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1.
Food Chem ; 366: 130541, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34273855

RESUMO

Penicillium oxalicum has been used as a biocontrol fungus in agriculture for many years, but the antimicrobial substances are still uncertain. Herein, we isolated a linear peptide named Sanxiapeptin in the culture broth of Penicillium oxalicum SG-4 collecting from the Three Gorges riparian zone. Sanxiapeptin exhibited potent inhibitory effect on citrus green mold Penicillium digitatum, the main fungi responsible for postharvest decay. Sanxiapeptin was elucidated as composing of five amino acids, which were ß-amino-α-methoxybutyric acid (Amoba), N-Me-l-Thr, d-Thr, N-Me-l-Val and l-Ser. By analyzing three chemically synthesized oligopeptides with similar structures, we found that the first amino acid of Amoba was crucial to the antifungal activity, as was the methylation of peptide bond. Sanxiapeptin may act as an antimicrobial agent by affecting the function of cell membranes or walls. The antimicrobial spectrum, safety and stability analysis supported that Sanxiapeptin was a promising antifungal agent for citrus preservation.


Assuntos
Citrus , Penicillium , Frutas , Doenças das Plantas
2.
Food Chem ; 369: 130959, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469836

RESUMO

The huge economic loss of citrus fruit after harvest called for safe and efficient preservatives, as chemically synthesized agents threatened the environment and human health. Herein a biocontrol fungus Chaetomium globosum QY-1 near the orchard in riparian area was identified to have antimicrobial, antioxidant and tyrosinase inhibition activity, which meets the requirements of an ideal preservative. Metabolite profiling based on bioassay-guided fractionation was carried out, and eight polyketones were determined by MS and NMR. The most abundant CheA exhibited strong inhibition to Penicillium digitatum, the main pathogen caused citrus fruit rot. Among these metabolites, Epicoccone and Epicoccolide B showed higher antioxidant activity, while Epicoccone and CheA had higher tyrosinase inhibitory activity. All the activities were close to or even better than the positive control (Vc; glutathione; Vc and arbutin; Bellkute), implying that the metabolites of C. globosum had comprehensive effects as natural preservatives.


Assuntos
Anti-Infecciosos , Chaetomium , Citrus , Humanos , Penicillium
3.
Chemosphere ; 286(Pt 1): 131591, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34303053

RESUMO

Drinking water safety cannot be overemphasized. Filamentous fungi have many excellent features for metal removal. Both graphene oxide (GO) and activated carbon (AC) are conventional metal adsorbents, but they are not suitable for large-scale use due to high cost. In this study, a low dosage of conidia (2.0 × 104 conidia/mL) of metal-resistant/adapted filamentous fungus Penicillium janthinillum strain GXCR were co-immobilized with a low dosage of 0.5 mg/L GO or 0.5 mg/L AC by embedding in 2% polyvinyl alcohol (PVA)-3% sodium alginate (SA), generating six types of microbead adsorbents (MBAs) to remove metals from a low concentration of either single metal (100 mg/L) or mixed metals (100 mg/L each) of Pb (II), Fe (III) and Cu (II) in drinking water. Fungus GXCR-containing MBAs had higher specific surface areas (SSAs), better mesoporous structures, and a higher removal rate (85-98.99%) of single or mixed metals. Singl-metal adsorptions of MBAs were almost unaffected by temperature changes. MBAs showed a stable removal rate of 87-94% during four cycles of adsorption-desorption of single metal. Single-metal adsorptions were well described by multiple models of Freundlich isotherm with constant values of 0.21-0.432, Langmuir isotherm with constant values of 0.037-0.17, Pseudo-fist-order, Pseudo-second-order, and intra-particle diffusion (IPD). In conclusion, co-immobilization between GXCR, GO and AC can make metal removal more efficient. Adsorption capacity is increased with SSAs but not in the same proportion. Single-metal adsorptions involve multiple mechanisms of monolayer and multilayer adsorptions, external mass transfer, and IPD. IPD is important but not the only one rate-controlling step for single-metal adsorptions.


