Background: Dendroctonus rhizophagus is a bark beetle of great forest importance, due to its aggressive root colonization of seedlings and young pine trees. To successfully complete their life cycle, these insects and associated microorganisms must overcome the trees’ complex defense system. However, little is known about the enzymes and metabolic pathways involved in xenobiotic detoxification by microbial symbionts of bark beetles. We investigated the genomic potential for detoxification in bacteria Acinetobacter , Pseudomonas , Rahnella and Serratia , as well as the yeasts Candida [ Ogataea clade], Danielia , Cyberlindnera and Zygoascus , dominant members of the gut core microbiome of D . rhizophagus , through assembly, annotation, and comparison of their genomes. Results: Genome analysis identified 1,293 genes in bacteria and yeasts related to 22 KO xenobiotic-degradation pathways. These pathways include those for aromatic compounds (benzoate, ferulate, vanillin), monoterpenes (pinene, camphor, geraniol, limonene) and diterpenes ( dit genes). Additionally, the genomes contained genes encoding members of the following enzymatic families: cytochrome P450, carboxylesterases, laccases, aldehyde and alcohol dehydrogenases, flavin binding-monooxygenases, intradiol and extradiol dioxygenases, glutathione S-transferases, and multidrug resistance transporters (ABC, MFS, MATE, and RND) implicated in the detoxification process. Conclusions: Integration of these genes across the phases of xenobiotic detoxification reveals potential functional complementarity between bacteria and yeasts, suggesting that members of the gut microbiota of D. rhizophagus may enhance the beetle’s fitness by facilitating the metabolism and tolerance to the tree´s toxic compounds.

Hypertension is a prevalent disorder that results in millions of deaths worldwide. In this regard, timely diagnosis and effective treatment are paramount for maintaining optimal blood pressure levels in the early stages of the disease. The objective of the present study was to synthesize and assess the effect of peptides derived from chia seeds that had undergone fermentation with Lacticaseibacillus paracasei strain 2501 (hereinafter referred to as LPDP, i.e., L. paracasei-derived products from this fermentation) on the angiotensin-converting enzyme (ACE) and the spontaneously hypertensive rat model (SHR). LPDP exhibited competitive inhibition, as evidenced by the identification of seven peptides in the <1 kDa fraction by HPLC-QToF-MS. The LPDP exhibited an IC₅₀ of 11.1 μg/mL on ACE. The oral administration of 50 mg/kg body weight (BW) to SHR over a 14-day period resulted in a significant reduction in systolic pressure from 152 to 87 mmHg, accompanied by a substantial decrease in diastolic pressure from 117 to 74 mmHg. It is noteworthy that doses of 500 mg/kg BW led to a significant reduction in systolic pressure, from 154 to 68 mmHg and diastolic pressure, from 117 to 42 mmHg under identical experimental conditions. The hematological profiling of the assayed animals revealed that LPDP has no adverse effects at the cellular or biochemical level. These findings indicate the anti-hypertensive properties of LPDP and its possible application in the treatment of blood pressure.

Orchid root-associated fungal endophytes (ORAFEs) represent an important component of fungal biodiversity with potential applications in orchid conservation and sustainable production. ORAFEs were isolated from the roots of four orchid species in Veracruz, Mexico: Gongora galeata, Maxillaria densa, Maxillaria tenuifolia, and Maxillaria variabilis to investigate their diversity and plant-growth-promoting (PGP) properties. Taxonomic identification relied on morphological and molecular phylogenetic analyses using ITS, TEF1-α, β-tubulin (TUB2), and actin (ACT). Fifty-six isolates were grouped into 20 morphotypes representing 15 genera, including Aspergillus, Biscogniauxia, Chaetomium, Colletotrichum, Thelonectria, Diaporthe, Fusarium, Geotrichum, Hypoxylon, Lasiodiplodia, Mucor, Periconia, Pestalotiopsis, Trichoderma, Xylaria, and two isolates that may represent undescribed taxa requiring further polyphasic taxonomic investigation. Functional experiments indicated a wide range of PGP activities: ten strains solubilized phosphate, eight produced siderophores, twelve synthesized indole-3-acetic acid, fourteen produced pectinases, six fungi exhibited antibacterial activity against Bacillus subtilis, and five inhibited Staphylococcus aureus. Furthermore, Trichoderma atroviride TR1-T2 and Xylaria multiplex XY1-D42 showed antagonistic activity against Phytopythium vexans, characterized by a contact-dependent displacement effect. Five strains were chosen for further research as orchid bioinoculants based on their PGP and antagonistic traits: Chaetomium cochliodes CH1-V10, Mucor pseudolusitanicus MU2-T6, Thelonectria veuillotiana TH1-T3, Trichoderma atroviride TR1-T2, and Xylaria multiplex XY1-D42. These endophytes have the potential to improve in vitro propagation and facilitate ex vitro acclimatization of orchids, highlighting their importance in sustainable orchid production.