In vitro effect of some fungicides used in cultivation of Capsicum spp. on growth and ochratoxin A production by Aspergillus species

2013 ◽  
Vol 6 (2) ◽  
pp. 159-165
Author(s):  
L. Santos ◽  
S. Marín ◽  
V. Sanchis ◽  
A.J. Ramos
Keyword(s):  
Ochratoxin A ◽  
High Performance ◽  
Fruit Production ◽  
Aspergillus Species ◽  
Aspergillus Ochraceus ◽  
Fungal Load ◽  
Capsicum Spp ◽  
Vitro Effect ◽  
Yeast Extract Sucrose

The present study aimed to assess the effect of some pre-harvest fungicides commonly used in Capsicum fruit production on growth and ochratoxin A production of three Aspergillus species found in Capsicum powder. Aspergillus tubingensis, Aspergillus ochraceus and Aspergillus westerdijkiae, previously isolated from paprika and chilli, were inoculated on yeast extract sucrose agar and paprika extract agar supplemented with different fungicides at their recommended dosage rates, and incubated at 20 and 30 °C during 7 days. Radial growth was measured after 3, 5 and 7 days and ochratoxin A production was determined by high-performance liquid chromatography with fluorescence detection on day 7. Dodine 40% and mancozeb 80% were the most effective fungicides in inhibiting growth and ochratoxin A production, regardless of the fungal strain tested or temperature conditions. Whereas the application of fungicides could be very attractive in reducing the mycotoxigenic fungal load, it can also stimulate ochratoxin A production in some cases.

scholarly journals Ochratoxin Production by the Aspergillus ochraceus Group and Aspergillus alliaceus

2002 ◽  
Vol 68 (5) ◽  
pp. 2326-2329 ◽  
Author(s):  
Paul Bayman ◽  
James L. Baker ◽  
Mark A. Doster ◽  
Themis J. Michailides ◽  
Noreen E. Mahoney
Keyword(s):  
Ochratoxin A ◽  
Fungal Infections ◽  
Common Species ◽  
Aspergillus Ochraceus ◽  
Potato Dextrose Broth ◽  
Tree Nuts ◽  
Aspergillus Alliaceus ◽  
Fungal Secondary Metabolite ◽  
Yeast Extract Sucrose

ABSTRACT Ochratoxin A is a toxic and carcinogenic fungal secondary metabolite; its presence in foods is increasingly regulated. Various fungi are known to produce ochratoxins, but it is not known which species produce ochratoxins consistently and which species cause ochratoxin contamination of various crops. We isolated fungi in the Aspergillus ochraceus group (section Circumdati) and Aspergillus alliaceus from tree nut orchards, nuts, and figs in California. A total of 72 isolates were grown in potato dextrose broth and yeast extract-sucrose broth for 10 days at 30°C and tested for production of ochratoxin A in vitro by high-pressure liquid chromatography. Among isolates from California figs, tree nuts, and orchards, A. ochraceus and Aspergillus melleus were the most common species. No field isolates of A. ochraceus or A. melleus produced ochratoxin A above the level of detection (0.01 μg/ml). All A. alliaceus isolates produced ochratoxin A, up to 30 μg/ml. We examined 50,000 figs for fungal infections and measured ochratoxin content in figs with visible fungal colonies. Pooled figs infected with A. alliaceus contained ochratoxin A, figs infected with the A. ochraceus group had little or none, and figs infected with Penicillium had none. These results suggest that the little-known species A. alliaceus is an important ochratoxin-producing fungus in California and that it may be responsible for the ochratoxin contamination occasionally observed in figs.

In vitro effect of ochratoxin A and deoxynivalenol on the expression of interleukin 5 and interferon-gamma in broiler chicken lymphocytes

2016 ◽  
Vol 9 (2) ◽  
pp. 299-304 ◽  
Author(s):  
C. Lautert ◽  
L. Ferreiro ◽  
M.I. Azevedo ◽  
S.A. Botton ◽  
J.T. Santos ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Interferon Gamma ◽  
Broiler Chickens ◽  
Broiler Chicken ◽  
Fungal Metabolites ◽  
Interleukin 5 ◽  
T Helper 2 ◽  
Ifn Γ ◽  
Vitro Effect

