scholarly journals Aspergillus niger as the Source of Ochratoxin A of Contaminated Pyrus communis in Taif Market

2019 ◽  
pp. 1-9
Author(s):  
Yassmin M. Shebany ◽  
Youssuf A. Gherbawy ◽  
Shoroug N. Al-Garni
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Biosynthetic Pathway ◽  
Pyrus Communis ◽  
The Body ◽  
Agricultural Products ◽  
Essential Minerals ◽  
Black Aspergilli ◽  
Different Strains ◽  
And Storage

Fruits are one of the most important agricultural products that supply the body with vitamins and essential minerals elements, but it is contaminated by fungi during the period of growth, harvesting and storage. A. niger is one of the species that grows on the fruit during the period of storage, and secretes mycotoxins especially ochratoxin A. This study was conducted with the purpose of isolating  and identifying different strains of A. niger from 20 samples of pear collected from Taif markets and to determine the ability of these strains to produce OTA. It was observed that showed that out of 20 pear samples collected, 19 samples were detected to be contaminated with different strains of A. niger and the strains were able to produce OTA. From 27 isolates of A. niger which was  used to test the ability of production OTA, 10 strains only produced OTA. The range of OTA in all strains were 0.18 to 9.5 ppb. Representative 27 strains of ochratoxigenic and non ochratoxigenic black Aspergilli isolated were subjected for detection of ochratoxin biosynthesis genes, by using  two sets of primer for two genes involved in ochratoxin biosynthetic pathway. Bands of the fragments of PKS15C-MeT and PKS15KS genes visualized at 998 and 776 bp, respectively. Whereas, the presence of four tested genes is not sufficient marker for differentatin between aflatoxigenic and non aflatoxigenic isolates.

scholarly journals Morphological and Molecular Characterization of Ochratoxin A Producing Black Aspergilli from Grape Pomace

2015 ◽  
Vol 4 (5) ◽  
pp. 39 ◽  
Author(s):  
Bernice Karlton-Senaye ◽  
Jianmei Yu ◽  
Leonard Williams
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Random Amplified Polymorphic Dna ◽  
Fungal Species ◽  
Grape Pomace ◽  
Fungal Population ◽  
Food Ingredients ◽  
Black Aspergilli ◽  
By Products ◽  
Grape Cultivars

Grape pomace (GP), a winery by-product is increasingly being explored as food ingredients. Ochratoxin A (OTA), a natural toxigenic metabolite frequently found in wine and its by-products. Black Aspergilli<em> </em>are mainly responsible for OTA build-up and contamination of grapes and winery by-products. The fungal population in GP of five grape cultivars were enumerated and characterized. Fungal population ranged from 4.27±0.05 to 5.35±0.04 Log CFU/mL with GP from Chardonnay being the most contaminated.<em> Aspergillus niger</em> (81.1%) was found to be the major source of contamination and most frequently isolated fungal species. Other fungal isolates were <em>A. carbonarius </em>(13.51%) and <em>A fumigatus </em>(5.39%). Fungal contamination of GP correlated with the type of grape cultivars used for the pomace. Fourteen identified mold isolates were confirmed by PCR using primer pairs ITS1/NIG, ITS1/CAR and ITS1/FUM. Random amplified polymorphic DNA (RAPD) analysis with eight primers OPC-04, OPC-06, OPC-08, OPC-10, OPC-11, OPC-12, OPC-13 and OPC-14 revealed similarity in band patterns between the isolates and the control. Clustering of banding patterns generated from amplification with primer OPC-12 using Pearson’s coefficient detected similarity at 99.10%, 97.60%, 86.30% and 99.40%, 99.10%, 87.60%, 78.50% among <em>Aspergillus niger</em> and <em>Aspergillus carbonarious</em> strains, respectively, confirming the identification of potential ochratoxigenic black <em>Aspergillus</em> strains in the GP. The findings from this study suggest that GP obtained from some grape cultivars could be unsafe as food ingredients due to contamination by ochratoxigenic-producing molds, which is an indicative factor for the presence of ochratoxin A and other mycotoxins.

