1H-NMR BASED METABOLOMICS AND BIOACTIVITY AF MATOA (POMETIA PINNATA) LEAVES AT VARIOUS AGES

• Main Author: Herliana
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/85644
• Institution: Institut Teknologi Bandung

Matoa (Pometia pinnata) leaf is a Papuan plant whose fruit tastes like longan, rambutan, and durian. It is traditionally used to treat fever, diabetes, hypertension, and skin diseases. However, the metabolite profile of matoa leaves is still limited in the literature. In this study, the metabolite profile of matoa leaves was evaluated by 1H NMR-based metabolomics method. The ?-glucosidase inhibitory assay and antioxidant (DPPH and FRAP) activity tests were applied to examine the bioactivity of matoa leaves in this study. In addition, this study also determined the total phenolic content and total flavonoid content of matoa leaf samples. This study used four matoa leaf samples with different ages, including old leaves, mature leaves, juvenile leaves, and young leaves. The matoa leaf samples used in this study came from Parakan Mas, Cisaranten Endah, Arcamanik, Bandung City, West Java. Each leaf sample was freeze dried, pulverised, and extracted with CD3OD:D2O (7:3). The extracted supernatant was then measured with a 1H NMR spectrometer. Overall, this study has successfully identified 19 metabolites from matoa leaf samples including primary metabolites and secondary metabolites such as ?glucose, fructose, amino acids, kaempferol, quercetin, and several derivatives. The data obtained from the measurement results were processed and evaluated by multivariate statistical analysis using Principal Component Analysis (PCA) as the main model. The score plot of the PCA model successfully classified the matoa leaf samples based on their age. Investigation of loading plot showed that fructose, alanine, valine, and leucine were the distinguishing compounds for old matoa leaves. Mature leaves were distinguished by glucose, lactic acid and quercetin. Meanwhile, the discriminant compounds of juvenile leaves were kaempferol-3- Orhamnoside and asparagine, and the characteristic compounds of young matoa leaf samples are rutin, kaempferol, proantocyanidin A2 and siringic acid. All four types of matoa leaves have been evaluated for antioxidant activity using DPPH and FRAP methods. However, the antioxidant activity of the four types of matoa leaves is not too different and is categorised as active (IC50 DPPH value = 6-10 ppm; and EC50 FRAP = 14-20 ppm). The ?-glucosidase inhibitory activity of matoa leaves was categorised as active with IC50 values ranging between = 1-6 ppm. Total phenolics and flavonoids of the four matoa leaf samples have been evaluated by Folin-Ciocalteu method and 10% aluminium chloride colorimetric method. The results showed that the four matoa leaves had similar phenolic contents. Meanwhile, the juvenile leaf sample had the smallest total flavonoids (14.28 ± 1.54 mgQE/g). The results of this study showed that all four matoa leaves have antioxidant activity as well as ?-glucosidase inhibitor activity with active category. To the best of our knowledge, this is the first report on the metabolomic evaluation of matoa leaves by 1H-NMR approach.