Penicillic Acid Research Articles

The Presence of Some Minor Aspergillus and Penicillium Unregulated Mycotoxins in Main Cereals Cultivated in Albania

(1) Background: Food and feed safety legislation does not concern all the mycotoxins generated by Penicillium and Aspergillus spp. Certain mycotoxins, including mycophenolic acid (MPA), cyclopiazonic acid (CPA), penicillic acid (PA), roquefortine C (ROQ C), and gliotoxin (GLI), are regarded as having lower toxicity levels, and hence are not included in food and feed legislation. It is obvious that xenobiotics, including mycotoxins, exert synergistic harmful health effects on human and animal when exposed through food and feed. (2) Methods: The presence of these substances in maize and wheat grown in Albania across two consecutive harvesting seasons was investigated by liquid chromatography and mass spectrometry (LC-MS/MS). (3) Results: The findings indicated the presence of these mycotoxins in maize grain but not in wheat grain. In the 2014 season, they exhibited a higher contamination incidence than in the 2015 season. The most commonly detected mycotoxin was MPA, followed by CPA and ROQ C toxin, while PA and GLI were not detected. The MPA revealed a concentration range of 72.9–3447 μg/kg, with a mean value of 1064 μg/kg. Mycophenolic acid was detected in the maize samples collected during the 2015 season. (4) Conclusions: These findings suggest that focusing the investigation only on “controlled” mycotoxins will not produce a proper risk assessment and may not adequately address the possible harmful impacts of mycotoxins on human and animal health due to mycotoxins’ co-occurrence.

Determination of mycotoxin content, microbiological and physicochemical properties and sensory quality during ripening of Erzincan Tulum cheese produced with strain Penicillium roqueforti 41

Erzincan Tulum cheeses were produced from raw sheep milk with traditional homemade rennet as the uninoculated (control) and inoculated with Penicillium roqueforti 41. The cheese was ripened at 4 ± 1 °C for 120 days. All the cheese samples were drilled to achieve oxygenation during the last two stages of the ripening period. The microbiological and physicochemical properties, presence of mycotoxins and sensory characteristics of the Tulum cheeses, which were filled by pressing into the goat skin bags (called tulums) and plastic barrels, were investigated during the ripening period. The coliform bacteria count of the cheeses decreased, and Staphylococcus aureus was not detected (< 2 log CFU/g) in the cheeses. The lowest and highest levels of penicillic acid (PA), roquefortine C and mycophenolic acid (MPA) in the cheeses during ripening ranged from 0.01–0.08, 0.01–0.06 and ND–0.06 mg/kg, respectively. Patulin was not detected. It was concluded that the Tulum cheeses were safer in terms of the amount of patulin, PA, roquefortine C, and MPA than those previously reported in the literature. P. roqueforti counts considerably increased during the last two stages of ripening. A new variety of credible mouldy cheese can be manufactured using the P. roqueforti 41 strain. However, a drilling process is needed to provide oxygen for P. roqueforti 41 growth during ripening.

Determination of penicillic acid in cereals by solid-phase extraction and gas chromatography-tandem mass spectrometry

A gas chromatography-tandem mass spectrometry (GC−MS/MS) method was established for accurately determining penicillic acid in cereals. The cereal samples were extracted using acidified acetonitrile, purified by solid-phase extraction, and derived using N,O-bis(trimethylsilyl) acetamide for GC−MS/MS analysis. Recovery experiments were conducted with low, medium, and high concentrations. The recovery rates were 72.1%–89.8%, the relative standard deviations were less than 8.6%, and the limit of quantification was 20 μg/kg. The established method was rapid, efficient, sensitive, and specific, meeting the requirements for the determination of penicillic acid in cereals. The method exhibits high sensitivity, accurate results, and stable recovery, making it suitable for detecting penicillic acid residues in cereals.

