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Penicillium expansum is the causal agent of blue mold in harvested fruits and vegetables during storage and distribution, causing serious economic loss. In this study we seek the action modes of bifonazole against this pathogen. Bifonazole exhibited strong antifungal activity against P. expansum by inhibiting ergosterol synthesis. The ergosterol depletion caused damage to the cell structure and especially cell membrane integrity as observed by SEM and TEM. With increased unsaturated fatty acids contents, the cell membrane viscosity decreases and can no longer effectively maintain the cytoplasm, which ultimately decreases extracellular conductivity, changes intracellular pH and ion homeostasis. Exposure of hyphal cells to bifonazole shows that mitochondrial respiration is inhibited and reactive oxygen species (ROS) levels–including H2O2 and malondialdehyde (MDA) – are significantly increased. The functional impairment of mitochondria and cell membrane eventually cause cell death through intrinsic apoptosis and necroptosis.

Chemical investigation of the culture extract of an endophytic Penicillium citrinum from Dendrobium officinale, afforded nine citrinin derivatives ( 1 – 9 ) and a peptide-polyketide hybrid GKK1032B ( 10 ). The structures of these compounds were determined on the basis of spectroscopic methods. The absolute configurations of 1 and 2 were determined for the first time by calculations of electronic circular dichroism (ECD) data. Among them, GKK1032B ( 10 ) showed significant cytotoxicity against human osteosarcoma cell line MG63 with an IC50 value of 3.49 μmol·L–1, and a primary mechanistic study revealed that it induced the apoptosis of MG63 cells via caspase pathway.

BACKROUND The study aims to reveal effects of hexanoic acid on microbial community, fermentation and hygienic quality of corn silages with or without fungal infection. Fungal infested (FI) and non-infested (NFI) whole-crop corn were separately ensiled without (control, CON) or with Hexanoic acid (Hex, 90% purity) at 0.2 g·kg-1 fresh weight (FW). RESULT The addition of Hex accelerated the pH decline during the first 5 d of ensiling regardless of fungal infestation. The lactic acid (LA) concentration in Hex silages was lower than that of CON during 45 d of ensiling, however the FI-Hex silage had the highest LA concentration among treatments on d 90. The Hex silage showed lower aflatoxin B1 (AFB1 ), zearalenone (ZEA), and deoxynivalenol (DON) concentrations than CON for FI silages. On d 5, the addition of Hex decreased the relative abundance of Klebsiella, Pantoea, and Enterobacter compared with CON regardless of fungal infestation, this inhibitory effect last until d 90 for NFI silages but disappeared for FI silages on d 90. The fungal infestation resulted in accumulation of Candida (34.05%) and Wickerhamomyces (19.46%). Hex decreased the relative abundance of Asperigillus, Issatchenkia and Penicillium for NFI silages on d 5, however its inhibitory effects was not observed in FI silages on d 5. CONCLUSION Fungal infestation was associated with poor fermentation and hygienic quality of corn silage, adding Hex accelerated the pH decline and maintained the antifungal activity until 90 d of ensiling, attenuating adverse effects of fungal infestation on the fermentation and preventing the accumulation of mycotoxins in corn silages. This article is protected by copyright. All rights reserved.

Due to the dissemination of airborne conidia and spores, molds can contaminate various surfaces. In the food industry sector, their presence and development can have health and economic implications. In order to control these undesirable microorganisms, various approaches can be used but the main one relies on the use of disinfectants. The objective of this review is to report the existing studies on the effect of various disinfectant molecules (i.e., sodium hypochlorite, chlorine dioxide, ethanol and other alcohols, hydrogen peroxide, peracetic acid, and quaternary ammonium compounds) on the inactivation of fungal spores. These studies were sorted depending on the targeted fungal species. Noteworthy, in the food industry, four log and three log reductions are required to claim a fungicidal activity for suspension (European Standard 1650, 2019) and surface (European Standard 13697/IN1, 2019) treatments, respectively. Most of the presented studies concerned Penicillium and Aspergillus species (44 and 31% of the literature, respectively). In general, for a given disinfection procedure, ascospores were more resistant than conidia, and Aspergillus conidia were more resistant than Penicillium ones. However, the variability of encountered molds (e.g. species, strains, physiological state) and disinfection procedures (e.g. molecules, concentrations, contact time) affected the efficacy of disinfectants.

Four new N-methyl-4-quinolones (1–4) and a new citrinin dimer derivative (10) with fourteen known compounds (5–9, 11–19) were isolated from the sponge-derived fungus Penicillium sp. SCSIO41303. Their structures and absolute configurations were elucidated by extensive spectroscopic analysis, electronic circular dichroism (ECD) calculation, and X-ray single-crystal diffraction. Most of the isolated compounds were evaluated for their cytotoxic, antibacterial, anti-virus, and enzyme inhibitory activities against acetylcholinesterase (AChE), and pancreatic lipase (PL). Compounds 2 and 11 exhibited enzyme inhibition activity against PL with IC50 values of 24.6 and 7.2 μg/mL, respectively. Besides, compound 11 showed enzyme inhibition activity against AChE with IC50 value of 16.5 μg/mL. Compound 15 showed moderate inhibition activities with 52.2% at the concentration of 50 μg/mL against PL and antibacterial activity against Staphylococcus aureus displaying diameter of about 10 mm.

Decay due to fungal infection is a major cause of postharvest losses in fruits. Acidic fungi may enhance their virulence by locally reducing the pH of the host. Several devastating postharvest fungi, such as Penicillium spp., Botrytis cinerea, and Sclerotinia sclerotiorum, can secrete gluconic acid, oxalic acid, or citric acid. Emerging evidence suggests that organic acids secreted by acidic fungi are important virulence factors. In this review, we summarized the research progress on the biosynthesis of organic acids, the role of the pH signalling transcription factor PacC in regulating organic acid, and the action mechanism of the main organic acid secreted via postharvest pathogenic fungi during infection of host tissues. This paper systematically demonstrates the relationships between tissue acidification and postharvest fungal pathogenicity, which will motivate the study of host–pathogen interactions and provide a better understanding of virulence mechanisms of the pathogens so as to design new technical strategies to prevent postharvest diseases., Organic acids secreted by acidic fungi in the growth medium or in the decayed fruit tissue modulate environmental pH and pathogenicity.

