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Simple Summary: Ochratoxin A (OTA), a nephrotoxic mycotoxin categorized as a possible carcinogenic agent, is a current problem in the cheese manufacturing industry. The main OTA producers are Penicillium nordicum and Penicillium verrucosum. Therefore, we aimed to investigate different cheese ripening phases to hinder OTA production. We elaborated cheese analogues, inoculated both fungal species, and performed two different ripening phases, at 10 and 15 °C. Despite the fact that both were able to grow, they did not express genes related to OTA production, and no OTA was detected during two weeks of ripening. Therefore, we show that, when the first phases of ripening are maintained at <15 °C, the possibility of OTA production is dramatically minimized. This information is of utmost importance for industries to enhance the safety of their cheese products, which positively impacts human health. A lack of control of the technological abiotic parameters apparent during cheese manufacture, including temperature and relative humidity, results in this dairy product being prone to mold contamination. Sometimes, inoculant molds are used to obtain the characteristic sensory properties of this type of product. However, during the maturation process, some unwanted molds can colonize the ripening cheese and produce mycotoxins. Mycotoxigenic molds such as Penicillium nordicum and Penicillium verrucosum can colonize ripened cheeses, contaminating them with ochratoxin A (OTA), a nephrotoxic 2B toxin. Thus, the presence of OTA in cheeses could represent a hazard to consumers' health. This study has evaluated the growth and OTA production of P. nordicum and P. verrucosum on a cheese analogue under simulated ripening conditions of 10 and 15 °C and 0.96 water activity (aw). Ecophysiological, molecular, and analytical tools assessed the mold growth, gene expression, and OTA production under these environmental conditions. Both species were able to effectively colonize the cheese under these ripening conditions. However, neither species expressed the otapks and otanps biosynthetic genes or produced phenotypic OTA. Therefore, these results suggest a relatively low risk of exposure to OTA for consumers of this type of cheese product. The conditions used were thus appropriate for cheese ripening to minimize the potential for contamination with such mycotoxins. An appropriate adjustment of the technological ripening parameters during such cheese manufacture could contribute to OTA-free cheeses. [ABSTRACT FROM AUTHOR]

A lack of control of the technological abiotic parameters apparent during cheese manufacture, including temperature and relative humidity, results in this dairy product being prone to mold contamination. Sometimes, inoculant molds are used to obtain the characteristic sensory properties of this type of product. However, during the maturation process, some unwanted molds can colonize the ripening cheese and produce mycotoxins. Mycotoxigenic molds such as Penicillium nordicum and Penicillium verrucosum can colonize ripened cheeses, contaminating them with ochratoxin A (OTA), a nephrotoxic 2B toxin. Thus, the presence of OTA in cheeses could represent a hazard to consumers’ health. This study has evaluated the growth and OTA production of P. nordicum and P. verrucosum on a cheese analogue under simulated ripening conditions of 10 and 15 °C and 0.96 water activity (aw). Ecophysiological, molecular, and analytical tools assessed the mold growth, gene expression, and OTA production under these environmental conditions. Both species were able to effectively colonize the cheese under these ripening conditions. However, neither species expressed the otapks and otanps biosynthetic genes or produced phenotypic OTA. Therefore, these results suggest a relatively low risk of exposure to OTA for consumers of this type of cheese product. The conditions used were thus appropriate for cheese ripening to minimize the potential for contamination with such mycotoxins. An appropriate adjustment of the technological ripening parameters during such cheese manufacture could contribute to OTA-free cheeses.

The main goals of the present investigation were to develop O/W nanoemulsion fungicides based on cold-pressed Nigella sativa (black seed) oil to prevent Penicillium verrucosum infection of maize seeds and to test their antifungal activity against this fungus. Additionally, the effect of these nanoemulsions on plant physiological parameters was also investigated. Two nonionic surfactants namely Tween 20 and Tween 80 were used as emulsifying agents in these formulations. The effect of sonication time and surfactant type on the mean droplet size, polydispersity index (PDI), and zeta potential of the nanoemulsions were determined by dynamic light scattering (DLS). Results indicated that both sonication time and emulsifier type had pronounced effects on the stability of O/W nanoemulsions with a small particle size range (168.6–345.3 nm), acceptable PDI (0.181–0.353), and high zeta potential (−27.24 to –48.82 mV). Tween 20 showed superior stability compared to Tween 80 nanoemulsions. The in vitro results showed that complete inhibition of P. verrucosum-growth was obtained by 10_T80 and 10_T20 nanoemulsions at 100% concentration. All nanoemulsions had increment effects on maize seed germination by 101% in the case of 10_T20 and 10_T80 compared to untreated seeds or the chemical fungicide treatment. Nanoemulsions (10_T20 and 10_T80) were able to stimulate root and shoot length as compared to the fungicide treatment. Seed treatment with 10_T80 nanoemulsion showed the highest AI and protease activity by 75 and 70%, respectively, as compared to the infected control. The produced nanoemulsions might provide an effective protectant coating layer for the stored maize seeds. [ABSTRACT FROM AUTHOR]