The regulation effect of preventing soil nitrogen loss using microbial quorum sensing inhibitors

Preventing soil nitrogen (N) losses driven by microbial nitrification and denitrification contributes to improving global environmental concerns caused by NO3−-N leaching and N2O emission. Quorum sensing (QS) signals regulate nitrification and denitrification of N-cycling bacteria in pure culture and water treatment systems, and mediate the composition of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in activated sludge. However, whether disrupting QS could prevent soil N losses remains unclear. This study explored the feasibility of applying quorum sensing inhibitors (QSIs) as an innovative strategy to reduce N losses from agricultural soils. The two QSIs, penicillic acid and 4-iodo-N-[(3S)-tetrahydro-2-oxo-3-furanyl]-benzeneacetamide (4-iodo PHL), were more effective in reducing N losses than traditional inhibitors, including N-(n-butyl) thiophosphoric triamide and 3,4-dimethylpyrazole phosphate. After 36 days of aerobic incubation, penicillic acid and 4-iodo PHL inhibited nitrification by 39% and 68%, respectively. The inhibitory effects are attributed to the fact that 4-iodo PHL decreased the abundance of archaeal and bacterial amoA genes, as well as the relative abundance of Candidatus Nitrocosmicus (AOA), Candidatus Nitrososphaera (AOA), and Nitrospira (nitrite-oxidizing bacteria/comammox), while penicillic acid reduced archaeal amoA abundance and the relative abundance of Nitrosospira (AOB) and the microbes listed above. Penicillic acid also strongly inhibited denitrification (33%) and N2O emissions (61%) at the peak of N2O production (day 4 of anaerobic incubation) via decreasing nitrate reductase gene (narG) abundance and increasing N2O reductase gene (nosZ) abundance, respectively. Furthermore, the environmental risks of QSIs to microbial community structure and network stability, CO2 emissions, and soil animals were acceptable. Overall, QSIs have application potential in agriculture to reduce soil N losses and the associated effect on climate change. This study established a new method to mitigate N losses from the perspective of QS, and can serve as important basis of decreasing the environmental risks of agricultural non-point source pollution.

Discovery of penicillic acid as a chemical probe against tau aggregation in Alzheimer’s Disease

Alzheimer’s Disease (AD) is a neurodegenerative disorder proven to be caused by the aggregation of protein tau into fibrils, resulting in neuronal death. The irreparable neuronal damage leads to irreversible...

Exploring colorant production by amazonian filamentous fungi: Stability and applications.

The aim of this study was to investigate the production, stability and applicability of colorants produced by filamentous fungi isolated from soil samples from the Amazon. Initially, the isolates were evaluated in a screening for the production of colorants. The influences of cultivation and nutritional conditions on the production of colorants by fungal isolates were investigated. The colorants produced by selected fungal isolates were chemically characterized using the Liquid Chromatography-Mass Spectrometry technique. The antimicrobial and cytotoxic activities, stability evaluation and applicability of the colorants were investigated. As results, we observed that the isolates Penicillium sclerotiorum P3SO224, Clonostachys rosea P2SO329 and Penicillium gravinicasei P3SO332 stood out since they produced the most intense colorants. Compounds produced by Penicillium sclerotiorum P3SO224 and Clonostachys rosea P2SO329 were identified as sclerotiorin and penicillic acid. The colorant fraction (EtOAc) produced by these species has antimicrobial activity, stability at temperature and at different pHs, stability when exposure to light and UV, and when exposed to different concentrations of salts, as well as being nontoxic and having the ability to dye fabrics and be used as a pigment in creams and soap. Considering the results found in this study, it was concluded that fungi from the soil in the Amazon have the potential to produce colorants with applications in the textile and pharmaceutical industries.

