Effect of Aspergillus carbonarius amounts on winemaking and ochratoxin A contamination

Aspergillus carbonarius is the major ochratoxin A (OTA)-producing fungus that contaminates wine grapes. To investigate the effect of the initial amount of A. carbonarius on winemaking and ochratoxin A contamination, different conidial concentrations of A. carbonarius were manually added to the grape musts before fermentation. Sampling was carried out at different stages in alcoholic fermentation, including crushing, maceration, pressing and alcoholic fermentation. The levels of alcohols, soluble solids, and reducing sugars in the musts were analyzed before and during the whole procedure of alcoholic fermentation. Aspergillus spp. and other fungal contaminants increased rapidly after crushing, however most died at 48 h. OTA levels in the musts increased during the first 8–48 h and then decreased sharply in A. carbonarius inoculants (1 × 10⁴ to 1 × 10⁶ spores/g) in a spore concentration-dependent manner. Most OTA was retained in the pomaces fraction after the pressing operation. High amounts of A. carbonarius did not significantly affect yeast growth, sugar use, and alcoholic production during fermentation. In conclusion, high levels of contamination with A. carbonarius in the grape musts did not inhibit alcoholic fermentation, but caused high OTA residues in the wine produced.     

Ochratoxin A and ochratoxigenic black Aspergillus species in Tunisian grapes cultivated in different geographic areas

This paper summarizes the results of a large study on the occurrence of ochratoxigenic fungi and Ochratoxin A from wine and table grapes in Tunisia. Our results revealed that Aspergillus section Nigri were the unique potential OTA producing fungi isolated from grapes. Isolates belonging to Aspergillus niger aggregate were the most abundant species followed by Aspergillus carbonarius isolates, then uniseriate aspergilli. A. carbonarius presented the highest percentage of OTA-positive strains (97%) whereas only 3% of A. niger aggregate isolates were OTA positive. Grapes were analysed for their OTA content and 58% of them contained detectable levels of OTA, between 0.05 and 5.85 μg/l. Only 4 samples out of 39 exceeded the OTA limit of 2 μg/l fixed by the EU for wine and grape juices. The most contaminated grapes were those from Raf-Raf region located in the North-Est and characterized by a humid climate. Grapes from the Regueb region, characterized by an arid climate, were rarely contaminated. Furthermore, A. carbonarius, which is the main OTA producer fungi on grapes, was rarely isolated in Regueb.     

Determination,content analysis and removal efficiency of fining agents on ochratoxin A in Chinese wines

A simple and convenient HPLC-FD detection method for ochratoxin A (OTA) with a high detection limit and a short run time has been developed. OTA has been found in most samples of Chinese market wine, including domestic and imported wines, but the content was not very high. Only a few wines showed an OTA content that exceeded the EC and OIV limits, indicating that most Chinese market wines were safe. The OTA intake for Chinese from wine was 0.017 ng/kg (bw) per day, which was lower than the SCF and JECFA limits and also lower than in many other countries. This was mainly due to the low per capita wine consumption in China, but it is still necessary for the Chinese government and wine makers to monitor OTA levels in wine and to establish relevant regulations. An egg white treatment (0.20 mg/mL, 48 h) was the best removal method for OTA.     

First report: Penicillium adametzioides,a potential biocontrol agent for ochratoxin-producing fungus in grapes,resulting from natural product pre-harvest treatment

