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One of the significant challenges facing modern medicine is the rising rate of antibiotic resistance, which impacts public health, animal health, and environmental preservation. Evaluating antibiotic resistance in wildlife and their environments is crucial, as it offers essential insights into the dynamics of resistance patterns and promotes strategies for monitoring, prevention, and intervention. Klebsiella and Raoultella genera isolates were recovered from fecal samples of wild animals and environmental samples using media without antibiotic supplementation. Antibiograms were performed for 15 antibiotics to determine the phenotypic resistance profile in these isolates. Extended-spectrum β-lactamase (ESBL) production was tested by the double-disc synergy test, and one ESBL-producing K. pneumoniae isolate was screened by PCR and whole-genome sequencing. Biofilm production was analyzed using the microtiter plate method. A total of 23 Klebsiella spp. and 3 Raoultella spp. isolates were obtained from 312 fecal samples from wild animals, 9 Klebsiella spp. and 4 Raoultella spp. isolates were obtained from 18 river and stream water samples, and 4 Klebsiella spp. and 3 Raoultella spp. isolates from 48 soil samples. Regarding antibiotic resistance, only one isolate of K. pneumoniae from soil samples was an ESBL-producer and showed resistance to six antibiotics. This isolate harbored multiple β-lactams genes (blaCTX-M-15, blaTEM-1, blaSHV-28, and blaOXA-1), as well as genes of resistance to quinolones, sulfonamides, tetracycline, aminoglycosides, and chloramphenicol, and belonged to the lineage ST307. Most of the Klebsiella spp. and Raoultella spp. isolates were biofilm producers (except for one Klebsiella isolate), and 45.6% were weak biofilm producers, with the remaining being moderate to strong biofilm producers. We can conclude that antibiotic resistance is not widespread in these environment-associated isolates, which is a positive epidemiological outcome. However, identifying a single ESBL-K. pneumoniae isolate should serve as a warning of potential hotspots of resistance emergence. [ABSTRACT FROM AUTHOR]

Incorporating antioxidants into cosmetics is the mainstay for developing new products to mitigate skin aging. However, identifying novel multifunctional antioxidant ingredients with additional relevant properties that block the skin hallmarks of aging is a very striking strategy. Many natural compounds, including xanthones, have demonstrated biologically notable properties. In particular, 1,2-dihydroxy-9H-xanthen-9-one (1,2-DHX) has inhibitory activity against skin enzymes, and metal-chelating and radical-scavenging activities. Therefore, 1,2-DHX is an attractive molecule for cosmetic purposes. With this goal in mind, the anti-inflammatory, antioxidant, and anti-allergic potentials of 1,2-DHX were investigated. 1,2-DHX demonstrated anti-inflammatory properties by inhibiting the synthesis of specific pro-inflammatory mediators, including interleukin-6 (IL-6) and prostaglandin E2 (PGE2), in human macrophages. This xanthone did not elicit sensitization reactions and did inhibit allergic reactions triggered by a strong skin allergen, suggesting its potential as an anti-allergic compound. 1,2-DHX also revealed mitochondrial antioxidant activity by mitigating rotenone-induced oxidative stress in macrophages by up to 40%. Overall, 1,2-DHX displayed a safety profile and noteworthy biological activities, highlighting its multifunctional profile as an active cosmetic ingredient with anti-inflammatory, antioxidant, and anti-allergic properties. [ABSTRACT FROM AUTHOR]

The pursuit of cosmetic ingredients with proven efficacy and safety that meet consumer needs drives the advancement of new products. Ascorbic acid (AA) is utilized in cosmetic products, predominantly for its potent antioxidant properties. Nonetheless, its instability compromises its efficacy. In this work, ascorbyl 2-O-glucoside persulfate (AAGS) was synthesized, characterized, and evaluated regarding its safety profile and potential bioactivities and the results were compared to AA and its glycoside AAG. Pre-formulation studies were performed to assess the stability of the compounds and their compatibility with typical excipients commonly used in topical formulations. AAGS did not affect the metabolic activity of keratinocyte, macrophage, and monocyte cell lines, up to 500 µM. AAGS also exhibited a non-prooxidant and non-sensitizing profile and anti-allergic activity by impeding the allergen-induced maturation of THP-1 cells. When compared to AA and AAG, AAGS was shown to be more stable at pH values between 5 and 7, as well as superior thermostability and photostability. AAGS demonstrated higher stability in metal solutions of Fe(II) and Mg(II) than AA. AAGS demonstrated similar DPPH radical scavenging activity compared to AA. These results provide useful information for the development of new AA derivatives, highlighting AAGS as a novel cosmetic ingredient. [ABSTRACT FROM AUTHOR]

