The interactions of Fusarium graminearum PG-Fg1 and its main trichothecenes with the 28 Trichoderma isolates were studied in vitro. The antagonistic effect assessed by dual-culture tests showed that Trichoderma isolates arrested the growth of PG-Fg1 after contact, overgrew the PG-Fg1 colony and inhibited the production of deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), and 15-acetyldeoxynivalenol (15-ADON) by up to 95.3%, 99.4%, and 99.6%, respectively. PG-Fg1 was hard to overgrow Trichoderma for further extension. Additionally, the inhibitory effects on PG-Fg1 by the Trichoderma metabolites, including volatiles and non-volatiles, were also investigated. Most of the Trichoderma isolates produced metabolites which inhibited PG-Fg1 growth and mycotoxins production. Specifically, Trichoderma non-volatiles and volatiles showed Fusarium growth inhibition rates ranging from 7% to 72% and 3% to 32%, respectively. Notably, non-volatile compounds from two isolates and volatiles from one isolate up-regulated the expression of DON biosynthesis genes (tri4 and tri5), leading to increased production of DON, 3-ADON, and 15-ADON. This study highlights the potential risk posed by certain Trichoderma strains as microbial agents, which can stimulate toxigenic fungi to produce higher levels of mycotoxins. Based on our results and previous reports, when selecting Trichoderma species as biocontrol agents against Fusarium graminearum, its effects on mycotoxins production should be carefully assessed, particularly given observed stimulatory impacts.

Zearalenone (ZEN), a mycotoxin produced by Fusarium species, widely contaminates grains and feed, posing a serious threat to animal and human health. Traditional physical and chemical detoxification methods face challenges, including low efficiency, high costs, and nutrient loss. In contrast, enzymatic biodegradation has emerged as a research hotspot due to its high efficiency, specificity, and environmental friendliness. Lactone hydrolase can specifically hydrolyze the lactone ring of ZEN, converting it into a low-toxicity or non-toxic degradation product, thereby demonstrating significant potential for application in ensuring the safety of food, feed, and agricultural products. In recent years, with advancements in enzyme engineering and various biological technologies, remarkable progress has been made in ZEN-degrading enzyme research. Novel and highly efficient enzyme genes have been discovered through gene mining, while directed evolution and rational design have improved catalytic efficiency and stability. Additionally, immobilization techniques and formulation optimization have enhanced industrial applicability. This review, based on practical application needs, establishes a comprehensive evaluation system integrating enzyme characteristics, modification technologies, and process applicability, aiming to provide actionable theoretical guidance for the large-scale application of biological detoxification technologies.

C-type lectins (CTLs) are a class of proteins containing carbohydrate recognition domains (CRDs), which are characteristic modules that recognize various glycoconjugates and function primarily in immunity. CTLs have been reported to affect growth and development and positively regulate innate immunity in Tribolium castaneum. However, the regulatory mechanisms of TcCTL16 proteins are still unclear. Here, spatiotemporal analyses displayed that TcCTL16 was highly expressed in late pupae and early adults. TcCTL16 RNA interference in early larvae shortened their body length and narrowed their body width, leading to the death of 98% of the larvae in the pupal stage. Further analysis found that the expression level of muscle-regulation-related genes, including cut, vestigial, erect wing, apterous, and spalt major, and muscle-composition-related genes, including Myosin heavy chain and Myosin light chain, were obviously down-regulated after TcCTL16 silencing in T. castaneum. In addition, the transcription of TcCTL16 was mainly distributed in the hemolymph. TcCTL16 was significantly upregulated after challenges with lipopolysaccharides, peptidoglycans, Escherichia coli, and Staphylococcus aureus. Recombinant CRDs of TcCTL16 bind directly to the tested bacteria (except Bacillus subtilis); they also induce extensive bacterial agglutination in the presence of Ca²⁺. On the contrary, after TcCTL16 silencing in the late larval stage, T. castaneum were able to develop normally. Moreover, the transcript levels of seven antimicrobial peptide genes (attacin2, defensins1, defensins2, coleoptericin1, coleoptericin2, cecropins2, and cecropins3) and one transcription factor gene (relish) were significantly increased under E. coli challenge and led to an increased survival rate of T. castaneum when infected with S. aureus or E. coli, suggesting that TcCTL16 deficiency could be compensated for by increasing AMP expression via the IMD pathways in T. castaneum. In conclusion, this study found that TcCTL16 could be involved in developmental regulation in early larvae and compensate for the loss of CTL function by regulating the expression of AMPs in late larvae, thus laying a solid foundation for further studies on T. castaneum CTLs.