Compaction, aeration and addition of mycotoxin contaminated silage alters the fermentation profile, mycotoxin content and aerobic stability of ryegrass (Lolium perenne) silage

This study investigated the effect of compaction, aeration and addition of a naturally mycotoxin contaminated ryegrass silage (MCS) containing 1803 µg/kg DM penicillic acid, on the nutritional value and mycotoxin content after ensiling and subsequent aerobic stability of ryegrass Lolium perenne silage (second-cut, June 2020, UK). Mini silos (30 L) were filled with differential compaction (500 kg FW/m3 and 333 kg FW/m3), aeration by injection of air (1L per 48h for 30d then 1L per 7d) and addition of MCS (1.5 g/kg FW ensiled forage) in a 2×2×2 factorial design. During ensilage, mean CO2% (kg FW) in the aerated silos increased with low compaction. Crude protein (CP) increased and ash decreased with aeration. Mean silage fermentation end products acetic (AA), lactic (LA) and propionic acid (PA) concentrations increased with MCS. PA concentration increased with aeration/low compaction. LA decreased and ethanol increased with low compaction. Mycotoxin profiles differed between the silages on opening and after 14-days incubation in aerobic conditions with disappearance of fusarenon X and penicillic acid and appearance of mycophenolic acid and roquefortine C (318 µg/kg DM and 890 µg/kg DM). Addition of MCS, increased the concentration of penicillic acid on opening with an interaction with aeration (80.6µg/kg DM MCS × aerated, 40.0 µg/kg DM in the MCS × sealed). Aerobic stability was affected by aeration and low compaction with reduced time taken to heat to +5°C and +10°C above ambient temperature, higher rate of increase in pH and higher cumulative temperatures to the first peak temperature. Higher mycotoxin concentration at opening had a similar effect increasing time to heat +5°C and +10°C above ambient temperatures in aerobic conditions. Regression analysis showed predominantly direct relationships between silage fermentation end-product concentrations and aerobic stability. This study revealed interactions between silage bacteria and fungi activity from the concentrations of fermentation end-products and mycotoxins during ensilage and subsequent aerobic spoilage. The results supported current best practice for silage making, promoting conditions for improved preservation and aerobic stability. The addition of MCS had unexpected positive effects. However, factors associated with the MCS benefiting aerobic stability were not determined.

Antimicrobial and Cytotoxic Activities of the Secondary Metabolites of Endophytic Fungi Isolated from the Medicinal Plant Hyssopus officinalis.

According to the World Health Organization, it is estimated that by 2050, drug-resistant infections could cause up to 10 million deaths annually. Therefore, finding a new generation of antibiotics is crucial. Natural compounds from endophytic fungi are considered a potential source of new-generation antibiotics. The antimicrobial and cytotoxic effects of ethyl acetate extracts of nine endophytic fungal isolates obtained from Hyssopus officinalis were investigated for bioassay-guided isolation of the natural compounds. An extract of isolate VII showed the highest antimicrobial activities against Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus (30.12 ± 0.20 mm and 35.21 ± 0.20 mm) and Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa (30.41 ± 0.23 mm and 25.12 ± 0.25 mm) among the tested extracts of isolates. Molecular identification of isolate VII confirmed it as Chaetomium elatum based on sequencing of its ITS genes, and it was discovered that this was the first time C. elatum had been isolated from H. officinalis. This isolate was cultured at a large scale for the isolation and identification of the active compound. Penicillic acid was isolated for the first time from C. elatum and its chemical structure was established by NMR spectroscopy. The penicillic acid showed strong antibacterial activities against Bacillus subtilis and Staphylococcus aureus with 20.68 mm and 25.51 mm inhibition zones, respectively. In addition, MIC and MBC values and antibiofilm activities of penicillic acid were determined. It was found that penicillic acid reduced the level of biofilms in proportion to antibacterial activity.

