Free radicals contribute to the pathophysiology of degenerative diseases which increase mortality globally, including mortality in Indonesia. Amomum compactum Soland. Ex Maton fruit from the Zingiberaceae family, also known as Java cardamom, contains secondary metabolites that have high antioxidant activities. The antioxidant activity of the methanol extract of Java cardamom fruit correlates with its flavonoid and phenolic compound contents, which can be affected by different methods and durations of extraction. This study aimed to measure and compare the effects of extraction methods and durations on total flavonoid and phenolic contents (TFCs and TPCs) and subsequent antioxidant activities by the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical, ferric reducing antioxidant power (FRAP), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), and cupric ion reducing antioxidant capacity (CUPRAC) assays. Methanol extracts of Java cardamom were produced by continuous shaking (CSE), microwave-assisted (MAE), or ultrasonic-assisted extractions (UAE) for three different durations. CSE for 360 min resulted in the highest TFCs (3.202 mg Quercetin Equivalent/g dry weight), while the highest TPCs (1.263 mg Gallic Acid Equivalent/g dry weight) were obtained by MAE for 3 min. Out of the investigated methods, MAE for 3 min resulted in the highest antioxidant activity results for the extracts. We conclude that the polyphenolic antioxidant yield of Java cardamom depends on two parameters: the method and the duration of extraction.

Orthosiphon aristatus (Blume) Miq. of the Lamiaceae family, called as kumis kucing in Indonesia, is a valuable medicinal plant for their pharmacological properties. The present study comprised of fifteen genotypes of O. aristatus was undertaken to evaluate the genotypes based on phytochemical content and pharmacological activities of leaves ethanol extract. Chemometric analysis (correlation and principal component analysis) was also used to investigate the genetic variability based on phytochemical content and pharmacological activities of O. aristatus genotypes. Results of phytochemical characterization showed that total phenolic ranged from 1.48 to 36.08 (maximum in A15) mg GAE/g DW, total flavonoid ranged from 0.10 to 3.07 (maximum in A15) mg QE/g DW, sinensetin ranged from 0.36 to 4.02 (maximum in A11) mg/g DW, and rosmarinic acid ranged 0.06 to 7.25 (maximum in A7) mg/g DW. Antioxidant activity was tested using DPPH and FRAP assay. Antioxidant results showed that DPPH ranged from 1.68 to 15.55 (maximum in A15) μmol TE/g DW and FRAP ranged from 0.07 to 1.60 (maximum in A1 and A7) μmol TE/g DW. The genotype A8 showed the highest cytotoxic activities against HeLa (66.25%) and MCF-7 (61.79%) cell lines. Maximum α-glucosidase inhibitory activity was recorded in genotype A2 with the value of 62.84%. The genotypes A1, A2, A7, A11, and A15 were identified as superior based on their phytochemicals content and pharmacological activities coupled with chemometric analysis. This finding is important for breeding studies and also the pharmaceutical perspective of O. aristatus.

Calvindi J, Syukur M, Nurcholis W. 2020. Investigation of biochemical characters and antioxidant properties of different winged bean (Psophocarpus tetragonolobus) genotypes grown in Indonesia. Biodiversitas 21: 2420-2424. Winged bean, Psophocarpus tetragonolobus (L) DC, is described as having antioxidant properties. This work evaluated the biochemical and antioxidant characteristics of the P. tetragonolobus genotypes. Twelve-winged bean genotypes were calculated for total phenolic content (TPC) and total flavonoid content (TFC) of biochemical characters and antioxidant properties by using four methods: 2,2-diphenyl picrylhydrazyl (DPPH), cupric reducing antioxidant power (CUPRAC), ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant capacity (TEAC). The plant material was grown in the same location conditions in Indonesia. The total phenolic content varied from 154.6 to 161.5 mg GAE/ 100 g, and flavonoid ranged from 105.2 to 112.4 mg QE/ 100 g fresh weight. The antioxidant capacities were 30.6 - 47.0, 140.4 - 167.6, 66.9 - 170.8, and 28.0 - 52.4 µmol TE/ 100 g fresh weight as calculated by the DPPH, TEAC, FRAP, and CUPRAC assays, respectively. The antioxidant activities were significantly correlated with the polyphenol content of winged bean genotypes fruits. The genotypes TU, L3, H3U, H1P, and TH were recognized higher based on their TPC, TFC, and antioxidant activities, indicating that these genotypes to be promising for further breeding program and commercial purposes.

Khumaida N, Syukur M, Bintang M, Nurcholis W. 2019. Phenolic and flavonoid content in ethanol extract and agro-morphological diversity of Curcuma aeruginosa accessions growing in West Java, Indonesia. Biodiversitas 20: 656-663. Curcuma aeruginosa is a rhizomatous medicinal plant with beneficial pharmacological activities. The aim of this work was to analyze the agro-morphological, extract yield, and phenolic content of ten C. aeruginosa accessions which were collected from different locations in Indonesia. Cultivation was carried out in the open field in West Java of Indonesia using a completely randomized design. Qualitative and quantitative parameters were used to investigate agro-morphological traits. Total phenolic and total flavonoids contents were determined in ethanol extracts of samples. The plants were phenotypically diverse, in which there were significant variations among the ten C. aeruginosa accessions in number of leaves, plant height, number of shoots, fresh weight of rhizome, and dry weight of rhizome characters. Variability in the total phenolic and total flavonoid contents ranged from 29.08-46.92 mg GAE/g, and 21.31-33.81 mg QE/g, respectively. Six accessions had high phenolic content and extract yield. Therefore, these accessions could be utilized for commercial scale and also showed a high potency for medicinal plant breeding programs.