The rise of anthropogenic activities has resulted in the increasing release of various contaminants into the environment, jeopardizing fragile ecosystems in the process. Heavy metals are one of the major pollutants that contribute to the escalating problem of environmental pollution, being primarily introduced in sensitive ecological habitats through industrial effluents, wastewater, as well as sewage of various industries. Where heavy metals like zinc, copper, manganese, and nickel serve key roles in regulating different biological processes in living systems, many heavy metals can be toxic even at low concentrations, such as mercury, arsenic, cadmium, chromium, and lead, and can accumulate in intricate food chains resulting in health concerns. Over the years, many physical and chemical methods of heavy metal removal have essentially been investigated, but their disadvantages like the generation of chemical waste, complex downstream processing, and the uneconomical cost of both methods, have rendered them inefficient,. Since then, microbial bioremediation, particularly the use of bacteria, has gained attention due to the feasibility and efficiency of using them in removing heavy metals from contaminated environments. Bacteria have several methods of processing heavy metals through general resistance mechanisms, biosorption, adsorption, and efflux mechanisms. Bacillus spp. are model Gram-positive bacteria that have been studied extensively for their biosorption abilities and molecular mechanisms that enable their survival as well as their ability to remove and detoxify heavy metals. This review aims to highlight the molecular methods of Bacillus spp. in removing various heavy metals ions from contaminated environments.

Red Seaweed “Rhodophyta” are an important group of macroalgae that include approximately 7000 species. They are a rich source of structurally diverse bioactive constituents, including protein, sulfated polysaccharides, pigments, polyunsaturated fatty acids, vitamins, minerals, and phenolic compounds with nutritional, medical, and industrial importance. Polysaccharides are the main components in the cell wall of red algae and represent about 40–50% of the dry weight, which are extensively utilized in industry and pharmaceutical compounds, due to their thickening and gelling properties. The hydrocolloids galactans carrageenans and agars are the main red seaweed cell wall polysaccharides, which had broad-spectrum therapeutic characters. Generally, the chemical contents of seaweed are different according to the algal species, growth stage, environment, and external conditions, e.g., the temperature of the water, light intensity, nutrient concentrations in the ecosystem. Economically, they can be recommended as a substitute source for natural ingredients that contribute to a broad range of bioactivities like cancer therapy, anti-inflammatory agents, and acetylcholinesterase inhibitory. This review touches on the main points of the pharmaceutical applications of red seaweed, as well as the exploitation of their specific compounds and secondary metabolites with vital roles.

The increasing emergence of bacterial resistance is a challenge for the research community, thus novel antibacterial agents should be developed. Metal nanoparticles are promising antibacterial agents and could solve the problem of antibiotic resistance. Herein, we used Gardenia thailandica methanol extract (GTME) to biogenically synthesise zinc oxide nanoparticles (ZnO-NPs). The characterisation of ZnO-NPs was performed by UV spectroscopy, FTIR, scanning and transmission electron microscopes, dynamic light scattering, and X-ray diffraction. The antibacterial activity of ZnO-NPs was studied both in vitro and in vivo against Pseudomonas aeruginosa clinical isolates. Its minimum inhibitory concentration values ranged from 2 to 64 µg/mL, and it significantly decreased the membrane integrity and resulted in a significant increase in the inner and outer membrane permeability. Also, the ZnO-NPs treated cells possessed a distorted and deformed shape when examined by scanning electron microscope. The in vivo study (biochemical parameters and histological investigation) was conducted and it revealed a protective effect of ZnO-NPs against the deleterious influences of P. aeruginosa bacteria on lung, liver, and kidney tissues. LC-ESI-MS/MS revealed a phytochemical tentative identification of 57 compounds for the first time. We propose that GTME is a useful source for ZnO-NPs which has a promising antibacterial activity. Graphical Abstract

