Subscribe Now Subscribe Today
Research Article
 

Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare



Johnson O. Oladele, Boyede D. Olowookere, Mutiat O. Bamigboye, Oyedotun M. Oyeleke, Kehinde E. Alabi, Opeyemi O. Oladele and Israel O. Oyewole
 
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail
ABSTRACT

Background and Objective: Reports from robust scientific and clinical studies have proven the efficacies of phytochemicals, antioxidants and vitamins in the amelioration and treatment of complications arising from excessive oxidative stress. This study was designed to carry out the phytochemistry of the natural compounds present in ethanol leaf extract of Talinum triangulare and to assess the in vitro antioxidant activities of the extract. Materials and Methods: Chemical composition with secondary metabolites profiling in the extract were carried out using standard procedure and Fourier-Transform Infrared Spectroscopy (FTIR) spectrophotometry and in vitro, antioxidant activities of the extract were assessed by evaluating hydrogen peroxide, hydroxyl radical, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities and ferric reducing antioxidant power methods. Results: The phytochemical analysis of the extract showed the presence of coumarins, terpenoids, flavonoids, alkaloids, phenols, saponins, quinones, vitamin C, glycosides and betacyanin. Further, the FTIR analysis showed the presence of aliphatic bromo, aromatic fluoro, aromatic primary amine, trimethyl, methyl alkenyl, methylene, dimeric OH, alkanes, alkenes and aromatic ring groups. In vitro, antioxidant assays results also reveal that the extract free radical scavenging abilities are significantly high when compared with standard antioxidants used (gallic and ascorbic acids). Conclusion: Taken together, the results from this study suggest the extract as a source of natural antioxidants that could have considerable therapeutic relevance in preventing and inhibiting the progression of diseases associated with oxidative stress.

Services
Related Articles in ASCI
Search in Google Scholar
View Citation
Report Citation

 
  How to cite this article:

Johnson O. Oladele, Boyede D. Olowookere, Mutiat O. Bamigboye, Oyedotun M. Oyeleke, Kehinde E. Alabi, Opeyemi O. Oladele and Israel O. Oyewole, 2021. Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare. Current Research in Chemistry, 13: 26-34.

DOI: 10.3923/crc.2021.26.34

URL: https://scialert.net/abstract/?doi=crc.2021.26.34
 
Copyright: © 2021. This is an open access article distributed under the terms of the creative commons attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

INTRODUCTION

Plants like herbs have been extensively used for different kinds of nutritional and medicinal purposes. Medicinal herbs have been used for decades before the establishment of traditional medicine. Secondary metabolites of these medicinal plants, which are also known as phytochemicals are naturally occurring active plant compounds that have prospective disease ameliorating capabilities. The well-known fact is that phytochemicals may be effective in fighting or preventing diseases due to their antioxidant effects1. Different studies on various plants extracts show they exerted their pharmacological activity through multiple targets, an important factor that influences the therapeutic efficacy of bioactive agents present in these plants2.

Reports from robust scientific and clinical studies have proven the efficacies of phytochemicals, antioxidants and vitamins in the amelioration and treatment of complications arising from excessive oxidative stress3-5. Previous studies from our laboratory have shown that some plant extracts and products are capable of mitigating hormonal disruption, alteration of steroidogenic pathway and testicular oxidative damage6. Some of these phytochemicals such as flavonoids from medicinal plants have been reported being safe while showing other pharmacological actions, in addition to their antioxidant properties7, including anti-carcinogenicity, anti-mutagenicity, anti-bacterial, anti-viral and anti-inflammatory effects8.

Talinum triangulare is a medicinal plant popularly known as waterleaf and originated from tropical Central Africa, which is now being cultivated in other parts of the continents for its valuable properties. It is a fleshy-leaved perennial plant grown widely in humid tropical countries as a leaf vegetable9. The plant has eaten in almost every home in Africa for its nutritious value, has also been valued for its incredible antioxidant properties and has been connected with the management of diseases like measles, cancer, obesity, diabetes, jaundice and stroke10. Talinum triangulare has found to have special features, which make it strive in various soil types, temperatures and moisture levels and grows even during the dry season.