The main goals of the present investigation were to develop O/W nanoemulsion fungicides based on cold-pressed Nigella sativa (black seed) oil to prevent Penicillium verrucosum infection of maize seeds and to test their antifungal activity against this fungus. Additionally, the effect of these nanoemulsions on plant physiological parameters was also investigated. Two nonionic surfactants namely Tween 20 and Tween 80 were used as emulsifying agents in these formulations. The effect of sonication time and surfactant type on the mean droplet size, polydispersity index (PDI), and zeta potential of the nanoemulsions were determined by dynamic light scattering (DLS). Results indicated that both sonication time and emulsifier type had pronounced effects on the stability of O/W nanoemulsions with a small particle size range (168.6–345.3 nm), acceptable PDI (0.181–0.353), and high zeta potential (−27.24 to –48.82 mV). Tween 20 showed superior stability compared to Tween 80 nanoemulsions. The in vitro results showed that complete inhibition of P. verrucosum-growth was obtained by 10_T80 and 10_T20 nanoemulsions at 100% concentration. All nanoemulsions had increment effects on maize seed germination by 101% in the case of 10_T20 and 10_T80 compared to untreated seeds or the chemical fungicide treatment. Nanoemulsions (10_T20 and 10_T80) were able to stimulate root and shoot length as compared to the fungicide treatment. Seed treatment with 10_T80 nanoemulsion showed the highest AI and protease activity by 75 and 70%, respectively, as compared to the infected control. The produced nanoemulsions might provide an effective protectant coating layer for the stored maize seeds.

The paper’s aim was to select the optimal mineral medium for LDPE biodegradation by the strain Penicillium verrucosum CNM-FP-02. It was selected five mineral salt media (MSM), which differed in salt content and N/P ratio. After 40 days of submerged cultivation, the following parameters were determined: catalase activity and pH of cultural media, biomass accumulation, rate of LDPE degradation, optical microscopy, and the tensile testing of polyethylene. It was observed that catalase activity on all media, except MSM 4, was higher in the presence of LDPE. The addition of polyethylene to the growth media stimulated the fungal biomass accumulation by 19.3-93.1% (4 media out of 5 tested). The percentage of degradation of LDPE films was different, depending on the culture medium, from 0.41% to 0.92%. The most active LDPE films were degraded on medium MSM 2. Visualization of plastic strips under an optical microscope revealed the immobilization of the microorganism and the damage on the polyethylene surface. The tensile test showed increased elasticity of the plastic in the variants treated with fungal strain. In conclusion, in order to stimulate the biodegradation of LDPE by the strain P. verrucosum CNM-FP-02, the medium MSM 2 (N/P ratio 1:1) was selected.

The current study aimed to detect fungi contamination in agricultural mushroom samples Agaricus bisporus which was taken from some areas of Baqubah district in Diyala governorate. It was shown that all the samples were contaminated 100%, total colony formation ranged 3.264×10-3 to 5.596 ×10-3, the results recorded 253 fungal isolates. The Canaan region recorded the highest number of fungal isolates, which was 84 isolates, followed by the regions of Buhruz, Khan Bani Saad and Baqubah, which were 66, 54 and 49 fungal isolates, in that order. The results of the study also showed that the fungal isolates that were isolated from the white agricultural fungus belonged to 3 fungal genera, called by Aspergillus, Rhizopus and Penicilium. The genus Aspergillus was superior in the number of species belonging to it since 6 species were recorded at a rate of 75% compared to the genus Rhizopus for which one species was recordedonly Rhizopus spp. The genus Penicillium recorded one species with a rate of 12.5 % each. The total species that were isolated and diagnosed were 8 fungal species: Aspergillus niger, A. parasiticus, A. nidulans, A. tamarii, A. fumigatus, A.ochraceus, Rizopus spp. and Penicillium verrucosum. [ABSTRACT FROM AUTHOR]

