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Research background. Mango peel is a production waste and can cause environmental problems, but its nutritional value consists of bioactive compounds that could be beneficial for human health. The aim of this study is to determine the bioactive compounds, antioxidant and anti-inflammatory activities of mango peels and their use in muffins. Experimental approach. The content of polyphenols, carotenoids and total phenols as well as the antioxidant activity of mango peel extract were evaluated. The anti-inflammatory activity of the extract was investigated using Caco-2 cell assay. The mango peel powder was then incorporated into muffin formulations. The sensory properties of these fortified muffins were evaluated. The total phenolic content, antioxidant activity and anti-inflammatory properties of the muffin extracts and their bioaccessible fractions were also analysed. Results and conclusions. The mango peel contained quercetin, phenolic compounds, α-carotene, β-carotene and lutein, which have antioxidant potential. In Caco-2 cells exposed to induced inflammation, the mango peel powder extract (γ=10, 50 and 100 µg/mL) attenuated the production of reactive oxygen species (ROS), tumour necrosis factor-alpha (TNF-α) and interleukin-8 (IL-8), while maintaining cell viability. Muffins supplemented with 5 % mango peel powder showed good sensory properties, but not as good as those of plain muffins without mango peel powder. The total phenolic content and antioxidant activities in both the extract and the bioaccessible fraction of the supplemented muffins were higher than those observed in the standard muffins. Moreover, the extract and bioaccessible fraction of the supplemented muffins resulted in a higher reduction of ROS, IL-8 and TNF-α production in Caco-2 cells than those obtained from the standard muffins. Novelty and scientific contribution. This study is the first to investigate the protective effects of mango peel and muffins supplemented with mango peel powder against IL-1β-induced oxidative damage in Caco-2 cells. The results confirm that both mango peel and the supplemented muffins inhibited the production of inflammatory markers, including ROS and cytokines. These findings suggest that mango peel could be a valuable component of functional food formulations including dietary supplements.

In-house immunoaffinity column for aflatoxins (AFs) detection is firstly developed by Kasetsart University since 2011 i.e. the first IAC prototype, KU-AF01. Detection of aflatoxin B1 (AFB1) up to 200 ng is considered significantly efficient, but the production cost is considered high. The high cost was due to the cost of monoclonal antibody specific to aflatoxin and its supporting materials i.e. CNBr-activated sepharose 4B. Therefore, this study was aimed to improve the efficiency of in-house immunoaffinity colums by replacing CNBr-activated sepharose 4B with other supporting materials and to lower the ratio of antibody to supporting materials.  Response surface methodology (RSM) was applied to determine the optimum alternative supporting materials and the ratio. Results revealed that when compared with CNBr-activated sepharose 4B, all materials tested could recover higher than 80% AFB1, except the activated CH sepharose 4B. Results also indicated that the optimum ratio was 0.4 mg anti-aflatoxin monoclonal antibody to 204 µL CNBr-activated sepharose 4B. CNBr-activated sepharose 4B was considered to provide the best precision in recovering AFB1. KU-AF02 increased the ability to detect AFB1 to 500 ppb. The recovery of AFs in the reference materials using KU-AF02 was more than 96% successful, with HorRat value range of 0.34 – 0.76. The reference materials used were 2 levels of AFs in peanuts, i.e. 47.68 and 72.14 ng/g. In terms of quality control in IAC production, there were no significant differences among the 5 batches produced (p > 0.05). KU-AF02 demonstrated stable and constant percent recovery at 4 oC for up to 12 months (tested with standard 200 ppb AFB1). This study indicated that KU-AF02 could lower the ratio of supporting materials to the antibody and that KU-AF02 has high stability and has good ability for cleaning up AFs. Therefore, KU-AF02 is recommended to be used as an in-house immunoaffinity column for aflatoxin detection in Thailand.

Aflatoxins (AFs) and aflatoxin B1 (AFB1) intake through consumption of peanuts and peanut products were estimated from 60 samples. The samples were collected from 2 retail and 2 wholesale markets in Bangkok during November 2013–January 2014. The results showed that 80% of raw peanut samples were contaminated with AFs while 100% of roasted and ground peanuts samples were contaminated. The highest concentration of AFs was found in ground peanuts at 362.48 ng g−1 resulting in the highest mean concentration (68.22 ng g−1). According to a food consumption database, the average intake of AFs was estimated at 0.49, 0.40 and 2.13 ng/kg bw/day for raw, roasted and ground peanuts, respectively. The potential risk for cancer was estimated at 0.01–0.12 cancer/year/100,000 persons. The results suggest that the current situation of aflatoxins contamination in peanuts and peanut products (especially in ground peanuts) has an adverse effect on the health of the Thai population.