This study investigated the phytochemical constituent present in ethanol leaf extract of Talinum triangulare and in vitro antioxidant activities of the extract.

MATERIALS AND METHODS

Chemicals and reagents: Folin-Ciocalteu’s reagent, HCl, methanol, gallic acid, H2SO4, Na2CO3, aluminium chloride, potassium acetate, potassium persulfate, sodium nitroprusside, hydrogen peroxide, sulphanilic acid, glacial acetic acid, naphthyl ethylenediamine dichloride, NADH were all purchased from Merck, USA. DPPH (1,1-diphenyl-1,2-picryl hydrazyl), TPTZ (2,4,6,-tripyridyl-s-triazine), Ferrozine, Deoxyribose Sigma (St. Louis, MO, USA). Trichloroacetic acid (TCA), L-Ascorbic acid and all other chemicals and reagents used were of analytical grade.

Plants collection: Fresh samples of Talinum triangulare leaves were harvested in a garden at Obada area of Kings University, Ode-Omu, Osun State, Nigeria. The plant was identified and deposited at the herbarium of the Department of Biological Sciences, Osun State University, Osogbo, Osun State, Nigeria. This research was conducted from November, 2019-February, 2020.

Preparation of extract: The fresh samples of Talinum triangulare leaves were air-dried at room temperature to constant weight after which they were pulverized into powder using an electrical blender. The powdered leaf materials were cold-macerated with six volumes of 80% ethanol for 72 hrs. The crude extract was obtained by filtration followed by evaporation of the solvent in a rotatory evaporator. The paste was then freeze-dried.

Qualitative phytochemical analysis: Qualitative screening of ethanol leaf extract of Talinum triangulare was carried out to identify the active phytochemicals like phenols, flavonoids, saponins, tannins, coumarins, alkaloids, terpenoids, anthraquinones and anthocyanins.

Test for anthraquinones: About 2% diluted hydrochloric acid was added to 1 mg of ethanol leaf extract of Talinum triangulare. The appearance of red colour was interpreted as the presence of anthraquinone11.

Test for phenols: Assessment of phenol was determined following the method described by Oladele11. Briefly, 2 mL of distilled water was added to 1 mg of ethanol leaf extract of Talinum triangulare and 10% ferric chloride was added to it. The confirmation sign of phenols presence was the formation of green or blue colour.

Test for coumarins: Total 1 mg of ethanol leaf extract of Talinum triangulare was reacted with 1 mL of 10% sodium hydroxide. The formation of yellow colour in the test sample was an indication of the presence of coumarins11.

Test for flavonoids
Alkaline reagent test: This test was carried out using the procedure described by Unuigbe et al.12. About 1 mL of 2 N sodium hydroxide was added to 1 mg of ethanol leaf extract of Talinum triangulare. The formation of yellow colour was interpreted as the presence of flavonoids.

FeCl3 test: Few drops of FeCl3 solution were added in 1 mL of the extract. The existence of flavonoids was indicated by the formation of blackish-red precipitate13.

Test for saponins
Froth formation with distilled water: Two mg of the extract was mixed with 2 mL of distilled water in the test tube. After this accumulation, the test sample was mixed vigorously for almost 15 min. The formation of a soapy layer indicated the presence of saponins in test samples11.

Test for alkaloids
Mayer’s test: About 2 mL of the extract was reacted with concentrated HCl and a special reagent named Mayer’s reagent. Formation of white precipitates or appearance of green colour was an indication of alkaloids presence12.

Hager’s test: Few drops of Hager’s (Saturated picric acid solution) reagent were added to 2 mL of the extract. The formation of bright yellow precipitates specified the manifestation of alkaloids13.

Test for anthocyanin and betacyanins: Total 1 mg of the extract was taken in the test tube and followed by the addition of 2 mL of 1 N sodium hydroxide. The test sample was boiled at 100°C for about 10 min. Anthocyanin presence was indicated by the formation of bluish-green colour while yellow colour formation was indicative of betacyanin presence12.

Test for sterols
Salkowski test: Total 2 mL of the extract, 5 mL of chloroform was added and then 1 mL concentrated H2SO4 was carefully dispensed along the walls of the tube. The appearance of reddish colour in the lower layer indicated the existence of sterols13.