The present study focused on phytofabrication of selenium nanoparticles (SeNPs) from Carica papaya extract and exploration of their multi-biofunctional features. Total phenolics and flavonoids of C. papaya fruit extract were determined as 23.30 ± 1.88 mg gallic acid equivalents and 19.21 ± 0.44 mg quercetin equivalents per gram, respectively, which suggested that C. papaya fruit extract could be a competitive reducing and stabilizing agent during phytofabrication of nanoparticles. UV–Vis and FTIR spectroscopy showed the formation of SeNPs from sodium selenite, which could be related to the reducing and stabilizing activities of C. papaya fruit extract. The SeNPs were found to be stable with a Zeta potential of −32 mV. The average hydrodynamic size of SeNPs was found as 159 nm by dynamic light scattering. The SeNPs showed a broader XRD pattern with no sharp Bragg's peaks and found to be amorphous. SEM showed that SeNPs were spherical in shape and EDX pattern showed that SeNPs were made up of Se (71.81%), C (11.41%), and O (14.88%). The HR-TEM picture showed that SeNPs were spherical in morphology and have a size range of 101–137 nm. The SeNPs exhibited potent antioxidant activity and their EC50 values (effective concentration required to inhibit 50% of radicals) were 45.65 ± 2.01 and 43.06 ± 3.80 μg/ml in DPPH and ABTS assays, respectively. The antimicrobial action of SeNPs was found as a broad spectrum and suppressed microbial pathogens in ascending order: fungi > Gram-positive bacteria > Gram-negative bacteria. The SeNPs have been demonstrated to reduce the growth and ochratoxin A (OTA) of mycotoxigenic Aspergillus ochraceus and Penicillium verrucosum at 40 μg/ml in broth culture, which is noteworthy. The SeNPs reduced cancer cell proliferation (RAW 264.7, Caco-2, MCF-7, and IMR-32) more preferentially than normal cells (Vero), found to be highly biocompatible. Lower doses of SeNPs (up to 50 μg/ml) were shown to be less toxic and did not cause death in Danio rerio (zebrafish) embryos, implying that lower doses of SeNPs could be beneficial for biological purposes. The present study concluded that phytofabricated SeNPs have multiple biofunctional properties, including antioxidant, antimicrobial, antimycotoxin, and anticancer activities, as well as high biocompatibility. [ABSTRACT FROM AUTHOR]

The study is directed to establish the minimizing effects of Syzygium aromaticum, Ocimum sanctum, and Cananga odorata essential oils on the growth and ochratoxin A (OTA) level of Aspergillus ochraceus and Penicillium verrucosum in maize grains. S. aromaticum essential oil (SAEO), O. sanctum essential oil (OSEO), and C. odorata essential oil (COEO) were extracted by hydro-distillation technique, and a total of 50, 44, and 48 chemical constituents were identified by gas chromatography-mass spectrometry (GC-MS), respectively. The SAEO and OSEO belong to the chemotype of eugenol, whereas, COEO was found to be the chemotype of thymol, limonene, and a-ylangene. The antifungal activity of essential oils (EOs) was determined by the micro-well dilution technique. The SAEO showed superior antifungal activity compared to OSEO, COEO, and synthetic antifungal agent nystatin, and its minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values against A. ochraceous and P. verrucosum were noticed as 1251 ± 42.32 and 1878 ± 28.47 µg/mL, and 0815 ± 22.69 and 1146 ± 51.19 µg/mL, respectively. The antifungal mechanism of EOs was unveiled by assessing the intracellular reactive oxygen species (ROS), ergosterol content, and membrane integrity. The antifungal investigations found that EOs caused fungal mortality by increasing the intracellular ROS, depleting ergosterol synthesis, and distracting membrane integrity. Finally, antifungal and antimycotoxin activity of EOs was demonstrated in maize grains. The SAEO, OSEO, and COEO have reduced the complete fungal growth and OTA level of A. ochraceous and P. verrucosum correspondingly at 2500 and 2500, 3500 and 2500, and 3500 and 3500 µg/g in maize. The EOs could act as natural antifungal agents; protect foodstuffs from fungal infection and mycotoxins during storage. [ABSTRACT FROM AUTHOR]

