This study aimed to fractionate Alternanthera sessilis Red (ASR) crude extracts and determine their antioxidant activities as well as the related active components in the whole plant. ASR was extracted with water and ethanol, and further separated using a Sephadex LH-20 column. Following the assessments of the polyphenolic contents and antioxidant activities of crude extracts (H2 OASR and EtOHASR ) and fractions, a HPLC-QToF analysis was performed on the crude extracts and selected fractions (H2 OASR FII and EtOHASR FII). Three water fractions (H2 OASR FI, FII and FIII) and four ethanolic fractions (EtOHASR FI, FII, FIII and FIV) were derived from their crude extracts, respectively. EtOHASR FII exhibited the greatest total phenolic content (120.41 mg GAE/g fraction), total flavonoid content (223.07 mg RE/g fraction), and antioxidant activities (DPPH IC50 =159.43 μg/mL; FRAP=1.93 mmol Fe2+ /g fraction; TEAC=0.90 mmol TE/g fraction). Correlation analysis showed significant (p<0.01) positive correlations between both TPC (r=0.748-0.970) and TFC (r=0.686-0.949) with antioxidant activities in the crude extracts and fractions. Flavonoids were the major compounds in the four selected samples tentatively identified using HPLC-QToF-MS/MS, with the highest number of 30 polyphenol compounds detected in the most active fraction, EtOHASR FII.
The Malaysian Dietary Guidelines (MDG) with eight key messages were first published in 1999. An updated version consisting of 14 key messages is being developed. The objective of this study was to evaluate the understanding of five key messages of the updated MDG among adults aged 18-59 years in Kuala Lumpur. A total of 773 adults comprising 330 Malays, 364 Chinese and 79 Indians were included in the study. A self-administrated questionnaire was used to obtain demographic data and to determine the level of understanding of key words and messages to be included in the new MDG. The results showed that 63% of the subjects were not aware of the existence of the MDG published in 1999. Overall, the understanding of the five messages in the updated MDG was moderate with a mean score of 60.0 ± 16.5. Between 52% to 93% of the subjects did not understand such key words as serving size, sedentary habits, blended vegetable oil and shortenings. The mean scores of understanding were significantly higher (p< 0.05) among the Chinese subjects (61.3 ± 17.8) than Malays (58.6 ± 14.2) and Indians (60.0 ± 18.9). The younger subjects (61.2 + 16.0) scored significantly (p< 0.05) higher than the older (58.7 ± 17.0) counterparts. There was also a significant association between the level of understanding of MDG with education level (p< 0.001) and occupational status (p< 0.001), respectively. This study suggests that some key words and messages in the updated MDG should be simplified to ensure that they are understood by Malaysians.