A green analytical method based on a terpene-derived deep eutectic solvent (DES) was developed for the simultaneous extraction of aflatoxins (AFB1, AFB2, AFG1, AFG2) and citrinin (CIT) from colored and white rice, followed by ultra-high-performance liquid chromatography with fluorescence detection (UHPLC-FLD) Among the screened terpene-based DES systems, borneol: menthol (1:3) exhibited superior extraction efficiency and was selected for DES-based liquid–liquid microextraction prior to UHPLC-FLD analysis. Key extraction parameters were optimized using response surface methodology, resulting in optimal conditions of 1.5 mL sample extract, 250 µL DES, and 7.3 M KOH. The method showed excellent linearity (R² ≥ 0.997), low limits of detection (0.11–0.37 µg/kg for aflatoxins and 7.66–8.27 µg/kg for CIT), low limits of quantification (0.35–1.24 µg/kg for aflatoxins and 25.54–27.56 µg/kg for CIT), satisfactory recoveries (80%–110%), and acceptable precision (RSDr and RSDwr < 20%). Application to 80 commercial rice samples revealed low AFB1 contamination, while AFB2, AFG1, AFG2, and CIT were not detected. The environmental sustainability and practical applicability of the method were supported by AGREE and BAGI scores of 0.55 and 67.5, respectively. Overall, the proposed DES-based microextraction method provides an environmentally sustainable and practical approach for the simultaneous extraction of aflatoxins and CIT from rice prior to their chromatographic determination.

Rice is highly vulnerable to colonization by mycotoxigenic fungi during storage in warm and humid climates, where multiple fungal species frequently coexist. Among these, Aspergillus flavus and Penicillium citrinum are of major concern due to their production of aflatoxin B1 (AFB1) and citrinin (CIT), respectively. However, there is only limited understanding of how fungal interactions influence the growth kinetics and mycotoxin biosynthesis in rice ecosystems. Therefore, this study examined the combined effects of temperature (20-40 degrees C), water activity (aw; 0.87-0.97), and co-culture on growth and toxin production on a rice-based medium using the A. flavus and P. citrinum strains with contrasting toxigenic capacities. Primary and secondary growth models were applied to estimate the optimal radial growth rate (mu opt), reciprocal optimal lag time (1/lambda opt), and cardinal aw parameters (awopt and awmin), while Lotka-Volterra modelling was used to quantify the competitive interactions. Based on the results, in monoculture, A. flavus had a broader thermal niche than P. citrinum, with the latter failing to grow at 40 degrees C. The cardinal aw parameters remained consistent across strains. Under co-culture, mu opt and 1/lambda opt were influenced strongly by temperature and aw, with the greatest interaction effects at 30 degrees C. In contrast, awopt and awmin remained largely unchanged, indicating that competition modified the growth dynamics rather than the intrinsic physiological moisture thresholds. Frequently, intra-species co-culture stimulated toxin biosynthesis, whereas interspecific co-culture caused strain-and environment-dependent suppression or induction. The Lotka-Volterra coefficients indicated competitive coexistence rather than exclusion. Overall, fungal interactions significantly modulated growth efficiency and mycotoxin production, while leaving the core aw limits stable, highlighting the importance of incorporating microbial interactions into predictive mycology and rice storage risk assessment.