Assuntos
Água Potável , Penicillium , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Compostos Férricos , Grafite , Cinética , Chumbo , Poluentes Químicos da Água/análise
4.
Pestic Biochem Physiol ; 179: 104976, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34802526

RESUMO

Induced resistance in harvested fruit and vegetables is a superior strategy to reduce postharvest decay. In the present study, Cinnamaldehyde (CA) was applied to investigate for its induced resistance against Penicillium digitatum and Geotrichum citri-aurantii. The results showed that 5250 mg CA/L wax was effective concentration in inducing the resistance of citrus fruit to green mold and sour rot. Wax+ CA (WCA) reduced significantly green mold and sour rot incidences at different exposure times, with 24 h being the optimal exposure time. The host reactions under infection with different pathogens were similar. During initial exposure, treatment with 5250 mg CA/L wax enhanced significantly the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenol oxidase (PPO), ß-1, 3-glucanase (GLU) and chitinase (CHT) in the presence of direct contact with the pathogen. Simultaneously, WCA induced an increase in total phenolic, flavanone and dihydroflavonol, flavone and flavonol, and lignin contents. Thus, our results suggest that treatment using 5250 mg CA/L wax can be applied early to control diseases by provoking response reactions in citrus fruit.


Assuntos
Citrus , Penicillium , Acroleína/análogos & derivados , Geotrichum , Doenças das Plantas
5.
Enzyme Microb Technol ; 152: 109938, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34753033

RESUMO

Hydrolytic enzymes are highly demanded in the industry. Thermostability is an important property of enzymes that affects the economic costs of the industrial processes. The rational design of GH10 xylanase E (XylE) Penicillium canescens for the thermostability improvement was directed by ΔΔG calculations and structure analysis. Amino acid substitutions with stabilizing values of ΔΔG and providing an increase in side-chain volume of buried residues were performed experimentally. From the six designed substitutions, four substitutions appeared to be stabilizing, one - destabilizing, and one - neutral. For the improved XylE variants, values of Tm were increased by 1.1-3.1 °C, and times of half-life at 70 °C were increased in 1.3-1.7-times. Three of the four stabilizing substitutions were located in the N- or the C-terminus region. This highlights the importance of N- and C-terminus for the thermostability of GH10 xylanases and also enzymes with (ß/α)8 TIM barrel type of structure. The criteria of stabilizing values of ΔΔG and increased side-chain volume of buried residues for selection of substitutions may be applied in the rational design for thermostability improvement.


Assuntos
Penicillium , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Penicillium/genética , Penicillium/metabolismo , Temperatura
6.
J Nanosci Nanotechnol ; 21(6): 3556-3565, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739807

RESUMO

Plant-derived essential oils and extracts are known to be effective against many microorganisms. The essential oil obtained from fresh leaves of Ocimum gratissimum possessed promising antifungal activity against Penicillium digitatum. The antifungal potential of O. gratissimum essential oil can be markedly improved with the use of nanotechnology. O. gratissimum essential oil based nanoformulations were prepared using non-ionic surfactant and water by ultrasonication. The process was optimized for parameters such as surfactant concentration and sonication time to achieve minimum droplet diameter with high physical stability. Stable O. gratissimum essential oil nanoemulsions were obtained for 1:1 ratio (v/v) of essential oil and surfactant with mean droplet diameter of 259.4 nm for 10 min sonication time. Essential oil and all nanoemulsions were evaluated for their antifungal activity against P. digitatum of kinnow fruit by poisoned food technique. The nanoemulsion (1:1, 10 min) showed the highest growth inhibition (1 × 104 CFU ml-1, 96%) against P. digitatum followed by pure oil (13 × 104 CFU ml-1, 85%) on 15th day of incubation. Scanning electron and optical microscopy results further revealed stronger suppressive activity of O. gratissimum essential oil nanoemulsions for spore germination and hyphal elongation of P. digitatum than pure oil.


Assuntos
Ocimum , Óleos Voláteis , Penicillium , Antifúngicos/farmacologia , Óleos Voláteis/farmacologia
7.
J Environ Sci (China) ; 109: 148-160, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607663

RESUMO

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.