Guided by Global Natural Products Social molecular networking, two p-terphenyl derivatives and one 4,5-diphenyl-2-pyrone analogue, peniterphenyls A-C (1-3), together with five known p-terphenyl derivatives (4-8) and sulochrin (9), were obtained from a deep-sea-derived Penicillium sp. SCSIO41030. Their structures were elucidated using extensive NMR spectroscopic and HRESIMS data and by comparing the information with literature data. Peniterphenyl B (2) represented the first reported natural product possessing a 4,5-diphenyl-substituted 2-pyrone derivative. The p-terphenyl derivatives displayed inhibitory activities against HSV-1/2 with EC50 values ranging from 1.4 ± 0.6 to 9.3 ± 3.7 μM in Vero cells, which showed that they possessed antiviral activities with low cytotoxicity, superior to the current clinical drug acyclovir (EC50 3.6 ± 0.7 μM). Peniterphenyl A (1) inhibited HSV-1/2 virus entry into cells and may block HSV-1/2 infection through direct interaction with virus envelope glycoprotein D to interfere with virus adsorption and membrane fusion, and thus differs from the nucleoside analogues such as acyclovir. Our study indicated peniterphenyl A (1) could be a promising lead compound against HSV-1/2.

One new citrinin monomer derivative (1), and two new natural products α-pyrone analogues (2a and 2b), were isolated from the sponge derived fungus Penicillium sp. SCSIO 41302. Their structures were determined by extensive spectroscopic analysis, chiral-phase HPLC analysis, modified Mosher's method, ECD calculations, and X-ray single-crystal diffraction. Bioactivity screening showed that compounds 2b and 8 exhibited obvious inhibitory activities against pancreatic lipase and acetyl cholinesterase with IC50 values of 48.5 and 4.8 μM, respectively, which indicated that different chiral center between enantiomers (2a and 2b) might result in different biological activities (IC50 value against PL for 2a >100 μg/ml).

Abstract Cytochrome P450 monooxygenases (P450s) are considered nature’s most versatile catalysts and play a crucial role in regio- and stereoselective oxidation reactions on a broad range of organic molecules. The oxyfunctionalisation of unactivated carbon-hydrogen (C-H) bonds, in particular, represents a key step in the biosynthesis of many natural products as it provides substrates with increased reactivity for tailoring reactions. In this study, we investigated the function of the P450 enzyme TraB in the terrestric acid biosynthetic pathway. We firstly deleted the gene coding for the DNA repair subunit protein Ku70 by using split marker-based deletion plasmids for convenient recycling of the selection marker to improve gene targeting in Penicillium crustosum. Hereby, we reduced ectopic DNA integration and facilitated genetic manipulation in P. crustosum. Afterward, gene deletion in the Δku70 mutant of the native producer P. crustosum and heterologous expression in Aspergillus nidulans with precursor feeding proved the involvement of TraB in the formation of crustosic acid by catalysing the essential hydroxylation reaction of viridicatic acid. Key points •Deletion of Ku70 by using split marker approach for selection marker recycling. •Functional identification of the cytochrome P450 enzyme TraB. •Fulfilling the reaction steps in the terrestric acid biosynthesis.

Spices are parts of plants or plant substances primarily used for flavouring and preservation of food. Spices can be exposed to microbial contamination and toxic substances such as mycotoxins during processing storage and distribution. The aim of the study was to determine the incidence of toxigenic moulds in food spices sold in open markets in Benin City. A total of 35 samples were obtained from three markets. Potato dextrose agar (PDA) and Aspergillus flavus and parasiticus agar (AFPA) were employed for the isolation, characterization and identification of fungal isolates using standard microbiological procedures. The pH was determined using an electronic pH meter, titratable acidity and moisture content were also determined using appropriate methods. Fungi isolated in this study included; Fusarium sp., Alternaria sp., Rhizopus sp., Geotrichum sp., Cladosporium sp., Aspergillus niger and Penicillium sp. The most occurring fungus was Fusarium sp. (26%) while Alternaria sp. (2%) was the least occurring fungus. The fungal load ranged from 0.33 - 28.67 x 103 sfu/g and the pH values of samples ranged from 4.83 – 5.67. The titratable acidity ranged from 0.037 – 0.521 mg/l, while the moisture content ranged from 2.0 – 28.0%. The study revealed the presence of toxigenic moulds such as Fusarium and Penicillium species in food spices sold in open markets. This may have resulted from improper storage, handling and poor sanitary conditions in the open markets.

Background The development of resistance to many antibiotics currently in use has necessitated the search for more effective alternatives. Plants have been used in ethnomedicine in different parts of the world to treat various diseases. Many studies on plants have confirmed their medicinal potentials and have led to the isolation and characterization of several potential drug candidates. This study investigates the leaves of Icacina trichantha for antimicrobial properties and seeks to identify the compounds responsible for the observed activities. The leaves of Icacina trichantha are used in ethnomedicine for the treatment of skin infections. In this study, a solvent-based fractionation of bioactive compounds in the leaves of Icacina trichantha was carried out using hexane, ethyl acetate, and methanol. The resultant extracts were screened for antimicrobial activity against six bacteria and four fungi using standard procedures. GC–MS analysis of the most active fraction was carried out. Results The non-polar fraction (hexane) showed better antimicrobial activity than the ethyl acetate and methanol extracts. At 200 mg/mL, the fraction showed inhibition of 28.0 ± 0.82, 23.7 ± 0.47, and 24.6 ± 0.94 against Staphylococcus aureus, Escherichia coli, and Bacillus subtilis,, respectively. At the same concentration, the extract showed zones of inhibition of 18.0 ± 0.82 against Candida albicans and Penicillium notatum. The lowest Minimum Inhibitory Concentrations (MIC) values of 2.5 mg/mL were obtained against Staphylococcus aureus, Escherichia coli, and Bacillus subtilis. GC–MS analysis of the hexane extract revealed 62 peaks, out of which ten peaks were successfully characterized. Conclusions None of the extracts screened for antibacterial and antifungal activities in this study is as potent as the standard drugs, Gentamicin and Tioconazole. The hexane extract, however, showed some activity against the microorganisms and was analyzed using GC–MS. The hexane extract contained many bioactive compounds, some of which could not be identified. Two of the identified compounds, Stigmasterol and β-Sitosterol, are known to possess antimicrobial properties. However, the unidentified compounds could also have contributed significantly to the antimicrobial activities of the extract.

Filamentous fungi can enter drinking water supply systems in various ways, and exist in suspended or sessile states which threatens the health of individuals by posing a high risk of invasive infections. In this study, the biofilms formation kinetics of the three genera of fungal spores, Aspergillus niger (A. niger), Penicillium polonicum (P. polonicum) and Trichoderma harzianum (T. harzianum) isolated from the groundwater were reported, as well as the effects of water quality parameters were evaluated. In addition, the efficiency of low- concentrations of chlorine-based disinfectants (chlorine, chlorine dioxide and chloramine) on controlling the formation of fungal biofilms was assessed. The results showed that the biofilms formation of the three genera of fungi could be divided into the following four phases: induction, exponential, stationary and sloughing off. The optimum conditions for fungal biofilms formation were found to be neutral or weakly acidic at 28 °C with rich nutrition. In fact, A. niger, P. polonicum, and T. harzianum were not observed to form mature biofilms in actual groundwater within 120 hr. Carbon was found to have the maximum effect on the fungal biofilms formation in actual groundwater, followed by nitrogen and phosphorus. The resistance of fungal species to disinfectants during the formation of biofilms decreased in the order: A. niger > T. harzianum > P. polonicum. Chlorine dioxide was observed to control the biofilms formation with maximum efficiency, followed by chlorine and chloramine. Consequently, the results of this study will provide a beneficial understanding for the formation and control of fungal biofilms.