Ochratoxin A (OTA) is a secondary metabolite produced mainly by Aspergillus section Nigri (Aspergillus carbonarius is the most relevant strain in the Mediterranean region with a group 2B carcinogenic effect in humans. In vivo experiments were conducted in southern France involving applying pre-harvest Stifénia^® (elicitor), Scala^® (chemical fungicide) and two other control treatments [not contaminated by A. carbonarius (OTA-PF) and not treated and artificially contaminated by OTA-PF but not treated]. The Stifénia^® and Scala^® treatments significantly reduced the OTA juice contamination so that it was under the authorised uptake OTA limit. Stifénia^® highly affected the grape fungal ecosystem with new non-Aspergillus strains isolated from grape stems and juices. In vitro antagonistic tests were performed with Stifénia^® non-Aspergillus isolates (n = 10). Three antagonistic tests were applied using different distances (3 and 5 cm in between the two microorganisms) with two different inoculation times (at the same time and with three day intervals in between). Certain strains had a positive mycelial growth effect on A. carbonarius colonies, such as Penicillium spp. and Fusarium sp. Other strains displayed a reduction effect on OTA production of OTA-PF, such as Penicillium spp. (J2, J3). Penicillium adametzioides (S3) and Penicillium expansum (J1) (at certain stages) reduced the OTA production and mycelial growth. P. expansum was excluded as a bio-control agent because of its mycotoxin production ability. The higher challenge distance between certain strains of P. adametzioides (S3) and other Penicillium strains (as J1, J2, J3 and J4; at three and seven days) reduced the secretion of OTA by OTA-PF. This OTA production reduction could possibly prevent OTA contamination prevention in the case of epidemic favourable conditions by reducing the OTA produced in grape post-harvest products (i.e., juice). This could be accomplished by applying as the elicitor one of the tested fungi with an antagonistic effect on OTA production, such as P. adametzioides (at 10 days). Certain strains, such as P. adametzioides (S3) and J2 (P. spp.) should be further investigated to determine the details of the underlying mechanism of their OTA reduction and their ecosystem effects in cases of in vivo application.     

The incidence and distribution of ochratoxin A in Daqu,a Chinese traditional fermentation starter

Daqu, a traditional starter culture mainly used to produce Chinese liquor and vinegar, is spontaneously fermented by diverse bacteria, yeasts and filamentous fungi under thermophilic condition. Therefore, mycotoxins may exist in Daqu, resulting in the contamination of end-foods. Ochratoxin A (OTA), a mycotoxin produced by certain species of Aspergillus and Penicillium, is not known whether existing in Daqu. However, specific method to detect OTA as well as OTA occurrence in Daqu has not been reported so far. With this in mind, a new method was developed to detect OTA in Daqu by the combination of ultrasound-assisted solid-liquid extraction (USLE), solid phase extraction (SPE) cleanup and UPLC-MS/MS. The USLE conditions of OTA from Daqu were optimized using Plackett-Burman (PB) design coupled with Box-Behnken (BB) design. Under the optimized conditions, no matrix effects were found, and the external standard method can be used to determine OTA in Daqu. The recoveries for spiked samples were 87–106% with the relative standard deviations (RSD) < 15%. The limits of detection and quantification were respectively 0.33 and 0.41 ppb. This approach was then applied to analyze 133 Daqu samples from different geographical regions in China, including 26 low temperature-, 33 medium temperature- and 74 high temperature-type Daqu. The results showed that OTA was detected in 66 samples with a maximum concentration of 28.87 ppb in low temperature Daqu, and the OTA incidence was on increase in the order of high temperature-, medium temperature- and low temperature-type Daqu. This implied that fermentation temperature is the key factor influencing OTA occurrence in Daqu. Moreover, there may be some fungi possessing the biosynthesis ability of OTA under high temperature environment (more than 45 °C).     

Skin damage,high temperature and relative humidity as detrimental factors for Aspergillus carbonarius infection and ochratoxin A production in grapes

This study investigated the impact of skin damage on Aspergillus carbonarius colonization and ochratoxin A (OTA) production in grapes at different temperatures and relative humidity. Four ochratoxigenic A. carbonarius strains isolated from wine grapes were used to inoculate artificially damaged and undamaged table grapes. Grapes were stored at three levels of relative humidity (80%, 90% and 100%) and at two temperatures (20 and 30 °C). After seven days, the infection percentage of A. carbonarius was recorded and OTA accumulation in berries was analysed. Damaged grapes were more commonly infected and development of colonies was higher than in undamaged ones; consequently more OTA was detected in the former treatment. Temperature and relative humidity had significant influences on both infection and toxin content. The amount of OTA detected at 30 °C was higher than at 20 °C in most of the treatments. The highest relative humidity (100%) led to maximum amounts of OTA while no significant differences were found between 90% and 80% in the OTA content. The implementation of preventive measures in order to minimise berry damage in the field by controlling pathogenic fungi and insects during grape growing and removing visibly damaged grapes at harvest may significantly reduce OTA contamination in grapes.     

