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Background: Secondary metabolites from the group of isoprenoid compounds are widely distributed in mangrove plants. Polyisoprenoids (dolichol and polyprenol) are known to have benefits as anticancer agents. The present study was conducted to determine the cytotoxic potential of polyisoprenoids in leaves from seventeen selected mangrove species against colon cancer (WiDr) cells. Methods: Cytotoxic activity was evaluated by MTT assay in vitro using WiDr human colon cancer cells and 3T3 fibroblasts from Swiss albino mouse embryo tissue as controls. Mechanisms of action were approached by assessing apoptosis and the cell cycle using flow cytometry and fluorescence microscopy with annexin V-FITC, as well as expression of Bcl-2 and cyclin D1 by immunocytochemistry. Results: Polyisoprenoids from N. fruticans leaves demonstrated the highest anticancer activity, with an IC 50 of 180.2 µg/mL, as compared to 397.7 µg/mL against 3T3 normal cells. Significant decrease in the expression of Bcl-2 and cyclin D1 was also noted, facilitating apoptosis and arrest of the cell cycle in the G0-G1 phase in WiDr cells. The present study showed for the first time that polyisoprenoids from N. fruticans exhibit concrete anticancer activity in vitro, decreasing cell proliferation and inducing apoptosis in colon cancer cells. Conclusions: Polyisoprenoids isolated from N. fruticans leaves may have promise as a source of anticancer agents.

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The sustainability, performance, and cost of production in the plywood industry depend on wood adhesives and the hot-pressing process. In this study, a cold-setting plywood adhesive was developed based on polyvinyl alcohol (PVOH), high-purity lignin, and hexamine. The influence of lignin content (10%, 15%, and 20%) and cold-pressing time (3, 6, 12, and 24 h) on cohesion, adhesion, and formaldehyde emission of plywood were investigated through physical, chemical, thermal, and mechanical analyses. The increased lignin addition level lowered the solids content, which resulted in reduced average viscosity of the adhesive. As a result, the cohesion strength of the adhesive formulation with 10% lignin addition was greater than those of 15% and 20% lignin content. Markedly, the adhesive formulation containing a 15% lignin addition level exhibited superior thermo-mechanical properties than the blends with 10% and 20% lignin content. This study showed that 10% and 15% lignin content in the adhesive resulted in better cohesion strength than that with 20% lignin content. However, statistical analysis revealed that the addition of 20% lignin in the adhesive and using a cold-pressing time of 24 h could produce plywood that was comparable to the control polyurethane resins, i.e., dry tensile shear strength (TSS) value of 0.95 MPa, modulus of rupture (MOR) ranging from 35.8 MPa, modulus of elasticity (MOE) values varying from 3980 MPa, and close-to-zero formaldehyde emission (FE) of 0.1 mg/L, which meets the strictest emission standards. This study demonstrated the feasibility of fabricating eco-friendly plywood bonded with PVOH–lignin–hexamine-based adhesive using cold pressing as an alternative to conventional plywood.

Cellulose Nanofibrils (CNF) was successfully obtained by TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation with the addition of different oxidant namely NaClO (Sodium Hypochlorite) i.e. 3, 4, 7, 10 and 15 mL followed by ultra-sonication treatment. Size distribution of nanocellulose was observed using particle size analyzer, while surface charged was measured using zeta potentiometer. At different level of oxidant, CNF obtained different charged with different size distribution. As the amount of oxidant increased, the size distribution of CNF increased which correlated to the higher CNF yield, however it decreased at maximum oxidant addition. Although, in general the yield for nanocellulose was very low. With zeta potential value about -48 mV, it showed very stable suspension in water for more than 8 months observation. An optimum oxidant level promoted thinner and longer CNF which further beneficial for better entanglement in the hydrogel formation application.