Mould and mycotoxin contamination of pig feed in northwest Croatia

The aim of this study was to investigate the contamination of pig feed with moulds and the occurrence of mycotoxins. A total of 30 feed samples were collected at different animal feed factories in the north-western part of Croatia. Mycological analysis showed that the total number of moulds ranged from 1?×?10³ to 1?×?10⁵?cfu/g with samples contaminated with Aspergillus spp. (63?%), Penicillium spp. (80?%), and Fusarium spp. (77?%). A determination of aflatoxin B1 (AFB₁), ochratoxin A (OTA), zearalenone (ZEA), deoxynivalenol (DON), T-2 toxin (T-2) and fumonisin (FUM) concentration was done using the validated ELISA method. The mean concentrations of AFB₁ (0.5?±?0.6???g/kg), OTA (1.53?±?0.42???g/kg) and FUM (405?±?298???g/kg) were below the maximum levels or recommended values in the EU in all the investigated samples. The observed results indicated an increased contamination of pig feed with Fusarium mycotoxins DON and ZEA with mean concentrations of 817?±?447 and 184?±?214???g/kg, higher than recommended in 40 and 17?% of the analysed samples, respectively.     

Exposure to aflatoxin B<Subscript>1</Subscript> in Thailand by consumption of brown and color rice

This study assessed the aflatoxin B₁ (AFB₁) intake of the Thai population through consumption of contaminated brown and color rice. A total of 240 rice samples from two harvesting periods were collected in June/July 2012 (period I) and in December 2012/January 2013 (period II) and analyzed for AFB₁ by HPLC with fluorescence detection (limit of detection (LOD)?=?0.093 ng/g). Exposure assessment was based on AFB₁ levels in rice and food intake data for rice according to Thai National Consumption. Frequency and levels of AFB₁ were higher in period I (59 %, <LOD?=?26.61 μg kg^?1) than in period II (10 %, <LOD?=?3.51 μg kg^?1). Only one sample exceeded the Thai standard limit for total aflatoxin of 20 μg kg^?1, but 12 out of 240 rice samples exceeded the European Union maximum level for AFB₁ of 2 μg kg^?1. The data showed that the quality and safety of Thai rice largely comply with the requirement for both exports and domestic consumption. According to the Thai National Consumption data, the estimated AFB₁ intake via rice consumption in period I and period II was 0.80 and 0.12 μg kg^?1 bw day^?1, respectively. The potential risk for cancer, based on the recommendation of the JECFA, was estimated to be 0.011 person/year/100,000 people at a mean consumption. Although the risk via consumption of Thai rice seems to be low, the maximum levels of AFB₁ in this staple food suggest that careful monitoring and surveillance of AFB₁ contamination in rice is essential to ensure the safety of rice.     

Kinetic of orange pigment production from <Emphasis Type="Italic">Monascus ruber</Emphasis> on submerged fermentation

Pigments produced by species of Monascus have been used to coloring rice, meat, sauces, wines and beers in East Asian countries. Monascus can produce orange (precursor), yellow and red pigments. Orange pigments have low solubility in culture media and when react with amino groups they become red and largely soluble. The orange pigments are an alternative to industrial pigment production because the low solubility facilitates the downstream operations. The aim of this work was to study the kinetic on the production of orange pigments by Monascus ruber CCT 3802. The shaking frequency of 300 rpm was favorable to production, whereas higher shaking frequencies showed negative effect. Pigment production was partially associated with cell growth, the critical dissolved oxygen concentration was between 0.894 and 1.388 mgO₂ L^?1 at 30 °C, and limiting conditions of dissolved oxygen decreased the production of orange pigments. The maintenance coefficient (mo) and the conversion factor of oxygen in biomass (Yo) were 18.603 mgO₂ g _x ^?1  h^?1 and 3.133 g_x gO ₂ ^?1 and the consideration of these parameters in the oxygen balance to estimate the biomass concentration provided good fits to the experimental data.     

