This study aimed to determine the dietary effects of honeybee pollen (BP) on growth parameters, intestinal microbiota, hepatic histoarchitecture, and intestinal histomorphometry of African catfish Clarias gariepinus juveniles. The feeding experiment was carried out in a recirculating aquaculture system under controlled conditions for 21 days to achieve more than a 10-fold increase in weight in fish from the control group. Fish were fed well-balanced commercial feed without any supplements and served as a reference group (group C) and other diets enriched with varying BP levels as 1% (BP1), 2% (BP2), and 3% (BP3). Results showed a significant (p < 0.05) effect of the dietary BP not only on the growth parameters (such as final body weight: 5.0 g to 6.6–7.5 g, weight gain: 0.23 g/d to 0.31–0.35 g/d, body length: 84.7 mm to 93.8–95.9 mm, and specific growth rate: 11.7%/d to 13.1–13.7%/d, group C vs. experimental groups, respectively) but also on the development of beneficially important gut microbiota, such as lactic acid-producing bacteria. In BP-enriched groups, an average of 45% higher body weight gain was observed compared to those reared in the control group. The histological analysis showed that dietary BP may have a positive effect on the development of the intestinal tract and may enhance the absorption of nutrients with the potential ability to maintain a normal hepatic histoarchitecture of the treated African catfish. The results obtained suggest the optimum level of BP additive to feed for African catfish should be 1%.
Deoxynivalenol (DON) is one of the most common trichothecene mycotoxins found in cereals, posing a significant hazard to food and feed safety. Insects, especially the yellow mealworm (Tenebrio molitor), offer promising alternative protein sources; however, their capacity to metabolise mycotoxins and the nutritional implications are still not fully understood. In this study, T. molitor larvae were reared for two weeks on diets containing DON at 663 or 913 µg/kg, and their biomass was analysed using Liquid Chromatography–Quadrupole Time-of-Flight Mass Spectrometry (LC-QTOF) for DON metabolites and free amino acids, as well as Gas Chromatography–Flame Ionization Detector (GC-FID) for fatty acid profiles. Larvae metabolised DON via multiple pathways, including sulfonation, glucuronidation, sulfation, glucosylation, and de-epoxidation, with a time- and dose-dependent shift towards glucosylation and de-epoxidation. DON exposure significantly reduced the levels of essential amino acids such as methionine, lysine, phenylalanine, and isoleucine, and lowered metabolic intermediates like aspartic and glutamic acid. Conversely, prolonged DON exposure increased linoleic acid levels in larval fat, indicating altered lipid metabolism. These findings demonstrate that T. molitor larvae detoxify DON but incur measurable metabolic costs, leading to changes in amino acid and fatty acid profiles. The dual effect—reduction of toxin levels and nutritional shifts—highlights both the potential and the challenges of using insects for sustainable feed production.
Deoxynivalenol (DON) is a prevalent mycotoxin in feed, raising concerns about its impact on animal health and feed safety. Insects such as yellow mealworm (Tenebrio molitor) may play a role in the biodegradation of DON-contaminated feed. This study presents the results of a two-week rearing experiment, where 19-week-old yellow mealworm larvae were fed diets with varying concentrations of DON. The larvae were divided into three groups (C, A, and B) that differed in the amount of mycotoxin added to the feed. Larval survival, body mass, and DON accumulation in larvae and their frass were evaluated. A statistical analysis revealed no significant differences in larval survival or body mass gain between the groups. The results point to the low accumulation of DON in larvae, reaching 13.13 ± 2.06 µg/kg (A) and 32.18 ± 4.20 µg/kg (B) after two weeks of feeding. Moreover, at the end of the experiment, DON was detected in larval frass at high concentrations of 507.65 ± 15.31 µg/kg (A) and 862.61 ± 18.53 µg/kg (B), suggesting that larvae are capable of effectively excreting this mycotoxin. The analyzed mycotoxin had no significant effect on larval survival or growth. Deoxynivalenol did not accumulate in the larval biomass and was excreted with frass. These findings enhance our understanding of the interactions between DON and yellow mealworm larvae and have potential implications for using insects in feed production and mycotoxin neutralization within ecosystems. Tenebrio molitor larvae tolerate DON-contaminated feed and effectively excrete the toxin, making them potential candidates for feed detoxification systems.
Zearalenone (ZEN) is an estrogenic mycotoxin produced by Fusarium spp. and commonly found in cereals and feed materials. This study evaluated the ability of Metschnikowia pulcherrima KKP 1368 biomass to reduce extractable ZEN under controlled buffered pH conditions (pH 3.50 and 7.00) selected as simplified conditions relevant to the porcine gastrointestinal environment. ZEN was quantified by LC-MS/MS, whereas LC-MS-QTOF was used as a qualitative/semi-quantitative screening approach for tentatively assigned transformation-related features. In the presence of yeast biomass, extractable ZEN was already lower than in the corresponding controls at the first sampling point, indicating a rapid biomass-associated effect. After 12 h, reductions relative to the corresponding controls reached 63.0% at pH 3.50 (p < 0.0001) and 51.6% at pH 7.00 (p = 0.0001). ZEN remained stable in control samples, and the strain remained viable under both pH conditions throughout incubation. LC-MS-QTOF detected several tentatively assigned features consistent with zearalanone, zearalenone-14-glucuronide, and zearalenol O-glucoside; these assignments require confirmation with authentic standards. Overall, M. pulcherrima KKP 1368 reduced extractable ZEN in a simplified buffered in vitro system, probably through rapid adsorption/reduced extractability and possible biotransformation. Further studies using biomass fractions or inactivated biomass, mass-balance experiments, authentic standards, and toxicological assays are needed to clarify the relative contribution of adsorption and transformation and to assess the practical relevance of this approach.