Natural products continue to play an important role as a source of biologically active substances for the development of new drug.Streptomyces, Gram-positive bacteria which are widely distributed in nature, are one of the most popular sources of natural antibiotics. Recently, by using a bioassay-guided fractionation, an antimalarial compound, Gancidin-W, has been discovered from these bacteria. However, this classical method in identifying potentially novel bioactive compounds from the natural products requires considerable effort and is a time-consuming process. Metabolomics is an emerging “omics” technology in systems biology study which integrated in process of discovering drug from natural products. Metabolomics approach in finding novel therapeutics agent for malaria offers dereplication step in screening phase to shorten the process. The highly sensitive instruments, such as Liquid Chromatography-Mass Spectrophotometry (LC-MS), Gas Chromatography-Mass Spectrophotometry (GC-MS), and Nuclear Magnetic Resonance (¹H-NMR) spectroscopy, provide a wide range of information in the identification of potentially bioactive compounds. The current paper reviews concepts of metabolomics and its application in drug discovery of malaria treatment as well as assessing the antimalarial activity from natural products. Metabolomics approach in malaria drug discovery is still new and needs to be initiated, especially for drug research in Malaysia.

Diabetes mellitus is a chronic disease resulting from defects in insulin secretion, insulin action or both. The prevalence of diabetes has been increasing gradually over the last few decades. It has emerged as a global health concern that burdens public health and socioeconomic development. Oxidative stress plays a crucial role in developing diabetic complications affecting the eyes, kidneys, nerves, and heart. There are various established adverse effects of current conventional antidiabetic drugs. Due to this fact, plants have been chosen for developing new drugs as the bioactive compounds in plants have higher antidiabetic and antioxidant properties with low toxicity. Pomegranate peel is an agro-industrial waste that is rich in pectin. Pectin is a natural polysaccharide that has gained importance due to its pharmacological properties. In this study, pectin from pomegranate peel was extracted using ultrasound-assisted extraction to characterize the pectin and to evaluate its antioxidant and antidiabetic activity. Pomegranate peel pectin (PPP) was extracted using citric acid (solid-to-liquid ratio of 1:30 g/mL) at pH 2 under optimized conditions at 75°C for 40 min. A white sponge-like solid was obtained upon freeze-drying with a yield of 18.17%. The moisture content of pectin was 18.26% and it was found to be a low-methoxylated pectin with a degree of esterification (DE) of 31.07%. Fourier Transform Infrared Spectroscopy (FTIR) results showed that pectin from pomegranate peel was quite similar to commercial pectin. The antioxidant activity was evaluated using scavenging assays, 1,1- diphenyl-2-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Potential (FRAP) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) at 1 mg/mL (78.26% with IC50 value of 326.8 μg/mL, 79.12% with IC50 value of 83.63 μg /mL and 442.7 mg Fe2+/g, respectively). The antidiabetic activity was assessed using an α-amylase inhibition assay at 1 mg/mL (43.82%). These results suggest that PPP has the potential to be used as an antidiabetic and antioxidant agents.

As readily available medications for obesity and diabetes are reported to cause unwanted side effects, many natural alternatives to control obesity and diabetes are brought forward. Terengganu cherry (Lepisanthes fruticosa (Roxb.) Leenh) is an underutilized fruit in Malaysia that has limited study on its health benefits. Hence, this study aims to investigate the potential anti-obesity and anti-diabetic properties of fermented juice extract of Terengganu cherry (FTCJ). For anti-obesity effects, the impact of FTCJ and PTCJ on adipogenesis was assessed using 3T3-L1 cell differentiation assays. FTCJ inhibited lipid accumulation by 50.45%, 48.40%, and 67.12% at concentrations of 0.25 mg/mL, 0.5 mg/mL, and 0.75 mg/mL, respectively. Although PTCJ exhibited greater lipid accumulation reduction than FTCJ, this effect may be attributed to its cytotoxicity, as observed in cytotoxicity assays. For anti-diabetic effects, α-amylase and α-glucosidase inhibition assays were conducted. Both FTCJ and PTCJ showed no inhibitory activity against α-amylase. However, PTCJ demonstrated significantly higher α-glucosidase inhibition (99.11%) compared to FTCJ (31.72%) at 1.0 mg/mL. These findings suggest that while PTCJ exhibits stronger effects in both adipogenesis inhibition and α-glucosidase inhibition, its potential cytotoxicity raises concerns. In contrast, FTCJ exhibits promising anti-obesity effects with lower cytotoxicity, highlighting its potential as a natural alternative for managing obesity and diabetes. Further studies are recommended to explore its mechanisms and potential applications.