Verifying the red wines adulteration through isotopic and chromatographic investigations coupled with multivariate statistic interpretation of the data

The assessment of wine traceability and authenticity is a major concern that has gained a lot of interest internationally since the wine has always been subjected to various fraudulent practices. Practiced since ancient times, wine fraud has become more sophisticated in the present day, taking many forms. Consumers, regulatory bodies and manufacturers are all interested to have reliable analytical tools and information to allow the authentication and detection of wine adulteration or incorrect labelling. This research study evaluates and proposes a possible strategy for the detection of adulterated sweet or medium sweet red table wines using appropriate chemical parameters which can reveal prohibited practices in the winemaking process. The work is performed on 29 table wine samples, bought from the market, packed in PET bottles. Exogenous addition of sugar and water in the counterfeited table red wines was detected by the measurement of stable isotopes content (δ¹³C and δ¹⁸O) known as origin markers and supplementary confirmed by other classical parameters, as the alcoholic strength of the wines (‰ vol.) and the presence of 5-(hydroxymethyl)-2-furaldehyde (HMF) and of synthetic sweeteners or synthetic red dyes used to correct deficiencies of taste and colour. Additionally, the nature and profile of anthocyanins, as indicator of the red colour of wine, was investigated in the table wines and then compared with that of authentic wines obtained by microvinification of Vitis vinifera, in order to determine their authenticity.     

Biopreservation potential of lactic acid bacteria from Andean fermented food of vegetal origin

Microbial fermentations have long represented a way of natural biopreservation of raw materials, which frequently originated new food products. Among them, traditionally fermented products still manufactured by native populations all around the world are source of lactic acid bacteria (LAB) strains with high biotechnological potential. LAB are food grade microorganisms and therefore a good alternative to chemicals to be applied in food preservation. A total of 130 LAB isolates recovered from “chicha” and “tocosh”, traditional fermented Andean products of vegetal origin, were screened for antimicrobial activities against spoiler fungi Meyerozyma guilliermondii CECT 1021 (synonym Pichia guilliermondii), Penicillium roqueforti CECT 2905^NT, Aspergillus oryzae CECT 2094^NT and Aspergillus niger CECT 2807 as well as against foodborne pathogens Escherichia coli O157:H7 CECT 5947, Listeria innocua CECT 910^T and Salmonella enterica subsp. enterica serovar Typhi CECT 4138. LAB isolates represented nine species and four genera that exhibited a general inhibition of food pathogens and were also active against A. oryzae and M. guilliermondii while a poor inhibition of A. niger and P. roqueforti was produced. Antifungal activity of cell free supernatants (CFS) from seven selected strains grown in MRS was confirmed against toxigenic fungi Aspergillus parasiticus CECT 2681, Penicillium expansum CECT 2278 and Fusarium verticilloides CECT 2987 and also on the three foodborne bacteria included in the study. Phenyllactic and 3,5-Di-O-caffeoylquinic acids were identified as the predominant bioactive compounds in CFS by QuEChERS extraction with LC-MS-LIT detection approach. Four out of seven strains free of antibiotic resistances involving L. plantarum M5MA1 and M9MM1 from chicha and L. fermentum T3M3 and Lc. mesenteroides T1M3 from tocosh showed high potential to be used as biopreservatives in food applications.     

Identification of antifungal peptides produced by Lactobacillus plantarum IS10 grown in the MRS broth

The use of secondary metabolites of lactic acid bacteria for preservation of foods is increasingly gaining interest to the food industry to replace synthetic preservatives. In this study, the cell free supernatant containing peptides obtained from Lactobacillus plantarum IS10 was fractionated by size exclusion chromatography using sephadex G-25, and tested against Aspergillus flavus MD3, Penicillium roqueforti MD4 and Eurotium rubrum MD5. Among the fractions, fraction number 10 showed 60% antifungal activity at a concentration of 0.02 mg peptide/mL. Four novel peptides out of twenty peptides obtained from fraction 10 were identified and determined by de novo sequencing. Peptide FPSHTGMSVPPP with a net charge +1, hydrophobicity ratio 58% and molecular weight of 1253 was further studied. The selected peptide showed a good activity at a concentration of 5 mg/mL against selected fungi and poor activity at low concentrations. This work indicates that L. plantarum IS10 has the capability of producing peptides which are affective against spoilage fungi.     

