-
Organic Letters Jun 2024One rare stephacidin-asperochratide hybrid, stephaochratidin A (), was isolated from the deep-sea-derived MCCC 3A00521. The relative structure of was determined by...
One rare stephacidin-asperochratide hybrid, stephaochratidin A (), was isolated from the deep-sea-derived MCCC 3A00521. The relative structure of was determined by comprehensive analyses of its 1D and 2D NMR data as well as HRESIMS data. And the absolute configuration was unambiguously assigned by ECD calculations and the X-ray single-crystal diffraction analysis. Plausible biosynthetic pathway of was proposed. Stephaochratidin A () exhibited significant ferroptosis inhibitory activity with the EC value of 15.4 μM by downregulating HMOX-1 expression and lipid peroxidation.
PubMed: 38912656
DOI: 10.1021/acs.orglett.4c01745 -
Frontiers in Pharmacology 2024Lung cancer is the most commonly diagnosed and the main cause of cancer death, usually related to cigarette smoking. Furthermore, the microbiota of people exposed to...
INTRODUCTION
Lung cancer is the most commonly diagnosed and the main cause of cancer death, usually related to cigarette smoking. Furthermore, the microbiota of people exposed to cigarette smoke can be modified, making it difficult to eliminate opportunistic microorganisms. The leaves of are a by-product of fruit production and, to date, there have been no studies addressing the antiproliferative, anti-inflammatory, and antimicrobial activities.
OBJECTIVE
Investigate the antimicrobial, Nitric Oxide (NO)-production inhibition, and antiproliferative activities of the essential oil from leaves and its possible effect on the treatment and prevention of damage caused by tobacco.
METHODS
The essential oil (EO) was obtained by hydrodistillation (3 h). Its chemical composition was investigated by GC-MS. It was proposed to investigate antiproliferative activity against human tumor cell lines, namely, breast adenocarcinoma (MCF-7), lung (NCI-H460), cervical (HeLa), and hepatocellular (HepG2) carcinomas. A non-tumor primary culture from pig liver (PLP2) was also tested. The EO capacity to inhibit nitric oxide (NO) production was evaluated by a lipopolysaccharide stimulated murine macrophage cell line. Antibacterial and antifungal activities against opportunistic pathogens were investigated against seven strains of bacteria and eight fungi.
RESULTS
The results indicated the presence of 23 compounds in the essential oil, the majority were spathulenol (45.63%) and β-caryophyllene oxide (12.72%). Leaf EO provided 50% inhibition of nitric oxide production at a concentration of 92.04 µg mL. The EO also demonstrated antiproliferative activity against all human tumor cell lines studied, with GI50 values comprised between 270.86 and 337.25 µg mL. The essential oil showed antimicrobial potential against the bacteria monocytogenes (Murray et al.) Pirie (NCTC 7973) and ATCC 13311 (MIC 1870 µg mL) and fungi ATCC 11730, ATCC 12066, ATCC 90288, var. cyclopium (Westling) Samson, Stolk & Hadlok (food isolate) (MIC 1870 µg mL) and Pers. IAM 5061 (1,400 µg mL).
CONCLUSION
The demonstrated anti-inflammatory, antiproliferative, and antimicrobial activities in the leaves of can add value to the production chain of this plant, being a possible option for preventing and combating cancer, including lung cancer.
PubMed: 38910894
DOI: 10.3389/fphar.2024.1415659 -
Cellular and Molecular Life Sciences :... May 2024Aspergillus ochraceus is the traditional ochratoxin A (OTA)-producing fungus with density-dependent behaviors, which is known as quorum sensing (QS) that is mediated by...
