Anthropogenic activities enhance the concentration of trace elements in environment like highly carcinogenic Cadmium (Cd), which adversely affect the plant growth and development. They deliberately accumulate defense compounds e.g., flavonoids, terpenoids, and alkaloids to ensure resilience in such adverse conditions. Current study explores the adaptive evolution, structural complexity, and functional roles of Flavin Adenine Dinucleotide (FAD)-linked oxidase genes in widespread leading cash crop cotton. As a non-edible, hyperaccumulator halophyte crop, cotton is an excellent candidate for phytoremediation of Cd-polluted soils by manipulating stress resistant genetic material. They utilize FAD as a cofactor to drive oxidative reactions, including benzylisoquinoline alkaloid biosynthesis, which plays a critical role in cellular signaling pathways, stress responses and metabolic processes. A total of 387 FADs retrieved from four cotton species were distributed into seven families and twelve subfamilies. They underwent large scale expansion under intense purifying selection with lineagespecific gene loss and retention, reflecting their ongoing evolution for functional advancements to adopt altering environment. High throughput transcriptomic, functional enrichment and qRT-PCR validation revealed their multifaceted roles in growth, development and stress responses. Overexpression of GhBBE59 (BBE7) in Arabidopsis enhanced Cd tolerance by 25 % marked by a 20% reduction in malondiadehyde (MDA) and 25 % higher superoxide dismutase (SOD) activity compared to wild type plants. While its knockdown in cotton, reduced Proline accumulation by 60 % and increased electrolyte leakage by 2 fold, rendering plants hypersensitity to Cd stress. Transcriptomic and biochemical analyses demonstrated that BBE7 modulates redox homeostasis via 25% higher glutathione accumulation and hormonal crosstalk, mitigating oxidative damage. Functional analyses further revealed the pivotal role of BBE7 in regulation of oxidative stress, antioxidant production, epigenetic modifications and proline accumulation, thereby enhancing stress resilience. These findings hold substantial promise for reducing cadmium accumulation in soils, thereby mitigating its entry into the food chain and associated health risks. The implications of current study extend beyond fundamental research, addressing real-world challenges associated with environmental stresses and sustainable agriculture practices by enabling safer cultivation in polluted environments.

Herein, we report for the first time the incorporation of riboflavin as a bioactive additive in soy protein isolate films, along with investigating the impact of UV light treatment, thereby creating functional packaging material. Our investigation involves a comprehensive characterization of the films, including morphological, physicochemical, and mechanical properties, as well as their effectiveness as light barriers, antimicrobial potential, and biodegradation properties. The UV treatment of riboflavin/soy protein dispersions leads to the formation of films exhibiting minor water swelling and total soluble matter compared to those untreated with UV light, suggesting the development of a cross-linked network. Moreover, increased riboflavin content enhances the cross-linked network's robustness. The mechanical properties of the films exhibit a notable improvement with UV treatment and with increasing riboflavin content until a limit value, showcasing increased tensile strength and Young's modulus. Films showed homogeneous surfaces with an absence of pores and cracks and the ability to act as a barrier for oil passage. Films were assayed as a coating material for chia oil samples exposed to highintensity UV light, showing great protection capacity. It has been demonstrated that an increase in riboflavin concentration enhances the UV light-blocking properties, making these films promising candidates for storing light-sensitive food products while preserving their nutritional quality. In addition, antibacterial action against S. aureus was determined by disk diffusion assay. Furthermore, the films exhibited relatively short disintegration times under soil burial conditions, even after chemical modification. This research contributes valuable insights to the innovative field of sustainable food packaging materials.

Fluoride is widely found in groundwater, soil, animal and plant organisms. Excessive fluoride exposure can cause reproductive dysfunction by activating IL -17A signaling pathway. However, the adverse effects of fluoride on male reproductive system and the mechanisms remain elusive. In this study, the wild type and IL -17A knockout C57BL/6J mouse were treated with 24 mg/kg & sdot;bw & sdot;d sodium fluoride and/or 5 mg/kg & sdot;bw & sdot;d riboflavin-5 '-phos- phate sodium for 91 days. Results showed that fluoride caused dental fluorosis, increased the levels of ROS in testicular Leydig cells and GSSG in testicular tissue, and did not affect the iron and serum hepcidin levels in testicular tissue. Riboflavin alleviated above adverse changes, whereas IL -17A does not participate in the oxidative stress -mediated reproductive toxicity of fluoride. Based on this, TM3 cells were used to verify the injury of fluoride on Leydig cells. Results showed that fluoride increased mRNA levels of ferroptosis marker SLC3A2, VDAC3, TFRC, and SLC40A1 and decreased Nrf2 mRNA levels in TM3 cells. The ferroptosis inhibitor Lip -1 and DFO were used to further investigate the relationship between male reproductive toxicity and ferroptosis induced by fluoride. We found that the fluoride -induced decrease in cell viability, increase in xCT, TFRC, and FTH protein expression, and decrease in GPX4 protein expression, can all be rescued by Lip -1 and DFO. Similar results were also observed in the riboflavin treatment group. Moreover, riboflavin mitigated fluoride -induced increases in ROS levels and SLC3A2 protein levels. In all, our work revealed that riboflavin inhibited ferroptosis in testicular Leydig cells and improved the declined male reproductive function caused by fluoride. This study provides new perspectives for revealing new male reproductive toxicity mechanisms and mitigating fluoride toxicity damage.

Microbes can cause or accelerate metal corrosion, leading to huge losses in corrosion damages each year. Geobacter sulfurreducens is a representative electroactive bacterium in many soils, sediments, and wastewater systems. It has been confirmed to directly extract electrons from elemental metals. However, little is known about the effect of electron shuttles in G. sulfurreducens corrosion on stainless steel. In this study, we report that exogenous flavins promote iron-to-microbe electron transfer, accelerating microbial corrosion. G. sulfurreducens caused 1.3 times deeper pits and increased electron uptake (with 2 times increase of i corr ) from stainless steel when riboflavin was added to the culture medium. OmcS -deficient mutant data suggest that G. sulfurreducens utilizes riboflavin as a bound-cofactor in outer membrane c type cytochromes. The finding that, in the presence of microbes, riboflavin can substantially accelerate corrosion highlights the role of flavin redox cycling for enhanced iron-to-microbe electron transfer by G. sulfurreducens and provides new insights in microbial corrosion. (c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Main observation and conclusion The aminoglycoside antibiotic apramycin contains a unique bicyclic octose moiety, and biosynthesis of this moiety involves an oxidoreductase AprQ. Unlike other known Q series proteins involved in aminoglycosides biosynthesis, AprQ does not work with an aminotransferase partner, and performs a four-electron oxidation that converts a CH2OH moiety to a carboxylate group. In this study, we report mechanistic investigation of AprQ. We showed AprQ contains a flavin mononucleotide (FMN) cofactor, which is different from other known Q series enzymes that contain a flavin adenine dinucleotide (FAD) cofactor. A series of biochemical assays showed that AprQ is not a monooxygenase but a flavoprotein oxidase. Although molecular O-2 is strictly required for reaction turnover, four-electron oxidation can be achieved in the absence of O-2 in single turnover condition. These findings establish the detailed catalytic mechanism of AprQ and expand the growing family of flavoprotein oxidases, an increasingly important class of biocatalysts.