Aflatoxin B<Subscript>1</Subscript> contamination in feed from Puglia and Basilicata regions (Italy): 5 years monitoring data

During a 5-year period from 2010 to 2014, n = 919 samples of feed and raw materials were analyzed for aflatoxin B₁ (AFB₁) contamination using accredited ELISA screening methods. Only 0.76 % of these samples were non-compliant with maximum levels set by the European Union Regulation 32/2002. Non-compliant samples were mainly from the province of Bari (n = 3 samples, mean AFB₁ value 7.03 μg/kg), although the highest AFB₁ levels were found in two samples from the provinces of Foggia and Brindisi, at 32.6 ± 3.6 μg/kg and 31.0 ± 4.0 μg/kg, respectively. Mean AFB₁ levels in samples contaminated but compliant with the limits ranged from 1.4 to 2.2 μg/kg. Considering the great importance of climate conditions in mycotoxins production, during crops production and during the critical phases of materials storage and/or transport, to better understand the variability in contamination levels, the analytical results were reviewed in term of temperature and relative environmental humidity in the sampling areas. Correlations between aflatoxin B₁ levels in feed and these climate factors might explain seasonal and annual variations in contamination levels. The data from the present study provide useful suggestions for the organization of targeted monitoring plans and the protection of consumers, as well as for improvement in the quality standards of zootechnological activities and feed industry.     

Feasibility of 3D UV-C treatment to reduce fungal growth and mycotoxin loads on maize and wheat kernels

Fungal disease of grain crops is a concern for the agricultural industry, resulting in economic losses. Aside from severe yield losses, mycotoxigenic fungi such as Penicillium and Fusarium can produce harmful mycotoxins, including deoxynivalenol (DON), zearalenone (ZEN), and ochratoxin A (OTA). This proof-of-concept study explored the feasibility and effects of ultraviolet (UV) C light at 253.7 nm to reduce fungal and mycotoxin loads on model surfaces as well as on maize and wheat kernels using benchtop 2D and 3D illumination strategies. Reduction of Penicillium verrucosum (98.6%) and Fusarium graminearum (88.8%) on agar was achieved using a UV-C dose of 100 mJ cm^?2. Naturally occurring fungal growth resembling P. verrucosum on maize was reduced by 79% after exposure to 5000 mJ cm^?2. Similarly, fungal growth resembling F. graminearum on maize was reduced by 60% with 1000 mJ cm^?2. On wheat, significant reduction of fungal growth was not observed. Maximal reduction of DON (97.3%), ZEN (75.4%), and OTA (91.2%) on filter paper was obtained using 15,000 mJ cm^?2. The overall reduction of DON (30%; 14%), ZEN (52%; 42%), and OTA (17%; 6%) on maize and wheat, respectively, was lower than on filter paper. Moisture and crude protein content as well as percent germination of maize kernels were not affected by UV-C treatment up to 5000 mJ cm^?2. This study has shown that 3D UV-C treatment is a feasible option for reducing Fusarium and Penicillium growth on maize kernels and, at higher doses, decreasing ZEN by ~?50%.     

Mycotoxigenic fungi and mycotoxins associated with stored maize from different regions of Lesotho