Solanum elaeagnifolium is among the invasive plants of Morocco; studies on its chemical composition and biological activities are few in number in Morocco. S. elaeagnifolium has shown molluscicidal and nematicidal and cancer-inhibitory effects, anti-inflammatory, analgesic activity, and antibacterial activity. The objective of this research is to improve this plant and assess its antibacterial and antioxidant properties as well as its total polyphenolic content (TPC) and total flavonoid content (TFC). The Folin-Ciocalteu method and the aluminium-trichloride method were used to determine TPC and TFC in hydro-ethanolic (HEE) and hydro-acetonic (HAE) leaf extract. Three assays were performed to determine the antioxidant activity: the DPPH test (radical 2,2’-diphenyl-1-picrylhydrazyl), the FRAP test (Ferric Reducing Antioxidant Power), and the TAC test. Disk diffusion and microdilution were used to test antibacterial activity against four pathogenic bacteria and Candida albicans. The hydro-ethanolic extract 2.54 ± 0.4 mg EAG/g has a greater polyphenol concentration than the hydro-acetonic extract 1.58 ± 0.03 mg EAG/g. Although the flavonoid content of the hydro-acetonic extract (0.067 ± 0.001 mg EQ/g) is larger than that of the hydro-ethanolic extract (0.012 ± 0.001 mg EQ/g), the flavonoid content of the hydro-ethanolic extract (0.012 ± 0.001 mg EQ/g). The DPPH values were IC-50 = 0.081 ± 0.004 mg/mL for hydro-ethanoic extract and 0.198 ± 0.019 mg/mL for hydro-acetonic extract, both extracts superior to BHT (0.122 ± 0.021 g/mL). While the FRAP assay showed a low iron-reducing power values for both extracts compared to BHT), the overall antioxidant activity of the two extracts was found to be considerable. The overall antioxidant activity of the hydro-ethanolic extract was 8.95 ± 0.42 mg EAA/g, whereas the total antioxidant activity of the hydro-acetonic extract was 6.44 ± 0.61 mg EAA/g. In comparison with the antibiotic Erythromycin, HAE and HEE from S. elaeagnifolium leaves demonstrated significant antibacterial action. HAE had the best inhibitory efficacy against Bacillus subtilis DSM 6333, with an inhibition diameter of 10.5 ± 0.50 mm and a MIC of 7.5 ± 0.00 mg/mL, as well as against Proteus mirabilis ATCC 29906, with an inhibitory diameter of 8.25 ± 0.75 mm and a MIC of 15 ± 0.00 mg/mL.

Epigallocatechin-3-gallate (EGCG) was isolated from Cycas thouarsii leaves for the first time and encapsulated in aqueous core poly(lactide-co-glycolide) (PLGA) nanocapsules (NCs). This work investigates antimicrobial activity and in vivo reno-protective effects of EGCG-PLGA NCs in cisplatin-induced nephrotoxicity. A double emulsion solvent evaporation process was adopted to prepare PLGA NCs loaded with EGCG. Particle size, polydispersity index (PDI), zeta potential, percent entrapment efficiency (%EE), structural morphology, and in vitro release platform were all studied in vitro. The optimum formula (F2) with particle size (61.37 ± 5.90 nm), PDI (0.125 ± 0.027), zeta potential (–11.83 ± 3.22 mV), %EE (85.79 ± 5.89%w/w), initial burst (36.85 ± 4.79), and percent cumulative release (87.79 ± 9.84) was selected for further in vitro/in vivo studies. F2 exhibited an enhanced antimicrobial activity against uropathogens as it had lower minimum inhibitory concentration (MIC) values and a more significant impact on bacterial growth than free EGCG. Forty male adult mice were randomly allocated into five groups: control vehicle, untreated methotrexate, MTX groups treated with a daily oral dose of free EGCG, placebo PLGA NCs, and EGCG PLGA NCs (F2) for 10 days. Results showed that EGCG PLGA NCs (F2) exerted promising renoprotective effects compared to free EGCG. EGCG PLGA NCs group induced a significant decrease in kidney index, serum creatinine, kidney injury molecule-1 (KIM-1), NGAL serum levels, and pronounced inhibition of NLPR-3/caspase-1/IL/1β inflammasome pathway. It also significantly ameliorated oxidative stress and decreased NFκB, Bax expression levels. Aqueous core PLGA NCs are a promising formulation strategy that provides high polymeric protection and sustained release pattern for hydrophilic therapeutic agents.

Lung diseases such as asthma, chronic obstructive pulmonary diseases, and pneumonia are causing many global health problems. The COVID-19 pandemic has directed the scientific community’s attention toward performing more research to explore novel therapeutic drugs for pulmonary diseases. Herein, gas chromatography coupled with mass spectrometry tentatively identified 44 compounds in frankincense ethanol extract (FEE). We investigated the antibacterial and antibiofilm effects of FEE against Pseudomonas aeruginosa bacteria, isolated from patients with respiratory infections. In addition, its in vitro immunomodulatory activity was explored by the detection of the gene expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide synthase (iNOS), cycloxygenase-2 (COX-2), and nuclear factor kappa-B (NF-κB) in lipopolysaccharide (LPS)-induced peripheral blood mononuclear cells (PBMC). In addition, its anticancer activity against the A549 lung cancer cell line and human skin fibroblast (HSF) normal cell line was studied. Moreover, the in vivo lung protective potential of FEE was explored histologically and immunohistochemically in mice using a benzo(a)pyrene induced lung damage model. FEE exhibited antibacterial and antibiofilm activities besides the significant inhibition of gene expression of TNFα, IL-6, and NF-κB. FEE also exerted a cytotoxic effect against A549 cell line. Histological and immunohistochemical investigations with morphometric analysis of the mean area percentage and color intensity of positive TNF-α, COX-2, and NF-κB and Bcl-2 reactions revealed the lung protective activity of FEE. This study outlined the promising therapeutic activity of oleoresin obtained from B. dalzielii in the treatment of different pulmonary diseases.