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Brazilian Journal of Microbiology :... 2018The presence of mycotoxins or related fungi in animal feed is a major problem for animal and human health. Silage and concentrated feed samples were collected from 21...
The presence of mycotoxins or related fungi in animal feed is a major problem for animal and human health. Silage and concentrated feed samples were collected from 21 dairy farms in the Western part of Paraná state in Southern Brazil. Water activity and pH of all samples were measured, and each sample was analyzed to check for the presence of aflatoxigenic Aspergillus. Water activity was observed to be lower in the concentrated feed samples. The pH was lower in the silage samples, indicating fermentation processes. Two silage samples and four concentrated feed samples were contaminated with Aspergillus spp. Seven isolates of Aspergillus spp. were obtained and their potential to produce aflatoxins was evaluated. Four of the isolates, two from the silage samples and two from the concentrated feed samples, produced the aflatoxins B1, B2, G1, and G2 in culture media. These isolates were identified as Aspergillus parasiticus and Aspergillus nomius. The presence of aflatoxigenic isolates of Aspergillus spp. in silage and concentrated feed samples is a matter of concern, because of the risk of aflatoxin production and contamination of the animal feed.
Topics: Aflatoxins; Animal Feed; Animals; Aspergillus; Brazil; Cattle; Food Contamination; Silage
PubMed: 30174202
DOI: 10.1016/j.bjm.2018.05.005 -
Journal of Food Protection May 2014The genus Aspergillus section Nigri, or the black aspergilli, represents genetically closely related species that produce the mycotoxins, ochratoxins and the fumonisins....
The genus Aspergillus section Nigri, or the black aspergilli, represents genetically closely related species that produce the mycotoxins, ochratoxins and the fumonisins. Fumonisin B1 (FB1) is of an added concern because it is also a virulence factor for maize. Our preliminary data indicated that black aspergilli could develop asymptomatic infections with maize and peanuts plants. Symptomless infections are potential problems, because under favorable conditions, there is a potential for accumulation of ochratoxins and the fumonisins in contaminated postharvest crops. In the present report, the ability of black aspergilli from peanuts and maize to produce ochratoxin A and FB1 on maize kernels was assessed. One hundred fifty strains from peanuts and maize were isolated from several southeastern and midwestern states. Aspergillus nigri (A. nigri var. nigri) was the dominant species (87%), while Aspergillus foetidus, Aspergillus japonicus, Aspergillus tubingensis, and Aspergillus carbonarius were infrequently isolated. None of the wild isolates produced detectable amounts of ochratoxins. However, we do report the occurrence of the fumonisins B1, B2, and B3. Of 54 field isolates, 30% (n = 16) produced FB1, 61% (n = 33) produced FB2, and 44% (n = 24) produced FB3. The amounts of fumonisins produced during the test period of 30 days suggest that these strains might be weak to moderate producers of fumonisin on maize. To our knowledge, this is a first report of FB1 and FB3 production by isolates of black aspergilli from an American cereal and legume.
Topics: Arachis; Aspergillus; Food Contamination; Fumonisins; Mycotoxins; Ochratoxins; Zea mays
PubMed: 24780336
DOI: 10.4315/0362-028X.JFP-13-321 -
Journal of Medicine and Life 2019species (sp.) that causes opportunistic infections have been increasingly found in human mainly immunosuppressive patients around the world every year. The main...
species (sp.) that causes opportunistic infections have been increasingly found in human mainly immunosuppressive patients around the world every year. The main objective was to use a rapid and cheap molecular method for monitoring infections and epidemiological approaches. In order to identity species (spp.), a number of molecular methods including restriction fragment length polymorphism (RFLP) have been employed in accordance with ribosomal RNA amplification. The focus of this study - a group of hospitalized patients with clinical and subclinical signs of infection. All of the collected clinical specimens were transported to the medical mycology lab and examined for identification. The environmental specimens were collected from air and surfaces inspected for the within the hospital sources. At first, growth characteristics and microscopic features on mycological media for the identification of sp. were performed. For the confirmation of isolates which similarly found in clinical and environmental sources, molecular method polymerase chain reaction/restriction fragment length polymorphism was carried out. From the mentioned specimens, 102 fungal isolates included spp., spp. and other fungi. (47%), (29.4%) and (23.5%) all were found as the most common clinical isolates. In addition, isolates from environmental were (43.7%), (41.7%), (14.6%). Therefore, polymerase chain reaction-restriction fragment length polymorphism with a single restriction enzyme can be very useful in the identification of spp., because of its facility in use, speed, robust, and high sensitivity of diagnosis.