Maize (Zea mays L.) is a staple crop in Nigeria, playing a crucial role in ensuring national food security. However, it is highly susceptible to fungal contamination and mycotoxin production, which pose serious health risks. Despite increasing concern, data remain limited on mycotoxin contamination in maize from North-West Nigeria. This study aimed to investigate the occurrence of major mycotoxins and to characterize aflatoxin-producing Aspergillus section Flavi isolates associated with stored maize in this region. A total of 21 maize samples were collected from major grain markets across seven states: Jigawa, Kaduna, Kano, Katsina, Kebbi, Sokoto, and Zamfara. Fungal contamination and mycotoxin levels were evaluated using culture-based techniques and enzyme-linked immunosorbent assay, with aflatoxin levels in highly contaminated samples confirmed using high-performance liquid chromatography. The predominant fungi belonged to the Aspergillus section Flavi, followed by the Aspergillus sections Aspergillus and Nigri, and Rhizopus spp. Total aflatoxins were present in 80.9 % (n = 17) of the samples, with 42.8 % (n = 9) exceeding Nigeria’s regulatory limit of 4 µg/kg and 28.6 % (n = 6) surpassing the European Union (EU) maximum limit of 10 µg/kg. Fumonisins were present in 85.7 % of samples, although all concentrations were below the EU maximum limit of 4000 µg/kg. Ochratoxin A was identified in 61.9 % of the samples, albeit at low concentrations in several cases. The analysis of the Aspergillus section Flavi isolates revealed that 50 % were aflatoxigenic. All toxigenic isolates were identified as A. flavus, while the non-toxigenic strains were A. oryzae and A. tamarii. These findings highlight widespread contamination of maize in North-West Nigeria by aflatoxins and aflatoxigenic fungi, raising public health concerns. Future efforts should prioritize improving pre- and post-harvest practices, strengthening regulations, and implementing regular monitoring to mitigate mycotoxin contamination.

The objective of this study was to determine the kinetics of growth and citrinin production by Penicillium citrinum RC582 in purple glutinous rice grains ('Leum Pua' glutinous rice). A full factorial design was applied, examining four water activity (aw) levels (0.80, 0.85, 0.90, or 0.95) and three storage temperatures (20 °C, 30 °C, or 37 °C) over 21 days. Fungal growth was estimated based on the ergosterol content, with primary and secondary models applied to describe the growth and toxin production kinetics. The Gompertz model was used to estimate lag time and maximum growth rate (μmax). The highest μmax was found at 0.95 aw at 30 °C, whereas no growth occurred at 0.80 aw across all tested temperatures and 0.85 aw under 37 °C. The cardinal model predicted that the minimum aw required for growth (awmin) ranged from 0.796 to 0.850, while the optimal aw (awopt) ranged from 0.927 to 0.951, depending on the storage temperature. The maximum citrinin production (154 μg/g) was recorded at 0.95 aw at 30 °C, while no citrinin was detected at aw below 0.80, regardless of storage temperature, even after 21 days. Quadratic regression analysis revealed that lag time was significantly affected by aw, with temperature showing no significant effect, whereas μmax and citrinin production were influenced by temperature and aw. These findings should provide valuable guidance for developing targeted mycotoxin management strategies and intervention protocols for optimizing the storage conditions of purple glutinous rice.

Aflatoxins, known for their potent carcinogenic and mutagenic properties, pose a major threat to human and animal health. Due to the impacts of climate change, aflatoxin contamination has emerged as a critical food safety issue, necessitating the development of effective detoxification strategies to mitigate its severe health risks. The current isolated, identified, and characterized bacterial strains from peanut-growing soils that are capable of degrading aflatoxin B1 (AFB1). Coumarin was used as a selective carbon source during isolation. Bacterial isolate AD02 had the highest AFB1 degradation efficiency (88.85%). Morphological and genetic analyses confirmed AD02 as a Gram-negative, rod-shaped bacterium closely related to Pseudomonas knackmussii. Optimization studies using a Box-Behnken design showed that initial pH significantly affected AFB1 degradation, with the optimal conditions identified as pH 7, 25 degrees C, and 24 h of incubation, resulting in approximately 90% AFB1 degradation. Additionally, P. knackmussii AD02 simultaneously degraded a mixture of AFB1, AFB2, AFG1, and AFG2. A mechanistic study of AFB1 degradation revealed the role of extracellular enzymes, particularly in proteinaceous and membrane-associated components. The mechanism for AFB1 degradation involved the hydrolytic cleavage of the lactone ring in the coumarin moiety, followed by the cleavage of the cyclopentenone ring and the elimination of double bonds in the furan and coumarin moieties. The in silico predictions indicated that this bacterium could metabolize AFB1 into a non-mutagenic and non-carcinogenic intermediate product. This study represents the first report on aflatoxin degradation by P. knackmussii, highlighting its potential as an effective biological agent for aflatoxin detoxification.

