Harnessing the bioactive potential of the Algerian endemic Albuca amoena (Batt.) J.C. Manning and Goldblatt (Asparagaceae): new insights into antioxidant activity, enzyme inhibition, and phytochemical profile

Abstract

The bulbs of the herb Albuca amoena (Batt.) J.C. Manning and Goldblatt are traditionally used by the local populations in Algeria to counteract snakebites, scorpion stings, and leishmaniasis. A. amoena has also been used in traditional medicine to treat melanoma and various dermal infections and at the sedative level against pain or excitement. This plant contains bioactive compounds, such as phenolics and alkaloids. This work aimed to explore A. amoena as a potential source of bioactive molecules with food and pharmaceutical applications. For that purpose, ethanol crude extract and fractions (chloroform, ethyl acetate, n-butanol and aqueous) were obtained from the whole plant of this herb and evaluated for radical-scavenging activity (RSA) on 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and OH radicals, ferric-reducing antioxidant power (FRAP), silver ions (Ag⁺)-reducing potential, and for ferric-ion-based total antioxidant capacity. Extracts were also studied for in vitro inhibition of enzymes implicated on the onset of neurological diseases (butyrylcholinesterase: BuChE) and type 2 diabetes mellitus (T2DM, α-amylase). The total contents of phenolics (TPC), flavonoids (TFC), and tannins (TTC) were determined by colorimetric methods. Qualitative analyses of this herb were performed by ultra-high-performance liquid chromatography system coupled with electrospray ionization tandem mass spectrometry (UHPLC-ESI/MSMS). The ethyl acetate fraction had significant RSA and capacity to reduce iron, and silver ions (Ag⁺). The extracts had a higher activity toward BuChE and α-amylase, especially the ethanol crude extract with ethyl acetate and n-butanol fractions. The n-butanol fraction had the highest TPC (386.69 mg GAE/g DE) and flavonoid levels (34.59 CE/g DE), whereas the ethyl acetate fraction had the highest TTC (263.28 mg CE/g DE). UHPLC-ESI/MSMS identified 19 compounds in ethyl acetate and n-butanol fractions. Among these, one was steroid, two were terpenoids, one was fatty acid, four were phenolic acid derivatives, one was depsidone, and the remaining compounds were flavonoids. Results suggest A. amoena as a promising source of biologically active molecules with food, pharmaceutical, and biomedical applications.

Graphical abstract