Samples of stored maize from villages located in five different agroecological zones (southern lowlands, northern lowlands, Senqu river valley, foothills and mountains) of Lesotho were collected in 2009/10 and 2010/11 and assessed for contamination with toxigenic fungi. The water activity of all samples collected during the two seasons was <0.70. The total fungal populations of the maize from different regions in the two seasons was not significantly different (p?>?0.05). Fusarium verticillioides, F. proliferatum and F. subglutinans predominated in different regions in both seasons based on molecular analyses. In the 2009/10 season, the isolates of these species all produced FB₁, while in the 2010/11 season, very few produced FB₁. A. flavus isolates (2009/10) were recovered from mountains and Senqu river valley samples while the 2010/11 isolates were predominantly from the foothills and northern lowlands. The mountain isolates of Aspergillus section Flavi produced the highest levels of AFB₁ (20 mg kg^?1). Aspergillus parasiticus was only isolated from the foothills, Senqu river valley and southern lowlands samples, and the AFB₁ levels produced ranged from ‘none detected’ to 3.5 mg kg^?1. The Aspergillus ochraceous isolates were least frequently encountered in both seasons. In the 2009/10 season, the isolates from the northern lowlands produced ochratoxin A (OTA) in culture. No isolates of A. niger from different regions in both seasons produced any OTA. Multi-mycotoxin analyses of the maize samples were done for a range of mycotoxins. At least one sample from each region in both seasons was FB₁-positive. FB₁ levels for 2010/11 samples (7–936 μg kg^?1) were higher than in the 2009/10 season (2–3 μg kg^?1). In both seasons, the mountains registered the highest levels of FB₁. Deoxynivalenol (DON) was recovered from all the samples analysed, with the highest mean contamination of 1,469 μg kg^?1 in samples from the northern lowlands. Moniliformin (MON) was detected from all agroecological zones in the two seasons (5–320 μg kg^?1 in 2009/10; 15–1,205 μg kg^?1 in 2010/11). Emerging toxins such as fusaproliferin (FUS) and beauvericin (BEA) were also detected. OTA was not detected in any of the samples analysed. Only one 2009/10 sample in the Senqu river valley was positive for AFB₁. This is the first report on toxigenic fungi and multi-mycotoxin contamination of maize samples from subsistence farmers’ stores in different agroecological zones of Lesotho.     

Limited survey on aflatoxin contamination in rice

Aflatoxins (AFS) are toxic and carcinogenic fungal metabolites. Aflatoxin B1 is the most toxic and has been classified as a Group I carcinogen by the International Agency for Research on Cancer (IARC). Samples of imported rice were analyzed for their AFS content. Finley ground rice subsamples were extracted with water/methanol (100:150 v/v) followed by purification with Immunoaffinity columns (IAC). AFS purified from extracts were determined with RP-HPLC-FLD using post column electrochemical derivatization with a Kobra Cell. Concentrations of aflatoxin B1 and total AFS in test rice samples were ≤0.123 and ≤2.58 µg/kg, respectively. Tween 80 improved recoveries (86 and 106%) of aflatoxin B1 and aflatoxin G1 from brown rice. Recoveries of Aflatoxin B2 and aflatoxin G2 were substantially reduced (non-detected to 27%) by Tween 80 used in IAC cleanup of brown rice extracts. Visible dense growth of Aspergillus parasiticus (food isolate) occurred at 25 °C but higher aflatoxin B1amounts (23.9–39.3 µg/kg) accumulated when the mold grew at 37 °C in rice seeds stored for three weeks. It could be concluded that levels of aflatoxin B1 and total AFS in rice samples were within the permissible amounts of the EU and other international legislations.     

Occurrence of aflatoxins and its management in diverse cropping systems of central Tanzania

The staple crops, maize, sorghum, bambara nut, groundnut, and sunflower common in semi-arid agro-pastoral farming systems of central Tanzania are prone to aflatoxin contamination. Consumption of such crop produce, contaminated with high levels of aflatoxin B₁ (AFB₁), affects growth and health. In this paper, aflatoxin contamination in freshly harvested and stored crop produce from central Tanzania was examined, including the efficacy of aflatoxin mitigation technologies on grain/kernal quality. A total of 312 farmers were recruited, trained on aflatoxin mitigation technologies, and allowed to deploy the technologies for 2 years. After 2 years, 188 of the 312 farmers were tracked to determine whether they had adopted and complied with the mitigation practices. Aflatoxigenic Aspergillus flavus and aflatoxin B1 contamination in freshly harvested and stored grains/kernels were assessed. A. flavus frequency and aflatoxin production by fungi were assayed by examining culture characteristics and thin-layer chromatography respectively. AFB₁ was assayed by enzyme-linked immunosorbent assay. The average aflatoxin contamination in freshly harvested samples was 18.8 μg/kg, which is above the acceptable standard of 10 μg/kg. Contamination increased during storage to an average of 57.2 μg/kg, indicating a high exposure risk. Grains and oilseeds from maize, sorghum, and sunflower produced in aboveground reproductive structures had relatively low aflatoxin contamination compared to those produced in geocarpic structures of groundnut and bambara nut. Farmers who adopted recommended post-harvest management practices had considerably lower aflatoxin contamination in their stored kernels/grains. Furthermore, the effects of these factors were quantified by multivariate statistical analyses. Training and behavioral changes by farmers in their post-harvest practice minimize aflatoxin contamination and improve food safety. Moreover, if non-trained farmers receive mitigation training, aflatoxin concentration is predicted to decrease by 28.9 μg/kg on average.     

