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2′,4′-Dihydroxy-6′-methoxy-3′,5′-dimethyl chalcone (DMC) is a biological flavonoid that is present in the fruits of Syzygium nervosum (Ma-Kiang in Thai). Microwave-assisted extraction (MAE), which utilizes microwave radiation to heat the extraction solvent quickly and effectively, was used to recover DMC-rich extract from Syzygium nervosum fruit. To determine the DMC content, a highly accurate and precise HPLC technique was developed. The influences of MAE conditions, including the solid–liquid ratio, microwave power, and microwave duration on the content of DMC, were sequentially employed by a single factor investigation and response surface methodology (RSM) exploratory design. The predicted quadratic models were fitted due to their highly significant (p < 0.0001) and excellent determination coefficient (R2 = 0.9944). The optimal conditions for producing DMC-rich extract were a ratio of sample to solvent of 1:35 g/mL, a microwave power of 350 W, and a microwave time of 38 min. Under the optimal MAE setting, the DMC content reached 1409 ± 24 µg/g dry sample, which was greater than that of the conventional heat reflux extraction (HRE) (1337 ± 37 µg/g dry sample) and maceration (1225 ± 81 µg/g dry sample). The DMC-rich extract obtained from MAE showed stronger anticancer activities against A549 (human lung cancer cells) and HepG2 (human liver cancer cells) than the individual DMC substance, which makes MAE an effective method for extracting essential phytochemicals from plants in the nature.

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This study was intended to assess the role of carboxymethyl cellulose (CMC) as a chelating agent in the synthesis of barium hexaferrite (BaFe12O19:BaF). The effect of varying concentrations of CMC was studied via the sol-gel auto-combustion method following the requirements of green chemistry synthesis. The formation of BaF nanoparticles was confirmed using XRD, SEM, EDS, VSM, FTIR and UV-Vis-DRS techniques. The characterized XRD peak indicates the formation of good quality crystalline samples at 6% (w/v) of CMC concentration. SEM analysis suggested that the synthesized BaF is spherical, with sizes ranging from 10-15 nm. The M-H hysteresis loops obtained for the samples showed their soft and hard magnetic behaviour. With the increasing CMC concentration, magnetism becoming harder and an increase in the Ms value can be observed. The UV-Vis-DRS techniques revealed that the band gap energy of synthesized BaF increased with an increase in the concentration of CMC.

Nipa palm vinegar (NPV) is an essential product from the Pak Phanang district in the Nakhon Si Thammarat Province, Thailand. NPV is used for cooking and its antibacterial activity reduces dependency on toxic chemicals such as antibiotics and preservative foods. Using NPV as the precursor, nipa palm vinegar–graphene quantum dots (NPV-GQDs) were successfully synthesized through pyrolysis. Preliminary screening of the antibacterial activities of NPV and NPV-GQDs against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacterial strains were determined by using the agar well diffusion method. The broth macro-dilution method determined the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The diameter of the inhibition zones of S. aureus and E. coli reached 29.30 mm and 23.50 mm, respectively. The MIC of NPV-GQDs against S. aureus and E. coli was 6.25 mg/mL and 12.50 mg/mL, respectively, whereas the MBC of NPV-GQDs against S. aureus and E. coli was 50.00 mg/mL. These results signify the potential healthcare application of NPV-GQDs as high-quality and valuable antimicrobial agents, thereby reducing chemical usage toxic to the body in the future.