Test for vitamin C: Dinitrophenylhydrazine was dissolved in concentrated sulphuric acid and allowed to react with 1 mL of the extract. The appearance of yellow precipitates indicated the presence of vitamin C in test samples.

Test for proteins
Xanthoproteic test: According to this procedure, 1 mL of extract was treated with few drops of concentrated nitric acid. The presence of proteins in test samples was indicated by the formation of yellow colour.

Biuret test: About 0.5 mg of extract was taken and an equal volume of sodium hydroxide solution (40%) was added to it. After that few drops of 1%, CuSO4 solution was added. The appearance of violet colour in test samples manifested protein presence.

Emulsion test with olive oil: Total 1 mL of extract was poured in test tubes followed by the addition of 5-6 drops of olive oil and shaken vigorously to form a stable froth. The formation of an emulsion was the confirmatory sign of saponin presence13.

Test for tannins
FeCl3 test: Total 1 mg of extract, 2 mL of 5% ferric chloride was added. The appearance of greenish-black or dark blue colour was the indication of tannins presence12.

Alkaline reagent test: Total of 2 mL of 1 N NaOH solution was added in 2 mL of the extract. The appearance of yellow to red colour showed the presence of tannins13.

Test for triterpenoids: About 1 mL of Liebermann-Burchard Reagent (concentrated H2SO4+acetic anhydride) was added in 1.5 mL extract. Triterpenoids were determined by the appearance of bluish-green colour in the test samples.

Test for terpenoids: About 0.5 mg of extract was taken in the test tube and 2 mL of each chloroform and concentrated sulphuric acid was added to plant samples. The presence of terpenoids was indicated by the formation of a brown layer in the middle of the other two layers12.

Test for glycosides (Keller Kiliani’s test): Total 1 mL of extract, 1 mL glacial acetic acid was added and left to cool down. After cooling two drops of FeCl3 were added and 2 mL of concentrated H2SO4 along the walls of the test tube was dispensed carefully. The development of a reddish-brown coloured ring at the intersection of two layers indicated the presence of glycosides13.

Test for oils and resins (filter paper test): Extract was applied on filter paper and checked for the establishment of transparent appearance, which was a positive sign for the presence of oils and resins in respective test samples.

Test for steroids and phytosteroids: A total of 1 mL of chloroform and few drops of concentrated sulphuric acid were added to 1 mL of the extract. The formation of brown coloured ring indicated steroids presence whereas the appearance of a bluish-brown coloured ring marked the presence of phytosteroids in the test samples.

Test for phlobatannins: Total 1 mL of each plant sample, few drops of 10% ammonia solution were added. The formation of pink-coloured precipitates showed the existence of phlobatannins in samples.

Test for quinones: A volume of 1 mL of extract was allowed to react with 1 mL concentrated sulphuric acid. The appearance of red colour manifested the occurrence of quinones.

FT-IR spectroscopic analysis: Fourier Transform Infrared Spectrophotometer (FTIR) is currently the best technique and equipment to evaluate types of chemical bonds/functional groups present in natural products or phytochemicals. The wavelength of light absorbed is the salient feature of the chemical bonds seen in the annotated spectrum. By interpreting the infrared absorption spectrum, the chemical bonds in a compound can be determined. Dried powder of ethanol solvent extract of Talinum triangulare was used for FTIR analysis. A volume of 10 mg of the dried extract powder was encapsulated in 100 mg of KBr pellet, to prepare translucent sample discs. The powdered sample of the extract was loaded in FTIR spectroscope (Shimadzu, Japan), with a Scan range from 400-4000 cm–1 with a resolution of 4 cm–1.

Reducing power assay: The reducing power of various extracts was based on Fe (III) to Fe (II) transformation according to the method of Oyaizu14. The Fe (II) was monitored by measuring the formation of Perl’s Prussian blue at 700 nm, using vitamin C and tannic acid as standards. The extract or standard (100-1000 μg mL–1) was mixed with phosphate buffer (pH 6.6) and potassium ferricyanide. The mixture was incubated at 50°C for 20 min. Trichloroacetic acid (2.5 mL of 10%) was added to the mixture. A portion of the resulting mixture was mixed with FeCl3 (0.5 mL of 0.1%) and the absorbance was measured at 700 nm in a spectrophotometer. Higher absorbance of the reaction mixture indicated the reductive potential of the extract.