Isolation and molecular characterization of mycotoxigenic fungi in agarwood

Agarwood (Oudh), is often used by people in the Kingdom of Saudi Arabia. The Oudh has been mentioned in the Hadith and is traditionally used for its aroma (perfuming smell) and potential medicinal applications. The aim of the study was to isolate mycotoxigenic fungi that grow on agarwood and the factors and storage conditions that enhance their growth potential. In addition to the detection of associated mycotoxins like: Aflatoxin B1 (AFB₁) and ochratoxin A (OTA) from agarwood. Agarwood samples were collected from local markets of Jeddah governorate, Kingdom of Saudi Arabia. Standard dilution plate method was used for the isolation of fungi. Isolated fungi were identified based on morphological characteristics and confirmed using molecular biology techniques. AFB₁ and OTA were detected by High Performance Liquid Chromatography (HLPC). The results indicated that the most commonly isolated fungal genera were in the following descending order: Aspergillus, Penicillium, Fusarium and Rhizopus. Among Aspergillus genera, A. flavus and A. ochraceus were detected based on their morphology and confirmed by PCR using specific primers. It was also noted that AFB₁ was released by 15.3 and 55.0% of A. flavus and A. parasiticus isolates respectively with levels reaching up to 14.60 µg/L. The moisture content in the samples ranged from 3% to 10% affected fungal growth. AFB₁ was detected in 22 out of 50 of the samples. The maximum level of AFB₁ (50.7 µg/kg) was detected in samples with higher moisture content (12%) stored at a temperature of 32 °C. Aspergillus fungi were found to be the most predominant fungal genera found on agarwood. Moisture content (9–10%) and storage temperature (32 °C) stimulated fungal growth and their ability to produce mycotoxins. For this reason, storage conditions at the marketing place should be adequate in order not to provide a conducive environment for fungal growth which is associated with the mycotoxin production. In order to prevent fungal growth and mycotoxin production, it would be recommended to store agarwood at temperatures not exceeding 25 °C and moisture content of up to a maximum of 5–6%.     

Nutritional value of some algae from the north-western Mediterranean coast of Egypt

Fourteen taxa from Chlorophyta, Rhodophyta and Phaeophyta were collected from seven stations at different depths, along the north-western Mediterranean coast of Egypt during winter and summer 2006. Total carbohydrates (TCH), total protein (TPr), total lipids (TL), chlorophyll a, β-carotene, minerals and trace metals were determined in a total of 50 specimens. The concentrations of these components varied significantly with respect to the algal taxa and showed different patterns of distribution in the three classes. The content of TCH ranged from 5 to 20.9?%, being much higher for Cystoseira spinosa (20.9?%), TPr 3.86 to 27.65?% where Gelidium corneum showed the maximum value and TL content displayed wide variation (2.34 to 48.95?%), with Sargassum hornschuchii having the highest values. A minor component was β-carotene in all samples (1.80?2.50?×?10^?3 mg (100 g)^?1) which was much lower than in vegetables, in contrast to chlorophyll a concentrations which have attained high values (6.70?94.20 mg (100 g)^?1) and were lower than in vegetables. Mineral content was abundant in all samples and was higher than in common food and vegetables, whereas the measured trace metals all exceeded the permissible doses and were far from the accepted concentrations in the regulations of many countries. This limits their use in food consumption, except copper which recorded acceptable concentrations in the study. The maximum values of phosphorus (3,305 mg (100 g^?1), potassium (930 mg (100 g^?1) and calcium (3,070 mg (100 g^?1) were recorded in members of Chlorophyceae: Codium bursa, Udotea sp. and Udotea petiolata, whereas the red alga Rhodymenia ardissonei had the lowest concentrations in iodine (80 ppm) and sodium (1,450 mg (100 g)^?1) and the highest concentrations in the trace metals copper (3.89 ppm), nickel (13.14 ppm), zinc (38.87 ppm) and a relatively large amount of lead (41.60 ppm).     