Chili and pepper products are basic components of Myanmar cuisine. Mycotoxins in dried chili are major concerns for some countries due to poor post-harvest practices and insufficient enforcement of food control standards. This research investigated aflatoxins (AFs) and ochratoxin A (OTA) contamination in dried chili products, examined the mycobiota’s ability to produce these toxins, and assessed exposure from dried chili consumption. Sixty-eight samples of five types of dried chili were collected from markets and factories in the Yangon region during two different periods. Samples were analyzed for AFs and OTA using ELISA, revealing contamination levels of 97% for AFs and 91% for OTA. Of the 66 positive samples, 37.9% and 56.1% exceeded the Myanmar FDA's maximum limit (ML) of 20 μg/kg for AFs and the EU's limit of 10 μg/kg. Myanmar lacks ML for OTA, 16.1% of 62 samples exceeded the EU's limit of 20 μg/kg for chili powder. Regarding microbiological quality, 74% of samples exhibited fungal loads exceeding 104 CFU/g. Dominant mycobiota included Aspergillus spp. (76%), Penicillium spp. (21%), and Rhizopus spp. (3%), with Aspergillus section Flavi and Nigri. were identified as primary producers of AFs and OTA, respectively. Margin of Exposure (MOE) values for AFs, ranging from 246.9 to 277.8, were significantly lower than the threshold (≥10,000), indicating public health concern associated with dried chili consumption. Moreover, the estimated liver cancer risk ranged from 0.042 to 0.047 cases/year/100,000 people, indicating significant health risks. Although MOE values for OTA exceeded the safe thresholds for neoplastic effects (≥10,000), 97.5th percentile values of 1,945.3 and 1,730.3 were below this limit, indicating a potential health concern. These findings highlight the need for regulatory bodies to set OTA limits for dried spices. Further research on mycotoxin surveillance in other dried commodities in Myanmar is essential to ensure food quality and safety for consumers.

In recent years, pigmented rice, often referred to as functional rice, has attracted increasing attention due to its perceived health benefits arising from an abundance of phytochemicals. However, there is limited information on the occurrence and risks of mycotoxins due to long-term consumption of pigmented rice. This study assessed the co-occurrence and contamination levels of aflatoxins, citrinin (CIT), and ochratoxin A (OTA) in various pigmented rice samples sourced from Thailand, and also evaluated the potential health risks for consumers. The results indicated varying levels of mycotoxin contamination among the different tested pigmented rice varieties, with aflatoxin B1 (AFB1) being the most prevalent (39.1 %), followed by CIT (17.3 %) and OTA (14.5 %). The co-occurrences of AFB1-CIT and CIT-OTA were the most prevalent combination observed in the pigmented rice samples. Although the AFB1 and CIT levels remained below regulatory limits, some samples had OTA levels exceeding these limits, though by a small percentage. Furthermore, the anthocyanin content in pigmented rice showed a weak positive correlation with the AFB1 level (p < 0.05). The estimated risk of liver cancer incidence associated with the consumption of pigmented rice containing AFB1 was in the range 0.012-0.061 cases/100,000 persons/year, depending on consumption rate and behavior. The risk posed by CIT exposure was considered negligible. However, the exposure assessments suggested a potential risk of OTA exposure, particularly in scenarios with higher consumption rates. Cumulative risk assessment of AFB1-OTA co-occurrence indicated an amplified health risk compared to single mycotoxin exposure. These findings offer valuable evidence, encouraging further research aimed at mitigating the risks associated with mycotoxin contamination in pigmented rice.