Hydrogen peroxide scavenging assay: The ability of the extract to scavenge hydrogen peroxide was determined according to the method of Ilhami et al.15. A solution of hydrogen peroxide (40 mM) was prepared in phosphate buffer (pH 7.4). Different concentrations of plant extract were added to a hydrogen peroxide solution (0.6 mL, 40 mM). The absorbance of hydrogen peroxide at 230 nm was determined after 10 min against a blank solution containing phosphate buffer without hydrogen peroxide. The percentage inhibition of hydrogen peroxide of extracts and standard compounds (Vitamin C and Tannic acid) was calculated using the following Eq.15:

Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare

where, A0 was the absorbance of the control and A1 was the absorbance in the presence of the sample of extract and standards.

Hydroxyl radical scavenging assay: Hydroxyl radical scavenging activity of the extracts was determined by the method of Batool et al.16 with a slight modification. About 0.5 mL of extract or standard (Vitamin C and Tannic acid) at different concentration was taken in test tubes. Total 1 mL of Fe-EDTA solution (0.13% ferrous ammonium sulphate and 0.26% EDTA), 0.5 mL of 0.018% EDTA solution, 1 mL of 0.85% DMSO solution and 0.5 mL of 22% ascorbic acid were added into the test tubes. The test tubes were capped tightly and warm at 85°C for 15 min into the water bath. After incubation, the test tubes were uncapped and 0.5 mL ice-cold TCA (17.5%) was added to each of the test tubes immediately. A volume of 3 mL of Nash reagent (7.5 g of ammonium acetate, 300 μL glacial acetic acid and 200 μL acetylacetone were mixed and made up to 100 mL) was added to all the tubes and incubated at RT for 15 min. Absorbance was taken in UV-spectrophotometer at 412 nm wavelength. Percentage hydroxyl radical scavenging (% HRSA) activity was calculated using the following Eq.16:

Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare

where, A0 is the absorbance of the control and A1 is the absorbance of the extracts/standard.

DPPH-radical scavenging assay: The radical scavenging activity of plant extracts was measured as described by Mensor et al.17. The stable 2, 2 diphenyl-1-picrylhydrazyl (DPPH) radical was used for the determination of free radical scavenging activities of the extracts. A portion (1 mL) each of the different concentrations (40-2000 μg mL–1) of the extracts or standard (Vitamin C and Tannic acid) in test tubes was added to 1 mL of 1 mM DPPH in methanol. The mixtures were vortexed and then incubated in a dark chamber for 30 min after which the absorbances were measured at 517 nm against a DPPH control containing only 1 mL of methanol in place of the extract. All calculations were carried out in triplicates. The inhibition of DPPH was calculated as a percentage using the expression17:

Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare

where, I (%) is the inhibition of the DPPH free radicals in percentage, Acontrol is the absorbance of the control reaction containing all reagents except the test compound and Asample is the absorbance of the test compound.

Statistical analysis: The results were analysed using SPSS Version 12. Data were expressed as Mean±standard error of the mean (Mean±SD). The student’s t-test was employed for comparison between two sets of data while p<0.05 was considered statistically significant.

RESULTS AND DISCUSSION

In the present study, bioactive constituents that confer pharmacological and biological dynamic nature to therapeutic plants were screened and the results confirmed the existence of coumarins, terpenoids, flavonoids, alkaloids, phenols, saponins, quinones, vitamin C, glycosides and betacyanin in ethanol leaf extract of Talinum triangulare (Table 1). The therapeutic propensity of medicinal plants has been linked to the availability of their constituent phytochemicals18,19. These can be assessed by performing initial qualitative screening to ensure the presence of these phytochemicals.

Compounds belonging to the respective groups have been reported to impart various medicinal characteristics to the plants. Alkaloid exhibited promising anti-diarrheal, anti-inflammatory, anti-cancer, anti-diabetic activities and cure urinary disorders20,21. Polyphenolic compounds in plants such as tannins have been reported to have cytoprotective and therapeutic effects against haemorrhage, diarrhoea and microbial infections22. Flavonoids and phenols have a vital wide range of therapeutic activities such as anti-hypertensive, anti-rheumatism, anti-diuretic, anti-oxidant, anti-microbial and anti-cancer properties23,24. Saponins have been documented to have inhibitory effects against pests, bacteria and fungi25.