Topics: Aspergillosis; Aspergillus; Cross Infection; Environment; Hospitals, University; Humans; Polymorphism, Restriction Fragment Length
PubMed: 31406513
DOI: 10.25122/jml-2018-0057 -
Viruses Oct 2018This study determined the effects of chrysovirus 1 (AthCV1), isolated from on , and Protoplasts of virus-free isolates of , and were transfected with purified...
This study determined the effects of chrysovirus 1 (AthCV1), isolated from on , and Protoplasts of virus-free isolates of , and were transfected with purified AthCV1 particles and the phenotype, growth and sporulation of the isogenic AthCV1-free and AthCV1-infected lines assessed at 20 °C and 37 °C and gene expression data collected at 37 °C. AthCV1-free and AthCV1-infected produced only conidia at both temperatures but more than ten-fold reduced compared to the AthCV1-infected line. Conidiation was also significantly reduced in infected lines of and at 37 °C. AthCV1-infected lines of and produced large numbers of ascospores at both temperatures, whereas the AthCV1-free line of the former did not produce ascospores. AthCV1-infected lines of all species developed sectoring phenotypes with sclerotia produced in aconidial sectors of at 37 °C. AthCV1 was detected in 18% of sclerotia produced by AthCV1-infected and 31% of ascospores from AthCV1-infected Transcriptome analysis of the naturally AthCV1-infected and the three AthCV1-transfected species showed altered gene expression as a result of AthCV1-infection. The results demonstrate that AthCV1 can infect a range of species resulting in reduced sporulation, a potentially useful attribute for a biological control agent.
Topics: Aspergillus; Biological Control Agents; Fungal Viruses; Gene Expression Profiling; Gene Expression Regulation, Fungal; Phenotype; RNA Viruses; Spores, Fungal; Temperature
PubMed: 30279352
DOI: 10.3390/v10100539 -
Bioresource Technology Sep 2023In this study, α-L-arabinofuranosidase (AF) from Aspergillus awamori was heterologously expressed in Pichia pastoris X33, with a 1-fold increase in AF activity after...
In this study, α-L-arabinofuranosidase (AF) from Aspergillus awamori was heterologously expressed in Pichia pastoris X33, with a 1-fold increase in AF activity after codon and vector optimization. AF remained stable at 60-65 °C and displayed a broad pH stability range of 2.5-8.0. It also demonstrated considerable resistance to pepsin and trypsin. Furthermore, compared with xylanase alone, AF with xylanase exhibited a marked synergistic effect in the degradation of expanded corn bran, corn bran, and corn distillers' dried grains with solubles, reducing sugars by 3.6-fold, 1.4-fold, and 6.5-fold, respectively, with the degree of synergy increasing to 4.61, 2.44, and 5.4, respectively, while in vitro dry matter digestibility values were 17.6%, 5.2%, and 8.8%, respectively. After enzymatic saccharification, corn byproducts were converted to prebiotic xylo-oligosaccharides and arabinoses, thereby demonstrating the favorable properties of AF in the degradation of corn biomass and its byproducts.
Topics: Zea mays; Glycoside Hydrolases; Aspergillus
PubMed: 37290707
DOI: 10.1016/j.biortech.2023.129278 -
Toxins Jan 2020Aflatoxins (AF) are highly toxic compounds produced by section . They spoil food crops and present a serious global health hazard to humans and livestock. The aim of...