Occurrence of Ochratoxin A–Producing Fungi in Raw Brazilian Coffee

2001 ◽  
Vol 64 (8) ◽  
pp. 1226-1230 ◽  
Author(s):  
G. R. URBANO ◽  
M. H. TANIWAKI ◽  
M. F. de F. LEITÃO ◽  
M. C. VICENTINI
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Aspergillus Ochraceus ◽  
Direct Plating ◽  
Production Region ◽  
Agar Plug ◽  
Coffee Beans ◽  
High Level ◽  
And Storage ◽  
Positive Results

Ochratoxin A (OA)–producing fungi were identified in coffee at different stages of maturation. The toxin was quantified in coffee during terrace drying and in coffee stored in barns. By direct plating, a high level of contamination (100%) was found in the coffee beans studied, with the genus Aspergillus representing 33.2%, of which Aspergillus ochraceus and Aspergillus niger represented 10.3 and 22.9%, respectively, of the strains isolated from the coffee beans. The capacity to produce ochratoxin was determined in 155 strains of A. ochraceus and A. niger using both the agar plug method and extraction with chloroform, giving positive results for 88.1% of the A. ochraceus strains and 11.5% of the A. niger strains. Analysis for OA in the terrace and barn coffee samples showed that, independent of cultivar, year harvested, or production region, all except one of the samples analyzed showed mycotoxin levels below the limit suggested by the European Common Market (8 μg/kg), thus indicating that the problem is restricted and due to severe faults in harvesting and storage practices.

Effect of water activity on ochratoxin A production by Aspergillus niger aggregate species

2006 ◽  
Vol 108 (2) ◽  
pp. 188-195 ◽  
Author(s):  
A. Esteban ◽  
M.L. Abarca ◽  
M.R. Bragulat ◽  
F.J. Cabañes
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Water Activity ◽  
Effect Of Water

Influence of light on growth, conidiation and the mutual regulation of fumonisin B2 and ochratoxin A biosynthesis by Aspergillus niger

2012 ◽  
Vol 5 (2) ◽  
pp. 169-176 ◽  
Author(s):  
F. Fanelli ◽  
M. Schmidt-Heydt ◽  
M. Haidukowski ◽  
R. Geisen ◽  
A. Logrieco ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Blue Light ◽  
Short Wave ◽  
Light Conditions ◽  
Dark Incubation ◽  
Mutual Regulation ◽  
Blue Wavelength ◽  
Fumonisin B2 ◽  
Dark Production

Aspergillus niger is a fungus able to produce the carcinogenic mycotoxins ochratoxin A (OTA) and fumonisins. We analysed the influence of light of various wavelengths on growth, conidiation, fumonisin B2 (FB2) and OTA biosynthesis by A. niger ITEM 7097. Light from both sides of the spectrum, from long (627 nm) to short wavelengths (470-455 nm), had a stimulating effect on growth, with the highest stimulation under blue (455 nm, 1,700 Lux) and short-wave blue light (390 nm). Conidiation was reduced by 40% under a short blue wavelength (455 nm, 200 Lux), but strongly promoted under light at an even shorter wavelength (390 nm), with an increase of about 200 fold in comparison to the dark. Production of FB2 and OTA was mutually regulated by light. FB2 production was promoted under light conditions: red and blue light in particular increased FB2 biosynthesis by 40%. Conversely, OTA production was greatly inhibited under red and blue light in comparison to dark incubation, with a mean reduction of about 40 fold, indicating a reverse regulation of both biosynthetic pathways. Incubation under a 390 nm wavelength repressed the production of both toxins to non-detectable levels.

scholarly journals Comparison of working memory and sensory profile in boys and girls with writing disability

2019 ◽  
Vol 21 (4) ◽  
pp. 163-168
Author(s):  
Alireza Sangani ◽  
Paria Jangi
Keyword(s):  
Working Memory ◽  
Auditory Processing ◽  
Physical State ◽  
Multisensory Processing ◽  
The Body ◽  
Body Motion ◽  
Sensory Profile ◽  
Statistical Population ◽  
Significant Difference ◽  
And Storage

Background and aims: The main problems of children with learning disabilities are in cognition and their sensations. This study aimed to investigate the comparison of working memory and sensory profile in boys and girls with writing disability. Methods: The methodology of this descriptive study was the comparative type. The statistical population of this study was all girls and boys by the age of 8-10 suffering from the writing disability in Gorgan City during treatment in a writing disability center in summer of 2018. According to the research method, the stratified random sampling method was used and 50 boys and 58 girls were selected from each group. According to research tools, the Dunn profile (1999) was obtained from the parents of the children. In the area of Daneman, & Carpenter working memory (1980), questions were asked from the children directly, and the information related to processing and storage in their memory were received. Data were analyzed using multivariate analysis of variance analysis using SPSS24 software. Results: Descriptive findings showed that mean and standard deviation in boys and girls were respectively in Processing (50.32±6.93, 54.22±7.45), Storage (48.47±6.08, 53.17±6.07), Indoctrination associated with the physical state of the body motion (34.28±7.09, 36.91±6.48), Multisensory processing (34.68±5.21, 37.94±6.57), Auditory Processing (31.74±5.84, 35.52±6.59). Also the results indicate that there is a significant difference in the writing disability among processing (P<0.006) and storage (P<0.000) of working memory subscales and the Indoctrination associated with the physical state of the body motion (P<0.000), Multisensory processing (P<0.000) and Auditory Processing (P<0.002), of the sensory profile variable in both the girls and boys with writing disability. Conclusion: with regard to the results obtained, it can be concluded that the boys group is in worse conditions in working memory and sensory processing styles, which requires a special attention and more focused educational approaches.

