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Developing biosynthesis of silver nanoparticles (Ag-NPs) using plant extract is an environmentally friendly method to reduce the use of harmful chemical substances. The green synthesis of Ag-NPs by Lawsonia inermis extract and its cellular toxicity and the antimicrobial effect was studied. The physical and chemical properties of synthesised Ag-NPs were investigated using UV-visible spectroscopy, infrared spectroscopy, X-ray diffraction (XRD), scanning, and transmission electron microscopy. The average size of Ag-NPs was 40 nm. The XRD result shows peaks at 2θ = 38.07°, 44.26°, 64.43°, and 77.35°are related to the FCC structure of Ag-NPs. Cytotoxicity of synthesised nanoparticles was evaluated by MTT toxicity test on breast cancer MCF7 cell line. Observations showed that the effect of cytotoxicity of nanoparticles on the studied cell line depended on concentration and time. The obtained IC 50 was considered for cells at a dose of 250 μg/ml. Growth and survival rates decreased exponentially with the dose. Antimicrobial properties of Ag-NPs synthesised with extract were investigated against Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus to calculate the minimum inhibitory concentration and the minimum bactericidal concentration of (MBC). The results showed that the synthesised Ag-NPs and the plant extract have antimicrobial properties. The lowest concentration of Ag-NPs that can inhibit the growth of bacterial strains was 25 μg/ml.

Nowadays, the logarithmic production of existing well-known food materials is unable to keep up with the demand caused by the exponential growth of the human population in terms of the equality of access to food materials. Famous local food materials with treasury properties such as mangrove fruits are an excellent source to be listed as emerging food candidates with ethnomedicinal properties. Thus, this study reviews the nutrition content of several edible mangrove fruits and the innovation to improve the fruit into a highly economic food product. Within the mangrove fruit, the levels of primary metabolites such as carbohydrates, protein, and fat are acceptable for daily intake. The mangrove fruits, seeds, and endophytic fungi are rich in phenolic compounds, limonoids, and their derivatives as the compounds present a multitude of bioactivities such as antimicrobial, anticancer, and antioxidant. In the intermediary process, the flour of mangrove fruit stands as a supplementation for the existing flour with antidiabetic or antioxidant properties. The mangrove fruit is successfully transformed into many processed food products. However, limited fruits from species such as Bruguiera gymnorrhiza, Rhizophora mucronata, Sonneratia caseolaris, and Avicennia marina are commonly upgraded into traditional food, though many more species demonstrate ethnomedicinal properties. In the Middle East, A. marina is the dominant species, and the study of the phytochemicals and fruit development is limited. Therefore, studies on the development of mangrove fruits to functional for other mangrove species are demanding. The locally accepted mangrove fruit is coveted as an alternate food material to support the sustainable development goal of eliminating world hunger in sustainable ways.

The broad application of metal nanoparticles in different fields encourages scientists to find alternatives to conventional synthesis methods to reduce negative environmental impacts. Herein, we described a safe method for preparing silver nanoparticles (J-AgNPs) using Jatropha integerrima leaves extract as a reducing agent and further characterize its physiochemical and pharmacological properties to identify its therapeutic potential as a cytotoxic and antimicrobial agent. The biogenic synthesized J-AgNPs were physiochemically characterized by ultraviolet-visible spectroscopy, dynamic light scattering (DLS), transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy. HPLC-DAD, followed by LC/MS and the Fourier-transform infrared spectroscopy (FTIR), was applied to detect the biomolecules of J. integerrima involved in the fabrication of NPs. Furthermore, J-AgNPs and the ampicillin-nanocomposite conjugate were investigated for their potential antibacterial effects against four clinical isolates. Finally, cytotoxic effects were also investigated against cancer and normal cell lines, and their mechanism was assessed using TEM analysis and confocal laser scanning microscopy (LSM). Ag ions were reduced to spherical J-AgNPs, with a zeta potential of −34.7 mV as well as an average size of 91.2 and 22.8 nm as detected by DLS and TEM, respectively. HPLC GC/MC analysis identified five biomolecules, and FTIR suggested the presence of proteins besides polyphenolic molecules; together, these molecules could be responsible for the reduction and capping processes during NP formation. Additionally, J-AgNPs displayed a strong antibacterial effect, although the ampicillin conjugated form had a very weak antibacterial effect. Furthermore, the NPs caused a reduction in cell viability of all the treated cells by initiating ultrastructural changes and apoptosis, as identified by TEM and LSM analysis. Therefore, J-AgNPs can be formed using the leaf extract from the J. integerrima plant. Furthermore, J-AgNPs may serve as a candidate for further biochemical and pharmacological testing to identify its therapeutic value.

We studied mycotoxigenic fungi contaminating stored wheat grain, measured the toxins they secreted, and assessed their harmfulness. We focused on one common genus Alternaria, and chose 19 isolates representing A. compacta to study how different strains differed in their mycotoxin secretion and toxicity. Toxicity was assessed in a bioassay with a model bacteria Bacillus subtilis. All 19 A. compacta strains secreted toxins. Both the mycotoxin pattern and the fungal toxicity differed between the A. compacta stains. It seemed that some other toxins than alternariols or altenue acted as the main virulence factors of A. compacta against B. subtilis. We suggest that the most commonly studied mycotoxins do not necessarily indicate the toxicity of the fungi. The high variation in the amounts and toxins that different Alternaria species and strains secrete pose a challenge to the food supply chain.

In the agricultural domain, chemical pesticides are repetitively and harshly used to kill harmful pests, but they often pose a serious threat to microbial diversity, soil fertility and agricultural output.

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A winter bloom event of Trichodesmium erythraeum was monitored for the first time in the southeastern coastal parts of Bangladesh along the Bay of Bengal. This study presents the brownish to light pinkish bloom that appeared in mid-winter and disappeared abruptly during spring. Heavy blooms of T. erythraeum revealed the highest concentration of 91.47 ± 52.94 × 103 colonies/L in the Bakkhali River Estuary, and 66.93 ± 12.95 × 103 colonies/L in the Maheshkhali Channel of the Bay of Bengal. Three distinct morphological shapes, namely puffs, tufts and asymmetrical colonies, were depicted as major types. Several environmental factors, such as water temperature, salinity, pH, dissolved oxygen, NO3–N and PO4–P, were analyzed to determine their relationship with the occurrence, abundance and bloom formation of T. erythraeum. The abundance of the species showed a positive correlation with salinity and pH while exhibiting a negative correlation with temperature and DO. A cluster analysis revealed a clear indication of T. erythraeum bloom during winter. Thus, the prevalence of the highest density of the bloom in the present study area strongly suggests increased monitoring and research efforts in order to effectively manage or impede harmful algal blooms.