates. Our findings revealed the significant impact of decomposed polyamide on the antibiotic adsorption and offered insight into the potential harm that microplastic-treated water might cause to aquatic and marine ecosystems.

Is aromatic plants environmental health engineering (APEHE) a leverage point of the earth system?

It is important to note that every ecological niche in an ecosystem is significant. This study aims to assess the importance of medicinal and aromatic plants (MAPs) in the ecosystem from multiple perspectives. A primary model of Aromatic Plants Environmental Health Engineering (APEHE) has been designed and constructed. The APEHE system was used to collect aerosol compounds, and it was experimentally verified that these compounds have the potential to impact human health by binding to AKT1 as the primary target, and MMP9 and TLR4 as secondary targets. These compounds may indirectly affect human immunity by reversing drug resistance in drug-resistant bacteria in the nasal cavity. This is mainly achieved through combined mutations in sdhA, scrA, and PEP. Our findings are based on Network pharmacology and molecular binding, drug-resistance rescue experiments, as well as combined transcriptomics and metabolomics experiments. It is suggested that APEHE may have direct or indirect effects on human health. We demonstrate APEHE's numerous potential benefits, such as attenuation and elimination of airborne microorganisms in the environment, enhancing carbon and nitrogen storage in terrestrial ecosystems, promoting the formation of low-level clouds and strengthening the virtuous cycle of Earth's ecosystems. APEHE also supports the development of transdisciplinary technologies, including terpene energy production. It facilitates the creation of a sustainable circular economy and provides additional economic advantages through urban optimisation, as well as fresh insights into areas such as the habitability of other planets. APEHE has the potential to serve as a leverage point for the Earth system. We have created a new research direction.

Engineering the synthesis of unsaturated fatty acids by introducing desaturase improved the stress tolerance of yeast

BACKGROUND

Yeast is often used to build cell factories to produce various chemicals or nutrient substances, which means the yeast has to encounter stressful environments. Previous research reported that unsaturated fatty acids were closely related to yeast stress resistance. Engineering unsaturated fatty acids may be a viable strategy for enhancing the stress resistance of cells.

RESULTS

In this study, two desaturase genes, OLE1 and FAD2 from Z. rouxii, were overexpressed in S. cerevisiae to determine how unsaturated fatty acids affect cellular stress tolerance of cells. After cloning and plasmid recombination, the recombinant S. cerevisiae cells were constructed. Analysis of membrane fatty acid contents revealed that the recombinant S. cerevisiae with overexpression of OLE1 and FAD2 genes contained higher levels of fatty acids C16:1 (2.77 times), C18:1 (1.51 times) and C18:2 (4.15 times) than the wild-type S. cerevisiae pY15TEF1. In addition, recombinant S. cerevisiae cells were more resistant to multiple stresses, and exhibited improved membrane functionality, including membrane fluidity and integrity.

CONCLUSION

These findings demonstrated that strengthening the expression of desaturases was beneficial to stress tolerance. Overall, this study may provide a suitable means to build a cell factory of industrial yeast cells with high tolerance during biological manufacturing. © 2023 Society of Chemical Industry.