DSpace-CRIS

Now showing 1 - 4 of 4

Some of the metrics are blocked by your
consent settings
Extraction of Gnetum gnemon L. (Melinjo) Leaves Using Deep Eutectic and Conventional Solvents: Phytochemical Contents, Antioxidant Capacity, and Toxicity Assessment
(2026-02-01)
Rushdy, Muhammad Naufal Qaweim
;
Awang, Mohd Azrie
;
Benjamin, Mohammad Amil Zulhilmi
;
Saini, Aniza
;
Mohd Rosdan, Muhammad Daniel Eazzat
Gnetum gnemon L. (Melinjo) is widely recognised for its rich bioactive compounds with potential health benefits. This study evaluates the effectiveness of deep eutectic solvents (DESs) and conventional solvents using ultrasound-assisted extraction on the extraction efficiency, antioxidant activity, and toxicity of G. gnemon leaf extracts (GGLE). Four DESs, namely choline chloride-lactic acid (ChCl-LA), choline chloride-glycerol (ChCl-Gly), betaine-lactic acid (Bet-LA), and L-proline-citric acid (LP-CA), were compared with conventional solvents, namely water, methanol, and ethanol. Extraction performance was evaluated based on crude extract yield (CEY), phytochemical content through chlorogenic acid content (CAC), total phenolic (TP), and total flavonoid (TF), as well as antioxidant activity assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. Toxicity was assessed using the brine shrimp lethality assay (BSLA). Among all solvents, ChCl-LA yielded the highest CEY (20.23 ± 0.68%), CAC (13.96 ± 0.31 µg/g), TP (92.54 ± 0.74 mg GAE/g), DPPH (84.95 ± 1.49%), ABTS (91.25 ± 0.34%), and FRAP (481.14 ± 2.31 mg TE/g) (p < 0.05), while exhibiting no toxicity with a high LC₅₀ value (6,339.43 µg/mL). Nonetheless, ethanol yielded the highest TF (2.98 ± 0.47 mg QE/g), followed by ChCl-Gly (2.45 ± 0.27 mg QE/g), although non-significant (p > 0.05), with ChCl-LA (2.14 ± 0.27 mg QE/g) placed as the third highest. Overall, DESs, particularly ChCl-LA, demonstrated promising extraction efficiency and non-toxicity compared to conventional solvents, supporting their potential as greener alternatives for extracting bioactive compounds from G. gnemon leaves.
Some of the metrics are blocked by your
consent settings
Acaricidal activities of essential oil emulsions in controlling different mite pests
(2024-07-01)
Doungnapa, T.
;
Pumnuan, J.
;
Lakyat, A.
;
Thipmanee, K.
The result revealed the citronella grass emulsions had a highly toxic effect to the African red mite that presented LC50 and LC90 with 0.146 and 0.303%, respectively. While citronella grass emulsion at concentration 0.4% was able to control those 3 mite pest species in greenhouse or field conditions, when it presented the mite mortality with >80% compared with control group.
Some of the metrics are blocked by your
consent settings
Polycyclic Aromatic Hydrocarbons Occurrences in Biomass Char and Its Mitigation Approaches: A Mini Review
(2023-08-01)
Mohd Nor Azman, Nur Aina Najwa
;
Asmadi, Mohd
;
Amin, Nor Aishah Saidina
;
Shamjuddin, Amnani
;
Mohammad Zainol, Muzakkir
Biochar is a porous fine-grained substance produced from the pyrolysis technology of biomass that can be commercially used as a soil conditioner to promote soil fertility. Biochar is characterized by high carbon content, stability, and porosity. However, organic pollutants residue of polycyclic aromatic hydrocarbons (PAHs) is also formed during the pyrolysis of biochar. The high concentration of PAHs adversely degrades the quality of biochar for soil amendment application. Meanwhile, highly toxic-PAHs concentration may pose a potential threat to both human health and the environment. The total PAHs yield is mainly influenced by the pyrolysis condition and feedstock resource. This review aims to discuss the conversion pyrolysis technology of biochar and factors that may influence the PAHs formation. The key research findings from this literature will lead to some strategies to minimize the PAHs compound in biochar by controlling the pyrolysis conditions through higher pyrolysis temperature, carrier gas flow, and prolonged pyrolysis time or by selecting suitable feedstock with lower lignin content.
Some of the metrics are blocked by your
consent settings
Acaricidal activity of essential oil nanoemulsion against the african red mite (Eutetranychus africanus)
(2021-04-01)
Doungnapa, Thanaporn
;
Pumnuan, Jarongsak
;
Insung, Ammorn
The African red mite (Eutetranychus africanus [Tucker]) is an important pest species of some economic plants. The objective of the present study was to evaluate the effectiveness of nanoemulsions consisting of citronella grass, lemongrass, clove, and cinnamon essential oils and their main chemical compounds against the African red mite; their toxicity, egg-laying inhibition, and repellent effect on the mite were determined. Essential oil nanoemulsions (nEOs) were prepared by mixing the essential oils with different surfactants and co-surfactants. Approximately 10 to 15 female mites were transferred to treated leaves placed on soaked cotton and kept in a Petri dish. Mite mortality and number of eggs laid were checked after 24 h. As for the repellency test, the selected test consisted of dipping a half leaf into the nEOs, while the other half leaf was dipped in a control (water). The repellency rate was evaluated after 24 h. Results revealed that citronella grass nEOs exhibited a highly toxic effect on the mite and only a 0.6% concentration caused 100% mite mortality. Geraniol, one of the main chemical compounds of citronella grass, represented the highest egg-laying inhibition at a 0.2% concentration with a mean of 0.1 egg compared with 4.7 eggs in the control. Furthermore, nEOs from citronella grass at a 0.1% concentration were extremely repellent against the mite with 95% repellency after 24 h. Therefore, the citronella grass essential oil nanoemulsion is appropriate for use to effectively control the African red mite.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results