Aspergillus ochraceus is the traditional ochratoxin A (OTA)-producing fungus with density-dependent behaviors, which is known as quorum sensing (QS) that is mediated by signaling molecules. Individual cells trend to adapt environmental changes in a "whole" flora through communications, allowing fungus to occupy an important ecological niche. Signals perception, transmission, and feedback are all rely on a signal network that constituted by membrane receptors and intracellular effectors. However, the interference of density information in signal transduction, which regulates most life activities of Aspergillus, have yet to be elucidated. Here we show that the G protein-coupled receptor (GPCR) to cAMP pathway is responsible for transmitting density information, and regulates the key point in life cycle of A. ochraceus. Firstly, the quorum sensing phenomenon of A. ochraceus is confirmed, and identified the density threshold is 10 spores/mL, which represents the low density that produces the most OTA in a series quorum density. Moreover, the GprC that classified as sugar sensor, and intracellular adenylate cyclase (AcyA)-cAMP-PKA pathway that in response to ligands glucose and HODEs are verified. Furthermore, GprC and AcyA regulate the primary metabolism as well as secondary metabolism, and further affects the growth of A. ochraceus during the entire life cycle. These studies highlight a crucial G protein signaling pathway for cell communication that is mediated by carbohydrate and oxylipins, and clarified a comprehensive effect of fungal development, which include the direct gene regulation and indirect substrate or energy supply. Our work revealed more signal molecules that mediated density information and connected effects on important adaptive behaviors of Aspergillus ochraceus, hoping to achieve comprehensive prevention and control of mycotoxin pollution from interrupting cell communication.
Topics: Quorum Sensing; Aspergillus ochraceus; Signal Transduction; Glucose; Cyclic AMP; Adenylyl Cyclases; Receptors, G-Protein-Coupled; Fungal Proteins; Ochratoxins
PubMed: 38806811
DOI: 10.1007/s00018-024-05160-z -
EFSA Journal. European Food Safety... Apr 2024The food enzyme oryzin (EC 3.4.21.63) is produced with the non-genetically modified strain AE-P by Amano Enzyme Inc. The food enzyme was considered free from viable...
The food enzyme oryzin (EC 3.4.21.63) is produced with the non-genetically modified strain AE-P by Amano Enzyme Inc. The food enzyme was considered free from viable cells of the production organism. It is intended to be used in nine food manufacturing processes. The dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.1 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1862 mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 18,620. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and 31 matches were found, including one food allergen (melon). The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme, particularly in individuals sensitised to melon, cannot be excluded, but would not exceed the risk from consumption of this food. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.
PubMed: 38634008
DOI: 10.2903/j.efsa.2024.8713 -
Heliyon Apr 2024Marine fungi represent an important proportion of the microbial diversity in the oceans. They are attractive candidates for biotechnological purposes and industrial...
Marine fungi represent an important proportion of the microbial diversity in the oceans. They are attractive candidates for biotechnological purposes and industrial applications. Despite an increasing interest in mycology, marine fungi associated with sponges and algae have been poorly studied in Mauritius. The objectives of this study were to: 1) use multigene phylogenetic analyses to identify isolated marine fungi; 2) determine the differences in the antimicrobial and antioxidant properties of the fungal extracts; and 3) assess their enzyme activities and dye decolorization potential. Five fungal isolates , , and sp. were identified based on phylogenetic analyses. There was no significant difference in the antimicrobial properties of the liquid and solid media extracts unlike the antioxidant properties (p < 0.05). The solid media extract of (F2-SF) had a minimum inhibitory concentration of 0.156 mg/ml against while (F25-SF) had a minimum inhibitory concentration of 0.313 and 2.5 mg/ml against and . The solid media extract of sp. (F34-SF) had a minimum inhibitory concentration of 0.195 and 1.563 mg/ml against , and . An IC of 78.92 ± 4.71 μg/ml in the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, ferric reducing antioxidant power (FRAP) value of 11.17 ± 0.20 mM Fe/g dry weight extract (DWE) and total phenolic content 360.35 ± 10.31 mg GAE/g DWE was obtained with the solid media extract of (F2-SF). (F25-SF) and sp. (F34-SF) solid media extracts showed lower IC values in the DPPH assay and higher total phenolic content as compared to the liquid media extracts. was a good producer of the enzymes DNAse and lipase and had maximum percentage dye decolorization of 79.40 ± 17.72% on Congo red. An enzymatic index ≥ 2 was found for the DNAse and lipase and the maximum percentage dye decolorization of 87.18 ± 3.80% was observed with on Methylene blue. Regarding sp., it was a moderate producer of the three enzymes amylase, DNAse and protease and had a maximum dye decolorization potential of 56.29 ± 6.51% on Crystal violet. This study demonstrates that Mauritian marine fungi possess good bioactive properties, enzymatic and dye decolorization potentials, that can potentially be considered for use in pharmaceutical and industrial applications.
PubMed: 38623192
DOI: 10.1016/j.heliyon.2024.e28955 -
Archives of Toxicology Jul 2024Ochratoxin A (OTA) is a widespread food toxin produced by Aspergillus ochraceus and other molds. In this study, we developed and established acute OTA toxicity...