Cytokines are proteins secreted by cells of innate and acquired immunity, produced in response to various antigens and responsible for mediating several function of these cells. Our study evaluated the profile of cytokines interleukin 5 (IL-5) and interferon gamma (IFN-γ), induced in lymphocytes of broiler chickens in response to secondary fungal metabolites ochratoxin A (OTA) and deoxynivalenol (DON) at concentrations of 0.001, 0.01, 0.1 and 1 μg/ml. The quantification of the cytokines was analysed at 24, 48 and 72 h after incubation with mycotoxins, using real-time PCR (qRT-PCR). The results obtained showed that OTA induced mRNA synthesis of IL-5 at concentrations 0.001, 0.1 and 1 μg/ml after 24 h of lymphocyte incubation, while at 48 h only the expression of the IL-5 cytokine at a concentration of 1 μg/ml (P<0.05) was detected. DON in a concentration of 1 μg/ml induced the expression of IL-5 in the lymphocytes only at 48 h post-incubation period (P<0.05). Regarding IFN-γ, gene expression was not observed in the lymphocytes of broiler chickens incubated with OTA and DON. The data obtained represent a profile of response mediated by T helper 2 cells to the exposure of broiler chicken immune cells to different concentrations of OTA and DON.

In Vitro Removal of Ochratoxin A by Wine Lactic Acid Bacteria

2007 ◽  
Vol 70 (9) ◽  
pp. 2155-2160 ◽  
Author(s):  
VINCENZO DEL PRETE ◽  
HECTOR RODRIGUEZ ◽  
ALFONSO V. CARRASCOSA ◽  
BLANCA de las RIVAS ◽  
EMILIA GARCIA-MORUNO ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Ochratoxin A ◽  
High Performance ◽  
Culture Medium ◽  
Degradation Products ◽  
Cell Binding ◽  
A Cell ◽  
In Vitro Interaction

A study was carried out to determine the in vitro interaction between ochratoxin A (OTA) and wine lactic acid bacteria (LAB). Fifteen strains belonging to five relevant oenological LAB species were grown in liquid synthetic culture medium containing OTA. The portion of OTA removed during the bacterial growth was 8 to 28%. The OTA removed from the supernatants was partially recovered (31 to 57%) from the bacterial pellet. Cell-free extracts of three representative strains were produced by disrupting cells in a French pressure cell. The ability of crude cell-free extracts to degrade OTA was studied. OTA was not degraded by cell-free extracts of wine LAB strains, and no degradation products of OTA were detected in the high-performance liquid chromatograms of the methanol extract of the bacterial pellet. On the basis of these results, we conclude that OTA removal by wine LAB is a cell-binding phenomenon. The chemistry and the molecular basis of OTA binding to wine LAB remains unknown.

scholarly journals Ochratoxigenic fungi and Ochratoxin A determination in dried grapes marketed in Tunisia

2020 ◽  
Vol 70 (1) ◽  
Author(s):  
Samir Chebil ◽  
Wafa Rjiba-Bahri ◽  
Souheib Oueslati ◽  
Hanen Ben Ismail ◽  
Anis Ben-Amar ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Ochratoxin A ◽  
High Performance ◽  
Its Region ◽  
Production Test ◽  
Potential Health ◽  
Dried Grapes ◽  
Pcr Product ◽  
Polymerase Chain

Abstract Purpose With the present work, we aimed to assess the occurrence of ochratoxigenic fungi and Ochratoxin A (OTA) in dried grapes from Tunisia. Methods Dried grapes samples (n = 90) were investigated for the presence of ochratoxigenic fungi, which were further characterized at the species level through amplification of the internal transcribed spacer (ITS) region and polymerase chain reaction (PCR) product sequencing. Fungal isolates were tested for their ochratoxigenic potential by high-performance liquid chromatography with fluorescence detection (HPLC-FLD), as well as dried grapes samples after an immunoaffinity column (IAC) clean-up procedure. Results Black Aspergilli isolates were the dominant genre among the filamentous fungi found in dried grapes samples and were the only OTA-producing fungi encountered. Aspergillus niger aggregate were the most frequently found isolates reaching 70%, 80%, and 85% in dried grapes samples from regions of Kelibia, Sfax, and Rafraf, respectively, while covered 100% of the relevant mycobiota found in imported samples. Aspergillus carbonarius isolates were found only in Sfax’s and Kelibia’s samples, while uniseriate Aspergilli were found between 7 and 20% in dried grapes from Kelibia, Sfax, and the imported samples. The in vitro OTA production test showed that 88.9% of OTA-producing isolates belonged to A. carbonarius with OTA levels varying from 0.06 to 1.32 μg/g of Czapek Yeast Agar (CYA). The remaining OTA-producing fungi (11.1 %) belonged to A. niger aggregate group having a maximum OTA potential of 2.88 μg/g CYA, and no uniseriate Aspergilli isolate was able to produce OTA. All dried grapes samples were free of OTA presence. Conclusion According to the present study’s findings, no OTA contamination was recorded in the investigated samples from Tunisian market. Nevertheless, the presence of strong OTA producers A. carbonarius in samples originated from the two out of three studied Tunisian regions, as well the high incidences of Aspergillus niger aggregate group with an attested potential for OTA production in all samples, necessitates further research on Tunisian dried grapes. Additionally, a continuous analysis of staple food of the Mediterranean diet is imperative to insure the best quality for the consumers and prevent potential health problems.