This study was to investigate the cytotoxic and antimicrobial activities of ethyl acetate extract yielded from fermented fungi Trichoderma reesei strain: JCM 2267, Aspergillus flavus strain MC-10-L, Penicillium sp, and Aspergillus fumigatus associated with Stylissa flabelliformis sponge, and also to investigate the significant component in ethyl acetate extract of it. Antimicrobial experimentation was performed to various microbes with liquid microdilution method. The assessment of antimicrobials was undertaken by observing the value of MIC50. Cytotoxic testing was performed using MTT assay method. The cytotoxic activity evaluation was conducted by finding the value of IC50. The compound analysis in the ethyl acetate extract was used GC-MS. The result showed that in the antimicrobial experimentation, there was a variation in the percentage of inhibition where the smallest MIC50 values were found in Aspergillus fumigatus fungi ethyl acetate extract against Candida albicans ATCC 10231 at 1.3g/mL. The result of the cytotoxic test against tumor cell line T47D, the lowest IC50 was found in Penicillium sp fungi with 111g/mL value. Aspergillus flavus strain MC-10-L fungi, Penicillium sp, and Aspergillus fumigatus obtained from sponge isolation Stylissa flabelliformis have antimicrobial and cytotoxic activity with various range. All fungi extracts are not toxic against normal cells (Vero cells). The class of compounds in ethyl acetate fungi extract Trichoderma reesei strain JCM 2267 are mostly cyclohexane.

Penispidins A-C (1-3), new aromatic sesquiterpenoids with two classes of rare carbon skeletons, were isolated from the endophytic fungus Penicillium virgatum HL-110. 1 represents the first example of a dunniane-type aromatic sesquiterpenoid, possessing a novel 4/6/6 tricyclic system, while (±)-2 and 3 have a 7,12-cyclized bisabolene skeleton, featuring a 3,4-benzo-fused 2-oxabicyclo[3.3.1]nonane central framework. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and ECD calculations. 1 inhibited hepatic lipid accumulation in HepG2 cells.

Background Ochratoxin A (OTA) is a harmful mycotoxin and secondary metabolite produced by several species of Aspergillus and Penicillium. It is of vital importance to establish a sensitive method to detect OTA in various grains. Objective A novel, highly sensitive chemiluminescence immunoassay was developed to determine OTA in wheat, corn, and poultry feed. Methods The immunomagnetic beads were used as solid phase carriers and separators in the competitive chemiluminescence method. Anti-OTA monoclonal antibodies coated on the magnetic beads were applied as the capturing antibodies, in which OTA would compete with OTA-alkaline phosphatase in binding with OTA antibodies. Results The proposed method exhibited good linearity (R2 ≥ 0.999), adequate OTA recovery rate (83.60–102.50%), and good repeatability. The sensitivity of the proposed method was 2.05 pg/mL. In addition, the method was highly selective and showed no cross-reactions with other mycotoxins (e.g., AFB1, DON, ZEN). The developed method was applied in the analysis of wheat, corn, and two animal feeds successfully. The results obtained by the chemiluminescence method showed a high correlation with those obtained by the HPLC method (correlation coefficient 0.9958). Conclusion This strategy shows great potential for other toxic and harmful mycotoxin detection. Highlights A novel highly rapid and sensitive chemiluminescence immunoassay was established for quantitation of OTA.

Some rare sugars can be potently medicinal, such as l -gulose. In this study, we present a novel alditol oxidase (fAldOx) from the soil fungus Penicillium sp. KU–1, and its application for the effective production of l -gulose. To the best of our knowledge, this is the first report of a successful direct conversion of d -sorbitol to l -gulose. We further purified it to homogeneity with a ∼108-fold purification and an overall yield of 3.26%, and also determined the effectors of fAldOx. The enzyme possessed broad substrate specificity for alditols such as erythritol (kcat/KM, 355 m −1 s−1), thus implying that the effective production of multiple rare sugars for medicinal applications may be possible.

The effects of agrochemicals pollution on soil nutrients, soil microbes as well as plants cultivated on the soil were studied. Insecticide and herbicide were used to impact on the soil samples across concentration gradients. Bean and maize seeds were planted in separate experiments to monitor the effects of the agrochemicals on the plants. The microbial diversity and the physicochemical characteristics of the soil before and after pollution were determined using standard methods. Chlorophyll contents of the leaves were also determined after planting. Results indicated that bacterial isolates such asEnterococcus sp54(40%),Staphylococcussp 8(13%),Bacillus sp46(34%) andMicrococcus sp15(11%) and fungal isolates such asPenicillium sp41(34%),Saccharomyces sp67(56%), Yeast sp 4(3%),Geotrichum sp6 (5%) andAspergillus sp1(1.8%) were recovered from treated and untreated soil with the percentages representing after planting. From the results, the herbicide treated soils indicated that the Total Heterotrophic Bacterial Count (THBC) increased after cultivation while the Total Heterotrophic Fungal Count (THFC) decreased after cultivation. On the other hand, the insecticides treated soils recorded a general decrease in THFC and THBC after cultivation. The total nitrogen (TN) and available phosphorus (AP) had no significant differences before and after planting while the exchangeable potassium (EP) had significant increase recorded after planting. Plants generally had poor growth characteristics recorded by stem girth and length, as well as chlorophyll content.

Iridoids are widely found from species of Bignoniaceae family and exhibit several biological activities, such as anti-inflammatory, antimicrobial, antioxidant, and antitumor. Specioside is an iridoid found from Tabebuia species, mainly in Tabebuia aurea. Thus, here fungus-mediated biotransformation of the iridoid specioside was investigated by seven fungi. The fungus-mediated biotransformation reactions resulted in a total of nineteen different analogs by fungus Aspergillus niger, Aspergillus flavus, Aspergillus japonicus, Aspergillus terreus, Aspergillus niveus, Penicillium crustosum, and Thermoascus aurantiacus. Non-glycosylated specioside was the main metabolite observed. The other analogs were yielded from ester hydrolysis, hydroxylation, methylation, and hydrogenation reactions. The non-glycosylated specioside and coumaric acid were yielded by all fungi-mediated biotransformation. Thus, fungus applied in this study showed the ability to perform hydroxylation and glycosidic, as well as ester hydrolysis reactions from glycosylated iridoid. KEY POINTS: • The biotransformation of specioside by seven fungi yielded nineteen analogs. • The non-glycosylated specioside was the main analog obtained. • Ester hydrolysis, hydroxylation, methylation, and hydrogenation reactions were observe.