Co-occurrence of five Fusarium toxins in corn-Dried Distiller’s Grains with Solubles in Thailand and comparison of ELISA and LC-MS/MS for fumonisin analysis

Dried Distiller’s Grains with Solubles (DDGS), a by-product of bio-ethanol production from maize and other cereals, is increasingly used as a feed additive. In this study, five Fusarium toxins, including fumonisin B₁ (FB₁), fumonisin B₂ (FB₂), deoxynivalenol (DON), zearalenone (ZEN) and beauvericin (BEA) were quantified by LC-MS/MS in 59 corn-DDGS samples. In addition, the fumonisin level in 30 randomly selected-samples was compared using an ELISA detection technique. No sample was free from mycotoxin contamination, and 50.8 % of the samples were co-contaminated with all five mycotoxins. Moreover, toxin levels were generally high, with mean levels of 9 mg kg^?1 FB₁, 6 mg kg^?1 FB₂, 1.2 mg kg^?1 DON, 0.9 mg kg^?1 ZEN, and 0.35 mg kg^?1 BEA. Maximum levels for FB₁ (143 mg kg^?1) and FB₂ (125 mg kg^?1) are of acute toxicological relevance. The ELISA method had a tendency to underestimate the fumonisin content when compared with LC-MS/MS. Finally, this is the first reported beauvericin contamination in corn-DDGS.     

Aflatoxin B1 and zearalenone in dairy feeds in Portugal, 2009–2011

This paper presents 3 years of data (2009–2011) on the occurrence of two mycotoxins, aflatoxin B₁ (AFB₁) and zearalenone (ZEA), in samples of feedstuff for dairy cows (n?=?963), ewes (n?=?42), and goats (n?=?131) produced in Portugal. AFB₁ was found in 15 samples of cow feed (1.6 %), 3 samples of ewe feed (2.3 %) and in 2 samples of goat feed (4.8 %). All but two samples contained AFB₁ at levels below the European Union maximum level (5 μg/kg). Nearly half (45 %) of the samples were contaminated with ZEA, but its levels were relatively low, at 5–136.9 μg/kg, well below the European Union guidance value (500 μg/kg).     

Evaluation of fungal contamination and mycotoxin production in maize silage

Agricultural activities involve daily use of maize silage as feed for livestock, which can be contaminated by mycotoxigenic molds. To evaluate fungal contamination, and the production of mycotoxins in maize silage we propose a multi-disciplinary approach utilizing PCR methods with genes of the aflatoxin (ver-1, omt-1 and apa-2), fumonisin (FUM1) and trichothecene (TRI6) biosynthesis pathways. To detect Aspergillus fumigatus, a 26S/intergenic spacer region of the rDNA complex was amplified. These specific PCR assays allowed three major groups of toxigenic fungi-like aflatoxin-producing Aspergilli, fumonisin and trichothecene-producing Fusaria, and the ubiquitous mold A. fumigatus, to be targeted. A multimycotoxin method is also proposed to simultaneously quantify seven mycotoxins (i.e., aflatoxin B₁, citrinin, deoxynivalenol, fumonisin B₁, gliotoxin, ochratoxin A, zearalenone) in maize silage by high-performance liquid chromatography coupled to mass spectrometry (HPLC–MS). These microbiological and analytical tools revealed three potentially toxigenic groups of fungi and A. fumigatus grown from mature maize silage (11 month old) that was collected in Normandy (France) and the mycotoxins aflatoxin B₁ (7.0–51.3 μg/kg), citrinin (10.1–14.2 μg/kg), deoxynivalenol (128.0–181.0 μg/kg) and gliotoxin (6.6–11.9 μg/kg). Results indicate that the combination of PCR and HPLC–MS can be used to assess fungal quality of maize silages.     