Table 1: Phytochemical constituents of ethanol leaf extract of Talinum triangulare
Phytochemicals ETT
Phenol +
Coumarins +
Saponin +
Tannin -
Anthraquinone -
Anthocyanin -
Betacyanin +
Glycosides +
Phlorotannin -
Oils and resin +
Proteins +
Quinones +
Flavonoids (alkaline reagent) +
Flavonoids (FeCl3) +
Alkaloids +
Sterols -
Vitamin C +
Sterols and phytosterols -
Triterpenoids +
Terpenoids -
+: Present, -: Absent, ETT: Ethanolic extract of T. triangulare


Table 2: FTIR spectral peak valves and functional groups obtained from ethanol leaf extract of Talinum triangulare
Peaks wavelength (cm1) Functional groups
767.69 Aliphatic bromo compounds, C-Br stretch
1122.61 Aromatic fluoro compounds
1271.13 Aromatic primary amine, CN Stretch
1311.64 Skeletal C-C vibrations
1384.94 Trimethyl or “tert-butyl” (multiple)
1448.59 Methyl C-H asym./sym. Bend
1626.05 Alkenyl C=C stretch
2852.81 Methylene C-H asym./sym. Stretch
2928.04 Methyl C-H asym./sym. Stretch
3423.76 Dimeric OH stretch

The present study results confirmed the presence of these phytochemicals in ethanol leaf extract of Talinum triangulare hence justified its usage of this plant in traditional systems of medicine and confirm its therapeutic abilities.

FTIR analysis was carried out on ethanol leaf extract of Talinum triangulare to identify the functional groups present. The result of the analysis in Table 2 and Fig. 1 showed the extract contains phytochemicals with different functional groups like aliphatic bromo, aromatic fluoro, aromatic primary amine, trimethyl, methyl alkenyl, methylene, dimeric OH, alkanes, alkenes and aromatic ring compounds, which shows peaks of 767, 1122.61, 1271.13, 1311.64, 1384.54, 1448.59, 1626.05, 2852.81, 2928.04 and 3423.76 cm–1. This result further corroborates the presence of phytochemicals in ethanol leaf extract of Talinum triangulare as listed in Table 1.

To assess and verify the presence of antioxidant capabilities in ethanol leaf extract of Talinum triangulare, a variety of antioxidant assays have been established with varying mechanics and kinetics. These assays enquire the extract in diverse ways before certifying it as an antioxidant.

Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare
Fig. 1:
FTIR spectrum of ethanol leaf extract of Talinum triangulare


Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare
Fig. 2:
Reducing power activities of different concentrations of ethanol leaf extract of Talinum triangulare

So, to appraise the antioxidant capacity of extract a series of antioxidant assays were conducted.

The result in Fig. 2, revealed the reducing power of different concentrations of ethanol leaf extract of Talinum triangulare compared with ascorbic acid and tannic acid. The yellow colouration of the testing mixture changes to green depending on the reducing power of the test specimen. The presence of the reducing agents in the sample solution causes the reduction of the Fe3+/ferricyanide complex to the ferrous form. Thus, the ferrous ion can be monitored by absorbance measurement at 700 nm. The reducing properties have been documented to exert antioxidant action by donating a hydrogen atom to break the free radical chain26. Increasing absorbance at 700 nm indicates an increase in reducing ability. The ethanol leaf extract of Talinum triangulare used in the study shows significant reducing power when compared with ascorbic acid and gallic acid used as standard antioxidants.

The carcinogenic and mutagenic ability of free radicals is due to the direct interactions of hydroxyl radicals with DNA molecules, which play a critical role in the carcinogenesis pathway (cancer formation). Hydroxyl radicals can cause damage to almost every biological cell and can be generated during biotransformation reaction in the body.

Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare
Fig. 3:
Hydroxyl radical (OH) scavenging activities of different concentrations of ethanol leaf extract of Talinum triangulare


Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare
Fig. 4:
Hydrogen peroxide (H2O2) scavenging activities of different concentrations of ethanol leaf extract of Talinum triangulare

Superoxide radical was converted by superoxide dismutase to hydrogen peroxide, which could subsequently produce extremely reactive hydroxyl radicals in the presence of divalent metal ions, such as iron and copper27. Results in Fig. 3, showed that the ethanol leaf extract of Talinum triangulare used in the present study has significant hydroxyl radical scavenging abilities when compared with ascorbic acid and gallic acid. The hydroxyl radical detoxification may be due to the presence of polyphenols and flavonoids in the extracts.

Hydrogen peroxide scavenging activity of the various concentrations of extract used in this study was presented in Fig. 4 when compared with the standard antioxidants: Ascorbic acid and gallic acid. Hydrogen peroxide is a very weak oxidant but can become very toxic when rapidly decomposed into oxygen and water and this may produce hydroxyl radicals (•OH) that can initiate lipid peroxidation and cause DNA damage28. Hydrogen peroxide can also inhibit the activities of some enzymes by oxidising their essential thiol (-SH) groups. The extract used in this study efficiently scavenged hydrogen peroxide which may be attributed to the presence of phenolic groups that could donate electrons to hydrogen peroxide, thereby neutralising it into water.

Hydrogen donating ability is one of the indices to ascertain the antioxidant properties of phytochemicals. Radical scavenging activities are critical to prevent the damaging role of free radical in different diseases. DPPH has known to abstract labile hydrogen and the ability to scavenge the DPPH radical has related to the inhibition of lipid peroxidation29. The result in Fig. 5, shows that the extract used in this study have significant free radical scavenging activities when compared with standard antioxidants: Gallic acid and ascorbic acid.

Image for - Chemical Profiling, Phytochemical Constituents and in vitro Antioxidant Activities of Ethanol Leaf Extract of Talinum triangulare
Fig. 5:
DPPH scavenging activities of different concentrations of ethanol leaf extract of Talinum triangulare

The extract shows higher scavenging ability over gallic acid and ascorbic acid. This indicates that the extract could have a better free radical scavenging ability and inhibit lipid peroxidation more efficiently than gallic acid and ascorbic acid.

CONCLUSION

The in vitro free radical scavenging activities assays reveal that ethanol leaf extract of Talinum triangulare has significant radicals scavenging properties on hydrogen peroxide, hydroxyl radicals and DPPH radical. The presence of coumarins, terpenoids, flavonoids, alkaloids, phenols, saponins, quinones, vitamin C, glycosides and betacyanin in ethanol leaf extract of Talinum triangulare corroborated the high reducing power of the extract. Altogether, this work demonstrated that the extract possessed significant antioxidant activities over well-characterised standard antioxidants, thus, suggesting the extracts as sources of natural antioxidants that could have high therapeutic relevance in preventing or inhibiting the progression of diseases associated with oxidative stress.

SIGNIFICANCE STATEMENT

This study demonstrated the phytochemical constituents and in vitro antioxidant activities of ethanol leaf extract of Talinum triangulare. The results show the phytochemical constituents, their respective functional groups and the in vitro antioxidant activities of the extract. This study demonstrated that the extract possessed significant antioxidant activities over well-characterised standard antioxidants, thus, suggesting the extracts as sources of natural antioxidants that could have high therapeutic relevance in preventing or inhibiting the progression of diseases associated with oxidative stress.

ACKNOWLEDGMENT

The technical support of the laboratory staff of the Department of Chemical Sciences, Kings University is greatly appreciated.