Filamentous fungi are frequent contaminants of many plant substrates and certain animal products. Their presence can improve the organoleptic quality of the product or alter it and lead to the accumulation of toxic secondary metabolites, such as mycotoxins. The objective of this work is to characterize the filamentous fungi isolated from the rice "deni kachia" stored and sold on public markets in the city of Daloa. A count and isolation of filamentous fungi, followed by macroscopic and microscopic identification was carried out. Several genera of filamentous fungi was identified. These are the genera Aspergillus, Penicillium and others. The different species of molds identified by conventional biochemical techniques were confirmed by the API 50 CH freezer.The genera Aspergillus and Penicillium are the most predominant in the samples analyzed. The presence of these species with their ability to produce mycotoxins suggests that contaminated rice poses a risk to the health of consumers.

Two new sclerotioramines (1 and 2) and a new natural product of sclerotioramine analog (3), together with seven known compounds have been isolated from the mangrove endophytic fungus Penicillium sclerotiorin SCNU-F0040. Their structures were identified based on the 1 D, 2 D NMR and HRESIM spectra. The absolute configurations of new compounds were deduced by specific rotation data and electronic circular dichroism spectra. All the isolated new compounds were tested on anti-diabetes activity by using a-glucosidase inhibition assay and anti-inflammatory activity by using cyclooxygenase inhibition assay, respectively. Compounds 1 and 2 have a-glucosidase inhibition activity with IC50 values of 102.3 and 217.5 μM. Compound 2 shows a moderate cyclooxygenase-2 inhibitory activity with an IC50 value of 47.8 μM.

A new indole diketopiperazine alkaloid, named penilline D (1), together with five known indole alkaloid analogues (2-5, 11), two meroterpenoids (6 and 12), and four butenolide derivatives (7-10), were isolated from the Antarctic fungus Penicillium sp. SCSIO 05705. Extensive spectroscopic analysis and electronic circular dichroism (ECD) calculation were used to elucidate the structure of penilline D (1), including its absolute configuration. All isolated compounds (1-12) were evaluated for their cytotoxic, antibacterial and enzyme inhibitory activities against acetylcholinesterase (AChE) and pancreatic lipase (PL). Among them, compound 5 exhibited moderate in vitro cytotoxic activity against the 143B cell line with IC50 value of 12.64 ± 0.78 μM. Compound 6 showed strong inhibitory activity against AChE with IC50 value of 0.36 nM (IC50 18.7 nM for Tacrine), while compounds 6 and 11 showed weak PL enzyme inhibitory activity. Furthermore, an in silico molecular docking study was also performed between 6 and AChE.

The tri-metallic oxide Ni/Cr/Cu nanoparticles (NPs) were synthesized using Coriander sativum extract as the reducing agent. The precursors namely CuSO4.5H2O, Ni(NO3)2·6H2O and Cr (NO3)3·9H2O were used for the green synthesis. Further, the prepared NPs were characterized using Ultraviolet-Visible (UV-Vis) spectroscopy and X-ray diffraction (XRD) studies. Its antimicrobial property against two fungal and two bacterial species was determined by measuring the respective zone of inhibition (ZOI) in well diffusion method. A dose dependent inhibition was observed in all the four species of pathogens including Escherichia coli, Staphylococcus aureus, Aspergillus flavus and Penicillium sp. This antimicrobial property of tri-metallic oxide NPs may be utilized in the field of medical research, pharmaceutical industries and environmental sciences.

One new benzophenone derivative, named penibenzophenone C (1), and a new benzophenone natural product, neamed penibenzophenone D (2), together with two known compounds (3, 4) were isolated from the EtOAc extract of the endophytic fungus Penicillium sp. isolated from the mangrove Acanthus ilicifolius L. collected in the South China Sea. The structures of 1–4 were elucidated by extensive NMR spectral interpretation and MS data. The new compounds 1 and 2 showed moderate antibacterial activities against methicillin-resistant Staphylococcus aureus with the MIC values of 3.12 and 6.25 μg ml−1, respectively.

Nuclease P1 (NP1) can hydrolyze nucleic acids into four 5′-mononucleotides, which are widely used in the pharmaceutical and food industries. In this paper, an aqueous two-phase system (ATPS) was developed to purify NP1 from Penicillium citrinum. Polyethylene glycol (PEG) and nucleotides salts were studied to form ATPSs, among which PEG3000/disodium guanosine monophosphate (GMPNa2) was researched, including the phase composition and pH. Using 14% (w/w) PEG3000 and 20% (w/w) GMPNa2 ATPS at pH 5.0, the best recovery and purification factor, 82.4% and 3.59, were obtained. The recovery of NP1 was 98.3% by the separation of ultrafiltration from the PEG-rich phase. The recycling use of GMPNa2 was also studied, and 95.1% of GMPNa2 in the salt-rich phase was obtained with the addition of ethanol as the solvent. These results showed that the ATPS was effective for purification of NP1.

A novel meroterpenoid, named meroterpenthiazole A (1), was isolated from the deep-sea-derived Penicillium allii-sativi. Its structure was established by extensive spectroscopic and computational methods. Meroterpenthiazole A bears a rare benzothiazole moiety in nature. Compound 1 significantly inhibited retinoid X receptor (RXR)-α transcriptional effect (KD = 12.3 μmol/L) through a novel binding mechanism.

Citrinin (CTN) is a mycotoxin, which is isolated from Penicillium citrinum and widely existed in the contaminated feeds. It is reported that CTN is toxic to heart, liver, and reproductive system. Previous studies indicated that CTN induced apoptosis in oocytes and embryos. In this study, we reported the potential causes of CTN on embryo development. Our results showed that 40 μM CTN exposure significantly reduced the first cleavage of mouse embryos, showing with the low rate of 2-cell embryos. We found that CTN induced DNA damage, showing the higher positive γH2A.X signals. Autophagy was occurred since more LC3 positive autophagosomes were found in the cytoplasm. This could be confirmed by the enhanced lysosome function, since higher accumulated lysosome distribution were found and LAMP2 was also increased under CTN exposure. Besides, we showed that mitochondria distribution was disturbed, indicating that CTN could disrupt mitochondria function, which could be the possible reason for the oxidative stress and apoptosis in CTN-exposed embryos. In conclusion, our study showed that CTN exposure had adverse effects on the early embryo development during first cleavage through its effects on the induction of DNA damage, autophagy, and mitochondria dysfunction.