Assuntos
Desinfetantes , Água Subterrânea , Penicillium , Purificação da Água , Biofilmes , Cloro , Fungos , Humanos , Hypocreales , Cinética
8.
Appl Microbiol Biotechnol ; 105(21-22): 8157-8193, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34625822

RESUMO

Quinones represent an important group of highly structurally diverse, mainly polyketide-derived secondary metabolites widely distributed among filamentous fungi. Many quinones have been reported to have important biological functions such as inhibition of bacteria or repression of the immune response in insects. Other quinones, such as ubiquinones are known to be essential molecules in cellular respiration, and many quinones are known to protect their producing organisms from exposure to sunlight. Most recently, quinones have also attracted a lot of industrial interest since their electron-donating and -accepting properties make them good candidates as electrolytes in redox flow batteries, like their often highly conjugated double bond systems make them attractive as pigments. On an industrial level, quinones are mainly synthesized from raw components in coal tar. However, the possibility of producing quinones by fungal cultivation has great prospects since fungi can often be grown in industrially scaled bioreactors, producing valuable metabolites on cheap substrates. In order to give a better overview of the secondary metabolite quinones produced by and shared between various fungi, mainly belonging to the genera Aspergillus, Penicillium, Talaromyces, Fusarium, and Arthrinium, this review categorizes quinones into families such as emodins, fumigatins, sorbicillinoids, yanuthones, and xanthomegnins, depending on structural similarities and information about the biosynthetic pathway from which they are derived, whenever applicable. The production of these quinone families is compared between the different genera, based on recently revised taxonomy. KEY POINTS: • Quinones represent an important group of secondary metabolites widely distributed in important fungal genera such as Aspergillus, Penicillium, Talaromyces, Fusarium, and Arthrinium. • Quinones are of industrial interest and can be used in pharmacology, as colorants and pigments, and as electrolytes in redox flow batteries. • Quinones are grouped into families and compared between genera according to the revised taxonomy.


Assuntos
Fusarium , Penicillium , Talaromyces , Aspergillus , Fungos , Humanos , Quinonas
9.
Ecotoxicol Environ Saf ; 227: 112880, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34655883

RESUMO

Phosphorus (P) containing minerals are identified as effective Pb stabilizers in soil, while their low solubility limit the Pb immobilization efficiency. In this work, the combination of phosphate solubilizing fungi (PSF) Penicillium oxalicum and tricalcium phosphate (TCP) was constructed and applied to improve Pb immobilization stabilities in medium and soils. P. oxalicum+ TCP could significantly improve Pb2+ removal to above 99% under different TCP/Pb2+ and pH values. TCP and P. oxalicum could remarkably immobilize Pb by ion exchange, and PbC2O4 precipitation or surface adsorption, respectively. While the enhanced Pb immobilization in P. oxalicum+ TCP was explained by stronger Pb2+ interaction with tryptophan protein-like substances in extracellular polymeric substance, and the formation of the most stable Pb-phosphate compound hydroxypyromorphite (Pb5(PO4)3OH). Toxicity characteristic leaching procedure test showed that only 0.91% of Pb2+ was leachable in P. oxalicum+ TCP treatment, significantly lower than that in P. oxalicum (2.90%) and TCP (7.52%) treatments. In addition, the lowest soil exchangeable Pb fraction (37.1%) and the highest available soil P (88.0 mg/kg) were both found in P. oxalicum+ TCP treatment. By synergistically forming stable Pb-containing products, thus the combination of PSF and P minerals could significantly improve Pb2+ immobilization and stability in soils.


Assuntos
Penicillium , Poluentes do Solo , Fosfatos de Cálcio , Matriz Extracelular de Substâncias Poliméricas/química , Chumbo , Fosfatos/análise , Solo , Poluentes do Solo/análise
10.
Environ Sci Process Impacts ; 23(11): 1681-1687, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34596193

RESUMO

Indoor flooding is a leading contributor to indoor dampness and the associated mold infestations in the coastal United States. Whether the prevalent mold genera that infest the coastal flood-prone buildings are different from those not flood-prone is unknown. In the current case study of 28 mold-infested buildings across the U.S. east coast, we surprisingly noted a trend of higher prevalence of indoor Aspergillus and Penicillium genera (denoted here as Asp-Pen) in buildings with previous flooding history. Hence, we sought to determine the possibility of a potential statistically significant association between indoor Asp-Pen prevalence and three building-related variables: (i) indoor flooding history, (ii) geographical location, and (iii) the building's use (residential versus non-residential). Culturable spores and hyphal fragments in indoor air were collected using the settle-plate method, and corresponding genera were confirmed using phylogenetic analysis of their ITS sequence (the fungal barcode). Analysis of variance (ANOVA) using Generalized linear model procedure (GLM) showed that Asp-Pen prevalence is significantly associated with indoor flooding as well as coastal proximity. To address the small sample size, a multivariate decision tree analysis was conducted, which ranked indoor flooding history as the strongest determinant of Asp-Pen prevalence, followed by geographical location and the building's use.


