Ni Luh Rustini

Identification of Active Antioxidant Compounds from Ungu Leaf Ethanol Extract (Graptophyllum pictum L. Griff)

Introduction

identification of active antioxidant compounds from ungu leaf ethanol extract (graptophyllum pictum l. Griff). Identify active antioxidant compounds from Ungu Leaf (Graptophyllum pictum L. Griff) ethanol extract, revealing stigmasterol compounds like stigmasta-5,22-dien-3-ol.

Abstract

This study was conducted to determine the chemical compounds contained in ungu leaf ethanol extract that has antioxidant properties. Ungu leaf powder (2000 g) was extracted with 10,000 mL of 96% ethanol yielding 51.77 g thick purple-green viscous extract. The result of phytochemical test on ungu leaf ethanol extract showed that the extract contained flavonoid, saponin, phenolic and steroid, with the highest content being steroid. The separation of the ethanol extract was carried out by column chromatography using silica gel as a stationary phase and a mixture of n-hexane: dichloromethane: ethyl acetate (2: 1: 1) as the mobile phase, yielding 10 fraction groups. Fraction F1 is relatively pure, then identified with UV-Vis, IR, and GCMS spectrophotometers. The results of identification with UV-Vis, IR, and GC-MS spectrophotometers showed that ungu leaf ethanol extract containing antioxidant activity contained stigmasterol compounds, namely: stigmasta-5,22-dien-3-ol and stigmast acid-5-en-3-ol.

Review

This study presents an investigation into the chemical constituents responsible for the purported antioxidant activity of *Graptophyllum pictum* L. Griff ethanol extract. The authors systematically performed an ethanol extraction, followed by phytochemical screening and column chromatographic separation. A key strength lies in the comprehensive analytical approach, employing UV-Vis, IR, and GC-MS spectrophotometry to identify compounds within a relatively pure fraction (F1). The primary finding – the identification of stigmasterol (stigmasta-5,22-dien-3-ol) and stigmast acid-5-en-3-ol – is significant, as stigmasterol is a well-known plant sterol with documented antioxidant and other beneficial biological activities. This work lays foundational groundwork for understanding the phytochemical basis of ungu leaf's traditional medicinal uses. Methodologically, the study demonstrates a robust workflow from large-scale extraction to initial compound isolation. The preliminary phytochemical screening, which indicated the presence of flavonoids, saponins, phenolics, and steroids (with steroids being the most abundant), effectively guided the subsequent identification efforts. The choice of multiple spectroscopic techniques for compound characterization strengthens the identification of stigmasterol and its derivative. However, the abstract uses the phrase "ungu leaf ethanol extract containing antioxidant activity contained stigmasterol compounds," implying the extract's antioxidant activity was already established. While the title suggests the identification of "active" compounds, the abstract does not detail the methods used to quantify the extract's initial antioxidant capacity or to directly link the identified stigmasterol compounds to this specific activity. A notable limitation of the abstract, and consequently the study as presented, is the absence of any data demonstrating the direct antioxidant activity of the isolated stigmasterol compounds. While stigmasterol is recognized for its properties, the study would be significantly strengthened by *in vitro* antioxidant assays (e.g., DPPH, FRAP, ABTS) performed on the isolated compounds, comparing their activity to the crude extract. Future research should focus on isolating these compounds in higher purity and quantity, directly assessing their antioxidant potential, and investigating dose-response relationships. Furthermore, exploring the other nine fractions obtained from column chromatography could reveal additional bioactive compounds. Despite these suggestions, this study makes a valuable contribution by identifying specific steroidal compounds in *Graptophyllum pictum* extract, providing a strong basis for further targeted research into its medicinal properties.

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