Compounds isolation and antioxidant activity of Faidherbia albida fruit extract

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1 International Journal of Chemistry Studies ISSN: X Impact Factor: RJIF. Volume ; Issue ; March 0; Page No. 0 Compounds isolation and antioxidant activity of Faidherbia albida fruit extract Marwa M Mohammed, Ahmed A Ali, Ezzeldin K Desoky, Lourin G Gobraeil Assistant Lecturer at Pharmacognosy Department, Faculty of Pharmacy, Assiut University, Assiut, Egypt,, Department of Pharmacognosy, Faculty of Pharmacy, Assiut University, Assiut, Egypt Abstract Five flavonoidal compounds were successively isolated and identified from the ethanolic extract of the fruits of Faidherbia albida. Two of them were previously isolated from the leaves of Faidherbia albida, such as Rhamnocitrin (F) and Quercetin (F), the other three are firstly reported for isolation from the fruit, and named Dihydrokaempferol (F), Luteolin (F) and Rutin (F). The structures were identified and confirmed through different spectroscopic methods including NMR, CNMR and UV spectroscopy, in addition to comparison with authentic samples. Antioxidant activity was determined by the DPP method revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially the total ethanolic extract, chloroform and ethyl acetate fractions of the fruits. Keywords: Acacia, Faidherbia albida, flavonoids, dihyroflavonols, antioxidant activity Introduction Acacia (Mill.) is the largest genus in the Leguminosae with approximately 00 species [, ]. It is represented in Egypt by ten species; which are widely distributed in various phytogeographical regions of Egypt, where they are immensely useful as sources of food, fodder, firewood and as a source of natural products such as gum exudates []. Acacia sp. have many purposes as being valuable wood for industries, decorations, sources for gum, tannin, perfumes, ink, protein, paint and to prepare disinfectant for microorganisms and hand washes []. The trees of Acacia albida Delile are indigenous to Africa [] and are considered a prominent feature in the flora of Nile valley and the Eastern Desert []. Reviewing the available literature, Faidherbia albida (Del.) A. Chev. few studies were carried on the chemistry of this species and that provoked this chemical study of the plant fruits which is demonstrated by isolation and identification of the main bioactive constituents, as well as evaluation of the antioxidant activity of the different fruit extracts. Material and Methods Equipment s and chemicals NMR, CNMR measured using JEL xford Y00 (00 Mz for NMR and 00 Mz for CNMR), UV spectra were recorded in methanol on Ultrospec 000, UV VIS spectrometer, Pharmacia Biotech, Cambridge, England, Silica gel (700 mesh, EMerck, Germany) and Sephadex L0 (00 mm mesh size, EMerck) for column chromatography, TLC Silica gel G 0 F precoated plates (E Merck, Germany), The solvents used in this work include, n hexane, dichloromethane, ethyl acetate, ethanol and methanol. Also, CD D and DMSd have been used in the NMR spectral analysis using TMS as internal standard, the solvent systems used for TLC analysis include: dichloromethanemethanol (9: v/v (sys )), (90:0 v/v (sys )) and (0:0 v/v (sys)). DPP (Diphenylpicrylhydrazine) was purchased from SigmaAldrich Chemicals Co. Germany and Quercetin, Rhamnocitrin luteolin and Rutin as authentic was purchased from ElNasr Pharmaceutical and Chemical Co., Egypt) (Adwic). The plant material Fresh fruits of Faidherbia albida (Del.) A. Chev. (Acacia albida (Del.)) was collected during the fruiting stage in the period of September to December 0 from the fields of Komombo garden of medicinal plant, Aswan, Egypt. The plant was kindly identified and authenticated by Prof. Dr. kotb Amer, Botany Department, Faculty of Science, Assiut University. Extraction and isolation The airdried powdered fruit (.00 Kg) were extracted till exhaustion with ethanol 70% by maceration at room temperature. The ethanolic extracts were combined together and concentrated under reduced pressure to give. g residue (.9%) which was suspended in distilled water (00 ml), transferred to a separating funnel and extracted with successive portions of nhexane ( L), chloroform ( L) and ethyl acetate ( L). Then concentrated under reduced pressure to give the corresponding fractions; nhexane. g (0.% w/w), chloroform. g (.% w/w), ethyl acetate g (.% w/w) and the remained aqueous extract was g (7.07% w/w). (. g) of the chloroform fraction was slurried with g of silica gel, dried, powdered and transferred to the top of column packed with silica gel (0g, 0 cm). Elution was performed initially with C Cl followed by gradient systems of C Cl Me. Similar fractions were combined together and concentrated under reduced pressure where three groups