Honey analysis in terms of nicotine, patulin and other mycotoxins contamination by UHPLC-ESI-MS/MS - method development and validation

Fifty-seven samples of honey of different types and origins were screened for nicotine and nine mycotoxins (aflatoxin B1, aflatoxin B2, fusarenon X, ochratoxin A, penicillic acid, zearalenone, sterigmatocystin, gliotoxin, and patulin). The sample set consisted of monofloral, multifloral, nectar, honeydrew, cream, and artificial honey originating mainly from Poland. The physicochemical characterization of honey was performed by determining colour (by Pfund method), water content (by refractometry), total phenolics and flavonoids content (by spectrophotometry). For nicotine and mycotoxins determination a QuEChERS-based UHPLC-ESI-MS/MS method was developed and validated. Analyses were carried out in alkaline conditions to ensure patulin-methanol adduct formation and facilitate this mycotoxin detection. About 33% of tested honey samples were contaminated by nicotine or/and mycotoxins. However, the presence of mycotoxins was not related to herein evaluated physicochemical parameters of honey samples.

Identification of Green Coffee Contaminated Microfungi of the Genus &lt;i&gt;Aspergillus&lt;/i&gt; on the Basis of Polyphasic Approach

The Aspergillus species are widespread in the environment, able to grow at high temperatures and minimal humidity, including in regions with a hot tropical climate. Some species have the potential to produce toxins. This causes the risk of contamination by fungi of the genus Aspergillus and the mycotoxins (MT) produced by them of plant materials and food products, which is possible at any stage of production, transportation and storage. In the volume of coffee imported to the Russian Federation, 85% is accounted for by raw materials (green coffee), for which the risks of mold damage remain at all stages preceding the roasting stage. It is relevant to study the species composition and toxinogenic properties of Aspergillus spp., which contaminate food raw materials for the production of mass consumption foodstuffs. Contaminated products include coffee, which is one of the basic products of the consumer basket. Reliable data on species identification and toxigenic potential of Aspergillus spp. can be obtained only with an integrated approach based on polyphasic taxonomy. The purpose of this work is to study the species composition of fungi of the genus Aspergillus isolated from green coffee using an integrated approach based on polyphasic taxonomy. The species composition of fungi of the genus Aspergillus from the internal mycoflora of 16 samples of green coffee beans of Arabica and Robusta. The species belonging of the isolated 34 singlspore isolates of Aspergillus spp. was determined by cultural and morphological methods and confirmed by molecular genetic analysis, i.e., RT-PCR with DNA markers of conservative sequences (ITS, CaM, β-tub), studied in vitro profile of produced secondary toxic metabolites. The dominance of species of the Niger section was established (A. niger, 90%, and A. tubingensis, A. carbonarius); then, in decreasing order, the species of section Flavi followed (A. flavus, 100%), sections Circumdati (A. ochraceus, 40% and A. westerdijkiae, 60%). In section Fumigati there was one strain of A. fumigatus. Analysis of the profile of toxic metabolites by HPLC-MS/MS in the multi-detection mode showed the production of mycotoxins by the following species: A. niger – fumonisin B2 and ochratoxin A, A. flavus – aflatoxins B1 and B2 together with sterigmatocystin, A. westerdijkiae – ochratoxin A and penicillic acid, A. ochraceus – penicillic acid. Amounts of produced MT show a high toxinogenic potential of Aspergillus spp. Thus, 20 out of 34 strains produced significant amounts of dangerous, regulated mycotoxins: AFL B1, OTA, FB2. Non-toxinogenic isolates were represented by the species A. niger, A. carbonarius, A. tubingensis, A. flavus, and A. fumigatus. A study of the species composition and toxinogenic properties of green coffee contaminants of the genus Aspergillus using a polyphasic approach was carried out in Russia for the first time.

Thioredoxin Is a New Target for the Phytotoxicity of Small Lactone Mycotoxins, Patulin and Penicillic Acid on Maize Seedlings

The phytotoxic mechanisms of patulin (PAT) and penicillic acid (PA) have not been identified unambiguously. This study aims to clarify their effects on thioredoxins (Trxs). Aflatoxin B1 (AFB1), PAT and PA were isolated by solvent extraction and chromatographic techniques from the cultures of Aspergillus flavus Z2 (LC171449), Penicillium vulpinum CM1 and Aspergillus ochraceus EMCC516, respectively. The three mycotoxins showed phytotoxicity to the germination of maize seeds, which was manifested by inhibiting radicle and coleoptile emergence, in addition to their toxic effects on fresh weights and root and shoot lengths. The phytotoxicity of AFB1 and PAT was greater than that of PA. Due to the central roles exhibited by plant Trxs in cellular metabolic activities, they were tested as target proteins for PAT and PA using AFB1 as positive control. In vivo studies showed that the mycotoxins significantly reduced Trx activity measured in the roots and shoots of maize seedlings. PAT showed greater Trx-inhibiting activity than PA and AFB1. In vitro studies of the mycotoxins on Trx y1 (from Arabidopsis thaliana) and thioredoxin reductase (Tr, from rat liver) activities confirm the results of in vivo studies. The inactivation of Trx with PAT and PA was reduced in the presence of glutathione (GSH). Data obtained suggest that lactone mycotoxins are more highly reactive with simple low-molecular-weight thiols (like GSH) than with complex ones (like Trx).

Antimicrobial and Cytotoxic Activity of Endophytic Fungi from Lagopsis supina.

In this study, five endophytic fungi belonging to the Aspergillus and Alternaria genera were isolated from Lagopsis supina. The antimicrobial activity of all fungal fermented extracts against Staphylococcus and Fusarium graminearum was tested using the cup-plate method. Among them, Aspergillus ochraceus XZC-1 showed the best activity and was subsequently selected for large-scale fermentation and bioactivity-directed separation of the secondary metabolites. Four compounds, including 2-methoxy-6-methyl-1,4-benzoquinone (1), 3,5-dihydroxytoluene (2), oleic acid (3), and penicillic acid (4) were discovered. Here, compounds 1 and 4 displayed anti-fungal activity against F. graminearum, F. oxysporum, F. moniliforme, F. stratum, Botrytis cinerea, Magnaporthe oryzae, and Verticillium dahliae with diverse MIC values (128-512 μg/ml), which were close to that of the positive control antifungal, actidione (64-128 μg/ml). Additionally, compounds 1 and 4 also exhibited moderate antibacterial activity against S. aureus, Listeria monocytogenes, Escherichia coli, and Salmonella enterica, with low MIC values (8-64 μg/ml). Moreover, compounds 1 and 4 displayed selective cytotoxicity against cancer cell lines as compared with the normal fibroblast cells. Therefore, this study proposes that the endophytic fungi from L. supina can potentially produce bioactive molecules to be used as lead compounds in drugs or agricultural antibiotics.

Mycotoxin contamination of fresh berries and fruits marketed in the central region of Russia

New emerging strains of toxigenic molds in agricultural areas and insufficient data on levels of their toxic metabolites occurring in domestic horticultural fruits and berries require risk assessment of MT contamination for this plant group of mass consumer products. This study concentrated on samples of fresh fruits and berries sold on the consumer market (185 samples, including 127 intact and 58 with signs of deformation and molding). We applied our own developed technique for quantification of mycotoxins based on HPLC-MS/MS. In this study, we were the first in the RF to examine contamination of garden strawberries, raspberries, currants, huck-leberries, blueberries, gooseberries, dogwood, plums, blackthorn, apples, pears) with 27 MT including poorly studied emergent MT (EMT), produced by Aspergillus, Penicillium, Fusarium and Alternaria. Strawberries, gooseberries, black currants and raspberries turned out to be the most contaminated with MT; red currants, apples and pears were less contaminated. The greatest variety of MT and EMT species was found in strawberries (23 MT), gooseberries (8 MT), black currants (7 MT) and raspberries (6 MT). Among the regulated MT, fumonisins B1 and B2, deoxynivalenol, zearalenone, T-2 toxin, ochratoxin A and aflatoxin B1 were detected in intact strawberries; patulin, in raspberries; deoxynivalenol and zearalenone, in black currant. As for damaged and moldy berries and fruits, the list of detectable toxins was expanded, primarily due to the detection of several types of unregulated EMTs. EMT tenuazonic acid was mainly detected in moldy berries; its levels increased manifold in almost all species, except for strawberries in which penicillic acid prevailed. These new data on MT contamination in fruits and berries indicate the necessity to perform in-depth hygienic assessment of such products sold on the Russian market to identify MT, EMT and their producers. The obtained results will be used to identify hazards at the first stage in risk assessment with its focus on MT and EMT contamination of fresh fruits and berries.