REFERENCES

1:  Oladele, J.O., O.M. Oyeleke, O.T. Oladele and A.T. Oladiji, 2021. COVID-19 treatment: Investigation on the phytochemical constituents of Vernonia amygdalina as potential coronavirus-2 inhibitors. Comput. Toxicol., Vol. 18.
CrossRef  |  Direct Link  |  

2:  Akinmoladun, A.C., I.O. Saliu, B.D. Olowookere, O.B. Ojo, M.T. Olaleye, E.O. Farombi and A.A. Akindahunsi, 2017. Improvement of 2-vessel occlusion cerebral ischaemia/reperfusion-induced corticostriatal electrolyte and redox imbalance, lactic acidosis and modified acetylcholinesterase activity by kolaviron correlates with reduction in neurobehavioural deficits. Ann. Neurosci., 25: 53-62.
CrossRef  |  Direct Link  |  

3:  Oladele, J.O., O.T. Oladele, O.M. Oyeleke and A.T. Oladiji, 2021. Neurological complications in COVID-19: Implications on international health security and possible interventions of phytochemicals. Contemp. Dev. Perspect. Int. Health Secur., Vol. 2.
CrossRef  |  Direct Link  |  

4:  Marchioli, R., C. Schweiger, G. Levantesi, L. Tavazzi and F. Valagussa, 2001. Antioxidant vitamins and prevention of cardiovascular disease: Epidemiological and clinical trial data. Lipids, 36: S53-S63.
CrossRef  |  Direct Link  |  

5:  Oladele, J.O., O.I. Oyewole, O.K. Bello and O.T. Oladele, 2017. Hepatoprotective effect of aqueous extract of Telfairia occidentalis on cadmium chloride-induced oxidative stress and hepatotoxicity in rats. J. Drug Des. Med. Chem., 3: 32-36.
CrossRef  |  Direct Link  |  

6:  Oladele, J.O., O.M. Oyeleke, O.T. Oladele, O.D. Babatope and O.O. Awosanya, 2020. Nitrobenzene-induced hormonal disruption, alteration of steroidogenic pathway, and oxidative damage in rat: Protective effects of Vernonia amygdalina. Clin. Phytosci., Vol. 6.
CrossRef  |  Direct Link  |  

7:  Oladele, J.O., O.T. Oladele, A.O. Ademiluyi, O.M. Oyeleke, O.O. Awosanya and O.I. Oyewole, 2020. Chaya (Jatropha tanjorensis) leafs protect against sodium benzoate mediated renal dysfunction and hepatic damage in rats. Clin. Phytosci., Vol. 6.
CrossRef  |  Direct Link  |  

8:  Ozgová, Š., J. Heřmánek and I. Gut, 2003. Different antioxidant effects of polyphenols on lipid peroxidation and hydroxyl radicals in the NADPH-, Fe-ascorbate- and Fe-microsomal systems. Biochem. Pharmacol., 66: 1127-1137.
CrossRef  |  Direct Link  |  

9:  Swarna, J. and R. Ravindhran, 2013. In vitro organogenesis from leaf and transverse thin cell layer derived callus cultures of Talinum triangulare (Jacq.) Willd. Plant Growth Regul., 70: 79-87.
CrossRef  |  Direct Link  |  

10:  Ukpong, I.E. and J.O. Moses, 2001. Nutrient requirement for the growth of water leaf (Talinum triangulare) in Uyo Metropolis, Nigeria. Environmentalist, 21: 153-159.
CrossRef  |  Direct Link  |  

11:  Oladele, J.O., M.O. Bamigboye, B.D. Olowookere, O.M. Oyeleke, J.C. Anyim, K.S. Oladele and I.O. Oyewole, 2020. Identification of bioactive chemical constituents present in the aqueous extract of Telfairia occidentalis and its in vitro antioxidant activities. J. Nat. Ayurvedic Med., 4: 1-10.
Direct Link  |  

12:  Unuigbe, C., H. Okeri, O. Erharuyi, E. Oghenero and D. Obamedo, 2015. Phytochemical and antioxidant evaluation of Moringa oleifera (Moringaceae) leaf and seed. J. Pharm. Bioresour., 11: 51-57.
Direct Link  |  

13:  Ahmad, I.M. and A.M. Wudil, 2013. Phytochemical screening and toxicological studies of aqueous stem bark extract of Anogeissus leiocarpus in rats. Asian J. Sci. Res., 6: 781-788.
CrossRef  |  Direct Link  |  

14:  Landry, J., A. Sutton, S.T. Tafrov, R.C. Heller, J. Stebbins, L. Pillus and R. Sternglanz, 2000. The silencing protein SIR2 and its homologs are NAD-dependent protein deacetylases. Proc. Nat. Acad. Sci., 97: 5807-5811.
CrossRef  |  Direct Link  |  