This research investigates the efficacy of Spirogyra sp. biomass as an effective adsorbent for the removal of AFB1 and OTA from aqueous solutions. Several factors, including contact time, adsorbent dosage, pH level, and initial mycotoxin concentration, were analyzed to evaluate their impact on adsorption efficacy. The optimal contact time for equilibrium was determined at 60 min, during which the TPA obtained a 91% reduction in AFB1 and 68% removal of OTA. Although increasing the adsorbent dosage improved effectiveness, excessive quantities led to particle aggregation, hence diminishing adsorption performance. The optimal dosage of 5.0 mg/mL optimized the efficacy and use of resources. Adsorption was more efficacious at acidic to neutral pH levels (5–6), enhancing the accessibility of functional groups on the biomass. Kinetic analysis indicated that adsorption process followed a pseudo second-order model, whereas isotherm studies demonstrated a heterogeneous adsorption mechanism, with the Freundlich model providing the optimal fit. The TPB exhibited enhanced adsorption capacities for both mycotoxins, offering a viable solution for mitigating mycotoxin contamination in food and feed. These findings illustrate the significance of biomass treatment techniques in improving mycotoxin removal efficacy and suggest the potential of algal biomass in food safety applications.

Penicillium setosum, a member of the Penicillium section Lanata-divaricata, is known for its ability to produce high levels of patulin. However, there is a notable lack of information regarding the influence of environmental factors on the growth and patulin production in fruit juice of this species. In this study, we investigated the impacts of temperature (25, 30, 35, or 40 °C), initial pH value (3, 5, or 7), and incubation time (2, 4, or 6 days) on the growth and patulin production in pineapple juice of the selected P. setosum strain HR9-5. The modified Gompertz model was applied to estimate the maximum growth rate and lag time prior to growth. This strain had the highest growth rate with the shortest lag time within the temperature range 30–35 °C, with an initial pH range of 3–5. Furthermore, it had the greatest biomass dry weight and patulin production at 35 °C with an initial pH of 3, and at 25 °C with an initial pH of 7, respectively. The growth rate and lag time prior to growth of P. setosum HR9-5 were significantly influenced by the initial pH, whereas the biomass dry weight was strongly affected by temperature and incubation time. Additionally, all factors and their interactions had a significant impact on patulin production. This study provided the first report on the effect of environmental factors on growth and patulin production by P. setosum in pineapple juice. These findings can contribute to formulating effective prevention strategies to control the growth of P. setosum and subsequent patulin production in pineapple and other fruit juices.

Aflatoxins and aflatoxigenic fungi are hazardous to food security and safety since mycotoxins and related fungi in cereals significantly affect animal and human health. The relatively high frequency of aflatoxigenic Aspergilli isolates in corn samples remains a concern. Accordingly, we randomly collected corn samples from 10 farms in northern and central Thailand (TM1-TM10) and aimed to detect aflatoxigenic fungi using our recently developed methods: dichlorvos-ammonia (DV-AM) and whole-agar extraction methods. When we placed 100 grains from each sample on 20 agar dish cultures (five grains per dish) to monitor the emergence of fungal colonies, the presence ofAspergillus niger and A. flavus, with an emergence frequency of 1-8 and 1-7 per 100 grains, respectively, was detected. Some isolates of A. flavus produced aflatoxin B-1 and B-2 in the culture media, indicating typical features of aflatoxigenic A. flavus, whereas the non-aflatoxin-producing isolates produced kojic acid, thereby suggesting that they belong to Aspergillus section Flavi. Chemical analysis revealed aflatoxin B-1 and B-2 contamination in some grains and sporadic contamination with fumonisin B-1. Therefore, continuous monitoring and surveillance are required owing to the prevalence of mycotoxigenic fungi in corn.

Pigmented rice has gained interest for its nutritional and health benefits attributed to its bioactive compounds. Despite these advantages, the vulnerability of pigmented rice to mycotoxin contamination poses a major concern. This study examined the mycobiota of seven Thai pigmented rice varieties, with a focus on fungi capable of producing ochratoxin A (OTA) and citrinin. The study analyzed 110 pigmented rice samples and found that the Aspergillus section Aspergillus was predominant (50 - 82.35%), followed by Penicillium species (12.50 - 70.59%). One isolate of A. carbonarius from Aspergillus section Nigri (1/112) and two isolates from Aspergillus section Circumdati (2/61) - A. steynii and A. flocculosus - produced OTA. However, none of the Penicillium species produced OTA, though citrinin production was notable in P. citrinum (128/280). The study found that the Black Jasmine rice and Red Jasmine rice varieties were more susceptible to mycotoxin production, while the Luem Pua glutinous rice and Hom Nil rice varieties displayed more resistance to the accumulation of both mycotoxins. These findings should guide targeted strategies to mitigate mycotoxin risks and ensure the safety of pigmented rice in the food chain.

