Effect of Quinoline on the Phospholipid Profile of Curvularia lunata and Its Microbial Detoxification

Synergistic Activity of Gloeophyllum striatum-Derived AgNPs with Ciprofloxacin and Gentamicin Against Human Pathogenic Bacteria

Silver nanoparticles (AgNPs) are used in a variety of different fields due to their excellent antimicrobial potential. Despite clear advantages, concerns about their toxicity have arisen, also concerning biogenic nanoparticles. Simultaneously, global healthcare is facing a problem of spreading antimicrobial resistance towards existing antibiotics. Using combined therapies involving AgNPs and antibiotics seems to be a promising solution to the above problems. The aim of this study was to evaluate the enhancement of the effectiveness of AgNPs, ciprofloxacin, and gentamicin against Staphylococcus aureus and Pseudomonas aeruginosa. The research involved the assessment of antimicrobial and antibiofilm-forming activities and the analysis of phospholipid and fatty acid profiles. Our results showed that combining the tested antimicrobials can enhance their activity against the tested bacterial strains. However, no effect was observed while mixing AgNPs with ciprofloxacin against P. aeruginosa. The most significant effect was obtained by combining 3.125 µg/mL of AgNPs with 0.125 µg/mL of gentamicin against S. aureus. It was also shown that the tested antimicrobials applied in combination exhibited an increased inhibitory activity towards bacterial biofilm formation by S. aureus. Lipidomic analysis revealed that under the influence of the tested antimicrobials, the properties of the cell membrane were altered in different ways depending on the bacterial strain.

One-pot bioconversion of fungal lipid to mycodiesel: a sustainable approach

The conversion of filamentous fungus-based feedstock into Biodiesel holds potential as a sustainable and eco-conscious method for producing alternative liquid fuels. This study examined the comparison of individual Fatty Acid Methyl Esters (FAME) of Aspergillus niger and Curvularia lunata with the consortium of both filamentous fungal cocktail Fatty acid methyl esters (cFAME), following a transesterification process that turned the fungal lipids into myco-based biodiesel productions. cFAME weighs 23.89 g and accumulates to 20.43 g of lipid yield, with 86% of cellular lipids; in contrast, A. niger weighs 12.65 g and pile up 9.5 g of lipid yield, with 75% of cellular lipid, also C. lunata exhibits 8.35 g of dry weight with 4.89 g of lipid concentration, with 59% of cellular lipids. A. niger was known to contain C16-C18 saturated and unsaturated fatty acids possess LAME (C18:2), OAFA (C18:1), and PAME (C16:0) were shown in high percentages accounted for 86.6% in A. niger. The results showed that PUFA was predominant over MUFA and SFA. C. lunata chiefly produces C16 and C18 fatty acids, which are considered favorable for combustion properties with oleic acid (C18:1), linoleic acid (C18:2), palmitic acid (C16:0), and stearic acid (C18:0), on the comparison. However, the FAME profile of C. lunata occupies only 39.07% of the biodiesel quality. Pentadecanoic acid, palmitic acid, palmitoleic acid, Oleic acid, Linolenic acid, Linoleic acis, and Hexanoic acid with the carbon range of C6:0 - C18:3 were observed in cFAME. Based on the biodiesel yield, cFAME scored 20.55%, whereas A. niger with 11.05 and C.lunata 2.45%, respectively. The presence of methyl esters containing various long-chain fatty acids indicates very effective biodiesel assets, as confirmed by GC-MS analysis, which evidenced ignition efficiency, among others. cFAMEs were impacted by high ignition efficiency with > 4 min. Consortium strategies seize attention in different dimensions and have been confirmed by their upregulation in their fatty acid profiles; in the future, the combination of high lipid holders among the fungal kingdom can be an alternative in myco-based biodiesel production.

Spatial specificity of metabolism regulation of abscisic acid-imposed seed germination inhibition in Korean pine (Pinus koraiensis sieb et zucc)

Introduction

Abscisic acid (ABA) can negatively regulate seed germination, but the mechanisms of ABA-mediated metabolism modulation are not well understood. Moreover, it remains unclear whether metabolic pathways vary with the different tissue parts of the embryo, such as the radicle, hypocotyl and cotyledon.

Methods

In this report, we performed the first comprehensive metabolome analysis of the radicle and hypocotyl + cotyledon in Pinus koraiensis seeds in response to ABA treatment during germination.

Results and discussion

Metabolome profiling showed that following ABA treatment, 67 significantly differentially accumulated metabolites in the embryo were closely associated with pyrimidine metabolism, phenylalanine metabolism, cysteine and methionine metabolism, galactose metabolism, terpenoid backbone biosynthesis, and glutathione metabolism. Meanwhile, 62 metabolites in the hypocotyl + cotyledon were primarily involved in glycerophospholipid metabolism and glycolysis/gluconeogenesis. We can conclude that ABA may inhibit Korean pine seed germination primarily by disrupting the biosynthesis of certain plant hormones mediated by cysteine and methionine metabolism and terpenoid backbone biosynthesis, as well as reducing the reactive oxygen species scavenging ability regulated by glutathione metabolism and shikimate pathway in radicle. ABA may strongly disrupt the structure and function of cellular membranes due to alterations in glycerophospholipid metabolism, and weaken glycolysis/gluconeogenesis in the hypocotyl + cotyledon, both of which are major contributors to ABA-mediated inhibition of seed germination. These results highlight that the spatial modulation of metabolic pathways in Pinus koraiensis seeds underlies the germination response to ABA.