15:  Gülçin, İ., H.A. Alici and M. Cesur, 2005. Determination of in vitro antioxidant and radical scavenging activities of propofol. Chem. Pharm. Bull., 53: 281-285.
CrossRef  |  Direct Link  |  

16:  Batool, R., M.R. Khan, M. Sajid, S. Ali and Z. Zahra, 2019. Estimation of phytochemical constituents and in vitro antioxidant potencies of Brachychiton populneus (Schott and Endl.) R.Br. BMC Chem. Vol. 13.
CrossRef  |  Direct Link  |  

17:  Mensor, L.L., F.S. Menezes, G.G. Leitao, A.S. Reis, T.C. dos Santos, C.S. Coube and S.G. Leitao, 2001. Screening of Brazilian plant extracts for antioxidant activity by the use of DPPH free radical method. Phytother. Res., 15: 127-130.
CrossRef  |  PubMed  |  Direct Link  |  

18:  Oyewole, O.I., J.O. Oladele and O.T. Oladele, 2017. Methanolic leaf extract of Ficus exasperata attenuates arsenate–mediated hepatic and renal oxidative stress in rats. Res. J. Health Sci., 5: 115-123.
CrossRef  |  Direct Link  |  

19:  Oyewole, O.I. and J.O. Oladele, 2017. Changes in activities of tissues enzymes in rats administered Ficus exasperata leaf extract. Int. J. Biol. Chem. Sci., 11: 378-386.
CrossRef  |  Direct Link  |  

20:  Awoyinka, A.O., I.O. Balogun and A.A. Ogunnowo, 2007. Phytochemical screening and in vitro bioactivity of Cnidoscolus aconitifolius (Euphorbiaceae). J. Med. Plant Res., 3: 63-65.

21:  Monika. J., B. Anil, B. Aakanksha and P. Priyanka 2012. Characterization and in vitro antiurolithiatic activity of cerpegin alkaloid from Ceropegia bulbosa var. Lushii root. Int. J. Drug Dev. Res., 4: 154-160.
Direct Link  |  

22:  Cai, Y., J. Zhang, N.G. Chen, Z. Shi, J. Qiu, C. He and M. Chen, 2016. Recent advances in anticancer activities and drug delivery systems of tannins. Med. Res. Rev., 37: 665-701.
CrossRef  |  Direct Link  |  

23:  Oladele, J.O., E.I. Ajayi, O.M. Oyeleke and O.T. Oladele et al., 2020. A systematic review on COVID-19 pandemic with special emphasis on curative potentials of Nigeria based medicinal plants. Heliyon, Vol. 6.
CrossRef  |  Direct Link  |  

24:  Veerachari, U. and A.K. Bopaiah, 2011. Preliminary phytochemical evaluation of the leaf extract of five cassia species. J. Chem. Pharm. Res., 3: 574-583.
Direct Link  |  

25:  Chaieb, I., 2010. Saponins as insecticides: A review. Tunisian J. Plant Protec., 5: 39-50.
Direct Link  |  

26:  Wang, J., S. Hu, S. Nie, Q. Yu and M. Xie, 2016. Reviews on mechanisms of in vitro antioxidant activity of polysaccharides. Oxid. Med. Cell. Longev., Vol. 2016.
CrossRef  |  Direct Link  |  

27:  Thorpe, G.W., M. Reodica, M.J. Davies, G. Heeren and S. Jarolim et al., 2013. Superoxide radicals have a protective role during H2O2 stress. Mol. Biol. Cell, 24: 2876-2884.
CrossRef  |  Direct Link  |  

28:  Zeghad, N., E. Ahmed, A. Belkhiri, Y.V. Heyden and K. Demeyer, 2019. Antioxidant activity of Vitis vinifera, Punica granatum, Citrus aurantium and Opuntia ficus indica fruits cultivated in Algeria. Heliyon, Vol. 5.
CrossRef  |  Direct Link  |  

29:  Kedare, S.B. and R.P. Singh, 2011. Genesis and development of DPPH method of antioxidant assay. J. Food Sci. Technol., 48: 412-422.
CrossRef  |  Direct Link  |  

©  2022 Science Alert. All Rights Reserved