النامي في منطقة وادي سوف Drimia noctiflora المساهمة في دراسة السمية و الفعالية البيولوجية لمستخلصات

Abstract

This study aims to contribute to the evaluation of the toxicity and biological activity of extracts from Drimia noctiflora, including the aerial part and the underground part (bulbs). In vitro, phytochemical screening tests were conducted to qualitatively detect major secondary metabolites, quantitative assays were performed to estimate their total contents in the plant extracts, and the main biological activities were evaluated, including antioxidant activity (DPPH and FRAP assays), antibacterial activity, and the determination of sun protection factor (SPF).

Qualitative screening revealed the presence of flavonoids, tannins, alkaloids, triterpenes, sterols, saponins, and cardiac glycosides, while anthocyanins were absent. Saponins were detected only in the aerial part, whereas reducing compounds were found only in the underground part.

Quantitative analysis showed that the total polyphenol content was 73.4 ± 0.20 mg EAG/g in the aerial part and 40.65 ± 0.81 mg EAG/g in the underground part. The flavonoid content was 11.12 ± 0.12 mg EQu/g in the aerial part and 5.19 ± 0.30 mg EQu/g in the underground part. The total alkaloid content was 126.8 ± 0.88 µg/mL in the underground part and 108.3 ± 0.31 µg/mL in the aerial part.

Antioxidant activity assessed by the DPPH assay showed an IC₅₀ value of 0.29 ± 0.02 mg/mL for the aqueous extract of the aerial part, and 0.57 ± 0.09 mg/mL for the underground part. Using the FRAP assay, the EC₅₀ value was 22.32 ± 0.28 µg/mL for the aqueous extract of the aerial part, while the underground part showed no significant activity.

The antibacterial assay showed that the aqueous extract of the aerial part exhibited moderate activity against Klebsiella pneumoniae with an inhibition zone of 11.5 ± 2.1 mm, and against Escherichia coli with an inhibition zone of 15 ± 4.0 mm. The underground part also showed moderate activity with an inhibition zone of 11 ± 2.8 mm.

The SPF evaluation showed values of 13.3 for the aqueous extract of the aerial part and 20.7 for the methanolic extract, while the underground part showed SPF values of 12.8 (aqueous extract) and 18.1 (methanolic extract). An in vivo acute toxicity study of the aqueous extract of Drimia noctiflora indicated a safety margin with an LD₅₀ value greater than 2000 mg/kg.

In conclusion, this study highlights the promising biological potential of Drimia noctiflora, particularly due to its richness in bioactive secondary metabolites and its antioxidant and antibacterial activities. It also demonstrates low acute toxicity, suggesting that this plant could represent a valuable natural source for potential pharmaceutical and therapeutic applications.