Simple Summary: The present work primarily focuses on the monitoring of antimicrobial resistance from fecal Escherichia coli from wildlife, an important environmental task due to the spread of resistant bacteria. In total, 128 E. coli isolates recovered from 66 wild animals were analyzed. Their resistance was tested against 17 antibiotics. An approximate percentage of 22.1% of the animals was found to carry multidrug-resistant E. coli, and 0.93% carried strains producing extended-spectrum β-lactamase (ESBL). The highest resistance was observed against ampicillin; all of the isolates were susceptible to amikacin and carbapenems. Therefore, such findings bring concerns about the dissemination of resistant bacteria among wildlife and any further impacts on public health. Antimicrobial resistance (AMR) surveillance in fecal Escherichia coli isolates from wildlife is crucial for monitoring the spread of this microorganism in the environment and for developing effective AMR control strategies. Wildlife can act as carriers of AMR bacteria and spread them to other wildlife, domestic animals, and humans; thus, they have public health implications. A total of 128 Escherichia coli isolates were obtained from 66 of 217 fecal samples obtained from different wild animals using media without antibiotic supplementation. Antibiograms were performed for 17 antibiotics to determine the phenotypic resistance profile in these isolates. Extended-spectrum β-lactamase (ESBL) production was tested using the double-disc synergy test, and 29 E. coli strains were selected for whole genome sequencing. In total, 22.1% of the wild animals tested carried multidrug-resistant E. coli isolates, and 0.93% (2/217) of these wild animals carried E. coli isolates with ESBL-encoding genes (blaCTX-M-65, blaCTX-M-55, and blaEC-1982). The E. coli isolates showed the highest resistance rates to ampicillin and were fully susceptible to amikacin, meropenem, ertapenem, and imipenem. Multiple resistance and virulence genes were detected, as well as different plasmids. The relatively high frequency of multidrug-resistant E. coli isolates in wildlife, with some of them being ESBL producers, raises some concern regarding the potential transmission of antibiotic-resistant bacteria among these animals. Gaining insights into antibiotic resistance patterns in wildlife can be vital in shaping conservation initiatives and developing effective strategies for responsible antibiotic use. [ABSTRACT FROM AUTHOR]

Xanthones are a class of heterocyclic compounds characterized by a dibenzo-γ-pyrone nucleus. Analysis of their mode of action in cells, namely uncovering alterations in gene expression, is important because these compounds have potential therapeutic applications. Thus, we studied the transcriptional response of the filamentous fungus Neurospora crassa to a group of synthetic (thio)xanthone derivatives with antitumor activity using high throughput RNA sequencing. The induction of ABC transporters in N. crassa, particularly atrb and cdr4, is a common consequence of the treatment with xanthones. In addition, we found a group of genes repressed by all of the tested (thio)xanthone derivatives, that are evocative of genes downregulated during oxidative stress. The transcriptional response of N. crassa treated with an acetophenone isolated from the soil fungus Neosartorya siamensis shares some features with the (thio)xanthone-elicited gene expression profiles. Two of the (thio)xanthone derivatives and the N. siamensis-derived acetophenone inhibited the growth of N. crassa. Our work also provides framework datasets that may orientate future studies on the mechanisms of action of some groups of xanthones.

Xanthones are a class of heterocyclic compounds characterized by a dibenzo-γ-pyrone nucleus. Analysis of their mode of action in cells, namely uncovering alterations in gene expression, is important because these compounds have potential therapeutic applications. Thus, we studied the transcriptional response of the filamentous fungus Neurospora crassa to a group of synthetic (thio)xanthone derivatives with antitumor activity using high throughput RNA sequencing. The induction of ABC transporters in N. crassa, particularly atrb and cdr4, is a common consequence of the treatment with xanthones. In addition, we found a group of genes repressed by all of the tested (thio)xanthone derivatives, that are evocative of genes downregulated during oxidative stress. The transcriptional response of N. crassa treated with an acetophenone isolated from the soil fungus Neosartorya siamensis shares some features with the (thio)xanthone-elicited gene expression profiles. Two of the (thio)xanthone derivatives and the N. siamensis-derived acetophenone inhibited the growth of N. crassa. Our work also provides framework datasets that may orientate future studies on the mechanisms of action of some groups of xanthones.