METHODS: In the current study, the crude methanol and fractionated extract of the rhizomes of Alpinia pahangensis were investigated for their antioxidant activity using four different assays namely, the DPPH scavenging activity, superoxide anion scavenging, β-carotene bleaching and reducing power assays whilst their phenolic contents were measured by the Folin-Ciocalteu's method.In vitro neutral red cytotoxicity assay was employed to evaluate the cytotoxic activity against five different cancer cell lines, colon cancer (HCT 116 and HT-29), cervical cancer (Ca Ski), breast cancer (MCF7) and lung cancer (A549) cell lines, and one normal cell line (MRC-5). The extract that showed high cytotoxic activity was further investigated for its chemical constituents by GC-MS (gas chromatography-mass spectrometry) analysis.
RESULTS: The ethyl acetate fraction showed the strongest DPPH radical scavenging (0.35 ± 0.094 mg/ml) and SOD activities (51.77 ± 4.9%) whilst the methanol extract showed the highest reducing power and also the strongest antioxidant activity in the β-carotene bleaching assays in comparison to other fractions. The highest phenolic content was found in the ethyl acetate fraction, followed by the crude methanol extract, hexane and water fractions. The results showed a positive correlation between total phenolic content with DPPH radical scavenging capacities and SOD activities. The hexane fraction showed potent cytotoxic effect against KB, Ca Ski and HCT 116 cell lines with IC₅₀ of 5.8 ± 0.1 and 9.1 ± 2.0 ug/ml, respectively. The major components of hexane fraction analysed by GC-MS analysis were mostly methyl esters.
CONCLUSIONS: The current study suggests that the methanol extract and ethyl acetate fraction of A. pahangensis is a potential source of natural antioxidant for protective as well as prevention of life-threatening diseases. The hexane fraction of A. pahangensis may have the potential to be developed into therapeutic option for treating cancer.
MATERIALS AND METHODS: Total phenolic content, antioxidant activity and phenolic compounds were determined. Then, three groups of rats (control, HCl/ Ethanol-induced ulcer, and orally administered honey) were used for the determination of gastro-protective effect of Sidr honey.
RESULTS: Total phenolic content, total flavonoid content, and DPPH activity of the honey sample were determined as 47.35±3.35 mg GAE/ 100 g, 2.13±0.17 mg QE/ 100 g, and 229.24±0.02 mg/mL, respectively. Oral pretreatment of rats with honey (1.2 g/Kg body weight orally at an interval of 2 days) protected gastric mucosa against HCl/Ethanol-induced damage by decreasing ulcer score, the volume and acidity of gastric juice and increasing pH.
CONCLUSION: These results were confirmed by the histological assessment, which demonstrated a significant gastro-protective activity of Saharian (Sidr) honey against HCl/Ethanol-induced stomach ulcer. Plasma tumor necrosis factor-α, IL-6 and PGE2 were also measured. Sahara honey significantly decreased the plasma TNF-α, PGE2, and IL-6 concentrations.
PURPOSE: The phytochemical profile of O. aristatus was investigated at different storage durations for quality comparison.
METHODS: The phytochemicals were extracted from the leaves and stems of O. aristatus using a reflux reactor. The extracts were examined for total phenolic and flavonoid contents, as well as their antioxidant capacities, in terms of radical scavenging, metal chelating and reducing power. The phytochemical profiles were also analyzed by unsupervised principal component analysis and hierarchical cluster analysis, in relation to the factor of storage at 4 °C for 5 weeks.
RESULTS: The leaf extract was likely to have more phytochemicals than stem extract, particularly caffeic acid derivatives including glycosylated and alkylated caffeic acids. This explains higher ratio of total phenolic content to total flavonoid content with higher antioxidant capacities for the leaf extracts. Rosmarinic acid dimer and salvianolic acid B appeared to be the major constituents, possibly contributing to the previously reported pharmacological properties. However, the phytochemical profiles were found changing, even though the extracts were stored in the refrigerator (4 °C). The change was significantly observed at the fifth week based on the statistical pattern recognition technique.
CONCLUSION: O. aristatus could be a promising source of rosmarinic acid and its dimer, as well as salvianolic acid B with remarkably antioxidant properties. The phytochemical profile was at least stable for a month stored at 4 °C. It is likely to be a good choice of herbal tea with comparable radical scavenging activity, but lower caffeine content than other tea samples.
METHODS: Cocoa pod extract (CPE) composition was accomplished using UHPLC. The antioxidant capacity were measured using scavenging assay of 1,2-diphenyl-2-picrylhydrazyl (DPPH), β-carotene bleaching assay (BCB) and ferric reducing antioxidant power (FRAP). Inhibiting effect on skin degradation enzymes was carried out using elastase and collagenase assays. The skin whitening effect of CPE was determined based on mushroom tyrosinase assay and sun screening effect (UV-absorbance at 200-400 nm wavelength).
RESULTS: LC-MS/MS data showed the presence of carboxylic acid, phenolic acid, fatty acid, flavonoids (flavonol and flavones), stilbenoids and terpenoids in CPE. Results for antioxidant activity exhibited that CPE possessed good antioxidant activity, based on the mechanism of the assays compared with ascorbic acid (AA) and standardized pine bark extract (PBE); DPPH: AA > CPE > PBE; FRAP: PBE > CPE > AA; and BCB: BHT > CPE > PBE. Cocoa pod extract showed better action against elastase and collagenase enzymes in comparison with PBE and AA. Higher inhibition towards tyrosinase enzyme was exhibited by CPE than kojic acid and AA, although lower than PBE. CPE induced proliferation when tested on human fibroblast cell at low concentration. CPE also exhibited a potential as UVB sunscreen despite its low performance as a UVA sunscreen agent.
CONCLUSIONS: Therefore, the CPE has high potential as a cosmetic ingredient due to its anti-wrinkle, skin whitening, and sunscreen effects.