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.

Quantitation of Ochratoxin A: Use of Reverse Phase Thin-Layer Chromatography for Sample Cleanup Followed by Liquid Chromatography or Direct Fluorescence Measurement

1988 ◽  
Vol 71 (5) ◽  
pp. 949-953 ◽  
Author(s):  
Andrzej A Frohlich ◽  
Ronald R Marquardt ◽  
Aniko Bernatsky
Keyword(s):  
Liquid Chromatography ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Ochratoxin A ◽  
Uv Light ◽  
Packed Column ◽  
Fluorescence Measurement ◽  
Reverse Phase ◽  
Direct Fluorescence ◽  
Layer Chromatography

Abstract An improved procedure for sample preparation and quantitation of ochratoxin A in moldy grain was developed. Grain samples were acidified and extracted, and extracts were subjected to reverse phase thin-layer chromatography (RPTLC). The separated spots, which were identified under UV light, were scraped and collected into recovery devices. Ochratoxin A was eluted from the adsorbent and analyzed by either liquid chromatography with fluorescence detection or direct spectrofluorometric measurement. The method yielded values that were proportional to the concentrations of toxin in the sample, had relatively high levels of recovery (94%), and required considerably less volume of solvents and preparation time than a standard packed column method.

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 Microbial Contamination in Some Commercial Biscuits in Baghdad City

2010 ◽  
Vol 7 (2) ◽  
pp. 867-875
Author(s):  
Baghdad Science Journal
Keyword(s):  
Staphylococcus Aureus ◽  
Aspergillus Niger ◽  
Bacillus Cereus ◽  
Microbial Contamination ◽  
Local Markets ◽  
Esherichia Coli ◽  
Bacteria And Fungi ◽  
Penicillium Spp ◽  
Number Of Bacteria

This study has been conducted to know the level of microbial ( bacteria and fungi) contamination in 5 types of biscuits from local markets of Baghdad city. Fifty samples (ten sample for each kind of biscuit) were studed,Two are local,others are Iranian,Turkish,and Holandies. The following results have been achieved :1. The highest number of bacteria was 21.6×103 cell/g in Iranian biscuit while the lowest number was 14.3× 103 cell/g in local biscuit No.1 . The highest number of fungi was 16×103 colony/g and the lowest number was 5.3×103 colony/g in the Iranian and the local biscuit No.1,respectively.2. Staphylococcus aureus was the major bacteria appeared at highest level of 100% in Turkish biscuit. The lowest percentage was found in Hollandian biscuit with 37.28%. Bacillus cereus was the major bacteria with a percentage of 100% in local biscuit No.2 where as the lowest was in local biscuit No,1with a percentage of 20.93%, while it was not existed in Turkish biscuit. Esherichia coli was found in Hollandian biscuit at highest rate of 38.98% , the lowest value was appeared in Iranian biscuit with 28.16% while it was not exited in local biscuit No.1,2 and Turkish biscuit.3. Aspergillus niger appeared at highest level of 66.66% in Hollandian biscuit, while was the lowest 37.73% in local biscuit No.1 and not existed in local biscuit No.2, The highest value of A.flavus was 69.76% in local biscuit No.2 and the lowest value in Hollandian biscuit in percentage 8.33%. It has not appeared in Iranian and Turkish biscuit. The A. terreus appeared at highest rate in Turkish biscuit with 33.33% , the lowest value was in local biscuit No.2 at 11.62% and was not appeared in Hollandian biscuit.The Penicillium spp. Was found at highest rate 25% in Hollandian biscuit , the lowest value of 9.52% was appeared in Turkish biscuit.

scholarly journals Identification of phenolic compounds of dry extract of dandelion herb and large burdock leaf tea

2019 ◽  
Vol 18 (2) ◽  
pp. 73-77
Author(s):  
L. M. Fedoseeva ◽  
Yu. I. Chistova
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Phenolic Compounds ◽  
High Performance ◽  
Uv Light ◽  
Spectral Characteristics ◽  
Water System ◽  
Dry Extract ◽  
Caffeic Acid Derivatives ◽  
Layer Chromatography

The purpose of this work is to study of phenolic compounds in the dry extract of dandelion herb and large burdock leaf tea.Materials and methods . The separation and identification of phenolic compounds of dry extract of dandelion herb and large burdock leaf tea by thin-layer chromatography and high-performance liquid chromatography with UV-detectionhas been carried out.Results . As a result of research, it has been established that during TLC the optimal system for the separation of phenolic compounds is the ethyl acetate – formic acid – water system (10:2:3). On the chromatogram four spots were found corresponding to the value of Rf and fluorescence in UV-light to flavonoids of the flavone group and phenolic acids (chlorogenic and caffeic acids). For further identification of phenolic compounds using HPLC, eight peaks were found, which in terms of retention time and spectral characteristics correspond to phenologlycosides, chlorogenic acid, caffeic acid derivatives, ferulic acid, umbelliferone.Conclusions . Thus, the dry extract of dandelion herb and large burdock leaf tea contains hydroxycinnamic acids and their derivatives, compounds of coumarin nature, phenologlycosides.

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.

Screening Method for the Detection of Aflatoxins, Ochratoxin, Patulin, Sterigmatocystin, and Zearalenone in Cereals

1977 ◽  
Vol 60 (6) ◽  
pp. 1369-1371 ◽  
Author(s):  
B G Egon Josefsson ◽  
Tord E Möller
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Ochratoxin A ◽  
Screening Method ◽  
Gel Filtration ◽  
Limits Of Detection ◽  
Layer Chromatography

Abstract A screening method has been developed for the detection of aflatoxins, ochratoxin A, patulin, sterigmatocystin, and zearalenone in cereals. After extraction, the sample is cleaned up by gel filtration. The mycotoxins are separated by thin layer chromatography. The limits of detection are about 5 μg aflatoxins, 10 ochratoxin A, 50 μg patulin, 10 μg sterigmatocystin, and 35 μg zearalenone/kg.

scholarly journals Rapid Identification and Quantitation of Clotrimazole, Miconazole, and Ketokonazole in Pharmaceutical Creams and Ointments by Thin-Layer Chromatography–Densitometry

1996 ◽  
Vol 79 (3) ◽  
pp. 656-660 ◽  
Author(s):  
Utpal Roychowdhury ◽  
Saroj K Das
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Uv Light ◽  
Internal Standard ◽  
Solvent System ◽  
Short Wave ◽  
Rapid Identification ◽  
Pharmaceutical Creams ◽  
Liquid Chromatographic ◽  
Layer Chromatography

Abstract Thin-layer chromatography (TLC)–densitometry was used to separate, identify, and quantitate clotrimazole, miconazole, and ketokonazole (alone or combined with other drugs) in various pharmacopoeial or proprietary creams and ointments. Clotrimazole was extracted from the cream or ointment with ethyl alcohol, and miconazole and ketokonazole were extracted with a mixture of equal volumes of chloroform and isopropyl alcohol. Active ingredients were separated from excipients and other drugs by TLC on a precoated silica gel F254 plate with a solvent system of n-hexane–chloroform–methanol–diethylamine (50 + 40 + 10 + 1, v/v). The 3 azoles were well separated and easily identified in this chromatographic system. The separated azoles were visualized under short-wave UV light and quantitated by scanning densitometry at 220 nm by comparing the integrated areas of samples with those of standard (one azole was used as internal standard for the other). Recoveries from samples spiked with known amounts of azoles were excellent. The method was validated further by comparison with official liquid chromatographic methods.

Screening and Quantitation of Ochratoxin A in Corn, Peanuts, Beans, Rice, and Cassava

1985 ◽  
Vol 68 (6) ◽  
pp. 1128-1130
Author(s):  
Lucia M Valente Soares ◽  
Delia R Rodriguez-Amaya
Keyword(s):  
Ochratoxin A ◽  
Chloroform Extract ◽  
Cupric Sulfate ◽  
Corn Meal ◽  
Black Beans ◽  
Polished Rice ◽  
Yellow Corn ◽  
Coefficients Of Variation ◽  
Layer Chromatography ◽  
Different Levels

Abstract To answer the need for simple, economical, rapid methods for mycotoxins, a procedure for screening and quantitation of ochratoxin A was developed. A methanol-aqueous KC1 extraction is used, followed by cleanup with clarifying agents and partition into chloroform. Part of the chloroform extract is used for screening and the other part for quantitation by thin layer chromatography (TLC). The screening procedure takes 40 min, using a silica gel/aluminum oxide minicolumn developed for this purpose. The limits of detection are 80 and 10 |xg/ kg, respectively, for minicolumn screening and TLC quantitation. Ammonium sulfate is efficient in cleaning samples of corn and cassava; cupric sulfate is better with peanuts, beans, and rice. Tests were conducted on triplicate spiked samples of yellow corn meal, raw peanuts, dried black beans, polished rice, and cassava flour at different levels (400, 200, 80, 40, and 10 p-g/kg). Recoveries ranged from 86 to 160% and the coefficients of variation ranged from 0 to 26%.

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