Chemical Composition and Antibacterial and Antioxidant Activities of Stem Bark Essential Oil and Extracts of Solanecio gigas

Abstract

Herbal medication developed from natural resources has to have antibacterial and antioxidant effects. The aim of this research is to look at the chemical makeup of Solanecio gigas (S. gigas) stem bark essential oil (EO), as well as the effectiveness of EO and extracts (chloroform, ethyl acetate, and methanol) against human pathogenic bacteria and their antioxidant activity. The GC-MS analysis identified 23 components, accounting for 98.7% of the total oil containing Methylene chloride (49.2%), sabinene (10.5%), 1-nonene (11.3%), Terpinen-4-ol (6.9%), Camphene (4.3%), γ-terpinene (3.6%), α-phellandrene (2.9%) β-myrcene (2.6%), 1,2,5-Oxadiazol-3-carboxamide, 4,4′-azobis-2,2′-dioxide (2.4%), α-terpinene (1.9%), 1-Octanamine, N-methyl- (1.9%), ρ-cymene (1.6%) as major components. The antibacterial efficacy of the EO and extracts (25, 50, 100, and 200 mg/ml) was demonstrated by the inhibitory zones (8.5 ± 0.47–23.3 ± 0.36 and 7.2 ± 0.25–22.0 ± 0.45 mm), respectively. The MIC values of the extracts and the EO were 120–150 and 240 to <1100 μg/ml, respectively. The EO also demonstrated a significant antibacterial impact. The EO and methanolic extract had free radical scavenging activities with IC50 value, 13.8 ± 0.48 and 4.2 ± 0.04 μg/ml, respectively. In comparison to the other extracts, the methanolic extract had the greatest phenolics (100.2 ± 0.13 μg GAE/mg of dry extract) and flavonoid contents (112.1 ± 0.18 μg CE/mg of dry extract).

Phytochemical constituents, antioxidant and antibacterial activities of Plectocephalus varians (A. Rich) C. Jeffrey ex Cufod root extracts

“…are implicated in the toxicity of microorganisms through disruption of cell membranes and spontaneous out ow of intracellular components that can potentially culminate in the death of pathogenic bacteria strains [21,42]. The pronounced antibacterial activity of the MRE is consistent with the TPC and TFC as reported elsewhere [40].…”

“…Overall, relatively highest antibacterial activities were recorded by the MRE against Klebsiella pneumoniae (20 ± 0.04 mm) and Staphylococcus aureus (17 ± 0.12 mm); and ARE on Escherichia coli (17 ± 0.15 mm). Consistent with this, Yitayeh et al, [40] also reported the superior antibacterial activity of the methanolic Solanecio gigas stembark extract as compared to the less polar ethyl acetate and chloroform extracts on the same bacteria strains. The signi cant and better antibacterial activity of the MRE of P. varians might be attributed to the presence of high concentrations of avonoids, alkaloids, phenols, terpenoids, tannins, etc.…”

“…This might be attributed to the magnitude in the polarity of the extraction solvent which is vital to abstract polar phytoconstituents from P. varians roots such as avonoids based on the principle of "like dissolve like". Flavonoids are another class of relatively polar phytochemicals that contain hydroxyl groups implicated in absorbing and neutralizing free radicals, quenching singlet and triplet oxygen, or decomposing peroxides [40] and thereby ameliorate the undesirable effects of free radicals such as oxidative stress in cells.…”

“…In this method, quercetin was used as standard and the TFC was estimated as mg of quercetin equivalents/100 g of dry samples. In brief, 1 mL of standard quercetin solutions and each HRE, ARE and MRE solution (20,40,80,150, 160 and 320 ppm) was transferred into 25 mL volumetric ask and 4 mL of distilled water and 0.3 mL of NaNO 2 were added to each ask. After 5 min of incubation, 0.3 mL of 10% aluminum chloride followed by 2 mL of 1M NaOH (6 th min) was added.…”

Ethnobotanical study of endemic and non-endemic medicinal plants used by indigenous people in environs of Gullele botanical garden Addis Ababa, central Ethiopia: A major focus on Asteraceae family

“…The other Asteraceae plants in our studies with reported bioactivities are Lactuca inermis Forssk and Solanecio gigas (Vatke) C.Jeffrey ( Janbaz et al, 2013 ). Both of them are known to have antimicrobial activity against a variety of microbes ( Molla Yitayeh and Monie Wassihun, 2022 ).…”