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Current antifungal interventions have often limited efficiency in treating fungal pathogens, particularly those resistant to commercial drugs or fungicides. Antifungal drug repurposing is an alternative intervention strategy, whereby new utility of various marketed, non-antifungal drugs could be repositioned as novel antifungal agents. In this study, we investigated "chemosensitization" as a method to improve the efficiency of antifungal drug repurposing, wherein combined application of a second compound (viz., chemosensitizer) with a conventional, non-antifungal drug could greatly enhance the antifungal activity of the co-applied drug. Redox-active natural compounds or structural derivatives, such as thymol (2-isopropyl-5-methylphenol), 4-isopropyl-3-methylphenol, or 3,5-dimethoxybenzaldehyde, could serve as potent chemosensitizers to enhance antifungal activity of the repurposed drug bithionol. Of note, inclusion of fungal mutants, such as antioxidant mutants, could also facilitate drug repurposing efficiency, which is reflected in the enhancement of antifungal efficacy of bithionol. Bithionol overcame antifungal (viz., fludioxonil) tolerance of the antioxidant mutants of the human/animal pathogen Aspergillus fumigatus. Altogether, our strategy can lead to the development of a high efficiency drug repurposing design, which enhances the susceptibility of pathogens to drugs, reduces time and costs for new antifungal development, and abates drug or fungicide resistance.

Featured Application: Salicylaldehyde and 4-isopropyl-3-methylphenol can be used as potential antifungal and anti-mycotoxigenic agents for crops/foods to be processed. Crops such as tree nuts, corn and peanut are highly susceptible to infestation by the aspergilli Aspergillus flavus or Aspergillus parasiticus and subsequent aflatoxin (AF) contamination, a serious threat to public food safety. Conventional control of the aspergilli has been through the application of fungicides; however, certain fungicides at sub-optimal doses have been correlated with increased production of mycotoxins including AF. Natural products (NP) have been a potential source of antifungal agents. In this study, we performed risk assessment testing, for which thirteen NP/derivatives (generally recognized as safe) were examined at sub-inhibitory concentrations to determine the enhancement of AF production in aspergilli. We found that benzaldehyde derivatives or thymol (THY) enhanced AF production in aspergilli, while 4-isopropyl-3-methylphenol (4I3M), a synthetic analog of the NP THY and carvacrol, or salicylaldehyde (SLD) exerted a potent antifungal or mycotoxin-inhibitory effect. In seed testing (corn, pistachio kernels), SLD effectively prevented fungal growth as a fumigant, while 4I3M completely inhibited AF production at ≥1.0 mM. Therefore, we concluded that NP/derivatives that do not have any significant environmental impact can be a potent source of antifungal or anti-mycotoxigenic agents, either in their nascent form or as leads for more effective derivatives; however, NP should be applied at optimum concentrations to prevent the abnormal enhancement of mycotoxin production by fungi. [ABSTRACT FROM AUTHOR]

The redox activities of polyaniline (PANI) are hindered by the instability of pernigraniline salt (PS) state which degrades into oligo‐aniline. In this work, the use of protic additives is examined to mitigate capacity fading and increase utilization of PANI in nonaqueous electrolytes. The protic additive propylene glycol, with its hydrogen‐bonding capabilities, stabilizes the PS PANI and promotes reversible redox reactions, facilitating high capacity and an extended cycle lifetime for applications in metal ion supercapacitors. The use of this protic nonaqueous electrolyte in a PANI–zinc device results in an energy density of 255 Wh kg−1 at a power density of 1.8 kW kg−1 and a robust cycle lifetime of 3,850 charge/discharge cycles. The PANI at a high current density of 6.5 mA cm−2 reaches a capacity of 257 mAh g−1, equivalent to 87% of the its theoretical capacity, showcasing the effectiveness of the protic additive in improving both capacity and cycle life in electrochemical supercapacitors. [ABSTRACT FROM AUTHOR]

The development of portable X‐ray detectors is necessary for diagnosing fractures in unconscious patients in emergency situations. However, this is quite challenging because of the heavy weight of the scintillator and silicon photodetectors. The weight and thickness of X‐ray detectors can be reduced by replacing the silicon layer with an organic photodetectors. This study presents a novel bithienopyrroledione‐based polymer donor that exhibits excellent photodetection properties even in a thick photoactive layer (~700 nm), owing to the symmetric backbone and highly soluble molecular structure of bithienopyrroledione. The ability of bithienopyrroledione‐based polymer donor to strongly suppress the dark current density (Jd ~ 10−10 A cm−2) at a negative bias (−2.0 V) while maintaining high responsivity (R = 0.29 A W−1) even at a thickness of 700 nm results in a maximum shot‐noise‐limited specific detectivity of Dsh* = 2.18 × 1013 Jones in the organic photodetectors. Printed organic photodetectors are developed by slot‐die coating for use in X‐ray detectors, which exhibit Dsh* = 2.73 × 1012 Jones with clear rising (0.26 s) and falling (0.29 s) response times upon X‐ray irradiation. Detection reliability is also proven by linear response of the X‐ray detector, and the X‐ray detection limit is 3 mA. [ABSTRACT FROM AUTHOR]

Preservatives deter microbial growth, providing crucial functions of safety and durability in composite materials, formulated products, and food packaging. Concern for human health and the environmental impact of some preservatives has led to regulatory restrictions and public pressure to remove individual classes of compounds, such as parabens and chromated copper arsenate, from consumer products. Bans do not address the need for safe, effective alternative preservatives, which are critical for both product performance (including lifespan and therefore life cycle metrics) and consumer safety. In this work, we studied both the safety and efficacy of a series of phenolic preservatives and compared them to common preservatives found in personal care products and building materials. We quantified antimicrobial activity against Aspergillus brasiliensis (mold) and Pseudomonas aeruginosa (Gram negative bacteria), and we conducted a hazard assessment, complemented by computational modeling, to evaluate the human and environmental health impacts of these chemicals. We found that octyl gallate demonstrates better antimicrobial activity and comparable or lower hazards, compared to current-use preservatives. Therefore, octyl gallate may serve as a viable small-molecule preservative, particularly in conjunction with low concentrations of other preservatives that act through complementary mechanisms.