Ochratoxin A (OTA) is a widespread food toxin produced by Aspergillus ochraceus and other molds. In this study, we developed and established acute OTA toxicity conditions in mice, which received daily oral doses of OTA between 0.5 up to 8 mg/kg body weight up to 7 days and were subjected to histological and biochemical analysis to characterize renal and hepatic damage. Oral administration of OTA for 7 days resulted in loss of body weight in a dose-dependent manner and increased the levels of serum biomarkers of hepatic and renal damage. The kidney was more sensitive to OTA-induced damage than the liver. In addition to necrosis, OTA induced hepatic and renal apoptosis in dose- and time-dependent manners. Especially, a high dose of OTA (8 mg/kg body weight) administered for 7 days led to necroptosis in both liver and kidney tissues. OTA dose-dependently increased the oxidative stress levels, including lipid peroxidation, in the liver and kidneys. OTA disrupted mitochondrial dynamics and structure in hepatic and renal cells, leading to the dysregulation of mitochondrial homeostasis. OTA increased transferrin receptor 1 and decreased glutathione peroxidase 4 levels in a dose- and time-dependent manner. These results suggest the induction of ferroptosis. Collectively, this study highlighted the characteristics of acute OTA-induced hepatic and renal toxicity in mice in terms of oxidative stress, mitochondrial damage, and multiple cell death mechanisms, including necroptosis and ferroptosis.
Topics: Animals; Ochratoxins; Oxidative Stress; Kidney; Liver; Mice; Male; Mitochondria; Chemical and Drug Induced Liver Injury; Dose-Response Relationship, Drug; Apoptosis; Lipid Peroxidation; Ferroptosis; Necroptosis
PubMed: 38546835
DOI: 10.1007/s00204-024-03732-3 -
Antibiotics (Basel, Switzerland) Feb 2024Nowadays, unprecedented health challenges are urging novel solutions to address antimicrobial resistance as multidrug-resistant strains of bacteria, yeasts and moulds...
Nowadays, unprecedented health challenges are urging novel solutions to address antimicrobial resistance as multidrug-resistant strains of bacteria, yeasts and moulds are emerging. Such microorganisms can cause food and feed spoilage, food poisoning and even more severe diseases, resulting in human death. In order to overcome this phenomenon, it is essential to identify novel antimicrobials that are naturally occurring, biologically effective and increasingly safe for human use. The development of gemmotherapy extracts (GTEs) using plant parts such as buds and young shoots has emerged as a novel approach to treat/prevent human conditions due to their associated antidiabetic, anti-inflammatory and/or antimicrobial properties that all require careful evaluations. Seven GTEs obtained from plant species like the olive ( L.), almond ( L.), black mulberry ( L.), walnut ( L.), blackberry ( L.), blackcurrant ( L.) and bilberry ( L.) were tested for their antimicrobial efficiency via agar diffusion and microbroth dilution methods. The antimicrobial activity was assessed for eight bacterial (, , subsp. , , , , and ), five moulds (, , , , ) and one yeast strain (). The agar diffusion method revealed the blackberry GTE as the most effective since it inhibited the growth of three bacterial, four moulds and one yeast species, having considered the total number of affected microorganism species. Next to the blackberry, the olive GTE appeared to be the second most efficient, suppressing five bacterial strains but no moulds or yeasts. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were then determined for each GTE and the microorganisms tested. Noticeably, the olive GTE appeared to feature the strongest bacteriostatic and bactericidal outcome, displaying specificity for , and . The other GTEs, such as blueberry, walnut, black mulberry and almond (the list indicates relative strength), were more effective at suppressing microbial growth than inducing microbial death. However, some species specificities were also evident, while the blackcurrant GTE had no significant antimicrobial activity. Having seen the antimicrobial properties of the analysed GTEs, especially the olive and black mulberry GTEs, these could be envisioned as potential antimicrobials that might enhance antibiotic therapies efficiency, while the blackberry GTE would act as an antifungal agent. Some of the GTE mixtures analysed have shown interesting antimicrobial synergies, and all the antimicrobial effects observed argue for extending these studies to include pathological microorganisms.