Heat-resistant molds (HRMs) are important spoilage fungi of heat-processed fruit products worldwide. Ascospores of HRMs are widely distributed in the soil in which fruits are grown and are often found associated with raw fruit materials. To date, there is little available information on the distribution of HRMs in the soil and on their heat resistance. Thus, this study determined the presence and characterized the heat resistance of HRMs in soil samples from pineapple and sugarcane fields in Thailand. HRMs were detected in all soil samples, and the most dominant species was Aspergillus with 50-99.2% relative abundance. Other isolates, in descending order of frequency, were Penicillium, Talaromyces, Hamigera, and Paecilomyces. Then, 100 representative HRM isolates were identified based on a combination of morphological characteristics and ITS sequences. They were classified into 5 genera and 24 species. The heat resistance of ascospores aged 30 days produced by selected HRMs was qualitatively determined in a glucose-buffered solution. Based on their log reductions after heat shock at 75°C for 30 min, they were classified as less, moderately, or highly heat-resistant ascospores. HRMs belonging to A. chevalieri, A. denticulatus, A. siamensis, A. laciniosus, A. fennelliae, A. spinosus, Paec. niveus, H. pallida, and T. macrosporus produced high heat-resistant ascospores. In addition, soil physicochemical properties significantly influenced the prevalence of HRMs, depending on the fungal genus. The thermal resistance of ascospores was significantly and positively correlated to available phosphorus, whereas it was negatively correlated to soil pH. The results of this study confirmed the presence of HRMs in soils and potential HRM contamination, especially in fruits growing in acidic or high-nutrient soils, or both.

Mycotoxin co-occurrence compromises the safety of food crops worldwide. Environmental factors, as well as fungal interaction, can substantially influence the infectivity of mycotoxigenic fungi and their subsequent production of multi-mycotoxin. Here, we investigated the mutual effects of the co-culture of ochratoxigenic and aflatoxigenic Aspergillus strains on the co-production of ochratoxin A (OTA) and aflatoxin B1 (AFB1). Single cultures of ochratoxigenic A. carbonarius and A. alliaceus grew optimally at 25 °C, whereas aflatoxigenic A. flavus grew optimally at 35 °C. The maximum levels of OTA and AFB1 were achieved at 25 °C, whereas mycotoxin production decreased at 35 °C. During competitive growth of the ochratoxigenic and aflatoxigenic isolates, inhibition or stimulation of mycotoxin production was dependent on the fungal strain, temperature, and the ratio of the spore concentration. Aspergillus carbonarius and A. alliaceus generally produced OTA, with similar patterns of relative OTA levels at all temperatures. AFB1 production by A. flavus in the presence of ochratoxigenic Aspergillus species was inhibited at 25 °C and stimulated at 35 °C. These results indicated that the temperature, presence of other mycotoxigenic Aspergillus species, and ratio of the initial spore concentration significantly contributed to the co-production of OTA and AFB1.

Dispersive liquid–liquid microextraction (DLLME) was optimized for the simultaneous extraction of aflatoxins (AFB1, AFB2, AFG1, and AFG2) from powdered senna leaves and pods. Detection was performed using high-performance liquid chromatography with fluorescence detection (HPLC-FLD) and pre-column derivatization. The parameters affecting the DLLME extraction efficiency were evaluated. Chloroform (200 µL) was used as an extraction solvent, 500 µL of distilled water was used as a dispersive solvent, and the extraction was performed at pH 5.6 with no salt added. The optimized method was validated using leaves and pods according to the European Commission guidelines. The linear range for all aflatoxins was 2–50 µg/kg, with values for regression coefficients of determination exceeding 0.995. The recoveries of spiked senna leaves and pods were in the ranges of 91.77–108.71% and 83.50–102.73%, respectively. The RSD values for intra-day and inter-day precisions were in the ranges of 2.30–7.93% and 3.13–10.59%, respectively. The limits of detection and quantification varied in the ranges of 0.70–1.27 µg/kg and 2.13–3.84 µg/kg, respectively. The validated method was successfully applied for the quantification of aflatoxins in 60 real samples of dried senna leaves and pods.