Amylases are enzymes that catalyze the hydrolysis of glycosidic bonds present in starch to release simple sugars. They are one of the most important enzymes in numerous commercial processes. In this investigation, fungal and bacterial strains from the following agro-industrial wastes were isolated and screened for amylolytic ability: soil from oil palm plantation, shea seed, date fruit, coconut meat, cassava effluent, cassava peel, cassava tubers, yam and potato tubers, starch medium, parboiled water from noodles and rice. The results revealed the presence of Geotrichum, Aspergillus, Penicillium, Trichoderma, Rhizopus and Fusarium spp. Five major genera of bacterial species namely Corynebacterium, Pseudomonas, Lactobacillus, Micrococcus and Bacillus were isolated and screened for amylase activity. Cassava soil had the highest heterotrophic bacterial count of 5.7 x105cfu/g and coconut meat waste had the lowest heterotrophic bacterial count of 1.3 x105cfu/g. All isolated microorganisms had the amylolytic ability. The fungal isolates had higher amylase activity when compared with the bacterial isolates. This investigation reveals organisms with high amylase activity.

Mycotoxin-caused myocardial injury has been demonstrated based on epidemiological and experimental studies. Citreoviridin (CIT) is a toxin from yellow-green Penicillium easily grown in wet and cold...

A new isocoumarin, penicimarin N (1), along with five known compounds (2-6), were isolated from the mangrove-derived fungus Penicillium sp. TGM112. The structure of 1 was elucidated on the basis of extensive spectroscopic data analysis, and the absolute configuration of 1 was determined by comparison of their circular dichroism (CD) spectra with the literature. The structures of known compounds were determined by comparison with the literature data. All the isolated compounds were examined for their antioxidant and α-glucosidase activities. Compound 1 showed strong antioxidant activity with the IC50 value of 1.0 mM, and 1 also exhibited moderate inhibitory activity against α-glucosidase with the IC50 value of 620 μM.

The article presents the results of studies of the quantitative and specific composition of soil micromycetes in potato cultivation, depending on the intensity of irrigation in the north-east of Kazakhstan. During their growth in the soil, plants actively interact with its microflora, while microorganisms can have both positive and negative effects. Micromycetes produce mycotoxins that accumulate in food and, when ingested, cause liver damage and cancer. Some mycotoxins persist in the ground for a long time, and with improper agricultural processing, they accumulate in it, and are also removed from it to adjacent environments (surface reservoirs). As a result of the conducted studies, indicators of the quantitative and specific composition of fungi were obtained, antagonist fungi and toxin-forming species were identified. According to the results of the mycological analysis of soil samples, 39 isolates were isolated. During the study, the accumulation of toxin-forming species was found to be 43−54 % in all the studied variants. In the soil, when using irrigation, there are both pathogenic (18.1-50.0%) and saprophytic (50.0-81.9%) species of micromycetes, as well as toxin-forming species of fungi (46.2-55.6%) , which can cause different effects on the resistance of plants to potato diseases. The greatest number of pathogenic fungi, as well as toxin-forming fungi, was found when using limited watering of potatoes. The greatest number of pathogenic fungal species was observed in the variants with moderate irrigation −38.5 % (genera Fusarium − 30.8 %, Penicillium − 7.7 %), as well as in the variant with maximum irrigation – 50.0 % (genus Fusarium – 39.0%, from the genera Gliocladium and Aspergillus − 5.5%). Thus, the use of crop rotations and repeated fungicidal treatments carried out when growing potatoes does not guarantee the absence of pathogenic microorganisms in the soil, and the use of intensive watering provokes a stronger development of pathogenic microflora. New approaches to integrated potato protection are required.

Three unusual austins-type meroterpenoids penicianstinoids C-E (1-3) were obtained from the mangrove-derived fungus Penicillium sp. TGM112. The structures of 1-3 including absolute configurations were determined by detailed NMR, MS spectroscopic data, X-ray diffraction analysis, and calculated electronic circular dichroism data. Penicianstinoid C (1) was the first austins-type meroterpenoid with a unique 6/6/6/5 rearranged tetracyclic skeleton possessing two unusual spirocyclic moieties (2-oxaspiro[5.5]undeca-4,7-dien-3-one and 6-methylene-2-oxaspiro[4.5]decane-1,4-dione). Penicianstinoid D (2) was an unusual austins-type meroterpenoid with a 6/6/6/6 tetracyclic skeleton containing an octahydro-2H-chromen-2-one unit. Penicianstinoid E (3) possessed a 6/5/6/6/6/5 fused hexacyclic skeleton with an uncommon five-membered ether ring system. The plausible biosynthetic pathway of 1-3 is also proposed. Compounds 1 and 3 inhibited the growth of newly hatched Helicoverpa armigera Hubner larvae with IC50 values of 100 and 200 μg/mL, respectively.

Expression of a nonribosomal peptide synthetase-nonreducing polyketide synthase hybrid gene pcr10109 from Penicillium crustosum PRB-2 in Aspergillus nidulans led to the accumulation of 4-hydroxy-6-(4-hydroxyphenyl)-α-pyrone (1). Adding para-hydroxybenzoic acid into the medium in which the overexpressing mutant is growing increased the product yield up to 5-fold. This strategy could be helpful for heterologous gene expression experiments requiring special substrates for product formation.

The halotolerant phosphate-solubilizing fungus Penicillium sp. NAUSF2 was isolated from rhizospheric soil in coastal regions of South Gujarat, India, and identified on the basis of morphological characteristics and internal transcribed spacer gene sequence (ITS1 and ITS4). The isolate solubilized rock phosphate up to 843 µM. There was drop in pH with the secretion of gluconate (31.7 mM) and oxalate (3.2 mM) mediated by the high glucose oxidase and oxaloacetate acetylhydrolase activities, respectively. This fungus also demonstrated plant growth-promoting activities such as indole-3-acetic acid (127.82 g/L) and siderophore production. Inoculation of Penicillium sp. NAUSF2 to Vigna radiata (mung bean) significantly increased plant P uptake and growth parameters. It showed reduced disease severity index due to increased levels of antioxidative enzymes and jasmonic acid when treated with the leaf spot pathogen Xanthomonas axonopodis pv. V. radiata. These results suggest the potential of Penicillium sp. NAUSF2 as a biotechnological tool to help plants to cope up with stress in saline soils and broaden the spectrum of phosphate solubilizers available for field application.

The mycotoxin patulin is primarily produced as a secondary metabolite by numerous fungal species and predominantly by Aspergillus, Byssochlamys, and Penicillium species. It is generally associated with fungal infected food materials. Penicillium expansum is considered the only fungal species liable for patulin contamination in pome fruits, especially in apples and apple-based products. This toxin in food poses serious health concerns and economic threat, which has aroused the need to adopt effective detection and mitigation strategies. Understanding its origin sources and biosynthetic mechanism stands essential for efficiently designing a management strategy against this fungal contamination. This review aims to present an updated outline of the sources of patulin occurrence in different foods and their biosynthetic mechanisms. It further provides information regarding the detrimental effects of patulin on human and agriculture as well as its effective detection, management, and control strategies.