Inhibition of Aspergillus carbonarius and fungal contamination in table grapes using Bacillus subtilis

Aspergillus carbonarius is a major producer of ochratoxin A in grapes, causing fungal decay and posing a significant threat to human health. Bacillus subtilis CCTCC M 207209 was used to inhibit the growth of A. carbonarius CCTCC AF 2011004, an ochratoxin A-producing strain previously isolated from grapes. The inhibition effect in vitro was tested in potato dextrose agar medium (PDA), while in vivo effects were examined in grape berries of three different grape cultivars: Thompson Seedless, Kyoho, and Red Earth. Inhibitory effects were evaluated according to colony size in PDA and rotten spots in grape berries when A. carbonarius and B. subtilis were inoculated simultaneously and cultivated at 0 °C, 25 °C, or 30 °C. B. subtilis liquid cultures with and without cells and volatile products were used in the analyses. Significant inhibition of A. carbonarius was observed in all samples treated with B. subtilis liquid cultures, especially those subjected to cell-free culture treatment. No inhibition was observed for A. carbonarius treated with the volatile products of B. subtilis. The inhibition was the most significant in Red Earth grapes, followed by the Kyoho then Thompson Seedless varieties, when the same fraction of B. subtilis culture was used. Significant inhibition was also observed for other fungal contaminants in grapes when B. subtilis liquid culture supernatant was used. This study reveals the potential of B. subtilis for inhibiting contamination of OTA-producing A. carbonarius and other fungi in table grapes.     

Organic wine safety: UPLC-FLD determination of Ochratoxin A in Southern Italy wines from organic farming and winemaking

A fast reversed-phase UPLC method was utilized for Ochratoxin A (OTA) determination in 55 different wine samples (red and white) produced in Southern Italy, during two vintages. All the samples came from vineyards in which the plants were subjected to organic farming and were produced according to an organic winemaking, following strict rules on processing aids. Analytical methods included the clean-up purification by using commercial immunoaffinity columns and an Acquity UPLC^® system equipped with a fluorescent detector; the sensitivity of the analytical method was 0.01 ng mL⁻¹. OTA was detected in all wine samples analyzed and the levels were always below the maximum tolerable EU limit (2 ng mL⁻¹); the red wine samples proved to be more contaminated than the white ones.The occurrence incidence of OTA in wines produced according organic farming and winemaking was comparable with that of commercial wines conventionally produced and wines obtained from organic farming only. The results of this study indicate a low risk of exposure to OTA by consumption of these wines.     

Simultaneous determination of mycotoxin in commercial coffee

Mycotoxins are secondary metabolites produced by filamentous fungi that usually contaminate food products. Coffee is a natural product susceptible to mycotoxin contamination. The present study evaluates the presence of nivalenol, deoxynivalenol, T-2 and HT-2 Toxin, diacetoxyscirpenol, aflatoxin B₁, aflatoxin B₂, aflatoxin G₁, aflatoxin G₂, fumonisin B₁, fumonisin B₂, ochratoxin A, zearalenone, enniatin A, enniatin A₁, enniatin B, enniatin B₁, and beauvericin in coffee samples, using liquid chromatography tandem mass spectrometry (LC-MS/MS). The results show that zearalenone was not present in any sample. In the positive samples the contents of fumonisins ranged from 58.62 to 537.45 μg/kg, emerging mycotoxins ranged from 0.10 to 3569.92 μg/kg, aflatoxins ranged from 0.25 to 13.12 μg/kg, and trichothecenes, excepting nivalenol, ranged from 5.70 to 325.68 μg/kg. Nivalenol presented the highest concentrations, from 0.40 to 25.86 mg/kg. Ochratoxin A ranged from 1.56 to 32.40 μg/kg, and five samples exceeded the maximum limit established by the European Commission.     

Inhibition of Fusarium culmorum by carboxylic acids released from lactic acid bacteria in a barley malt substrate

The effect of carboxylic acids, composed by both organic and phenolic acids, released in a barley malt substrate fermented by lactic acid bacteria was tested against Fusarium culmorum macroconidia and compared under different fermentation conditions. Phenolic acids released by Lactobacillus plantarum FST1.7 and Lactobacillus brevis R2Δ were quantified using a QuEChERS method coupled with a HPLC-UV/PDA system. Their concentration improved with increasing extract content of the barley malt-based substrate and reached maximal concentrations after 48 h of fermentation performed at optimum growth temperature. Generally, phenolic acids were produced at levels far below their minimal inhibitory concentration (MIC), and limited synergistic effects were observed when mixed with organic acids. The fungal growth suppression by the wort fermented by Lb. brevis R2Δ (95 ± 9 h total inhibition) could be fully explained by the presence of antifungal carboxylic acids, whereas only partially accounted for Lb. plantarum FST1.7 (198 ± 19 h). Organic acids were mainly responsible for the ability of LAB fermented wort to cause fungal inhibition, whereas phenolic acids took only a secondary role at the low concentrations released. Longer fermentation times favoured primarily organic acid release, whereas fermentation of higher malt extract substrates encouraged both organic and phenolic acids production. The understanding on how synergy works between antifungal compounds could help to identify strategies to further increase their concentration in wort, with potential to replace synthetic broths and for direct application in food application.     