The contamination and spoilage of heat-treated fruit juices by heat-resistant mold ascospores present significant challenges to the food industry. Understanding effective strategies to mitigate this contamination is vital for ensuring the shelf-life and microbial safety of heat-treated fruit juices. This study investigated the thermal resistance of ascospores from different heat-resistant mold species, including Aspergillus laciniosus, A. chevalieri, A. denticulatus, A. siamensis, Hamigera pallida, and Talaromyces macrosporus, isolated from pineapple and sugarcane field soils. Ascospores inactivation kinetics in pineapple juice under heat treatment (75–97 °C) were analyzed using log-linear and Weibull models. Among these species, A. laciniosus displayed the highest heat resistance (δ-value: 104.59 min at 85 °C), while A. siamensis exhibited the lowest (δ-value: 3.39 min at 80 °C). Furthermore, A. laciniosus, the most heat-resistant species, showed notable tolerance to sanitizers. The most effective inactivation was achieved using 1.0% (w/v) sodium hypochlorite for 15 min. Chlorine dioxide, however, was generally ineffective and even activated dormant ascospores in some cases. The combination of hot water (65 °C for 5 min) with sanitizer increased ascospore reduction in most species but did not achieve the 3-log reduction required by the European Standard N13697. This study revealed a correlation between ascospore resistance to heat and chlorine dioxide, offering significant findings for practical inactivation strategies.

Occurrence of mycotoxins in staple foods is a major threat to attaining food safety in developing countries. The study investigated multi-mycotoxin contamination for the first time in Nepalese maize along with the incidence of molds in 45 samples of maize used as human food from 45 districts of Nepal. The samples were analyzed quantitatively for the presence of five different mycotoxins (total aflatoxins (AF), total fumonisins (FUM), ochratoxin (OT), zearalenone (ZEA) and (DON) deoxynivalenol) using the competitive direct ELISA technique. The most frequent occurrences were for DON (100%) and AF (78%) followed by FUM and ZEA (both 76%) and OT (62%). Interestingly, all the samples contained at least two mycotoxins while at least three or more mycotoxins were found in 87% of the samples. The most commonly reported binary, ternary and quaternary combinations were DON+AF, AF+FUM+DON and AF+FUM+ZEA+DON, respectively. The mean percentage kernel mold infection was 35.33% with Fusarium, Aspergillus, Rhizopus and Penicillium genera being the predominant molds. Six different species of Aspergillus and a single species of Fusarium were identified. The estimated daily intake, margin of exposure and risk of liver cancer from consuming maize were 30.46 ng/kg bw/day and 5.58 and 0.38 cancer cases/year/100,000 population, respectively. Since maize is the second-most consumed cereal in Nepal, the contamination levels of various mycotoxins and the incidence of molds identified in the study suggests that stricter control is needed to safeguard the health of the substantial population consuming maize as a staple diet.

This study aimed to evaluate the effectiveness of A. oryzae in inhibiting aflatoxin B1 (AFB1) and ochratoxin A (OTA) production by A. flavus and A. carbonarius, respectively, under shifting temperatures. A. oryzae was tested on different agar, namely coconut cream agar (CCA) and chili-based agar to figure out the variation in the effectiveness of A. oryzae on the most appropriate medium for A. flavus and A. carbonarius to produce mycotoxin and under natural condition where they are predominantly found. On CCA, the temperatures applied were 20, 30, 35, 40, 20/30, 20/35, and 20/40 °C, while on chili-based agar, the temperatures imposed were 20, 40, and 20/40 °C, at varied water activity of 0.92 and 0.97aw. The findings indicated that A. oryzae was much more effective in inhibiting the growth of A. flavus rather than A. carbonarius, yet it was able to inhibit higher OTA concentration than AFB1 at fluctuating temperatures on CCA as the most appropriate medium for A. flavus and A. carbonarius. A. oryzae effectively inhibited AFB1 and OTA at static temperature of 20 °C and water activity of 0.97aw on chili-based agar. Under fluctuating temperatures (20/40 °C), A. oryzae was also able to control mycotoxin, particularly OTA at high water activity (0.97aw).

