Due to the indiscriminate use of antimicrobial drugs in the treatment of infectious diseases, human pathogenic bacteria have developed resistance to many commercially available antibiotics. Medicinal plants such as Convolvulus arvensis represent a renewable resource for the development of alternative therapeutic agents. This study aimed to evaluate the antibacterial activity of silver nanoparticles (AgNPs) biosynthesized from C. arvensis against two clinical antibiotic-resistant bacterial isolates. The pathogenic isolates were identified as Staphylococcus aureus MRSA and Escherichia coli ESBL using 16S rRNA gene sequencing. Silver nanoparticles were synthesized via a green synthesis approach, and their physicochemical properties were characterized using UV–Vis spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, zeta potential, and dynamic light scattering (DLS). The synthesized C. arvensis–AgNPs exhibited a surface plasmon resonance peak at 475 nm and predominantly spherical morphology with particle sizes ranging from 102.34 to 210.82 nm. FTIR analysis indicated the presence of O–H, C–O, C–N, C–H, and amide functional groups. The nanoparticles showed a zeta potential of −18.9 mV and an average hydrodynamic diameter of 63 nm. The antibacterial activity of the biosynthesized AgNPs was evaluated against methicillin-resistant S. aureus (MRSA and ATCC 29213) and E. coli (ESBL and ATCC 25922) using agar diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays. Inhibition zones ranged from 10 to 13 mm, with MIC and MBC values of 12.5–25 µg/mL and 25–50 µg/mL, respectively. In addition, the nanoparticles exhibited antioxidant activity (DPPH assay, IC₅₀ = 0.71 mg/mL) and anti-inflammatory effects as determined by protein denaturation inhibition. No cytotoxic effects were observed in the MCF-7 cell line at the MIC level. These findings suggest that C. arvensis–AgNPs have potential as natural antimicrobial, antioxidant, and anti-inflammatory agents.

Avicennia marina dominates mangrove communities along the hypersaline Arabian Gulf, yet links among local habitat conditions, secondary metabolite profiles

Mangrove ecosystems provide essential ecological services, including coastal protection, carbon sequestration, and biodiversity conservation, yet they are increasingly threatened by emerging plant diseases. During a disease survey conducted in February 2024 in the Sihat mangrove ecosystem (Eastern Saudi Arabia), Avicennia marina leaves exhibiting necrotic leaf spot symptoms were collected and examined. Based on morphological characteristics and ITS rDNA sequence analysis, the causal agent was identified as Fusarium equiseti, representing the first report of this pathogen causing leaf spot disease in Saudi mangroves. Pathogenicity was confirmed by fulfilling Koch’s postulates on detached healthy leaves. To explore environmentally sustainable disease management strategies, a soil-derived bacterial strain (Bac4) was evaluated for antifungal activity. Molecular identification using 16S rRNA gene sequencing revealed 100% similarity with Pseudomonas aeruginosa. In vitro assays demonstrated strong antagonistic activity of Bac4 against F. equiseti. The cell-free supernatant (CFS) significantly inhibited mycelial growth, biomass production, and spore germination in a dose-dependent manner, achieving up to 65.74% radial growth inhibition at a 50% CFS concentration. Microscopic observations revealed severe hyphal deformation, swelling, and cytoplasmic disintegration in treated fungi. Volatile organic compounds (VOCs) emitted by Bac4 also suppressed fungal growth and pigmentation, and this effect was partially reversed by activated charcoal, confirming VOC-mediated antifungal activity. Gas chromatography–mass spectrometry (GC–MS) analysis of the CFS identified several bioactive metabolites, including alcohols, diketopiperazines, and actinomycin derivatives. In vivo assays using detached mangrove leaves demonstrated a disease control efficiency of 70.33%, exceeding that of the commercial fungicide Hymexazol. Overall, the results indicate that P. aeruginosa Bac4 produces both diffusible and volatile antifungal metabolites and represents a promising biocontrol agent for the sustainable management of leaf spot disease in mangrove ecosystems.

Mangrove ecosystems are among the most productive and ecologically significant coastal habitats, providing essential services such as carbon sequestration, shoreline stabilization, and biodiversity support under extreme saline and anoxic conditions. Increasing evidence highlights the pivotal role of endophytic microorganisms residing asymptomatically within mangrove plant tissues in enhancing host adaptation and ecosystem resilience. However, global patterns of their diversity, functional traits, and biotechnological potential remain fragmented across studies. This review provides a comprehensive synthesis of peer-reviewed literature published between 2000 and 2025, retrieved from Web of Science, Scopus, and PubMed, using a structured and reproducible search strategy. A total of 187 studies were analyzed, yielding 152 identified endophytic species. Fungi accounted for approximately 58% of reported taxa, followed by bacteria (39%) and archaea (3%), with Ascomycota and Proteobacteria emerging as dominant phyla across host species and geographic regions. Functionally, mangrove endophytes contribute to nutrient acquisition, stress tolerance, and the production of diverse bioactive compounds with antioxidant, antibacterial, and enzymatic activities. Despite these promising attributes, significant discrepancies between culture dependent and metagenomic approaches influence diversity estimates and functional interpretations, highlighting the need for standardized methodologies and integrative multi-omics frameworks. While endophytes demonstrate clear benefits at the plant level, their large-scale ecological contributions and industrial applicability remain insufficiently validated. This review bridges ecological and biotechnological perspectives by identifying key research gaps, methodological limitations, and priority directions for future studies, ultimately supporting the development of sustainable applications derived from mangrove-associated microbial resources.

Mangrove ecosystems are keystone coastal habitats that support high levels of biodiversity and provide essential ecosystem services, including carbon sequestration, shoreline stabilization, nutrient cycling, and fisheries support. Despite their ecological resilience, mangroves are increasingly threatened by the combined effects of abiotic and biotic stressors. Coastal development, pollution, hydrological alteration, sea-level rise, and climate extremes interact with biological pressures such as insect herbivory, invasive species, and pathogenic microorganisms, leading to habitat degradation and loss of ecosystem functionality. This review synthesizes current global evidence on the drivers of mangrove biodiversity decline, emphasizing the mechanistic interactions between abiotic and biotic factors. It uniquely integrates ecological, physiological, and conservation perspectives to provide a comprehensive framework for understanding mangrove vulnerability and resilience. We further highlight evidence-based conservation and restoration strategies required to sustain mangrove ecosystem services under accelerating environmental change. This review provides an integrated framework linking environmental stressors with ecological responses, offering insights to support effective conservation and sustainable management of mangrove ecosystems.