Aflatoxigenic strains of Aspergillus section Flavi isolated from marketed peanuts (Arachis hypogaea) in Algiers (Algeria)

The present study reports on the natural mycobiota occurring in Chinese peanuts marketed in Algiers, paying special attention to the incidence of Aspergillus section Flavi species that are potential producers of aflatoxins. The mean value counts of fungi ranged from 155 to 577 CFU/g dry matter (DM) and the predominant fungi were different species of the genus Penicillium (83.81–93.85 %) and Aspergillus belonging to section Flavi (2.73–73.96 %). Results indicated that 82 isolates (100 %) were aflatoxigenic. The Aspergillus section Flavi strains revealed that 65 isolates (79.27 %) were highly aflatoxigenic, producing four kinds of aflatoxins [AFB1 (0.846–3.330 μg/g), AFB2 (0.005–0.007 μg/g), AFG1 (0.008–1.595 μg/g), and AFG2 (0.005–0.010 μg/g)], whereas 17 isolates (20.73 %) synthetized low levels of one or two aflatoxins (AFB1 and AFG2). Aflatoxin production was also screened on Coconut Agar Medium (CAM), and the results were consistent with the HPLC analysis. Based on the combination of mycotoxins produced, five Aspergillus section Flavi chemotypes were established. Sclerotia production expressed a correlation to aflatoxigenicity. The total aflatoxins were detected in four analyzed samples at levels ranging from 0.71 to 25.50 μg/kg. Furthermore, the amplicons corresponding to the ITS1-5.8 S-ITS2 rDNA of six representative strains showed that four strains belonged to Aspergillus flavus, one to A. minisclerotigenes, and one to A. caelatus. The results obtained indicate that there is a possible risk factor posed by aflatoxins contamination of peanuts marketed in Algiers.     

The Mycotoxin Zearalenone Hinders <Emphasis Type="Italic">Candida albicans</Emphasis> Biofilm Formation and Hyphal Morphogenesis

Yeast–mold mycobiota inhabit several natural ecosystems, in which symbiotic relationships drive strategic pathoadaptation. Mycotoxins are metabolites produced by diverse mycotoxigenic fungi as a defense against yeasts, though at times yeasts secrete enzymes that degrade, detoxify, or bio-transform mycotoxins. The present study is focused on the in vitro inhibitory effects of zearalenone (ZEN), a F2 mycotoxin produced by several Fusarium and Gibberella species, on different microbial strains. ZEN exhibited no effect on the planktonic growth or biofilms of several Gram positive and negative bacteria at the tested concentrations. Remarkably, Candida albicans biofilm formation and hyphal morphogenesis were significantly inhibited when treated with 100 µg/mL of ZEN. Likewise, ZEN proficiently disrupted pre-formed C. albicans biofilms without disturbing planktonic cells. Furthermore, these inhibitions were confirmed by crystal violet staining and XTT reduction assays and by confocal and scanning electron microscopy. In an in vivo model, ZEN significantly suppressed C. albicans infection in the nematode Caenorhabditis elegans. The study reports the in vitro antibiofilm efficacy of ZEN against C. albicans strains, and suggests mycotoxigenic fungi participate in asymmetric competitive interactions, such as, amensalism or antibiosis, rather than commensal interactions with C. albicans, whereby mycotoxins secreted by fungi destroy C. albicans biofilms.     