In vivo stability of the complex ochratoxin A – Saccharomyces cerevisiae starter strains

In recent years, several studies have focused on the role of yeasts as adsorbing tools to remove ochratoxin A (OTA) in musts and wines; however, no data are available on the stability of OTA-yeast complex. The present study was designed to assess the ability of five genetically distinct Saccharomyces cerevisiae strains (W13, W28, W46, W47, and Y28), previously studied for their oenological traits and in vitro OTA removal ability, to stably bind the toxin in Uva di Troia grape must (a red variety from Southern Italy). In addition, the effect of temperature, sugar concentration, and addition of ammonium salts on OTA binding was investigated.The highest binding was observed for S. cerevisiae W46 and W28 (42.79–76.44 and 34.51–70.17%, respectively); the other strains (W13, W47 and Y28) removed OTA by 20.34–53.79%. The binding was reversible and the extent of process was strongly affected by the kind of strain. Although the strains W46 and W28 removed OTA efficiently, they did not irreversibly bind OTA (ca. 80–85% release). On the other hand, the complex “S. cerevisiae W13-OTA” exhibited the greatest stability (ca. 55% release).The results obtained may be relevant not only to improve wine safety by integrating the binding ability in the criteria of selection of wine starters, but also for a more general biotechnological purpose, because of the increasing interest in the bioremediation of musts and wines using yeasts.     

Determination of heavy metals in selected black sea fish species

Heavy metals can be accumulated by marine organisms thought a variety of pathways, including respiration, adsorption and ingestion. The levels of heavy metals are known to increase drastically in marine environment through mainly anthropogenic activities. Fish are good indicators for the long term monitoring of metal accumulation in the marine environment. The aim of this study was to determine the levels of Cd, As, Hg, Pb, Zn and Cu in edible part and gill of seven most consumed Bulgarian fish species collected from north-east coast of Black Sea. These fish species are sprat (Sprattus sprattus sulinus), Mediterranean horse mackerel (Trachurus mediterraneus ponticus), Black sea gobies (Neogobius melanostromus), shad (Alosa pontica), Atlantic bonito (Sarda sarda), bluefish (Pomatomus saltatrix) and grey mullet (Mugil cephalus). The fish samples were collected during 2010. The analytical determination of As, Cd, Pb, Zn and Cu were performed by using flame and graphite furnace atomic absorption spectrometry after microwave digestion procedure. The total mercury determination was determined using a direct mercury analyzer (DMA-80). The metal concentration of analyzed elements was highest in the gill for all fish species. The maximum metal concentration was measured for Cu (1.40 mg kg⁻¹ w.w), Zn (11 mg kg⁻¹ w.w) and Pb (0.08 mg kg⁻¹ w.w) in muscle tissues of shad and sprat. The edible part of horse mackerel has the maximum value for Hg (0.12 mg kg⁻¹ w.w) while Atlantic bonito predominantly accumulates As (1.10 mg kg⁻¹ w.w). The analytical results obtained from this study were compared within acceptable limits for human consumption set by various health institutions.     

Aflatoxin contamination in unrecorded beers from Kenya – A health risk beyond ethanol