Assuntos
Poluição do Ar em Ambientes Fechados , Penicillium , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise , Aspergillus , Inundações , Fungos , Filogenia , Prevalência
11.
Arch Microbiol ; 203(10): 6091-6108, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34609530

RESUMO

Five filamentous fungal strains that grew in different whey-based media under submerged fermentation were investigated for antioxidant properties and phytochemicals. Phytochemical analysis revealed the presence of alkaloids, tannin, flavonoids, glycosides, phenols, saponins, and terpenes in the crude intra- and extracellular ethyl acetate extracts of different strains. All fungal extracts exhibited effective antioxidant activities in terms of TPC, TFC, DPPH, FRAP, ABTS, reducing power, and metal chelating capacity. The activities of intracellular extracts were higher than the extracellular metabolites. Fermentation media with sugar and salt supplementation significantly influenced antioxidant production. Aspergillus niger in glucose-supplemented whey medium was found to exhibit the highest antioxidant properties. The antimicrobial activity of A. niger and Penicillium expansum extracts by microtiter plate assay showed a promising result against some pathogenic bacterial strains. Chromatographic analysis of the fungal extracts revealed the presence of chlorogenic acid, trans-cinnamic acid, ferulic acid quercetin, myricetin, kaempferol, and catechin which are known for their antioxidant properties. Accumulation of nutrients in fungal biomass under constraint environment produces secondary metabolites which has demonstrated efficacy towards alleviation of several degenerative diseases. The antioxidative enriched phytochemicals present in these five different fungal strains will provide a breakthrough in the utilisation of whey as inexpensive source of substrate for the growth of these fungi. Moreover, phytochemicals could be utilized as therapeutic agents in a cost-effective and environmentally friendly manner.


Assuntos
Anti-Infecciosos , Antioxidantes , Antioxidantes/farmacologia , Fungos , Penicillium , Compostos Fitoquímicos/farmacologia , Extratos Vegetais
12.
Biomolecules ; 11(9)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34572579

RESUMO

SARS-CoV-2 virus mutations might increase its virulence, and thus the severity and duration of the ongoing pandemic. Global drug discovery campaigns have successfully developed several vaccines to reduce the number of infections by the virus. However, finding a small molecule pharmaceutical that is effective in inhibiting SARS-CoV-2 remains a challenge. Natural products are the origin of many currently used pharmaceuticals and, for this reason, a library of in-house fungal extracts were screened to assess their potential to inhibit the main viral protease Mpro in vitro. The extract of Penicillium citrinum, TDPEF34, showed potential inhibition and was further analysed to identify potential Mpro inhibitors. Following bio-guided isolation, a series of benzodiazepine alkaloids cyclopenins with good-to-moderate activity against SARS-CoV-2 Mpro were identified. The mode of enzyme inhibition of these compounds was predicted by docking and molecular dynamic simulation. Compounds 1 (isolated as two conformers of S- and R-isomers), 2, and 4 were found to have promising in vitro inhibitory activity towards Mpro, with an IC50 values range of 0.36-0.89 µM comparable to the positive control GC376. The in silico investigation revealed compounds to achieve stable binding with the enzyme active site through multiple H-bonding and hydrophobic interactions. Additionally, the isolated compounds showed very good drug-likeness and ADMET properties. Our findings could be utilized in further in vitro and in vivo investigations to produce anti-SARS-CoV-2 drug candidates. These findings also provide critical structural information that could be used in the future for designing potent Mpro inhibitors.


Assuntos
Proteases 3C de Coronavírus , Inibidores de Cisteína Proteinase , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Penicillium/química , SARS-CoV-2/enzimologia , Benzodiazepinonas/química , Benzodiazepinonas/isolamento & purificação , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/isolamento & purificação
13.
Food Res Int ; 148: 110610, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507754