Molecular Target Interactions of Quinoline Derivatives as Anticancer Agents: A Review

One of the leading causes of death worldwide is cancer, which poses substantial risks to both society and an individual's life. Cancer therapy is still challenging, despite developments in the field and continued research into cancer prevention. The search for novel anticancer active agents with a broader cytotoxicity range is therefore continuously ongoing. The benzene ring gets fused to a pyridine ring at two carbon atoms close to one another to form the double ring structure of the heterocyclic aromatic nitrogen molecule known as quinoline (1-azanaphthalene). Quinoline derivatives contain a wide range of pharmacological activities, including antitubercular, antifungal, antibacterial, and antimalarial properties. Quinoline derivatives have also been shown to have anticancer properties. There are many quinoline derivatives widely available as anticancer drugs that act via a variety of mechanisms on various molecular targets, such as inhibition of topoisomerase, inhibition of tyrosine kinases, inhibition of heat shock protein 90 (Hsp90), inhibition of histone deacetylases (HDACs), inhibition of cell cycle arrest and apoptosis, and inhibition of tubulin polymerization.

In vitro study of the ecotoxicological risk of methylisothiazolinone and chloroxylenol towards soil bacteria

Methylisothiazolinone (MIT) and chloroxylenol (PCMX) are popular disinfectants often used in personal care products (PCPs). The unregulated discharge of these micropollutants into the environment, as well as the use of sewage sludge as fertilizer and reclaimed water in agriculture, poses a serious threat to ecosystems. However, research into their ecotoxicity towards nontarget organisms is very limited. In the present study, for the first time, the ecotoxicity of biocides to Pseudomonas putida, Pseudomonas moorei, Sphingomonas mali, and Bacillus subtilis was examined. The toxicity of MIT and PCMX was evaluated using the microdilution method, and their influence on the viability of bacterial cells was investigated by the AlamarBlue® test. The ability of the tested bacteria to form biofilms was examined by a microtiter plate assay. Intracellular reactive oxygen species (ROS) production was measured with CM-H2DCFDA. The effect of MIT and PCMX on phytohormone indole-3-acetic acid (IAA) production was determined by spectrophotometry and LC‒MS/MS techniques. The permeability of bacterial cell membranes was studied using the SYTOX Green assay. Changes in the phospholipid profile were analysed using LC‒MS/MS. The minimal inhibitory concentrations (MICs) values ranged from 3.907 to 15.625 mg L^-1 for MIT and 62.5 to 250 mg L^-1 for PCMX, indicating that MIT was more toxic. With increasing concentrations of MIT and PCMX, the cell viability, biofilm formation ability and phytohormone synthesis were maximally inhibited. Moreover, the growth of bacterial cell membrane permeability and a significantly increased content of ROS were observed, indicating that the exposure caused serious oxidative stress and homeostasis disorders. Additionally, modifications in the phospholipid profile were observed in response to the presence of sublethal concentrations of the chemicals. These results prove that the environmental threat posed by MIT and PCMX must be carefully monitored, especially as their use in PCPs is still growing.

Microplastic-Induced Oxidative Stress in Metolachlor-Degrading Filamentous Fungus Trichoderma harzianum

While there has been intensive research on the influence of microplastics (MPs) on aquatic organisms and humans, their effect on microorganisms is relatively little-known. The present study describes the response of the Trichoderma harzianum strain to low-density polyethylene (LDPE) microparticles. MPs, either separately or with metolachlor (MET), were added to the cultures. Initially, MP was not found to have a negative effect on fungal growth and MET degradation. After 72 h of cultivation, the content of fungal biomass in samples with MPs was almost three times higher than that in the cultures without MPs. Additionally, a 75% degradation of the initial MET was observed. However, due to the qualitative and quantitative changes in individual classes of phospholipids, cell membrane permeability was increased. Additionally, MPs induced the overproduction of reactive oxygen species. The activity of superoxide dismutase and catalase was also increased in response to MPs. Despite these defense mechanisms, there was enhanced lipid peroxidation in the cultures containing the LDPE microparticles. The results of the study may fill the knowledge gap on the influence of MPs on filamentous fungi. The findings will be helpful in future research on the biodegradation of contaminants coexisting with MPs in soil.

Integrated Lipidomic and Transcriptomic Analysis Reveals Phospholipid Changes in Somatic Embryos of Picea asperata in Response to Partial Desiccation

Partial desiccation treatment (PDT) is an effective technology for promoting the germination and conversion of conifer somatic embryos (SEs). PDT, as a drought stress, induces intensive physiological responses in phospholipid metabolism, which are not well understood in the conifer SEs. Here, we integrated lipidomics, transcriptomics and proteomics analyses to reveal the molecular basis of lipid remodeling under PDT in Picea asperata SEs. Among the 82 lipid molecular species determined by mass spectrometry, phosphatidic acid (PA) had a significant effect after PDT and was the most critical lipid in the response to PDT. The transcriptomics results showed that multiple transcripts in the glycerolipid and glycerophospholipid metabolism pathways were differentially expressed, and these included five PLDα1 transcripts that catalyze the conversion of phosphatidylcholine (PC) to PA. Furthermore, the enzyme activity of this phospholipase D (PLD) was significantly enhanced in response to PDT, and PDT also significantly increased the protein level of PLDα1 (MA_10436582g0020). In addition, PA is a key factor in gibberellin, abscisic acid and ethylene signal transduction. One GDI1, one DELLA, three ABI1s, two SnRK2s, one CTR and 12 ERFs showed significantly differential expression between SEs before and after PDT in this study. Our data suggest that the observed increases in the PA contents might result from the activation of PLDα by PDT. PA not only affects the physical and chemical properties of the cell membrane but also participates in plant hormone signal transduction. Our work provides novel insight into the molecular mechanism through which PDT promotes the germination of SEs of coniferous tree species and fills the gap in the understanding of the mechanism of somatic embryo lipid remodeling in response to PDT.