Ochratoxins A and B, Xanthomegnin, Viomellein and Vioxanthin Production by Isolates of Aspergillus ochraceus from Green Coffee Beans

1983 ◽  
Vol 46 (11) ◽  
pp. 965-968 ◽  
Author(s):  
MICHAEL E. STACK ◽  
PHILIP B. MISLIVEC ◽  
TURGUT DENIZEL ◽  
REGINA GIBSON ◽  
ALBERT E. POHLAND
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Ochratoxin A ◽  
High Performance ◽  
Toxin Production ◽  
Aspergillus Ochraceus ◽  
Average Level ◽  
Green Coffee ◽  
Green Coffee Beans ◽  
Coffee Beans

Isolates from Aspergillus ochraceus obtained from green coffee beans were cultured on rice and water. After 20 d of growth the cultures were extracted with chloroform and the extracts were analyzed by high performance liquid chromatography for ochratoxin A (OA), ochratoxin B (OB), xanthomegnin (X), viomellein (V) and vioxanthin (VX). Forty-three percent of the isolates produced OA at an average level of 397 μg of toxin/g rice, 17% produced OB at an average level of 312 μg/g, and 84% produced X, V, and VX at an average level of 281, 417 and 386 μg/g, respectively. The highest levels of toxin production were OA, 2088 μg/g; OB, 3375 μg/g; X, 1562 μg/g; V, 2514 μg/g; and VX, 2054 μg/g. VX has not previously been reported as an A. ochraceus metabolite.

scholarly journals Effect of a Debaryomyces hansenii and Lactobacillus buchneri Starter Culture on Aspergillus westerdijkiae Ochratoxin A Production and Growth during the Manufacture of Short Seasoned Dry-Cured Ham

2020 ◽  
Vol 8 (10) ◽  
pp. 1623
Author(s):  
Lucilla Iacumin ◽  
Martina Arnoldi ◽  
Giuseppe Comi
Keyword(s):  
Ochratoxin A ◽  
Starter Culture ◽  
Debaryomyces Hansenii ◽  
Aspergillus Ochraceus ◽  
In Situ Tests ◽  
Potential Health ◽  
Lactobacillus Buchneri ◽  
Dry Cured Ham ◽  
Aspergillus Westerdijkiae

Recently, specific dry-cured hams have started to be produced in San Daniele and Parma areas. The ingredients are similar to protected denomination of origin (PDO) produced in San Daniele or Parma areas, and include pork leg, coming from pigs bred in the Italian peninsula, salt and spices. However, these specific new products cannot be marked as a PDO, either San Daniele or Parma dry cured ham, because they are seasoned for 6 months, and the mark PDO is given only to products seasoned over 13 months. Consequently, these products are called short-seasoned dry-cured ham (SSDCH) and are not branded PDO. During their seasoning period, particularly from the first drying until the end of the seasoning period, many molds, including Eurotium spp. and Penicillium spp., can grow on the surface and work together with other molds and tissue enzymes to produce a unique aroma. Both of these strains typically predominate over other molds. However, molds producing ochratoxins, such as Aspergillus ochraceus and Penicillium nordicum, can simultaneously grow and produce ochratoxin A (OTA). Consequently, these dry-cured hams may represent a potential health risk for consumers. Recently, Aspergillus westerdijkiae has been isolated from SSDCHs, which could represent a potential problem for consumers. Therefore, the aim of this study was to inhibit A. westerdijkiae using Debaryomyces hansenii or Lactobacillus buchneri or a mix of both microorganisms. Six D. hansenii and six L. buchneri strains were tested in vitro for their ability to inhibit A. westerdijkiae. The strains D. hansenii (DIAL)1 and L. buchneri (Lb)4 demonstrated the highest inhibitory activity and were selected for in situ tests. The strains were inoculated or co-inoculated on fresh pork legs for SSDCH production with OTA-producing A. westerdijkiae prior to the first drying and seasoning. At the end of seasoning (six months), OTA was not detected in the SSDCH treated with both microorganisms and their combination. Because both strains did not adversely affect the SSDCH odor or flavor, the combination of these strains are proposed for use as starters to inhibit OTA-producing A. westerdijkiae.

