S. alata is found throughout Africa, including Ghana, Brazil, Australia, Egypt, India, Somalia, Sri Lanka, and other countries [1]. The entire plant is used to cure impetigo, ulcers, helminthiasis, and as a purgative [2]. Senna alata leaf extract has been discovered to help reduce blood sugar levels. Senna alata is also used to treat gastrointestinal infections, intestinal worms, typhoid fever, poison, hepatitis, yellow fever [3], wounds, and viral infections [3].

Chemicals 

Methanol, Folin-ciocalteu reagent, sodium carbonate, Gallic acid, 1, 10-phenanthroline, iron (II) sulfate (FeSO₄₎, DPPH (1, 1-diphenyl–2 Picrylhydrazyl), sodium nitroprusside, griess reagent, copper sulfate (CuSO₄), pyrocatechol, thiourea, acetic acid, ethanol, ammonia solution, Quercetin, sodium nitrite (NaNO₂), aluminum chloride (AlCl₃), sodium hydroxide (NaOH), _,L-ascorbic acid, sodium phosphate, ammonium molybdate.

Plant Material

Fresh leaves of Senna alata were collected and identified by the Department of Botany, Niger Delta University, Bayelsa State. Plant was collected in November, 2021 in the pharmacognosy botanical garden.

Methods

Preparation of Methanoic Extract of Senna Alata: Senna alata was harvested and dried in the shade for 14 days (Two weeks). The dried leaves were later grounded to a fine powder. Crushed leaves were soaked in 1500ml methanol for three days (72 hours). The crude extract was then filtered and evaporated to dryness. The dark paste was then stored in the refrigerator to be used later.

Antioxidant Assays

Total phenol was by the method reported by Singleton et al. [4] and Demiray et al. [5], total flavonoid by Zhishen et al. [6] total antioxidant by Prieto et al. [7] iron (ll) complexation by Minotti and Aust, [8] and Puntel et al. [9] DPPH quenching by Gyamfi et al. [10] nitric oxide quenching by Marcocci et al. [11] copper coordination by Torres-Fuentes et al., 2011, hydroxyl radical sequestering by Jin et al. [12].

RESULTS AND DISCUSSION 

Percentage yield = 17.36%

Nitric oxide (NO) and DPPH radicals were also sequestered by Senna alata extract is concentration dependent from 0.1 – 1 mg/ml concentration of Senna alata the percentage sequestration of NO and DPPH increases from 6.49±1.78 % - 74.73±1.41 %  and20.41±1.58 % -  87.216±1.39 % as shown in table 2 above.

The hydroxyl radical is the most notorious ROS, in biological system. It is also produced by many metabolic reactions, Senna alata extract has the ability to quench the production of this radical. At concentrations of 0.1 mg/ml – 1mg/ml Senna alata scavenged the hydroxyl radical at 24.93±1.06 % - 92.84±2.97 % as shown on table 3 above. Gallic acid as standard also showed a higher level of scavenging of the hydroxyl radical.

Copper and iron coordination are important medical procedures, Senna alata chelation of copper is concentration dependent that is from 0.1 – 1 mg/ml concentration of Senna alata the percentage chelation of copper increases from 16.60±1.08 – 86.89±0.23 as shown in table 4 above. The standard copper chelating agent thiourea was marginally higher than the extract Senna alata. Senna alata chelation of iron is concentration dependent also that is from 0.1 – 1 mg/ml concentration of Senna alata the percentage chelation of iron increases from 19.82±1.879 – 85.19±1.63 as shown in table 4 above. The standard iron chelating agent EDTA was slightly higher than the extract Senna alata.

Table 1: Showing Results of Total Phenol, Flavonoid and Total Antioxidantin Sennaalata

Values are mean±S.D n = 3,GAE= Gallic Acid Equivalent, QAE= Quercetin equivalent, AAE= Ascorbic Acid Equivalent

Table 2: Showing results of Nitric oxide andDPPH scavenging in Sennaalata

Values are mean±S.D n = 3

Table 3: Hydroxyl radical scavenging in Sennaalata extract

Values are mean±S.D n = 3

The findings of this investigation indicated that methanolic extract of Senna alata contains phytochemicals, that are radical scavenging and metal chelating properties which are present in different quantities with respect to the different phytocompounds.

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