NovaSil clay intervention in Ghanaians at high risk for aflatoxicosis. I. Study design and clinical outcomes

A 3-month double-blind and placebo-controlled, phase IIa clinical trial was conducted in Ghana to investigate the safety, tolerance and aflatoxin-sorption efficacy of dietary NovaSil (NS). Volunteers (507 subjects) were clinically screened to evaluate their general health, pregnancy status and blood AFB₁–albumin adduct levels. Of these subjects, 177 were randomly assigned to three groups: high-dose (HD), low-dose (LD) and placebo-control (PL) groups receiving 3.0, 1.5 and 0 g NS day^?1 in capsules. Trained study-monitors supervised NS capsule administration to participants and recorded side-effects daily. Physical examinations were performed monthly. Blood and urine samples were collected for laboratory analysis. Approximately 92% of the participants (162 of 177) completed the study and compliance rate was over 97%. Overall, 99.5% of person?×?time reported no side-effects throughout the study. Mild to moderate health events (～0.5% of person?×?time) were recorded in some participants. Symptoms included nausea, diarrhea, heartburn and dizziness. These side-effects were statistically similar among all three groups. No significant differences were shown in hematology, liver and kidney function or electrolytes in the three groups. These findings demonstrate that NS clay is apparently safe and practical for the protection of humans against aflatoxins in populations at high risk for aflatoxicosis.     

Non-invasive detection of aflatoxin-contaminated figs using fluorescence and multispectral imaging

Agricultural products are prone to aflatoxin (AF)-producing moulds (Aspergillus flavus, A. parasiticus) during harvesting, drying, processing and also storage. AF is a mycotoxin that may cause liver cancer when consumed in amounts higher than allowed limits. Figs, like other agricultural products, are mostly affected by AF-producing moulds and these moulds usually produce kojic acid together with AF. Kojic acid is a fluorescent compound and exhibiting bright greenish yellow fluorescence (BGYF) under ultraviolet (UV) light. Using this fluorescence property, fig-processing plants manually select and remove the BGYF+ figs to reduce the AF level of the processed figs. Although manual selection is based on subjective criteria and strongly depends on the expertise level of the workers, it is known as the most effective way of removing AF-contaminated samples. However, during manual selection, workers are exposed to UV radiation and this brings skin health problems. In this study, we individually investigated the figs to measure their fluorescence level, surface mould concentration and AF levels and noted a strong correlation between mould concentration and BGYF and AF, and BGYF and surface. In addition to a pairwise correlation, we proposed a machine-vision and machine-learning approach to detect the AF-contaminated figs using their multispectral images under UV light. The figs were classified in two different approaches considering their surface mould and AF level with error rates of 9.38% and 11.98%, respectively.     

In Vitro Efficacy of Myxococcus fulvus ANSM068 to Biotransform Aflatoxin B(1)

Aflatoxin B(1) (AFB(1)) is commonly found in cereals and animal feeds and causes a significant threat to the food industry and animal production. Several microbial isolates with high AFB(1) transformation ability have been identified in our previous studies. The aim of this research was to characterize one of those isolates, Myxococcus fulvus ANSM068, and to explore its biotransformation mechanism. The bacterial isolate of M. fulvus ANSM068, isolated from deer feces, was able to transform AFB(1) by 80.7% in liquid VY/2 medium after incubation at 30 °C for 72 h. The supernatant of the bacterial culture was more effective in transforming AFB(1) as compared to the cells alone and the cell extract. The transformation activity was significantly reduced and eradicated after the culture supernatant was treated with proteinase K, proteinase K plus SDS and heating. Culture conditions, including nitrogen source, initial pH and incubation temperature were evaluated for an optimal AFB(1) transformation. Liquid chromatography mass spectrometry (LCMS) analyses showed that AFB(1) was transformed to a structurally different compound. Infrared analysis (IR) indicated that the lactone ring on the AFB(1) molecule was modified by the culture supernatant. Chromatographies on DEAE-Ion exchange and Sephadex-Molecular sieve and SDS-PAGE electrophoresis were used to determine active components from the culture supernatant, indicating that enzyme(s) were responsible for the AFB(1) biotransformation. This is the first report on AFB(1) transformation by a strain of myxobacteria through enzymatic reaction(s).     