Comparison between solid-state and powder-state alkali pretreatment on saccharification and fermentation for bioethanol production from rice straw

The efficacy of different concentrations of NaOH (0.25%, 0.50%, 0.75%, and 1.00%) for the pretreatment of rice straw in solid and powder state in enzymatic saccharification and fermentation for the production of bioethanol was evaluated. A greater amount of biomass was recovered through solid-state pretreatment (3.74 g) from 5 g of rice straw. The highest increase in the volume of rice straw powder as a result of swelling was observed with 1.00% NaOH pretreatment (48.07%), which was statistically identical to 0.75% NaOH pretreatment (32.31%). The surface of rice straw was disrupted by the 0.75% NaOH and 1.00% NaOH pretreated samples as observed using field-emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). In Fourier-transform infrared (FT-IR) spectra, absorbance of hydroxyl groups at 1,050 cm^?1 due to the OH group of lignin was gradually decreased with the increase of NaOH concentration. The greatest amounts of glucose and ethanol were obtained in 1.00% NaOH solid-state pretreated and powder-state hydrolyzed samples (0.804 g g^?1 and 0.379 g g^?1, respectively), which was statistically similar to the use of 0.75% NaOH (0.763 g g^?1 and 0.358 g g^?1, respectively). Thus, solid-state pretreatment with 0.75% NaOH and powder-state hydrolysis appear to be suitable for fermentation and bioethanol production from rice straw.     

Mycoflora and mycotoxin contamination of Roundup Ready soybean harvested in the Pampean Region, Argentina

A total of 89 freshly harvested soybean seed samples (Roundup Ready [transgenic] soybean cultivars) from the 2010/2011 crop season were collected from five locations in the Northern Pampean Region II, Argentina. These samples were analyzed for internal mycoflora, toxin production of isolated fungi, and for a range of mycotoxins. Mycotoxin analysis of aflatoxins (AFs), zearalenone (ZEA), fumonisins (FBs) and ochratoxin A (OTA) was done by HPLC-FLD (high performance liquid chromatography with postcolumn fluorescence derivatization), alternariol and alternariol monomethyl ether with HPLC-UV (HPLC with UV detection), trichothecenes (deoxynivalenol, nivalenol, T-2 toxin, HT-2 toxin, fusarenon X, 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol were analyzed by GC-ECD (gas chromatography with electron capture detector). Fungal colonization was more frequently found for samples from América, Saladillo and Trenque Lauquen than for samples from General Villegas and Trenel; a total of 1,401 fungal isolates were obtained from the soybean seeds. The most commonly identified fungal genera were Alternaria, Sclerotinia, Chaetomium, Cladosporium, Aspergillus, Penicillium, Phomopsis and Fusarium. Alternaria alternata, A.tenuissima, Aspergillus flavus, Penicillium citrinum, Fusarium verticillioides and F.semitectum were the predominant toxigenic fungal species. Mycotoxin production was confirmed for several isolates of toxigenic species, including Aspergillus flavus, A. parasiticus, Alternaria alternata, A.tenuissima, Fusarium graminearum, F semitectum and F. verticillioides. In particular, the percentage of mycotoxigenic Alternaria alternata (100 %), A.tenuissima (95 %) and aflatoxigenic strains of A. flavus (57 %) were remarkably high. Although none of the mycotoxins, AFs, ZEA, FBs, trichothecenes and OTA, were directly detected in samples of soybean seeds, the frequent presence of toxigenic fungal species indicates the risk of multiple mycotoxin contamination.     

