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Abstract Background A study carried out by World Health Organization revealed that around 80% of individuals globally depends on herbal forms of medication with 40% of pharmaceutical products being sourced from medicinal plants. The study objective was to evaluate the phytochemicals composition, in vitro antimicrobial and antioxidant properties of the leaves of Terminalia catappa L. aqueous and methanolic extracts. Methods Antimicrobial activity was analyzed by disk diffusion, the minimum inhibitory concentration in-vitro assays with ciprofloxacin as the standard for antibacterial assay while nystatin for antifungal assay. Ferric reducing antioxidant power and 2,2-diphenyl-1-picryl-hydrazyl-hydrate assays were used for the evaluation of antioxidant properties of the crude extracts while the groups responsible for this activity identified using Fourier transform infrared spectrophotometer. Results The study found that the leaves of Terminalia catappa contained alkaloids, tannins, steroids, cardiac glycosides, flavonoids, phenols, saponins, and coumarins, but terpenoids were absent. Presence of functional groups associated with this class of compounds such as OH vibrational frequencies were observed in IR spectrum of the crude extracts. Methanolic extract from Terminalia catappa exhibited greater antibacterial properties against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus, whereas aqueous extract displayed greater antibacterial activity against Bacillus subtilis for all concentrations tested. The amount of the sample that scavenged 50 percent of DPPH (IC50) was found to be 8.723, 13.42 and 13.04 µg/mL for L-ascorbic acid, Terminalia catappa L. methanolic and aqueous extracts respectively. The antimicrobial and antioxidant activities varied with the extract concentration and solvent used in extractions. Conclusion Terminalia catappa L. leaves are prospective for use as a source of therapeutic agents that could lead to the advancement of new antimicrobial and antioxidant products.

Abstract Recent findings of microplastics in marine food such as fish, crabs and shrimps necessitate the need to develop biodegradable packaging materials. This study reports on the development of a biodegradable packing material from cellulose nanofibril-polyvinyl alcohol nanocomposite embedded with silver nanoparticles. Microcrystalline cellulose was isolated from sugarcane bagasse via the kraft process followed by conversion of cellulose I to cellulose II using NaOH/urea/water solution. The nanofibrils were then isolated using (2,2,6,6-Tetramethylpiperidin-1-yl) oxyl (TEMPO) and used as a reinforcing element in polyvinyl alcohol composite prepared through solvent casting. The tensile strength, water solubility, optical properties, water vapor permeability and wettability of the prepared films were then evaluated. The antimicrobial potency of the films was evaluated using the disc diffusion antimicrobial assay against selected microorganisms.

This work aimed to extract and characterize microcrystalline cellulose from coir fibers. Extraction was achieved in a two-step process in which the coir fibers were treated with sodium hydroxide for 3 h at 100°C followed by bleaching with peracetic acid to remove residual lignin and hemicellulose. The microcrystalline cellulose powder characteristics such as the bulk density, tapped density, angle of repose and swelling ratio were found to be 0.08 ± 0.00 g/cm3, 0.12 ± 0.0 g/cm3, 38° and 8.15 ± 0.14 g/g, respectively. Fourier transform infrared spectroscopy exhibited characteristic microcrystalline cellulose peaks. The degree of crystallinity microcrystalline cellulose was found to be 39.5% as determined by X-ray diffraction analysis. The Differential scanning calorimetry and Thermogravimetric analysis revealed that the glass transition and onset of degradation temperature for microcrystalline cellulose were 206°C and 196°C, respectively. From the results, it was concluded that the coir fibers could be a good source of microcrystalline cellulose for applications in the binder, pharmaceutical, and paper making industries due to its powder properties, good swelling, and compressibility.