RESUMO

Different strains of a given fungal species may display heterogeneous growth behavior in response to environmental factors. In predictive mycology, the consideration of such variability during data collection could improve the robustness of predictive models. Among food-borne fungi, Penicillium roqueforti is a major food spoiler species which is also used as a ripening culture for blue cheese manufacturing. In the present study, we investigated the intraspecific variability of cardinal temperatures and water activities (aw), namely, minimal (Tmin and awmin), optimal (Topt and awopt) and maximal (Tmax) temperatures and/or aw estimated with the cardinal model for radial growth, of 29 Penicillium roqueforti strains belonging to 3 genetically distinct populations. The mean values of cardinal temperatures and aw for radial growth varied significantly across the tested strains, except for Tmax which was constant. In addition, the relationship between the intraspecific variability of the biological response to temperature and aw and putative genetic populations (based on microsatellite markers) within the selected P. roqueforti strains was investigated. Even though no clear relationship was identified between growth parameters and ecological characteristics, PCA confirmed that certain strains had marginal growth response to temperature or aw. Overall, the present data support the idea that a better knowledge of the response to abiotic factors such as temperature and aw at an intraspecific level would be useful to model fungal growth in predictive mycology approaches.


Assuntos
Penicillium , Microbiologia de Alimentos , Penicillium/genética , Temperatura , Água
14.
Int J Food Microbiol ; 357: 109385, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34509930

RESUMO

This study was conducted to determine the diversity of yeasts and filamentous moulds in mould-matured cheese (MMC) consumed in Turkey. Overall, 120 samples were collected from 12 different geographical locations between March 2016 and April 2017. The morphological observation was applied in combination with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and molecular analyses to determine yeasts and filamentous moulds in the cheeses. High-performance liquid chromatography (HPLC) technique was used to evaluate the ability of mycotoxins production of fungal isolates and the presence of mycotoxins in cheese samples. A total of 241 fungi (81 filamentous moulds and 160 yeast) were recovered, and Penicillium roqueforti and Debaryomyces hansenii were the most frequently isolated species in all cheese samples. The rep-PCR results indicated a high level of genetic diversity among fungal isolates, regardless of isolation source or geographical origin. Filamentous mould strains isolated from MMC were found to synthesize at least one mycotoxin (Aflatoxin B1, B2, G1 and G2, citrinine, cyclopiazonic acid, mycophenolic acid, ochratoxin A, penicillic acid and roquefortine C). Although mycotoxin producing ability was observed from all isolates, none of the cheese samples were found positive for these mycotoxins. AFM1 was detected in 8 (6.6%) MMC samples from which 2 (1.6%) were above the legal limits (0.05 µg/kg) set by the Turkish Food Codex (TFC) and European Commission (EC). In conclusion, Turkish MMCs were found to be contaminated with toxigenic fungi, so a potential public health risk, while low, exists. Therefore, the selection of nontoxigenic filamentous mould strains for cheese manufacturing and control of the ripening conditions is a critical need to ensure the quality and safety of Turkish MMC.


Assuntos
Queijo , Micotoxinas , Microbiologia de Alimentos , Fungos/genética , Micotoxinas/análise , Penicillium , Filogenia , Turquia
15.
Appl Microbiol Biotechnol ; 105(20): 7731-7741, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34568964

RESUMO

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.


Assuntos
Aspergillus niger , Iridoides , Aspergillus , Biotransformação , Glucosídeos Iridoides , Penicillium
16.
Arch Microbiol ; 203(10): 5975-5992, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34535810

RESUMO

Airborne fungi are one of the major components of aeromycobiota known to produce several fungal diseases in fruits. Their presence in indoor environment of warehouses may limit the storage period of apples. Qualitative and quantitative analyses of airborne fungal spores were conducted using gravity settling techniques to detect fungal airspora present in the atmosphere of two apple warehouses in Tunisia. In this study, 375 fungal isolates were obtained and purified. Phylogenetic analysis of calmodulin, beta-tubulin and ITS regions coupled with phenotypic characterization helped to identify 15 fungal species. Penicillium exhibited the highest diversity with ten species detected (Penicillium allii, P. chrysogenum, P. citrinum, P. expansum, P. italicum, P. polonicum, P. solitum, P. steckii, P. sumatraense and P. viridicatum), followed by four species of Aspergillus genus (Aspergillus europaeus, A. flavus, A. niger and A. pulverulentus) and Alternaria alternata. In vivo experiments confirmed the pathogenicity of 13 species at room temperature and under cold-storage conditions. Among them, A. europaeus, A. pulverulentus, P. allii and P. sumatraense were described for the first time as pathogens on apples. The present study identified the major airborne fungi associated with postharvest rot in apple storage facilities in Tunisia and may help in efficient control of postharvest and storage fruit diseases.