Aflatoxins (AF) are highly toxic compounds produced by section . They spoil food crops and present a serious global health hazard to humans and livestock. The aim of this study was to examine the phylogenetic relationships among aflatoxigenic and non-aflatoxigenic isolates. A polyphasic approach combining phylogenetic, sequence, and toxin analyses was applied to 40 section isolates collected from eight countries around the world (USA, Philippines, Egypt, India, Australia, Indonesia, China, and Uganda). This allows one to pinpoint the key genomic features that distinguish AF producing and non-producing isolates. Based on molecular identification, 32 (80%) were identified as three (7.5%) as three (7.5%) as and one (2.5%) as Toxin analysis showed that 22 (55%) isolates were aflatoxigenic. The majority of the toxic isolates (62.5%) originated from Egypt. The highest aflatoxin production potential was observed in an isolate which is originally isolated from the Philippines. DNA-based molecular markers such as random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) were used to evaluate the genetic diversity and phylogenetic relationships among these 40 isolates, which were originally selected from 80 isolates. The percentage of polymorphic bands in three RAPD and three ISSR primers was 81.9% and 79.37%, respectively. Analysis of molecular variance showed significant diversity within the populations, 92% for RAPD and 85% for ISSR primers. The average of Polymorphism Information Content (PIC), Marker Index (MI), Nei's gene diversity (H) and Shannon's diversity index (I) in ISSR markers are higher than those in RAPD markers. Based on banding patterns and gene diversities values, we observed that the ISSR-PCR provides clearer data and is more successful in genetic diversity analyses than RAPD-PCR. Dendrograms generated from UPGMA (Unweighted Pair Group Method with Arithmetic Mean) cluster analyses for RAPD and ISSR markers were related to the geographic origin.
Topics: Aflatoxins; Aspergillus; Aspergillus flavus; Australia; China; DNA Primers; Egypt; Genetic Variation; Genomics; Microsatellite Repeats; Phylogeny; Polymerase Chain Reaction; Polymorphism, Genetic; Random Amplified Polymorphic DNA Technique; Uganda
PubMed: 31963352
DOI: 10.3390/toxins12010056 -
Bioengineered 2014Itaconic acid is an important building block for the chemical industry. Currently, Aspergillus terreus is the main organism used for itaconic acid production. Due to the...
Itaconic acid is an important building block for the chemical industry. Currently, Aspergillus terreus is the main organism used for itaconic acid production. Due to the enormous citric acid production capacity of Aspergillus niger, this host is investigated as a potential itaconic acid production host. Several strategies have been tried so far: fermentation optimization, expression of cis-aconitate decarboxylase (cadA) alone and in combination with aconitase targeted to the same compartment, chassis optimization, and the heterologous expression of two transporters flanking the cadA gene. We showed that the heterologous expression of these two transporters were key to improving itaconic acid production in an A. niger strain that was unable to produce oxalic acid and gluconic acid. The expression of transporters has increased the production levels of other industrially relevant processes as well, such as β-lactam antibiotics and bioethanol. Thus far, the role of transporters in production process optimization is a bit overlooked.
Topics: Aspergillus; Aspergillus niger; Carboxy-Lyases; Fungal Proteins; Succinates
PubMed: 25482236
DOI: 10.4161/bioe.29936 -
Veterinary Microbiology Mar 2014Stonebrood is a disease of honey bee larvae caused by fungi from the genus Aspergillus. As very few studies have focused on the epidemiological aspects of stonebrood and...
Stonebrood is a disease of honey bee larvae caused by fungi from the genus Aspergillus. As very few studies have focused on the epidemiological aspects of stonebrood and diseased brood may be rapidly discarded by worker bees, it is possible that a high number of cases go undetected. Aspergillus spp. fungi are ubiquitous and associated with disease in many insects, plants, animals and man. They are regarded as opportunistic pathogens that require immunocompromised hosts to establish infection. Microbiological studies have shown high prevalences of Aspergillus spp. in apiaries which occur saprophytically on hive substrates. However, the specific conditions required for pathogenicity to develop remain unknown. In this study, an apiary was screened to determine the prevalence and diversity of Aspergillus spp. fungi. A series of dose-response tests were then conducted using laboratory reared larvae to determine the pathogenicity and virulence of frequently occurring isolates. The susceptibility of adult worker bees to Aspergillus flavus was also tested. Three isolates (A. flavus, Aspergillus nomius and Aspergillus phoenicis) of the ten species identified were pathogenic to honey bee larvae. Moreover, adult honey bees were also confirmed to be highly susceptible to A. flavus infection when they ingested conidia. Neither of the two Aspergillus fumigatus strains used in dose-response tests induced mortality in larvae and were the least pathogenic of the isolates tested. These results confirm the ubiquity of Aspergillus spp. in the apiary environment and highlight their potential to infect both larvae and adult bees.
