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Phaseolus lunatus (lima bean) has been a model organism to understand direct and indirect defenses against herbivores. We investigated the identity and diversity of endophytic fungi associated with young, mature and old leaves of lima bean in its natural environment. We recovered 758 isolates that were identified and classified in 142 fungal species from 66 genera, with Curvularia , Fusarium , Phomopsis , Alternaria and Colletotrichum being the most abundant and diverse Ascomycota genera. Our data revealed that species richness and diversity increased with leaf age, this factor being also important for the structure of the endophytic community. The occurrence patterns of fungal species was highly heterogeneous among leaves, and only fourteen species were recovered from all three foliar ages investigated. In vitro dual assays between endophytes and the plant pathogen Colletotrichum lindemuthianum revealed that most endophytes tested can inhibit the growth of this pathogen, suggesting their potential as biocontrol agents. [ABSTRACT FROM AUTHOR]

Abstract: Little is known about the dynamics of succession of fungi on limestone exposed in subtropical environments. In this study, the colonization of experimental blocks of compact and porous limestone by a fungal community derived from natural biofilms occurring on Structure X from the archaeological site of Becán (México), was studied using a cultivation-dependent approach after short-term (9 m) exposure in order to provide a preliminary insight of the colonization process under seminatural conditions. Microbial growth seen as the change of colour of stone surfaces to black/dark green was more abundant on the porous limestone. There was a fairly clear difference in microbial colonization between the onset of the experiment and the 6th month for both limestone types, but no significant increase in the colonization of coupons occurred between months 6 and 9. This could be related to the low rainfall expected for this period, corresponding to the dry season. A total of 977 isolates were obtained. From these, 138 sterile fungi were unidentified, 380 could only be assigned to the order Sphaeropsidales; the remaining isolates (459) were grouped into 27 genera and 99 different species. Nearly all detected fungal species belonged to the Ascomycota (90 %). Rare taxa (species represented by one to three isolates) included the recently described genus Elasticomyces, several species of genera Hyalodendron, Monodyctis, Papulospora, Curvularia, and Septoria. Other taxa were Minimedusa and Gliomastix luzulae, which have not been previously described for stone environments. Abundant fungi included several species of the common genera Cladosporium, Alternaria, and Taeniolella typical for a range of habitats. Succession of populations was observed for certain taxa, this shift in the composition of fungal communities was more evident in porous limestone. After 6 m of exposure, species of the genera Scolecobasidium, Hyalodendron, and Taeniolella were predominant, while after 9 m, the predominant species belonged to the genera Curvularia and Alternaria, particularly on porous stone. These results suggest that Curvularia and Alternaria replaced other fungi, due to a higher tolerance towards low levels of available water during the dry season. Higher levels of water within the porous stone, keep longer periods of microbial activity, minimizing the impact of desiccation. This study contributes to understand the diversity of fungal communities in stone surfaces in subtropical settings and the dynamics of colonization on limestone. [Copyright &y& Elsevier]

The widespread use of antibiotics has increased their presence in wastewater, largely due to inadequate removal by conventional treatment methods. This highlights a critical need for effective degradation strategies to mitigate environmental and public health risks. This study reports the photocatalytic degradation of amoxicillin (AMX) using calcium zinc hydroxide dihydrate [CaZn 2 (OH) 6 ·2H 2 O] (CZ) and zinc oxide (ZnO) nanoparticles (NPs) synthesized by different routes. X-ray diffraction results confirmed the formation of CZ NPs with an 81–95% crystalline phase, while ZnO NPs present a single crystalline phase. The photolysis of AMX under UV-A light (365 nm) was strongly pH-dependent, with degradation rates of 34.7, 5.7, and 4.2% observed at pH 3, 5, and 13, respectively. Maximum adsorption occurred at pH 3, with ZnO achieving 63–83.2% AMX removal and 23.5–47.1% in the case of CZ. The highest overall AMX removal was observed at pH 3, where adsorption dominated the photocatalytic process for both CZ and ZnO. At pH 5 and 13, degradation was primarily driven by photocatalysis in CZ materials, particularly CZ-HT and CZ-SG, while adsorption remained predominant in ZnO. Proton nuclear magnetic resonance analysis indicates benzene ring cleavage in AMX photodegraded by CZ materials. Furthermore, the residues of photodegraded AMX by CZ materials lost antimicrobial activity against Gram-positive and Gram-negative bacteria. Additionally, the reuse of NPs over four cycles maintained consistent degradation performance, highlighting their potential for repeated applications. The comparative analysis of CZ and ZnO NPs superior photocatalytic efficiency of CZ in degrading AMX. This efficiency, along with its potential for repeated use, establish CZ as a promising material for environmental applications aimed at reducing antibiotic contamination and the associated risks of resistance development. [Display omitted] • CaZn 2 (OH) 6 ·2H 2 O (CZ) achieves high photocatalytic degradation of amoxicillin. • ZnO NPs show no photocatalytic activity, although it adsorbs amoxicillin. • Complete loss of antimicrobial activity in the amoxicillin residuals was confirmed. • CZ and ZnO maintain photocatalytic or adsorption activity over multiple reuse cycles. • The removal of amoxicillin were confirmed by 1H RMN spectra. [ABSTRACT FROM AUTHOR]