Samples of unrecorded opaque beers (n = 58; 40 based on maize, 5 on sorghum and 13 on other plants) and recorded wines (n = 8) in Kenya were screened for aflatoxins using a rapid ELISA technique followed by confirmation using liquid chromatography-tandem mass spectrometry. Six of the maize beers were obtained from Kibera slums in Nairobi County. Aflatoxin contamination was detected in six unrecorded beers (10%), but in none of the recorded wines. Remarkably, three of the aflatoxin positive samples were from the Kibera slums.The mean concentration of aflatoxins in the positive samples was 3.5 μg/L (range 1.8–6.8 μg/L), corresponding for an average consumption of 500 mL (1 standard drink) to a margin of exposure (MOE) of 36 (range: 15–58), which is considered as ‘risk’. On the other hand, the alcoholic strength of the aflatoxin positive samples had a mean of 4.3% vol (range 3.5–4.8%) corresponding to a MOE of 2.5 (range of 2.2–3.0) for the equivalent consumption volume. While aflatoxins pose a risk to the consumer, this risk is about 10 times lower than the risk of ethanol.The Joint FAO/WHO Expert Committee on Food Additives sets no acceptable daily intake for aflatoxins since they are genotoxic carcinogens and instead recommends for the reduction of aflatoxin dietary exposure as an important public health goal, particularly in populations who consume high levels of any potentially aflatoxins-contaminated food. Nevertheless, ethanol still posed a considerably higher risk in the unrecorded beers examined. However, consumers should be informed about aflatoxins, as these are an involuntary and unknown risk to them. In addition, producers should be educated about measures to reduce aflatoxins in alcoholic beverages.     

Occurrence and molecular identification of anisakid nematodes isolated from Pacific cod (Gadus macrocephalus) caught off Korea

Anisakids nematodes from Pacific cod (Gadus macrocephalus) in Korea were investigated and their molecular identification was conducted, to assess the epidemiological role of Pacific cod in human anisakidosis in Korea. Totally 238 Pacific cod were caught from 5 different areas around Korean peninsula. Fish were dissected and carefully examined for collecting nematodes. PCR-RFLP and the subsequent sequencing were conducted for molecular identification of those nematodes. A high prevalence of infection (193/238, 81.1%) in Pacific cod was observed, and 1694 nematodes were collected. 79.1% (1340/1694) of the nematodes were found freely in the body cavity of Pacific cod, and the rest of them (20.9%, 354/1694) were in the digestive tract or attached to other organs. PCR-RFLP analysis using HinfI and RsaI restriction enzymes revealed 3 different banding patterns corresponding to Anisakis pegreffii, Hysterothylacium aduncum and hybrid genotype (Anisakis simplex × A. pegreffii), respectively. Of 1694 nematodes, 1280 (75.6%) were identified as A. pegreffii and 406 (24.0%) were H. aduncum. A. pegreffii occupied 84.0% (1125/1340) of the nematodes in the body cavity and 40.0% (132/330) of them in the digestive tract, but no nematodes were found in Pacific cod muscles.     

Multiple mycotoxin co-occurrence in maize grown in three agro-ecological zones of Tanzania

In this study, the co-occurrence of multiple mycotoxins in maize kernels collected from 300 households' stores in three agro-ecological zones in Tanzania was evaluated by using ultra high performance liquid chromatography/time-of-flight mass spectrometry (TOFMS) with a QuEChERS-based procedure as sample treatment. This method was validated for the analysis of the main eleven mycotoxins of health concern that can occur in maize: aflatoxin B₁ (AFB₁), aflatoxin B₂ (AFB₂), aflatoxin G₁ (AFG₁), aflatoxin G₂ (AFG₂), ochratoxin A (OTA), deoxynivalenol (DON), fumonisin B₁ (FB₁), fumonisin B₂ (FB₂), HT-2 toxin, T-2 toxin and zearalenone (ZEN). From each zone one major maize producing district for home consumption was chosen and 20 villages for each district were randomly selected for sampling. All mycotoxins of health concern, except for T-2 toxin, were detected in the maize samples. Particularly high levels of AFB₁ (50%; 3–1,081 μg kg⁻¹), FB₁ (73%; 16–18,184 μg kg⁻¹), FB₂ (48%; 178–38,217 μg kg⁻¹) and DON (63%; 68–2,196 μg kg⁻¹) were observed. Some samples exceeded the maximum limits set in Tanzania for aflatoxins or in European regulations for other mycotoxins in unprocessed maize. Eighty seven percent of samples were contaminated with more than one mycotoxin, with 45% of samples co-contaminated by carcinogenic mycotoxins, aflatoxins and fumonisins. Significant differences in contamination pattern were observed among the three agro-ecological zones. The high incidence and at high levels (for some) of these mycotoxins in maize may have serious implications on the health of the consumers since maize constitute the staple food of most Tanzanian population. Effective strategies targeting more than one mycotoxin are encouraged to reduce contamination of maize with mycotoxins.