Topics: Animals; Aspergillus; Bees; Biodiversity; DNA, Ribosomal Spacer; Larva; Survival Analysis
PubMed: 24485932
DOI: 10.1016/j.vetmic.2013.11.029 -
The Journal of General and Applied... Sep 2020Naturally occurring fungi have been used in the traditional production of dried bonito, Katsuobushi, in Japan. In this study, we analyzed the fungal population present...
Naturally occurring fungi have been used in the traditional production of dried bonito, Katsuobushi, in Japan. In this study, we analyzed the fungal population present during Katsuobushi production. Amplicon sequence analysis of ITS1 indicated that Aspergillus spp. are predominant throughout the production process. In addition, culture-dependent analyzes identified three species Aspergillus chevalieri, Aspergillus montevidensis, and Aspergillus sydowii, based on sequencing of benA, caM, and rpb2 genes. A. chevalieri isolates were classified into teleomorphic and anamorphic strains based on morphological analysis. A. chevarieri was the dominant species throughout the production process, whereas A. montevidensis increased and A. sydowii decreased in abundance during Katsuobushi production. Our study will enhance the understanding of fungal species involved in traditional Katsuobushi production.
Topics: Aspergillus; DNA, Fungal; Fish Products; Food Microbiology; Japan; Phylogeny; Sequence Analysis, DNA
PubMed: 32009019
DOI: 10.2323/jgam.2019.09.003 -
Antimicrobial Agents and Chemotherapy Jan 2017Method-dependent Etest epidemiological cutoff values (ECVs) are not available for susceptibility testing of either Candida or Aspergillus species with amphotericin B or...
Multicenter Study of Method-Dependent Epidemiological Cutoff Values for Detection of Resistance in Candida spp. and Aspergillus spp. to Amphotericin B and Echinocandins for the Etest Agar Diffusion Method.
Method-dependent Etest epidemiological cutoff values (ECVs) are not available for susceptibility testing of either Candida or Aspergillus species with amphotericin B or echinocandins. In addition, reference caspofungin MICs for Candida spp. are unreliable. Candida and Aspergillus species wild-type (WT) Etest MIC distributions (microorganisms in a species-drug combination with no detectable phenotypic resistance) were established for 4,341 Candida albicans, 113 C. dubliniensis, 1,683 C. glabrata species complex (SC), 709 C. krusei, 767 C. parapsilosis SC, 796 C. tropicalis, 1,637 Aspergillus fumigatus SC, 238 A. flavus SC, 321 A. niger SC, and 247 A. terreus SC isolates. Etest MICs from 15 laboratories (in Argentina, Europe, Mexico, South Africa, and the United States) were pooled to establish Etest ECVs. Anidulafungin, caspofungin, micafungin, and amphotericin B ECVs (in micrograms per milliliter) encompassing ≥97.5% of the statistically modeled population were 0.016, 0.5, 0.03, and 1 for C. albicans; 0.03, 1, 0.03, and 2 for C. glabrata SC; 0.06, 1, 0.25, and 4 for C. krusei; 8, 4, 2, and 2 for C. parapsilosis SC; and 0.03, 1, 0.12, and 2 for C. tropicalis The amphotericin B ECV was 0.25 μg/ml for C. dubliniensis and 2, 8, 2, and 16 μg/ml for the complexes of A. fumigatus, A. flavus, A. niger, and A. terreus, respectively. While anidulafungin Etest ECVs classified 92% of the Candida fks mutants evaluated as non-WT, the performance was lower for caspofungin (75%) and micafungin (84%) cutoffs. Finally, although anidulafungin (as an echinocandin surrogate susceptibility marker) and amphotericin B ECVs should identify Candida and Aspergillus isolates with reduced susceptibility to these agents using the Etest, these ECVs will not categorize a fungal isolate as susceptible or resistant, as breakpoints do.
Topics: Amphotericin B; Antifungal Agents; Aspergillus; Candida; Disk Diffusion Antimicrobial Tests; Drug Resistance, Fungal; Echinocandins; Europe; Latin America; South Africa; United States
PubMed: 27799206
DOI: 10.1128/AAC.01792-16