PubMed: 38391567
DOI: 10.3390/antibiotics13020181 -
Toxins Dec 2023In the context of the mysterious Balkan endemic nephropathy of the 1900s, and the discovery in the 1960s of the potent mycotoxin ochratoxin A, experimental research... (Review)
Review
In the context of the mysterious Balkan endemic nephropathy of the 1900s, and the discovery in the 1960s of the potent mycotoxin ochratoxin A, experimental research projects sought to explore any inter-relationship. Experimental lifetime administration of the toxin to male rats had revealed renal DNA adducts with the toxin, correlated with renal tumours, confirmation of which required molecular evidence. Consequently, production of C-ochratoxin A of a high specific radioactivity was required, practical biosynthetic detail of which had not previously been published. A fermentation study of was carried out during 2002 for a European project, to select for the production of high-quality C-ochratoxin A, necessarily exploring for the maximum diversion of C-sodium acetate into the pentaketide portion of mycotoxin. Experimentation necessarily had to optimise the competitive context of fungal growth dynamics and addition of the biosynthetic precursor in the early days of shaken-flask fermentation before adding the radiolabelled precursor. From optimal fermentation, 50 mg of the C ochratoxin A was supplied within a European project for DNA adduct experimentation, but that proved negative as subsequently published. Experimental description of the radiolabelled ochratoxin A production was later made in a doctoral thesis, but is first publicised here. Further review of the literature reveals an explanation for the published failure to confirm rat DNA/ochratoxin A adduct formation, for which further experimentation is now recommended.
Topics: Male; Animals; Rats; Aspergillus ochraceus; Fermentation; Balkan Nephropathy; Mycotoxins; Ochratoxins
PubMed: 38251225
DOI: 10.3390/toxins16010008 -
Waste Management (New York, N.Y.) Mar 2024Exposure to high levels of microbial contaminants during waste disposal leads to the development of various diseases, including respiratory symptoms and gastrointestinal...
Exposure to high levels of microbial contaminants during waste disposal leads to the development of various diseases, including respiratory symptoms and gastrointestinal infections. In this study, the emissions of airborne bacteria and fungi during the process of sludge bio-drying were investigated. The recorded emission levels of airborne bacteria and fungi were 2398 ± 1307 CFU/m and 1963 ± 468 CFU/m, respectively. Viable bacteria were sized between 1.1 and 3.3 μm, while fungal particles were concentrated between 2.1 and 4.7 μm. High-throughput sequencing was used to conduct a microbial population assay, and correlation analysis was performed to estimate the relationship between key factors and bioaerosol emissions. The main bacteria identified were Bacillus sp., Lysinibacillus sp. YS11, unclassified Enterobacteriaceae, Brevundimonas olei, and Achromobacter sp.; the primary types of fungi were Aspergillus ochraceus, Gibberella intricans, Fusarium concentricum, Aspergillus qinqixianii, and Alternaria sp.; and the dominant opportunistic pathogens were Bacillus anthracis and Aspergillus ochraceus. At lower moisture and temperature levels, airborne bacterial concentrations were higher, especially the release of fine particles. In addition, moisture content had a significant impact on the microbial population in bioaerosols. This study provides insights into strategies for controlling bioaerosols in the exhaust gases of the sludge bio-drying process.
Topics: Sewage; Air Microbiology; Bacteria; Bacillus; Aerosols; Fungi; Environmental Monitoring
PubMed: 38237405
DOI: 10.1016/j.wasman.2024.01.009 -
Molecules (Basel, Switzerland) Dec 2023Biotransformation of ursonic acid () by two fungal strains CGMCC 3.5324 and CGMCC 3.407 yielded thirteen new compounds (, , -, and -), along with five recognized ones....
Biotransformation of ursonic acid () by two fungal strains CGMCC 3.5324 and CGMCC 3.407 yielded thirteen new compounds (, , -, and -), along with five recognized ones. The structural details of new compounds were determined through spectroscopic examination (NMR, IR, and HR-MS) and X-ray crystallography. Various modifications, including hydroxylation, epoxidation, lactonization, oxygen introduction, and transmethylation, were identified on the ursane core. Additionally, the anti-neuroinflammatory efficacy of these derivatives was assessed on BV-2 cells affected by lipopolysaccharides. It was observed that certain methoxylated and epoxylated derivatives (, , and ) showcased enhanced suppressive capabilities, boasting IC values of 8.2, 6.9, and 5.3 μM. Such ursonic acid derivatives might emerge as potential primary molecules in addressing neurodegenerative diseases.
Topics: Aspergillus ochraceus; Aspergillus oryzae; Crystallography, X-Ray; Biotransformation
PubMed: 38138433
DOI: 10.3390/molecules28247943