Assuntos
Poluição do Ar , Malus , Penicillium , Alternaria , Aspergillus/genética , Penicillium/genética , Filogenia
17.
Sci Rep ; 11(1): 17861, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504186

RESUMO

The enzyme L-asparaginase (L-ASNase) is used in the treatment of Acute Lymphoblastic Leukemia. The preparations of this enzyme for clinical use are derived from bacterial sources and its use is associated with serious adverse reactions. In this context, it is important to find new sources of L-ASNase. In this work, the Placket-Burman Experimental Design (PBD) was used to determine the influence of the variables on the L-ASNase production then it was followed by a 28-4 Factorial Fractional Design (FFD). The results obtained from PBD have shown a range of L-ASNase activity, from 0.47 to 1.77 U/gcell and the results obtained from FFD have showed a range of L-ASNase activity, from 1.10 to 2.36 U/gcell. L-proline and ammonium sulfate were identified as of significant positive variables on this production enzyme by Penicillium cerradense sp. nov. The precise identification of this new species was confirmed by morphological characteristics and sequence comparisons of the nuclear 18S-5.8S-28S partial nrDNA including the ITS1 and ITS2 regions, RNA polymerase II, ß-tubulin and calmodulin genomic regions. The genetic sequence coding for the L-ASNase was obtained after carrying out a full genome sequencing. The L-ASNase expressed by P. cerradense sp. nov may have promising antineoplastic properties.


Assuntos
Antineoplásicos/uso terapêutico , Asparaginase/genética , Penicillium/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Prolina/genética , Asparaginase/uso terapêutico , Humanos , Penicillium/metabolismo , Prolina/uso terapêutico , Análise de Sequência de DNA/métodos
19.
Food Res Int ; 147: 110582, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399551

RESUMO

Fungal contamination is among the main reasons for food spoilage, affecting food safety and the economy. Among fungi, Penicillium digitatum is a major agent of this problem. Here, the in vitro activity of eight synthetic antimicrobial peptides was assessed against P. digitatum, and their action mechanisms were evaluated. All peptides were able to inhibit fungal growth. Furthermore, atomic force and fluorescence microscopies revealed that all peptides targeted the fungal membrane leading to pore formation, loss of internal content, and death. The induction of high levels of reactive oxygen species (ROS) was also a mechanism employed by some peptides. Interestingly, only three peptides (PepGAT, PepKAA, and Mo-CBP3-PepI) effectively control P. digitatum colonization in orange fruits, at a concentration (50 µg mL-1) 20-fold lower than the commercial food preservative (sodium propionate). Altogether, PepGAT, PepKAA, and Mo-CBP3-PepI showed high biotechnological potential as new food preservatives to control food infection by P. digitatum.


Assuntos
Citrus sinensis , Penicillium , Frutas , Proteínas Citotóxicas Formadoras de Poros
20.
Molecules ; 26(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361698

RESUMO

Patulin (PAT) and citrinin (CTN) are the most common mycotoxins produced by Penicillium and Aspergillus species and are often associated with fruits and fruit by-products. Hence, simple and reliable methods for monitoring these toxins in foodstuffs are required for regular quality assessment. In this study, we aimed to establish a cost-effective method for detection and quantification of PAT and CTN in pome fruits, such as apples and pears, using high-performance liquid chromatography (HPLC) coupled with spectroscopic detectors without the need for any clean-up steps. The method showed good performance in the analysis of these mycotoxins in apple and pear fruit samples with recovery ranges of 55-97% for PAT and 84-101% for CTN, respectively. The limits of detection (LOD) of PAT and CTN in fruits were 0.006 µg/g and 0.001 µg/g, while their limits of quantification (LOQ) were 0.018 µg/g and 0.003 µg/g, respectively. The present findings indicate that the newly developed HPLC method provides rapid and accurate detection of PAT and CTN in fruits.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citrinina/análise , Contaminação de Alimentos/análise , Frutas/química , Malus/química , Patulina/análise , Pyrus/química , Aspergillus/metabolismo , Cromatografia Líquida de Alta Pressão/economia , Análise Custo-Benefício , Confiabilidade dos Dados , Qualidade dos Alimentos , Limite de Detecção , Penicillium/metabolismo , Fatores de Tempo
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