Prenylated indole alkaloids featuring spirooxindole rings possess a 3R or 3S carbon stereocenter, which determines the bioactivities of these compounds. Despite the stereoselective advantages of spirooxindole biosynthesis compared with those of organic synthesis, the biocatalytic mechanism for controlling the 3R or 3S-spirooxindole formation has been elusive. Here, we report an oxygenase/semipinacolase CtdE that specifies the 3S-spirooxindole construction in the biosynthesis of 21R-citrinadin A. High-resolution X-ray crystal structures of CtdE with the substrate and cofactor, together with site-directed mutagenesis and computational studies, illustrate the catalytic mechanisms for the possible β-face epoxidation followed by a regioselective collapse of the epoxide intermediate, which triggers semipinacol rearrangement to form the 3S-spirooxindole. Comparing CtdE with PhqK, which catalyzes the formation of the 3R-spirooxindole, we reveal an evolutionary branch of CtdE in specific 3S spirocyclization. Our study provides deeper insights into the stereoselective catalytic machinery, which is important for the biocatalysis design to synthesize spirooxindole pharmaceuticals., Prenylated indole alkaloids contain spirooxindole rings with a 3R or 3S carbon stereocenter, which determines their bioactivities, but the biocatalytic mechanism controlling the 3R- or 3S-spirooxindole formation was unclear. Here, the authors report the biochemical and structural characterization of the oxygenase/semipinacolase CtdE that catalyses the 3S-spirooxindole construction in the biosynthesis of 21R-citrinadin A.

Background: The presence of toxicogenic fungi and the production of ochratoxin in flour are dangerous to human health. Therefore, identification of these fungi by molecular and precise methods is essential. The aim of this study was molecular identification of fungal species and investigation of ochratoxin A contamination in flours used in bakeries in Hamadan Methods: In this descriptive-analytical study, 60 flour samples were collected from bakeries in Hamadan. At first, fungi were identified using phenotypic methods such as slide culture. Then, the genus and species of fungi were confirmed by PCR and sequencing of PCR products. ELISA method was used to detect ochratoxin A. Data were analyzed with GraphPad software version 6. Results: Of the 60 samples, 28 flour samples (46.66%) were free of fungal contamination and 32 flour samples (53.33%) were over fungal contamination (104 colonies/gr). Aspergillus and penicillium were the most abundant in samples. The prevalence of fungi in flour of Lavash bread, Sangak Bread, Barbari bread, Taftoon bread (Handmade), Taftoon bread (Machinal made), Stokbrood bread and Loaf bread were 50%, 46%, 35%, 31%, 26%, 18% and 11%, respectively. However, the highest levels of ochratoxin A were reported in flour of Lavash bread (3.98 ppb) and the lowest in Loaf bread (0.66 ppb). There was also a significant relationship between the fungal species and the amount of ochratoxin A production in flour of beards. Conclusion: While phenotypic and genotypic methods did not show the same sensitivity, the presence of ochratoxin in the studied flours indicated the necessity of modification in wheat storage and bakery flours.

Different growth stages of Penicillium notatum, P. purpurogenum and P. aculeatum were evaluated for their potential for zirconium nanoparticle (Zr-NP) biosynthesis by total protein content assay. Fungal secreted protein concentrations for all three species were higher at deceleration phase. For optimizing biosynthesis conditions with respect to Zr-NP size, different pH values and ZrCl4 concentrations were tested and analyzed. The artificial neural network (ANN) modeling was then applied to find the best conditions. A feed-forward ANN model was used to make a connection between the output as the size of Zr-NPs, with three input variables, including pH, ZrCl4 concentration and fungal species. An optimal multi-layer perceptron neural network was finally designed to model the experimental data for which the correlation coefficients R2 at each phase (training, validation and test sets) were calculated to be 0.9946, 0.9952 and 0.9997, respectively. The accuracy of the model was confirmed through validation experiments.

We found that l-gulose, a rare sugar, was produced from d-sorbitol efficiently, using a wheat-bran culture extract of the fungus Penicillium sp. KU-1 isolated from soil. The culture extract showed enzyme activity for the oxidation of d-sorbitol to produce l-gulose; a high production yield of approximately 94% was achieved.

The production and direct employment in organic medium in the synthesis of ethyl oleate of a solid fermented (FS) containing lipases of Penicillium roqueforti ATCC 10110 (PR10110), was investigated. For the production of this FS, the solid state fermentation of different agro-industrial waste was used, testing: cocoa shell, sugarcane bagasse, sugarcane bagasse with cocoa shell and cocoa shell with soybean oil and nutrient solution. The response surface methodology was used to study the effect of independent variables of initial moisture content (BMI) and inductor concentration, as carbon source and inducer (CS&I) on lipase production. The characterization of the fermented solid in organic medium was also carried out. The highest lipase activity (53±5 U.g-1) was 16% higher than that obtained with the non-optimized conditions. The characterization studies, was observed high stability of the FS in organic solvents for 5 h at 30°C, as well as at different temperatures, and the residual activity was measured against triolein. The FS was also able to catalyze ethyl-oleate synthesis maintaining high relative conversion over 5 reaction cycles of 96 h at 40°C in n-heptane. These results are promising and highlight the use of the FS containing lipases for first time in biocatalytic processes. This article is protected by copyright. All rights reserved.

Dry salted shrimp is a popular food in Acre cuisine, especially as a main ingredient in “tacacá” and “rabada no tucupi”. However, different intrinsic and extrinsic factors can result in accelerated deterioration and microbial proliferation, causing food poisoning to the consumer. The objective was to perform the counting and identification of molds and yeasts in dry salted shrimp in establishments that sell typical foods in the municipality of Rio Branco, state of Acre. Shrimp samples from six establishments were collected in sterile bottles, identified, refrigerated and transported to the Laboratory of Infectious Diseases of Animals at the Federal University of Acre, for the manual counting of colony-forming units and identification of fungal genera. As a result, the number of molds and yeasts in the dried salted shrimp samples varied between 1.0x102 and 1.02x106 CFU/g. Nine fungal genera were identified: Aspergillus, Penicillium, Cladosporium, Malassezia, Fusarium, Exophiala, Candida, Curvularia and Trichosporon. The most frequent were Aspergillus, Penicillium and Cladosporium, these being potential producers of mycotoxins. The presence of molds and yeasts in the samples of dried salted shrimp shows the need for greater hygienic-sanitary rigidity of this fish at different stages of manipulation and processing as preventative measures for public health.