Antimicrobial and Antiochratoxic Activities of Mentha spicata Essential Oil

2021 ◽  
Author(s):  
M. Brahmi ◽  
D.E.H. Adli ◽  
M.Y. Boufadi ◽  
W. Arabi ◽  
K. Kahloula ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Essential Oil ◽  
High Performance ◽  
Pathogenic Bacteria ◽  
Production Capacity ◽  
Aspergillus Ochraceus ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Mentha Spicata

The principle aim of this work is to evaluate the antimicrobial and antiochratoxic power of the essential oil of Mentha spicata (EOM). This oil was obtained by hydrodistillation with a yield of 0.3%. EOM was screened for its possible antibacterial activity in vitro against five strains of pathogenic bacteria, using the solid disc diffusion method and the microdilution method. The extract reacted positively to the bacterial strains tested. The results of the antifungal activity show an inhibition of mycelial growth; it is total on Aspergillus ochraceus, Aspergillus flavus, Aspergillus niger, Penicillium viridicatum, and on Rhizopus stolonifer and Alternaria alternate at a concentration of 12.5 μl/ml. Tests carried out on yeasts mainly referenced as Candida albicans IP444 and Candida albicans 2679 showed minimal inhibition (MIC) of the order of 7.81 μl/ml and 0.97 μl/ml, respectively and theMICis of the order of 0.48 μl/ml for Candida albicans 10 231. In addition, the EOM antiochratoxigenic test for ochratoxin A production capacity following a series of high performance liquid chromatography separation and ultraviolet detection (HPLC–UV) analyses detected an inhibitory effect proportional to the EOM concentration. In general, the essential oil showed an effective antimicrobial action on the growth of the tested pathogens and an antiochratoxigenic.

scholarly journals Carbon Catabolite Repression Gene AoCreA Regulates Morphological Development and Ochratoxin A Biosynthesis Responding to Carbon Sources in Aspergillus ochraceus

Toxins ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 697
Author(s):  
Gang Wang ◽  
Yulong Wang ◽  
Bolei Yang ◽  
Chenxi Zhang ◽  
Haiyong Zhang ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Catabolite Repression ◽  
Carbon Catabolite Repression ◽  
Carbon Sources ◽  
Aspergillus Ochraceus ◽  
Morphological Development ◽  
Drastic Reduction ◽  
Food And Feed ◽  
Yeast Extract Sucrose ◽  
Insight Into

Carbon is one of the most important nutrients for the development and secondary metabolism in fungi. CreA is the major transcriptional factor mediating carbon catabolite repression, which is employed in the utilization of carbon sources. Aspergillus ochraceus contaminates various food and feed containing different carbon sources by producing ochratoxin A (OTA). However, little is known about the function of AoCreA in regulating the morphology and OTA production of A. ochraceus. To give an insight into the mechanism of the carbon sources regulating development of A. ochraceus and OTA production, we have identified AoCreA in A. ochraceus. The homologous recombination strategy was used to generate the AoCreA deletion mutant (ΔAoCreA). We have investigated the morphology and OTA production of the wild type (WT) and ΔAoCreA of A. ochraceus with media containing different carbon sources (glucose, fructose, maltose, D-xylose, D-mannose, acetate, D-galactose, D-mannitol and lactose). ΔAoCreA showed a significant growth and conidiation defect on all media as compared with WT. Glucose and maltose were the most inducing media for OTA production by A. ochraceus, followed by sucrose and the nutrient-rich Yeast Extract Sucrose (YES) and Potato Dextrose Agar (PDA). The deletion of AoCreA led to a drastic reduction of OTA production on all kinds of media except PDA, which was supported by the expression profile of OTA biosynthetic genes. Furthermore, infection studies of ΔAoCreA on oats and pears showed the involvement of AoCreA in the pathogenicity of A. ochraceus. Thus, these results suggest that AoCreA regulates morphological development and OTA biosynthesis in response to carbon sources in A. ochraceus.

scholarly journals In vitro effect of marigold seed exudates on plant parasitic nematodes

2005 ◽  
Vol 86 (1) ◽  
pp. 31-35 ◽  
Author(s):  
Ekaterini Riga ◽  
Catharine Hooper ◽  
John Potter
Keyword(s):  
High Performance ◽  
Heterodera Schachtii ◽  
Parasitic Nematodes ◽  
Tagetes Erecta ◽  
Meloidogyne Hapla ◽  
Pratylenchus Penetrans ◽  
Plant Parasitic Nematodes ◽  
Water Control ◽  
Vitro Effect

Water extracts from seed exudates ofTagetes erectacv. Crackerjack andT. patulavar.polynemacaused significantly higher mortality (P <0.05) toHeterodera schachtii, Meloidogyne haplaandPratylenchus penetransthan the control extracts from radish, tomato and corn seeds, respectively. Marigold seed exudates consist of nematicidal compounds. Nematostatic compounds have not been found in the seed exudates. Two high-performance liquid chromatography fractions derived fromT. erectacv. Crackerjack and one fromT. patulavar.polynemacaused the highest mortality ofH. schachtiiin comparison with a water control and the rest of the fractions.

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