Effect of Hydrothermal Carbonization Parameters and Performance of Carbon Dioxide Adsorption on Pineapple Peel Waste Biochar

Low-cost biochar adsorbents were prepared from pineapple peel waste (PPW) via hydrothermal carbonization (HTC) for CO2 capture. The effects of hydrothermal carbonization temperature, retention time, and heating rate were studied. The hydrochar samples were further carbonized to produce pineapple peel biochar adsorbents. The effects of CO2 concentration in the feed, adsorption temperature, and feed flow rate on adsorption capacity were investigated in a fixed-bed column adsorption system. The experimental data were analyzed using pseudo-first-order and pseudo-second-order kinetics, and the Avrami equation. The CO2 adsorption capacity of this system was improved with increasing CO2 feed concentration and decreased with rising temperature and feed flow rate. The Avrami kinetics model was best fitted to the experimental data. The CO2 adsorption performance of PPW biochar (PPW-BC) in a fixed-bed column was successfully predicted by the Thomas and Yoon-Nelson models. The prepared PPW-BC adsorbents could be a viable option for CO2 capture because they were synthesized from a low-cost biomass source and are environmentally benign.This research is funded by the Research University Incentive Grant (PJKIMIA/1001/8014064) provided by the Universiti Sains Malaysia. The first author would also like to acknowledge the financial support by the Ministry of Higher Education (MOHE), Malaysia and Universiti Malaysia Perlis

Evaluation of Possible Antioxidant, Anti-Hyperglycaemic, Anti-Alzheimer and Anti-Inflammatory Effects of <i>Teucrium polium</i> Aerial Parts (Lamiaceae)

Teucrium polium L. is commonly used in folk medicine to treat hypertension and diabetes and to heal wounds. The present work aimed to evaluate the different biological activities of T. polium hydroalcoholic extract, its total phenol and flavonoid content, and its mineral elements. Results showed that T. polium extract showed significant antioxidant potential in 2-diphenyl-1-picrylhydrazyl (DPPH) assay with IC50 equal to 8.68 μg/mL but with moderate activity in galvinoxyl assay with IC50 of 21.82 μg/mL and mild activity in the β-carotene assay. It also showed a pronounced anti-hyperglycemic activity using α-amylase inhibitory assay (IC50 = 111.68 µg/mL) and exceeds that of acarbose. T. polium showed excellent activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values of 28.69 and 4.93 μg/mL, respectively, postulating its promising anti-Alzheimer potential. The plant extract exhibited a strong anti-inflammatory effect with Bovine Serum Albumin (BSA) denaturation inhibitory potential estimated by 97.53% at 2 mg/mL, which was further confirmed by the in vivo carrageen-induced edema model. The extract revealed its richness in flavonoids and phenols, evidenced by its polyphenols content (36.35 ± 0.294 μg GAE/mg) and flavonoids (24.30 ± 0.44 μg QE/mg). It is rich in minerals necessary for human health, such as calcium, potassium, iron, sodium, magnesium, manganese and zinc. Molecular docking performed for previously identified compounds on human α-amylase, 5-lipoxygenase (5-LOX) and acetylcholine esterase confirmed the results. Thus, it can be concluded that T. polium can be a good candidate for alleviating many health-debilitating problems and can be highly beneficial in the pharmaceutical industry and medical research