Antifungal activity of extracts of cinnamon (Cinnamomum zeylanicum), Cloves (Syzygium aromaticum), ginger (Zingiber officinale) and turmeric (Curcuma longa) were evaluated in vitro against 17 Penicillium spp. Seed disease and rotten fruit caused by these species cause considerable loss of quality for different agricultural products. Isolates of Penicillium spp. were screened for production of patulin an important serious mycotoxin. About 70.59% of Penicillium spp. produced this toxin in concentrations ranging from 4 to 31 ppb. The response of Penicillium spp. to plant extracts differed according to the plant extract and concentration. Cinnamon extract showed the greatest effect on P. asperosporum, P. aurintogriseum and P. brevicompactum, and cloves extract produced the greatest effect on P. chermesinum and P. duclauxii. Turmeric extract had less effect on P. duclauxii. Cloves extract was the most effective in reducing the growth of Penicillium spp. On the other hand, ginger extract with all concentrations used had less effect against most Penicillium spp in the laboratory. Plant extracts are promising as natural sources of environmentally friendly compounds in laboratory studies.

Coculture fermentation of Penicillium fuscum and P. camembertii/clavigerum yielded berkeleypenostatins A-G (1-7) as well as the previously reported berkeleylactones A-H, the known macrolide A26771B, citrinin, and patulin. As was true with the berkeleylactones, there was no evidence of the berkeleypenostatins in either axenic culture. The structures were deduced from analyses of spectral data, and the absolute configuration of berkeleypenostatin A (1) was determined by single-crystal X-ray crystallography. Berkeleypenostatins A (1) and E (5) inhibited migration of human pancreatic carcinoma cells (HPAF-II). Both compounds were tested by the NCI Developmental Therapeutics Program. In the NCI 60 cell five-dose screen, berkeleypenostatin E (5) was the more active of the two, with 1-10 μM total growth inhibition (TGI) of all leukemia cell lines, as well as the majority of colon, CNS, melanoma, ovarian, prostate, renal, and breast cancer cell lines.

In this study, we investigated the antifungal activity of lactose oxidase (LO) as a potential biopreservative in dairy products. Our study objectives were to screen antifungal activity of LO against common mold strains, to detect the minimum inhibitory level of LO against the same strains, and to understand how LO affects the pH and lactic acid bacteria (LAB) counts in set yogurt. Five mold strains (Penicillium chrysogenum, Penicillium citrinum, Penicillium commune, Penicillium decumbens, and Penicillium roqueforti) were used throughout study. These strains were previously isolated from dairy manufacturing plants. Throughout the study, yogurts were stored at 21 ± 2°C for 14 d. Antifungal activity of LO was screened using 2 enzyme levels (1.2 and 12 g/L LO) against selected strains on the surface of a miniature laboratory set-yogurt model. For all tested strains, no visible mold growth was detected on the surface of yogurts covered with LO compared with control yogurt without LO. The minimum inhibitory level of LO against each strain was further investigated using 4 enzyme levels (0.12, 0.48, 0.84, and 1.2 g/L LO) on the miniature laboratory set-yogurt model. We detected 0.84 g/L LO as the minimum level inhibiting visible hyphal growth across strains. The minimum inhibitory level of LO varied for each individual strain. To study the effect of LO on the pH of yogurt, miniature laboratory set-yogurt models were covered with different enzyme levels (0.12, 0.48, 0.84, 1.2, and 12 g/L LO). At d 14, a difference was detected comparing pH values of treatments to control with no LO. Commercial low-fat set yogurt was used to study the effect of LO on LAB survival when yogurt surface was covered with 0.84 g/L LO under the same experimental conditions. Control with no LO was included. At d 14, 3 levels of catalase were added (0, 0.01, and 0.1%) to each treatment. To enumerate LAB, homogenized samples were plated on de Man, Rogosa, and Sharpe agar and incubated. Yogurts with 0.84 g/L LO had lower LAB counts compared with control yogurts, and catalase level did not have a significant effect on LAB counts. Our results demonstrated potential antifungal efficacy of LO against common spoilage organisms in dairy products with residual lactose and relatively low pH. Manufacturers should establish efficacy of LO against mold strains of interest and determine the effects of LO on organoleptic properties and LAB survival in set yogurt.

Pollution of the environment by hydrocarbon compounds has become a significant management challenge in oil-producing countries. Presently, the use of biological means for the reclamation of polluted sites is the most acceptable technique owing to its eco-friendliness. This study was carried out to assess the crude oil degradation potential of indigenous microorganisms in polluted soil. The polluted soil was obtained from a crude oil-ladened site in Okarki, River State, Nigeria. Bacterial and fungal organisms present in the polluted soil were isolated on Nutrient agar and Saboraud dextrose agar plates respectively. The isolates were identified based on their morphological, microscopic and biochemical characteristics. Gravimetric analysis of the crude oil degradation by the isolates was done in Bushnell Hass medium supplemented with 5% crude oil as the only carbon source. A total of 6 bacterial genera namely, Staphylococcus, Citrobacter, Micrococcus, Pseudomonas, Bacillus and Corynebacterium were identified while the fungal isolates were Aspergillus niger, Aspergillus flavus and Penicillium sp. Bacterial and fungal counts were 2.57±0.01 Log cfu/g and 2.08±0.07 Log cfu/g respectively. Bacillus sp. had the highest relative abundance (27.3%), while Micrococcus sp. and Corynebacterium sp. had the least occurrence (9.1%). Among the fungal group, A. niger showed the highest percentage occurrence in the polluted soil. All the indigenous organisms isolated from the polluted soil showed varying potentials for crude oil degradation. Bacillus sp. and Penicillium sp. were the highest crude oil-degrading bacterium and fungus respectively. The degradation potential of the bacterial consortium was significantly higher (P < 0.05) than the other consortia tested. This study has shown that indigenous organisms possess the potential for crude oil degradation.

The occurrence of secondary metabolites and co-contaminants in dairy cow feed samples (n = 115), concentrate, roughage, and mixed feed, collected from Ratchaburi and Kanjanaburi provinces, Thailand, between August 2018 and March 2019 were investigated using LC-MS/MS based multi-toxin method. A total of 113 metabolites were found in the samples. Fungal metabolites were the predominant compounds, followed by plant metabolites. Among major mycotoxins, zearalenone and fumonisins were most frequently detected in concentrate and mixed feed samples, while deoxynivalenol and aflatoxin B1 were found at the frequency lower than 50%. Other metabolites, produced by Aspergillus, Fusarium, Penicillium, and Alternaria species, occurred in the samples. Flavoglaucin, 3-nitropropionic acid, averufin, and sterigmatocystin were the most prevalent Aspergillus metabolites. Common Fusarium metabolites occurring in the samples included moniliformin, beauvericin, and enniatins. For Penicillium metabolites, mycophenolic acid, questiomycin A, quinolactacin A, oxaline, citrinin, and dihydrocitrinone were frequently detected. The toxic Alternaria metabolites, alternariol, and alternariol monomethyl ether showed the high incidence in the samples. Plant metabolites were commonly found, mainly cyanogenic compounds and isoflavones, from cassava and soybean meal used as feed ingredients. Overall, 96.6% of feed samples contained at least two metabolites, in a range from 2 to 69. According to co-contamination of mycotoxins found in feed samples, zearalenone were mostly found in combination with fumonisin B1, deoxynivalenol, and aflatoxin B1. Fumonisin B1 co-occurred with aflatoxin B1 and deoxynivalenol. The mixtures of deoxynivalenol and aflatoxin B1, and of zearalenone, fumonisin B1 and deoxynivalenol were also found. Due to known individual toxicity of fungal and plant metabolites and possible additive or synergistic toxic effects of multi-mycotoxins, the occurrence of these metabolites and co-contaminants should be monitored continuously to ensure food safety through the dairy supply chain.