Оценка потенциальной опасности влияния риск-индуцирующих факторов образовательного процесса и среды обитания на соматическое здоровье учащихся школ различного типа

New emerging strains of toxigenic molds in agricultural areas and insufficient data on levels of their toxic metabolites occurring in domestic horticultural fruits and berries require risk assessment of MT contamination for this plant group of mass consumer products. This study concentrated on samples of fresh fruits and berries sold on the consumer market (185 samples, including 127 intact and 58 with signs of deformation and molding). We applied our own developed technique for quantification of mycotoxins based on HPLC-MS/MS. In this study, we were the first in the RF to examine contamination of garden strawberries, raspberries, currants, huck-leberries, blueberries, gooseberries, dogwood, plums, blackthorn, apples, pears) with 27 MT including poorly studied emergent MT (EMT), produced by Aspergillus, Penicillium, Fusarium and Alternaria. Strawberries, gooseberries, black currants and raspberries turned out to be the most contaminated with MT; red currants, apples and pears were less contaminated. The greatest variety of MT and EMT species was found in strawberries (23 MT), gooseberries (8 MT), black currants (7 MT) and raspberries (6 MT). Among the regulated MT, fumonisins B1 and B2, deoxynivalenol, zearalenone, T-2 toxin, ochratoxin A and aflatoxin B1 were detected in intact strawberries; patulin, in raspberries; deoxynivalenol and zearalenone, in black currant. As for damaged and moldy berries and fruits, the list of detectable toxins was expanded, primarily due to the detection of several types of unregulated EMTs. EMT tenuazonic acid was mainly detected in moldy berries; its levels increased manifold in almost all species, except for strawberries in which penicillic acid prevailed. These new data on MT contamination in fruits and berries indicate the necessity to perform in-depth hygienic assessment of such products sold on the Russian market to identify MT, EMT and their producers. The obtained results will be used to identify hazards at the first stage in risk assessment with its focus on MT and EMT contamination of fresh fruits and berries.

EPIGENETIC MODIFIERS AND MINERALS AS TOOLS TO DIVERSIFY SECONDARY METABOLITE PRODUCTION IN FUNGI

Secondary metabolite production of fungi can be modified by different approaches, including epigenetic modifiers, culture-dependent methods, and genomic-based methods. In this study, secondary metabolite production was explored in the presence of epigenetic modifiers and minerals using a microscale fermentation approach. Thirteen fungi originally isolated from mushrooms and soils were grown in 96-well microtiter plates (MTPs) using 70% of potato dextrose broth (PDB) with the addition of epigenetic modifiers and minerals in different combinations and concentrations. All cultures were fermented at 10 °C or 28 °C for 2, 3, or 5 weeks and extracted by solid phase extraction. The resulting extracts were subjected to high-performance liquid chromatography (HPLC) and the chromatograms were analyzed on a qualitative and quantitative basis. In addition, major secondary metabolites from four fungi were identified as penicillic acid, patulin, pseurotin A, and javanicin. Epigenetic modifiers and minerals induce significant changes in the profile of the secondary metabolites. Their usage combined with microscale fermentation provides a cost-efficient tool for exploring fungal secondary metabolism.

Biological Control Potential of Penicillium brasilianum against Fire Blight Disease.

