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Item type:Publication, A study on the anti-Helicobacter pylori activity of three medicinal plant crude extracts from Cannabis sativa, Mitragyna speciosa and Phyllanthus emblica(2026-05-01)1 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Investigating the synergy of fast co-pyrolysis of spent coffee ground and disposed urban facemask: analysis of kinetics and product compositions(2025-12-01); Sricharoenchaikul, ViboonThis study investigates the thermo-kinetic behavior and product distribution during the co-pyrolysis of spent coffee grounds (SCG) and facemasks (FM). TGA was employed to evaluate the kinetics and thermodynamics of the pyrolysis process by segmenting the thermal decomposition into stage I (200 – 360 °C) and stage II (360 – 550 °C), while Py-GC/MS was used to analyse the product composition. SCG and FM blends with varying ratios by wt.% (SCG:FM = 100:0, 75:25, 50:50, 25:100, and 0:100) were subjected to pyrolysis at four heating rates (5, 10, and 30 °C/min). The decomposition curves were deconvoluted using Fraser-Suzuki deconvolution method into four peaks related to biomass pseudo-components and FM degradation. The deconvoluted curves showed potential synergistic interaction at the lignin and FM decomposition zone (460 – 500 °C). The kinetic analyses were carried out using three model-free methods to investigate the activation energy (Ea) and thermodynamics of co-pyrolysis. The lowest Ea value was obtained at SCG25 %FM%75 % (305.1 – 239 kJ/mol), mostly pronounced in stage II. Py-GC/MS analysis of the co-pyrolysis products demonstrates that the decomposition of polypropylene polymer of the FM promoted the formation of aliphatic hydrocarbons and reduces the overall acidity. This effect was further amplified at higher pyrolysis temperatures (450 – 650 °C). The blending ratio also plays a significant role, with a higher polymer content (SCG25 %FM75 %) leading to a more aliphatic products and a significant decline in carboxylic acids and anhydro-sugars. Moreover, co-pyrolysis reduced the N containing compounds significantly. Finally, policy implications and recommendations for co-pyrolysis adoption were incorporated. Overall, this study highlights the potential of utilizing waste material like SCG and FM for the sustainable production of valuable chemicals and fuels.3 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Insecticidal synergy of essential oils from Cymbopogon citratus (Stapf.), Myristica fragrans (Houtt.), and Illicium verum Hook. f. and their major active constituents(2021-06-01); Sittichok, SirawutThis study attempted to find safe and effective green insecticidal agents against Musca domestica L., which is a major public health pest in tropical and subtropical countries that have already developed resistance to synthetic pesticides. Plant essential oil-based insecticides are new, effective, and eco-friendly alternatives. Today, they are a housefly control method of choice. The study evaluated the insecticidal effect against M. domestica adults of essential oils (EOs) from Cymbopogon citratus (Stapf.), Illicium verum Hook. f., and Myristica fragrans (Houtt.) as well as their major active chemical constituents. Formulations of these individual and combined compounds were evaluated to see whether they were synergistic against M. domestica. Chemical compositions of these EOs were also analyzed by GC–MS. The major constituent of C. citratus was found to be geranial (45.4 %); that of I. verum was trans-anethole (94.0 %), and that of M. fragrans was α-pinene (21.6 %). Formulation CB3 (0.5 % I. verum EO + 0.5 % geranial) exhibited the highest synergistic effect (SI = 0.04), with 100 % knockdown and mortality rates, a 50 % knockdown time (KT<inf>50</inf>) of 4.0 min, and a 50 % lethal time (LT<inf>50</inf>) of 6.0 min. CB3 was more effective than 1% w/v cypermethrin, followed by CB5 (0.5 % M. fragrans EO + 0.5 % geranial), CB7 (0.5 % α-pinene + 0.5 % geranial), and CB8 (0.5 % geranial + 0.5 % trans-anethole). To conclude, some formulations of combined C. citratus, I. verum, and M. fragrans were strongly synergistic against M. domestica and more effective than cypermethrin. Moreover, since they have been long used as natural food ingredients and in traditional medicine, they are also safe for humans, non-target organisms, and the environment.