Penicillium is one of the most important postharvest pathogens of citrus fruits worldwide. It induces blue or green mold disease, a decay that can lead to significant economic losses during storage. Based on internal transcribed spacer (ITS) sequences, seven Penicillium species and one closely related Talaromyces variabilis were identified from 30 rotten samples of citrus fruits marketed in Qena. Penicillium expansum was the most common species, recovered from 16.7% of the samples, followed by P. chrysogenum (10%) and P. polonicum (10%). Sixteen isolates were tested through inoculation on healthy citrus fruits; the data exhibited that 68.7% of isolates were highly virulent. A “Specific Gene Random Primer Polymerase Chain Reaction (SGRP-PCR)” marker technique indicated that the genetic similarity among P. expasum ranged from 49.4 to 85.7%, and a relatively correlation was found between SGRP band profile and species origin. Patulin was detected in 40% of P. expansum isolates. This study provided a useful molecular approach to identify different Penicillium species by sequencing ITS region, focus on the pathogenicity, compare between P. expansum isolates and their ability in patulin production.

Mycotoxins are toxic complexes generated by various genera of filamentous fungi and pose severe public health hazards due to their carcinogenic and mutagenic properties. Toxigenic fungi produce mycotoxins on various foodstuffs when favorable conditions for their production are exist. The most important mycotoxin-producing fungal genera are Aspergillus, Fusarium and Penicillium. The major mycotoxin of concern, including aflatoxins, trichothecenes, ochratoxins, patulin, fumonisins, and zearalenone, are expressively contaminate foodstuffs, with implications for human and animal health. There are various environmental factors influencing mycotoxin production involving temperature, water activity, animal type, aeration, pH, light, and nature of substrate. The temperature and relative moistness range for ideal mycotoxin generation may shift from that steady fungal development. The high temperature and moistness stress primarily have a potential issue. A full understanding of the existence of mycotoxins in addition the implementation measures to overcome their contamination of foodstuffs is crucial. There are different important analytical techniques to precisely screen the levels of mycotoxins contamination and give a wider overview about what is the most common, pathogenic; along with further strategies to control measures. Thus, in this review sampling, sample preparation and different analytical methods for determination of mycotoxins have been discussed.

Chitin is a polysaccharide component of the inner cell wall of fungi that has been used to estimate fungal invasion in plant products. However, its detection in major pathogenic fungal species has not been investigated. The present study aimed to determine the chitin contents of pathogenic fungal species in order to evaluate its diagnostic potential as a biomarker for fungal infections. High performance liquid chromatography (HPLC) was used to measure chitin content. Pure chitin was acid hydrolyzed and the fluorescence of 9-fluorenylmethylchloroformate (FMOC-CI) derivatives of glucosamine produced were measured. The chitin contents of ten pathogenic fungal isolates were determined per mycelial dry weight. They varied from 18.61 (± 0.09) to 47.12 (± 0.50) μg/mg dry mycelial weight. Candida albicans and Cryptococcus neoformans exhibited the highest and lowest levels of chitin, respectively. Based upon relative amounts of chitin produced, three groups namely: high (Candida albicans, Cryptococcus gattii, Aspergillus niger and Penicilliumat 47.12, 46.98, 46.05, and 44.15 μg/mg respectively), medium (Rhizopus, Aspergillus fumigatus, Fusarium solani, andMucor at 36.61, 36.30, 35.03, and 34.84 μg/mg, respectively), and low (Candida tropicalis and Cryptococcus neoformans at 20.78 and 18.61 μg/mg, respectively), were identified. Chitin was not detectable in bacterial isolates used as controls. The chitin detection method offers a sensitive and specific tool for the quantification of chitin in pathogenic fungal isolates. The detection of chitin may be a useful assay for the diagnosis of fungal infections in clinical samples.

The current study aimed to investigate antifungal activities of two commercially available essential oils (EOs), specifically Tea tree oil (Melaleuca alternifolia; TTEO) and St. John's wort oil (Hypericum perforatum; HPEO) against three Penicillium (P.) species: P. citrinum, P. expansum, and P. crustosum in in situ conditions. For this purpose, EOs were applied in the vapor phase to determine the growth inhibition of fungi artificially inoculated on sliced bread. Changes in colony growth rate were evaluated as markers for the mycelial growth inhibition (MGI) effect of the EOs. The antioxidant activities of the EOs were evaluated using the DPPH method. The moisture content (MC) and water activity (aw) of bread as a substrate for fungal growth were also measured. From the DPPH assay, we have found that both EOs (TTEO, HPEO) exhibited strong antioxidant activity (64.94 ±7.34%; 70.36 ±1.57%, respectively). The values for bread MC and aw were 43.01 ±0.341% and 0.947 ±0.006, respectively. Our results suggest that HPEO is the only weak inhibitor of P. citrinum and P. crustosum colony growths. Also, the highest concentrations of TTEO display only the weak capability of mycelial growth inhibition of P. citrinum and P. crustosum. By contrast, the colony growth of P. expansum was enhanced by both EOs at all levels used. In conclusion, the application of both EOs in the vapor phase against selected Penicillium species seems not to be a promising alternative to chemical inhibitors used for bread preservation.

Fungal natural products are rich sources of clinical drugs. Particularly, the fungicolous fungi have a large number of biosynthetic gene clusters (BGCs) to produce numerous bioactive natural products, but most BGCs are silent in the laboratory. We have shown that a fungicolous fungus Calcarisporium arbuscula NRRL 3705 predominantly produces the highly reduced polyketide-type mycotoxins aurovertins. Here after evaluation of the aurovertin-null mutant ΔaurA as an efficient host, we further screened two strong promoters aurBp and A07068p based on RNA-Seq, and successfully activated an endogenous gene cluster from C. arbuscula as well as three additional exogenous BGCs from other fungi to produce polyketide-type natural products. Thus, we showed an efficient expression system from the fungicolous fungus C. arbuscula, which will be highly beneficial and complementary to the conventional Aspergillus and Penicillium fungal cell factories, and provides a useful toolkit for genome-wide mining of bioactive natural products from fungicolous fungi.