Erwinia amylovora is a causative pathogen of fire blight disease, affecting apple, pear, and other rosaceous plants. Currently, management of fire blight relies on cultural and chemical practices, whereas it has been known that few biological resources exhibit disease control efficacy against the fire blight. In the current study, we found that an SFC20201208-M01 fungal isolate exhibits antibacterial activity against E. amylovora TS3128, and the isolate was identified as a Penicillium brasilianum based on the β-tubulin (BenA) gene sequence. To identify active compounds from the P. brasilianum culture, the culture filtrate was partitioned with ethyl acetate and n-butanol sequentially. From the ethyl acetate layer, we identified two new compounds (compounds 3-4) and two known compounds (compounds 1-2) based on spectroscopic analyses and comparison with literature data. Of these active compounds, penicillic acid (1) exhibited promising antibacterial activity against E. amylovora TS3128 with a minimal inhibitory concentration value of 25 μg/ml. When culture filtrate and penicillic acid (125 μg/ml) were applied onto Chinese pearleaf crab apple seedlings prior to inoculation of E. amylovora TS3128, the development of fire blight disease was effectively suppressed in the treated plants. Our results provide new insight into the biocontrol potential of P. brasilianum SFC20201208-M01 with an active ingredient to control fire blight.

Simultaneous determination of twelve mycotoxins in edible oil, soy sauce and bean sauce by PRiME HLB solid phase extraction combined with HPLC-Orbitrap HRMS.

A solid phase extraction-high-performance liquid chromatography-tandem Orbitrap high resolution mass spectrometry (HPLC-Orbitrap HRMS) method was established for the determination of 12 mycotoxins (ochratoxin A, ochratoxin B, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, HT-2 toxin, sterigmatocystin, diacetoxysciroenol, penicillic acid, mycophenolic acid, and citreoviridin) in edible oil, soy sauce, and bean sauce. Samples were extracted by 80:20 (v:v) acetonitrile-water solution, purified by PRiME HLB column, separated by aQ C18 column with mobile phase consisting of 0.5 mmol/L ammonium acetate-0.1% formic acid aqueous solution and methanol. The results showed that the limits of detection (LODs) and limits of quantification (LOQs) of 12 mycotoxins were 0.12–1.2 μg/L and 0.40–4.0 μg/L, respectively. The determination coefficients of 12 mycotoxins in the range of 0.20–100 μg/L were > 0.998. The average recoveries in soy sauce and bean sauce were 78.4–106.8%, and the relative standard deviations (RSDs) were 1.2–9.7% under three levels, including LOQ, 2× LOQ and 10 × LOQ. The average recoveries in edible oil were 78.3–115.6%, and the precision RSD (n = 6) was 0.9–8.6%. A total of 24 edible oils, soy sauce and bean sauce samples were analyzed by this method. AFB1, AFB2, sterigmatocystin and mycophenolic acid were detected in several samples at concentrations ranging from 1.0 to 22.1 μg/kg. The method is simple, sensitive, and rapid and can be used for screening and quantitative analysis of mycotoxin contamination in edible oil, soy sauce, and bean sauce.

New Evidences about the Carcinogenic Effects of Ochratoxin A and Possible Prevention by Target Feed Additives.

A review of the carcinogenic effects of ochratoxin A (OTA) on various tissues and internal organs in laboratory and farm animals is made. Suggestions are made regarding how to recognize and differentiate the common spontaneous neoplastic changes characteristic for advanced age and the characteristic neoplasia in different tissues and organs in laboratory animals/poultry exposed to OTA. The synergistic effects of OTA together with its natural combination of penicillic acid are also investigated regarding possible carcinogenic effects. The malignancy and the target location of OTA-induced neoplasia is studied. The sex-differences of such neoplasia are investigated in the available literature. The time of appearance of the first neoplasia is investigated in long-term carcinogenic studies with OTA-treated animals. The possibility of target feed additives or herbs to counteract the toxic and carcinogenic effects of OTA is studied in the available literature. Some effective manners of prophylaxis and/or prevention against OTA contamination of feedstuffs/foods or animal production are suggested. The suitability of various laboratory animals to serve as experimental model for humans with regard to OTA-induced tumorigenesis is investigated.