Pre-harvest aflatoxins and <Emphasis Type="Italic">Aspergillus flavus</Emphasis> contamination in variable germplasms of red chillies from Kunri,Pakistan

Various cultivars of red chilli were collected from a small town named Kunri, located in the province Sindh, Pakistan. This town is a hub of red chilli production in Asia. A total of 69 samples belonging to 6 cultivars were obtained and analysed for the occurrence of aflatoxins and Aspergillus flavus, to explore the potential of resistant and susceptible germplasm. Aflatoxins were detected by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC), while A. flavus was isolated and identified using agar plate, blotter paper, deep freezing and dilution techniques. Molecular characterization using internal transcribed spacer (ITS) 1/4 and A. flavus specific FL1-F/R primers confirmed the identity of A. flavus. The data revealed that 67 and 75% samples contaminated with aflatoxin B₁ (AFB₁) and with A. flavus, respectively. A highly susceptible chilli cultivar was ‘Nagina’, showing 78.8% frequency of total aflatoxins (1.2–600 μg/kg) and a mean of 87.7 μg/kg for AFB₁ and 121.9 μg/kg for total aflatoxins. A. flavus was detected with 93% frequency and 2.14 × 10⁴ colony forming units. In contrast, cultivars ‘Kunri’ and ‘Drooping Type’ were found to be resistant, with low levels of aflatoxins and fungal counts. The study was conducted for the first time to explore two potential cultivars that were less susceptible towards A. flavus and aflatoxin contamination. These cultivars could be preferably cultivated and thereby boost Pakistan’s chilli production.     

First Report on Mould and Mycotoxin Contamination of Pistachios Sampled in Algeria

Mycotoxin contamination of pistachios represents a serious food safety hazard. The aim of this study was to evaluate fungal contamination and aflatoxin (AF) and ochratoxin A (OTA) occurrence in pistachio sampled in Algeria and to study the mycotoxigenic capacities of the isolates. A total of 31 pistachio samples were collected from retail outlets from different regions of Algeria. The most frequently found fungi were Penicillium spp. (38%), Aspergillus section Nigri (30%) and A. flavus (22%). A total of 56.5% of A. flavus isolates were able to produce AFB₁ and AFB₂. No A. section Nigri uniseriate isolate was OTA producer, whereas OTA production capacity was detected in 33.3% of the A. section Nigri biseriate. At least one of the potentially ochratoxigenic species was found in 64.5% of samples. Despite the high number of pistachio samples containing AFs and OTA-producing isolates, only two samples contained AFs (always below the EU maximum tolerable level) and only one sample showed OTA contamination. This is the first report on the occurrence of toxigenic moulds and mycotoxins in pistachios from Algerian market.     

Microbe‐mediated control of Aspergillus flavus in stored rice grains with a focus on aflatoxin inhibition and biodegradation

Biological control of mycotoxigenic fungi using antagonistic microbes is a promising alternative to agricultural chemicals for postharvest storage. In this study, we evaluated rice‐derived bacterial strains to identify biocontrol agents to inhibit Aspergillus flavus in stored rice grains. Consequently, we obtained three potential biocontrol strains (Microbacterium testaceum KU313, Bacillus megaterium KU143 and Pseudomonas protegens AS15) from 26 tested strains that were prescreened from the 460 strains isolated from rice grains. The three selected strains proved to be effective biocontrol agents showing antifungal activity against A. flavus and good colonisation ability on rice grains, along with inhibition of the fungal growth and aflatoxin production. In particular, P. protegens AS15 greatly inhibited the aflatoxins produced by A. flavus on rice grains to 8.68 (percent aflatoxin reduction relative to control = 82.9%) and 18.05 (68.3 %) ng g^?1 dry weight of rice grains, compared with the 50.89 and 56.97 ng g^?1 dry weight of rice grains of the MgSO₄ control at 1 and 2 weeks after inoculation, respectively. In addition, strain AS15 had a significant ability to not only degrade aflatoxin B₁ (the most harmful aflatoxin), but also utilise the toxin for bacterial growth in a nutrient‐deficient medium. Therefore, the selected bacterial strains could be environmentally sound alternatives for the management of A. flavus and aflatoxin production by reducing the fungal damage to stored rice grains. This would also reduce the human and animal health hazards associated with the consumption of fungus‐contaminated rice grains. To our knowledge, this is the first report of the potential of the bacterial species M. testaceum and P. protegens as biocontrol agents for controlling aflatoxigenic A. flavus on stored rice grains.