scholarly journals DETECTION AND INVESTIGATION OF ASPERGILLUS NIGER AND OCHRATOXIN A IN WALNUT AND PEANUT

2017 ◽  
Vol 48 (5) ◽  
Author(s):  
Khalifa & et al.
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Plant Protection ◽  
Uv Light ◽  
Wave Length ◽  
Artificial Medium ◽  
College Of Agriculture ◽  
Local Markets ◽  
Layer Chromatography ◽  
Isolation Test

This study was conducted at the Department of Plant Protection-College of Agriculture-University of Baghdad during 2015 -2016. The objective of the study is to investigate the contamination of the fungus Aspergillus niger in the seeds of peanuts and walnuts from the Iraqi local markets and the ability of these isolates to produce ochratoxin A in artificial medium. Forty samples of peanuts and walnuts were collected from local markets of the governorates of Baghdad, Erbil, Sulaymaniyah , Anbar and Dyiala for isolation test of  A. nigar. Results showed that A.niger was founded in the samples of walnuts from Erbil at percentage of 50% and 42.8% in the samples of peanuts from Baghdad ,and 40 % in peanuts from each Anbar and Dyiala, in addition to the fungus A.flavus at a rate of33.3 و 28.8 %  in the walnuts from Erbil and Baghdad respectively and 30% و28.8% in the peanuts from Anbar and Baghdad respectively. Eleven isolates of fungus A.niger was tested against its ability to produce Ochratoxin A after grown in yeast and sucrose extract media and analyzed using thin layer chromatography (TLC) under UV light wave length of 365 nanometer, two isolates were identified (K,E) out of the A.niger fungus isolated from peanuts found to be able to produce Ochratoxin A at different rates, depending on the degree of the brightness of the spots compared with standard Toxin. Then the eleven isolates were identified by morphology characters and confirm by using specific primer NIG1and NIG2, all the isolates showed to be A.niger.

scholarly journals Ochratoxin A Producing Fungi, Biosynthetic Pathway and Regulatory Mechanisms

Toxins ◽  
2016 ◽  
Vol 8 (3) ◽  
pp. 83 ◽  
Author(s):  
Yan Wang ◽  
Liuqing Wang ◽  
Fei Liu ◽  
Qi Wang ◽  
Jonathan Selvaraj ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Biosynthetic Pathway ◽  
Regulatory Mechanisms

Effect of cultivation and storage pH on the production of multiple forms of polygalacturonase by Aspergillus niger

1996 ◽  
Vol 18 (1) ◽  
pp. 41-44 ◽  
Author(s):  
E. Stratilov� ◽  
E. Breierov� ◽  
R. Vadkertiov�
Keyword(s):  
Aspergillus Niger ◽  
Multiple Forms ◽  
And Storage

scholarly journals Aflatoxigenic and ochratoxigenic moulds and their toxins in tree nuts on Serbian market

2020 ◽  
pp. 9-18
Author(s):  
Irena Rakic ◽  
Gordana Dimic ◽  
Marija Skrinjar ◽  
Suncica Kocic-Tanackov
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
Immunosorbent Assay ◽  
Alternaria Alternata ◽  
Rhizopus Oryzae ◽  
Limit Of Detection ◽  
Average Concentration ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mean Values ◽  
Tree Nuts

In this study, moulds and mycotoxins presence in different tree nuts were investigated. The results showed that all of the 25 samples were contaminated with moulds. Mean values of total mould count varied from 1-4.9 cfu per grain. The most frequent species in hazelnut samples were Rhizopus oryzae (32.2%) and Aspergillus niger (28.9%). In walnuts A. niger (75.6%), in cashews also A. niger (42.4%) while in pistachio samples Alternaria alternata (20.7%), and Cladosporium cladosporioides (20.7%) were the most dominant. Rhizopus oligosporus was the only identified species in all almond samples (100%). Using Enzyme Linked Immunosorbent Assay (ELISA), the presence of total aflatoxins and ochratoxin A was examinated. In all analyzed samples, levels of ochratoxin A were below the limit of detection. Total aflatoxins were detected only in walnut samples with average concentration of 7.1 ?g/kg.

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