Importance of the work: Each phenolic compound exhibits different effects on pigments and citrinin production.Objectives: To evaluate the effect of phenolic compounds in Hom Thong banana peel on pigments and citrinin production by Monascus purpureus. Materials & Methods:The effects were evaluated of Hom Thong banana peel and its phenolic compounds on fungal growth, pigment and lovastatin production and mycotoxin citrinin reduction by M. purpureus TISTR 3003.The total phenolics and flavonoids contents were determined at two stages of harvest (mature green and overripe).Results: Mature green Hom Thong banana peel contained the highest contents of total phenolics and flavonoids.The major phenolic compounds from banana peel were identified using high-performance liquid chromatography.Five phenolic compounds were found: gallic acid, caffeic acid, coumaric acid, catechin and rutin.Coumaric acid was found only in overripe banana peel and had an inhibitory effect on pigment production by M. purpureus.The highest lovastatin content (861.91 µg/g of dry weight) was produced from the optimized cultivation conditions of M. purpureus on overripe banana peel at 25°C for 32 d.The production of pigments and lovastatin was related to various factors, such as the ripening stage of the substrate and the incubation time.Main finding: Phenolics within Hom Thong banana peel can reduce citrinin production.Furthermore, banana peel can be used as a substrate for lovastatin and pigment production under solid state fermentation by M. purpureus as a safe, active ingredient in food products.

Incidence of mycotoxins in principal foods and grains is a major threat to achieving food safety but still remains one of the most underrated and ignored sources for food borne diseases, particularly in less developed countries. Furthermore, food insecurity together with ineffective government regulations and environmental conditions that favor fungal proliferation and toxin production merge together to make the people’s life even harder in countries like Nepal. Apart from wasting huge quantities of food every year, mycotoxins are associated with various acute and chronic health disorders including carcinogenic, mutagenic, estrogenic, digestive, vascular and nervous defects. Staple diets in less developed countries like Nepal are largely based on crops like maize, susceptible to mycotoxins which may ultimately lead to chronic health problems in large population. Although there is an immediate need to address the food safety challenges caused by mycotoxin contamination in cereal grains, studies so far in Nepal has been conducted mainly in aflatoxins in limited commodities only and very less efforts have been made to manage and mitigate the problems caused by mycotoxins in Nepal. Therefore, a thorough control of mycotoxins in overall food chain is essential to safeguard the health of the population which could be achieved by implementing stricter regulations, modern and scientific post-harvest operations, effective monitoring programs and raising necessary awareness among stakeholders. Int. J. Appl. Sci. Biotechnol. Vol 9(3): 152-159.

This study was aimed at determining the effect of temperature and water activity (aw) on the radial growth of Aspergillus flavus and A. carbonarius isolated from dried chili and their production of aflatoxin B1 (AFB1) and ochratoxin A (OTA), respectively. The isolates were grown on a synthetic chili-based medium, and growth and mycotoxin production were studied following a central composite design. The diameter of each colony was measured, and mycotoxins were extracted from the medium after 7 days of incubation at each different combination of temperature and aw. The analysis of variance results showed that temperature, aw, and their interaction had significant effects on growth and mycotoxin production. Response surface analysis showed that both strains were able to grow within a wide range of temperatures (22.93–37.07°C) and aw values (0.885–0.984), but production of AFB1 and OTA was not detected at 37.07°C or at aw below 0.900. The most favorable growth conditions for A. flavus were within a temperature range of 25–30°C and aw higher than 0.970, and maximum AFB1 production occurred at 22.93°C and aw of 0.984. For A. carbonarius, optimum growth and OTA production were observed at 22.93°C and aw of 0.970–0.984. Our results may be useful for controlling the growth of post-harvest mold in chili and preventing mycotoxin contamination of dried chili.