The Penicillium brasilianum Histone Deacetylase Clr3 Regulates Secondary Metabolite Production and Tolerance to Oxidative Stress.

Most of the biosynthetic gene clusters (BGCs) found in microbes are silent under standard laboratory cultivation conditions due to the lack of expression triggering stimuli, representing a considerable drawback in drug discovery. To access the full biosynthetic potential, studies towards the activation of cryptic BGCs are essential. Histone acetylation status is an important regulator of chromatin structure, which impacts cell physiology and the expression of BGCs. In this study, clr3, a gene encoding a histone deacetylase in Penicillium brasilianum LaBioMMi 136, is deleted and associated phenotypic and metabolic changes are evaluated. The results indicate reduced growth under oxidative stress conditions in the ∆clr3 strain, higher intracellular reactive oxygen species (ROS) levels, and a different transcriptional profile of 13 ROS-related genes of both strains under basal and ROS-induced conditions. Moreover, the production of 14 secondary metabolites, including austin-related meroterpenoids, brasiliamides, verruculogen, penicillic acid, and cyclodepsipeptides was evaluated in the ∆clr3 strain, most of them being reduced. Accordingly, the addition of epigenetic modulators responsible for HDAC inhibition into P. brasilianum’s growth media also culminated in the reduction in secondary metabolite production. The results suggest that Clr3 plays an essential role in secondary metabolite biosynthesis in P. brasilianum, thus offering new strategies for the regulation of natural product synthesis by assessing chromatin modification.

Adulteration identification of wheat flour in chestnut flour based on differences in mycotoxin contamination by liquid chromatography-tandem mass spectrometry

建立了分散固相萃取-超快速液相色谱-串联质谱法同时测定板栗粉和小麦粉中43种真菌毒素的方法,对48份板栗粉和80份小麦粉样品的污染状况进行调查,筛选出5种专属于小麦粉的标志性真菌毒素。样品采用84%(v/v)乙腈水溶液提取,提取液采用C18结合增强型脂质去除净化剂(EMR-Lipid)净化,采用响应曲面-中心组合设计优化分散固相萃取净化方法。净化液在BEH C18色谱柱(100 mm×2.1 mm, 1.7 μm)上分别采用0.1%甲酸水溶液和含0.1%甲酸的甲醇-乙腈(1:1, v/v)(电喷雾正离子模式)、水和乙腈(电喷雾负离子模式)为流动相进行梯度洗脱,分别采用电喷雾电离(ESI)正负离子模式检测,基质匹配曲线外标法定量。板栗粉中真菌毒素的3水平加标回收率在72.4%~109.4%之间,相对标准偏差(RSD)<7.5%;小麦粉中真菌毒素的3水平加标回收率在70.7%~112.9%之间,RSD<9.3%;两种基质中43种真菌毒素的定量限均在0.1~20.0 μg/kg之间,方法线性相关系数均大于0.9991。利用所建立的方法监测了128份样品,结果表明,两种基质普遍受到真菌毒素污染,其中脱氧雪腐镰刀菌烯醇及其衍生物3-乙酰化-脱氧雪腐镰刀菌烯醇、15-乙酰化-脱氧雪腐镰刀菌烯醇、雪腐镰刀菌烯醇、去环氧-脱氧雪腐镰刀菌烯醇仅在小麦粉中检出。采用GB 5009.111-2016同位素稀释液相色谱-串联质谱法验证,检测结果与本方法一致。所建立的方法简便、快速、灵敏、准确,可有效满足板栗粉和小麦粉中真菌毒素残留的检测要求,脱氧雪腐镰刀菌烯醇及其4种衍生物可以作为两种食品的掺假标志物。