The individual and combined effects of deoxynivalenol and aflatoxin b(1) on primary hepatocytes of cyprinus carpio

Aflatoxin B(1) (AFB(1)) and deoxynivalenol (DON) are important food-borne mycotoxins that have been implicated in animal and human health. In this study, individual and combinative effects of AFB(1) and DON were tested in primary hepatocytes of Cyprinus carpio. The results indicated that the combinative effects of AFB(1) and DON (0.01 μg/mL AFB(1) and 0.25 μg/mL DON; 0.02 μg/mL AFB(1) and 0.25 μg/mL DON; 0.02 μg/mL AFB(1) and 0.5 μg/mL DON) were higher than that of individual mycotoxin (P < 0.05). The activity of AST, ALT and LDH in cell supernatant was higher than that of control group (P < 0.05) when the mycotoxins were exposed to primary hepatocytes for 4 h. The decreased cell number was observed in tested group by inverted light microscopy. The mitochondrial swelling, endoplasmic reticulum dilation and a lot of lipid droplets were observed in primary hepatocytes by transmission electron microscope. Therefore, this combination was classified as an additive response of the two mycotoxins.     

Reducing human exposure to aflatoxin through the use of clay: A review

Innovative sorption strategies for the detoxification of aflatoxins have been developed. NovaSil clay (NS) has been shown to prevent aflatoxicosis in a variety of animals when included in their diet. Results have shown that NS clay binds aflatoxins with high affinity and high capacity in the gastrointestinal tract, resulting in a notable reduction in the bioavailability of these toxins without interfering with the utilization of vitamins and other micronutrients. This strategy is being evaluated as a potential remedy for acute aflatoxicosis, and as a sustainable human intervention for aflatoxins via the diet. Phase I and II clinical trials confirmed the apparent safety of NS for further study in humans. A recent study in Ghanaians at high risk for aflatoxicosis has indicated that NS (at a dose level of 0.25%) is effective in decreasing biomarkers of aflatoxin exposure and does not interfere with the levels of serum vitamins A and E, and iron and zinc. In summary, enterosorption strategies/therapies based on NS clay are promising for the management of aflatoxins and as a sustainable public health intervention. The NS clay remedy is novel, inexpensive and easily disseminated. Based on the present research, aflatoxin sequestering clays should be rigorously evaluated in vitro and in vivo, and should meet the following criteria: (1) favourable thermodynamic characteristics of mycotoxin sorption, (2) tolerable levels of priority metals, dioxins/furans and other hazardous contaminants, (3) safety and efficacy in multiple animal species, (4) safety and efficacy in long-term studies, and (5) negligible interactions with vitamins, iron and zinc and other micronutrients.     

超导量点—免疫荧光法快速测定粮食中黄曲霉毒素B1的方法验证

以超导量点为荧光探针,建立了一种超导量点-免疫荧光快速测定粮食中黄曲霉毒素B1的方法。采用多种方式评价了该方法与高效液相色谱法及酶联免疫吸附法检测稻谷及玉米样品的结果一致性,以验证该方法的准确性,同时对该方法的重复性和台间差异进行了考察。结果表明,超导量点-免疫荧光法对稻谷和玉米等粮食样品的检测结果与高效液相色谱法和酶联免疫法一致,表明该方法准确可靠,同时该方法两台仪器间的检测结果无显著性差异,且重复性好。     

弱碱高温法对花生粕脱毒及酶解效果的影响

本文主要研究了弱碱高温处理法去除花生粕中黄曲霉毒素的效果,并对去毒后花生粕的酶解效果进行了研究.研究结果表明:弱碱高温处理对原料中的黄曲霉毒素有较好的去除效果并有利于酶解的进行,花生粕经过121 ℃、pH 10、60 min处理,黄曲霉毒素的破坏率高达84.50 %,最终酶解上清液中黄曲霉毒素的含量低至0.344 ng/mL;而此时酶解液中蛋白质回收率比对照组的提高率为27.44 %,氨态氮含量比对照组的提高率为57.70 %.