Unlocking Therapeutic Potential: Comprehensive Extraction, Profiling, and Pharmacological Evaluation of Bioactive Compounds from Eclipta alba (L.) Hassk. for Dermatological Applications

Abstract

Herbal medicine has been studied as an alternate approach to modern medicine as it is more cost-effective and accessible via natural sources. Eclipta alba (E. alba, L.) Hassk. is a weed plant abundantly distributed throughout different regions of the world and contains abundant bioactive compounds used for various skin conditions. In this review, we aimed to gather information from the literature about the extraction, separation, and identification of these bioactive compounds and their potential in skin diseases. Relevant studies published before August 2023 were identified and selected from electronic databases, including Scopus, SciFinder, ScienceDirect, Google Scholar, and Wiley Library, using the following keywords: Eclipta alba, Eclipta prostrata, phytochemicals, extraction, separation, isolation, identification, characterization, pharmacological activity, and skin conditions. Up-to-date extraction, separation, and identification methods of bioactive compounds from E. alba and their skin-related pharmacological activities are discussed in this review. As there are limitations regarding extraction, separation, and identification methods, and in-depth mechanistic and human studies of the skin-related pharmacological activities of bioactive compounds, these gaps are areas for future research to expand our understanding and broaden the potential applications of this medicinal weed plant, including the development of cosmeceutical and skincare products, anti-inflammatory agents, and formulations for dermatological treatments.

Keywords: Eclipta alba; Eclipta prostrata; extraction; identification; phytochemicals; separation.

Figure 1

Updated distribution map of Eclipta alba (L.) Hassk. [9] (Source: Global Biodiversity Information Facility Secretariat (GBIF), https://www.gbif.org/species/5384950 (accessed on 13 December 2023)).

Figure 2

Bioactive phytochemicals found in E. alba possess pharmacological activities relevant to various skin conditions, such as skin disease-causing microbes, inflammatory skin diseases, skin cancers, photo-aging, and skin pigmentation. Major phytochemicals have been reported as anti-inflammatory agents, such as luteolin (LT), luteolin-7-O-glucoside (L7G), wedelolactone (WDL), and demethyl wedelolactone (DWDL). Isolated compounds, WDL and eclalbasaponin (ECS), are promising antimicrobial agents. The luteolin (LT) displayed bioactivities to suppress skin inflammation and erythema. Furthermore, ursolic acid (UA) demonstrated a promising action for encounter skin pigmentation by suppressing melanin production.

Figure 3

Summary of different technologies used for the extraction, purification, and identification of bioactive compounds in E. alba. Both conventional and modern extraction techniques have been reported to explore the bioactive phytochemicals for skin benefits (SLE: solid–liquid extraction; SCE: solid–liquid continuous extraction; LLE: liquid–liquid extraction; MAE: microwave-assisted extraction; SAE: Soxhlet-assisted extraction; RE: reflux extraction; UAE: ultrasound-assisted extraction; UHPAE: ultrahigh pressure-assisted extraction; and HD: hydrodistillation). Further, numerous purifications, separations, characterization, and phytochemicals profiling techniques were utilized to isolate and identify the bioactive compounds from E. alba, including high-speed counter-current chromatography (HSCCC), high-performance liquid chromatography (HPLC), column chromatography (CC), ultraviolet–visible spectroscopy (UV–Vis), liquid chromatography–mass spectrometry (LC–MS), gas chromatography–mass spectrometry (GC–MS), thin-layer chromatography (TLC), high-performance thin-layer chromatography (HPTLC), Fourier transform infrared spectroscopy (FT–IR), nuclear magnetic resonance spectroscopy (NMR), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDS).