Phytochemical and biological investigations of extracts from the roots of Cocos nucifera L. (Arecaceae) and Carica papaya L. (Caricaceae), two plants used in traditional medicine

Abstract

Cocos nucifera L. (Arecaceae) and Carica papaya L. (Caricaceae) are two plants used to treat several human pathologies such as oxidative stress and inflammatory diseases. The aim of this study is to assess anti-inflammatory activity, antioxidant activity and acute oral toxicity, of aqueous and methanolic extracts from C. nucifera L. and C. papaya L. using appropriate experimental models. The acute oral toxicity test of extracts on mice was evaluated using Economic Cooperation and Development (OECD) guidelines 423. The capacity of extracts to inhibit key inflammation enzymes such as 15-lipoxygenase, phospholipase A 2 , cyclooxygenases 1 and 2 was evaluated in vitro. The antioxidant activity was assessed in vitro using four methods (inhibition of lipid peroxidation, FRAP, DPPH and ABTS tests). The phytochemical screening showed the presence of sterols and triterpenes, saponins, flavonoids, phenolics and tannins. Methanolic extract from C. nucifera exhibited higher values of 855.06 ± 1.71 mg GAE/ g, 418.22 ± 1.92 mg CE / g, 19.31 ± 0.6 mg GAE / g, 20.6 ± 0.36 mg QE / g dry extract respectively for phenolics, condensed tannins, hydrolysable tannins and flavonoid content. The extracts demonstrated antioxidant capacity, potential to inhibit pro-inflammatory enzymes and a lethal dose (LD 50 ) was estimated to 5000 mg/kg b.w. The results of this study constitute a solid scientific basis that can justify the traditional uses of these plants.

Phytochemical Screening by High-Performance Thin-Layer Chromatography, Antioxidant Activities and Acute Toxicity of Trunk Barks Extracts of <i>Lannea velutina</i> A. Rich

“…The plates were heated for 3 to 5 minutes on the plate heater at 110˚C. The examination was then conducted under UV light at 366 nm [19].…”

“…After derivatization, the plaque was dried for 5 minutes in a fume hood. Under white light, tannins become visible [19].…”

“…After thirty minutes in the dark and at 37˚C, the absorbance of the resulting blue hue was measured using a SHIMADZU UV-Vis spectrophotometerat 760 nm. Using the calibration curve equation 2 19.532 0.0236, 0.9999…”

“…Each measurement was conducted twice (n = 3). The aluminum trichloride method was used to evaluate trunk bark extracts' total flavonoid content (TFC), using quercetin as a reference [19]. A calibration curve is made from concentrations ranging from 0.001 to 0.5 mg/mL of a quercetin solution.…”

“…Each measurement was conducted twice (n = 3). The method described by Wendkouni et al ( 2021) is slightly modified [19]. 0.5 mL of each appropriately diluted sample or standard to 3 mL of vanillin solution (4 percent w/v in methanol) and 1.5 mL of concentrated HCl.…”