Aflatoxins (AF) and ochratoxin A (OTA) are fungal metabolites that have carcinogenic, teratogenic, embryotoxic, genotoxic, neurotoxic, and immunosuppressive effects in humans and animals. The increased consumption of plant-based foods and environmental conditions associated with climate change have intensified the risk of mycotoxin intoxication. This study aimed to investigate the abilities of eleven selected LAB strains to reduce/inhibit the growth of Aspergillus flavus, Aspergillus parasiticus, Aspergillus carbonarius, Aspergillus niger, Aspergillus welwitschiae, Aspergillus steynii, Aspergillus westerdijkiae, and Penicillium verrucosum and AF and OTA production under different temperature regiments. Data were treated by ANOVA, and machine learning (ML) models able to predict the growth inhibition percentage were built, and their performance was compared. All factors LAB strain, fungal species, and temperature significantly affected fungal growth and mycotoxin production. The fungal growth inhibition range was 0–100%. Overall, the most sensitive fungi to LAB treatments were P. verrucosum and A. steynii, while the least sensitive were A. niger and A. welwitschiae. The LAB strains with the highest antifungal activity were Pediococcus pentosaceus (strains S11sMM and M9MM5b). The reduction range for AF was 19.0% (aflatoxin B1)-60.8% (aflatoxin B2) and for OTA, 7.3–100%, depending on the bacterial and fungal strains and temperatures. The LAB strains with the highest anti-AF activity were the three strains of P. pentosaceus and Leuconostoc mesenteroides ssp. dextranicum (T2MM3), and those with the highest anti-OTA activity were Leuconostoc paracasei ssp. paracasei (3T3R1) and L. mesenteroides ssp. dextranicum (T2MM3). The best ML methods in predicting fungal growth inhibition were multilayer perceptron neural networks, followed by random forest. Due to anti-fungal and anti-mycotoxin capacity, the LABs strains used in this study could be good candidates as biocontrol agents against aflatoxigenic and ochratoxigenic fungi and AFL and OTA accumulation.

Aflatoxins (AF) and ochratoxin A (OTA) are fungal metabolites that have carcinogenic, teratogenic, embryotoxic, genotoxic, neurotoxic, and immunosuppressive effects in humans and animals. The increased consumption of plant-based foods and environmental conditions associated with climate change have intensified the risk of mycotoxin intoxication. This study aimed to investigate the abilities of eleven selected LAB strains to reduce/inhibit the growth of Aspergillus flavus , Aspergillus parasiticus , Aspergillus carbonarius , Aspergillus niger , Aspergillus welwitschiae , Aspergillus steynii , Aspergillus westerdijkiae , and Penicillium verrucosum and AF and OTA production under different temperature regiments. Data were treated by ANOVA, and machine learning (ML) models able to predict the growth inhibition percentage were built, and their performance was compared. All factors LAB strain, fungal species, and temperature significantly affected fungal growth and mycotoxin production. The fungal growth inhibition range was 0-100%. Overall, the most sensitive fungi to LAB treatments were P. verrucosum and A. steynii , while the least sensitive were A. niger and A. welwitschiae . The LAB strains with the highest antifungal activity were Pediococcus pentosaceus (strains S11sMM and M9MM5b). The reduction range for AF was 19.0% (aflatoxin B1)-60.8% (aflatoxin B2) and for OTA, 7.3-100%, depending on the bacterial and fungal strains and temperatures. The LAB strains with the highest anti-AF activity were the three strains of P. pentosaceus and Leuconostoc mesenteroides ssp. dextranicum (T2MM3), and those with the highest anti-OTA activity were Leuconostoc paracasei ssp. paracasei (3T3R1) and L. mesenteroides ssp. dextranicum (T2MM3). The best ML methods in predicting fungal growth inhibition were multilayer perceptron neural networks, followed by random forest. Due to anti-fungal and anti-mycotoxin capacity, the LABs strains used in this study could be good candidates as biocontrol agents against aflatoxigenic and ochratoxigenic fungi and AFL and OTA accumulation.