2 (FCI to FCIII) were obtained. The residue of Group FCI (. g) was dissolved in the least amount of C Cl, slurried with g of silica gel, dried and then inserted on the top of a silica gel column (0 g, 00 x cm). The column was initially eluted with C Cl followed by C Cl Me gradient systems. The subfractions eluted with C Cl Me (90:0) were collected together and subjected to further separation and purification by sephadex L0 column chromatography using 00% Me as eluent to obtain pure compounds F ( mg) and F (0 mg). ( g) of the ethyl acetate fraction was slurried with 0 g of silica gel, dried, powdered and transferred to the top of column packed with silica gel (00g, 0 cm). Elution was performed initially with C Cl followed by gradient systems of C Cl Me where five groups (FEI to FEV) were obtained. The residue of Group FEII (. g) was dissolved in the least amount of C Cl, slurried with 7. g of silica gel, dried and then inserted on the top of a silica gel column (00 g, 00 x cm) which was initially eluted with C Cl followed by C Cl Me gradient systems.the subfractions eluted with C Cl Me (90:0) were collected together and subjected to further separation and purification by sephadex L0 column chromatography using 00% Me as eluent to obtain pure compounds F (7 mg) and F ( mg). The residue of Group FEIII (00 mg) was rechromatographed on sephadex L0 column using 00% Me as eluent to obtain pure compound F (9 mg). DPP Radical Scavenging Activity (DPP assay) Antioxidant activity was determined by the DPP method []. The method is based on the reduction of alcoholic DPP solutions at 7 nm in the presence of a hydrogen donating antioxidant (A) due to the formation of the nonradical from DPP by the reaction: The actual decrease in absorption induced by the test extract or compound was calculated by subtracting that of the control. The concentration of DPP was kept at 00 μm in Me. The radical scavenging activity was measured by spectrophotometric method. Mix ml of methanolic solutions of total extract and the fractions: nhexane, chloroform, ethyl acetate and aqueous fractions of fruits (0.0, 0., 0., 0., mg/ml) with ml of methanolic solution of DPP (00µM). Similarly ml methanolic solutions of quercetin is added to ml DPP and used as a positive control. A mixture of ml of methanol and ml of methanolic solution of DPP (00 µm) served as control. After mixing, all the solutions were incubated in dark for 0 minutes and absorbance was measured at 7 nm. The experiments were performed in triplicate and percent scavenging activity was calculated as follows: Results: Five flavonoidal compounds were successively isolated and identified from the ethanolic extract of the fruits of Faidherbia albida. Two of them were previously isolated from the leaves of Faidherbia albida, such as (F) and (F), the other three are firstly reported for isolation from the fruit (F), (F) and (F). Compound F: obtained as yellow amorphous powder. R f 0. with sys. By cochromatography with an authentic sample which showed the same R f value and colour reaction, compound F was identified as Kaempferol 7methy ether (Rhamnocitrin). Compound F: obtained as yellow amorphous powder. R f 0.0 with sys. UV (Me): λ max 9, 9sh; +NaMe: 7; +AlCl : ; +AlCl /Cl: ; +NaAc: ; +NaAc/ B : 9 nm; The NMR and DEPTQ C NMR spectral data of compound F (CD D, 00 Mz) were listed in Tables, and illustrated in Figs.,. From the previously mentioned physical, chemical, chromatographic studies as well as by comparison of its spectral data (UV, NMR and DEPTQ CNMR) with those reported in the literature [], compound F was identified as Dihydrokaempferol (Aromadendrin). Compound F: obtained as yellow amorphous powder. R f 0. with sys. UV (Me): λ max, ; +NaMe: 7, 0; +AlCl : 7, ; +AlCl /Cl: 7, 7; +NaAc: 9, 0; +NaAc/ B : 9, nm; The NMR and DEPT Q CNMR spectral data of compound F (CD D, 00 Mz) were listed in Tables, and illustrated in Figs.,. From the previously mentioned physical, chemical, chromatographic studies as well as by comparison of the spectral data (UV, NMR and DEPTQ CNMR) with those reported in the literature [7] in addition to cochromatography with an authentic sample of luteolin, compound F was identified as Luteolin Compound F: obtained as yellow amorphous powder. R f 0. with sys. By cochromatography with an authentic sample which showed the same R f value and colour reaction, compound F was identified as Quercetin. Compound F: obtained as yellow amorphous powder. R f 0.7 with sys. UV (Me): λ max, ; +NaMe: 7, 0; +AlCl : 9, 7; +AlCl /Cl: 79, 70; +NaAc: 9, 0; +NaAc/ B :, 7 nm; The NMR spectral data of compound F (DMSd,00 Mz) were listed in Table and illustrated in Fig.. From the previously mentioned physical, chemical, chromatographic studies as well as by comparison of the spectral data (UV, NMR) with those reported in the literature [] in adition to cochromatography with an authentic sample of quercetinrutinoside (Rutin), compound F was identified as Quercetin rutinoside (Rutin).

3 7 9 0 ' ' Rhamnocitrin (F) ' ' ' ' ' ' Aromadendrin (F) ' ' ' ' ' ' ' ' ' ' Table : NMR spectral data of compound F (CDD, 00 Mz) Chemical shift (δ) ppm No. of protons (d) (d) (br.s) (br.s) (d) (d) Coupling constant (z).. Assignment ',' ',' Table : DEPTQ CNMR spectral data of compound F (CDD, 00 Mz) Carbon Type of Reported data δc (ppm) No. carbon (DMSd) C.9.0 C C C.0. C C 7..9 C C..7 0 C ' C ',' C ',' C.. ' C Luteolin (F) ' ' ' ' ' ' ' ' ' ' ' ' '' Quercetin (F) '' ''' ''' Table : NMR spectral data of compound F (CDD, 00 Mz): Chemical shift Integration and Coupling constant Assignment (δ) ppm (Multiplicity) (z) 7. (s) ' 7.9 (s) '.9 (d). '. (s). (br.s). (br.s) Table : DEPTQ CNMR spectral data of compound F (CDD, 00 Mz) Carbon No. Type of carbon δc (ppm) Reported data [7] C.. C C..7 C.00. C C.9. C C C ' C..0 ' C.7. ' C.7. ' C ' C.. ' C.9 9. Quercetinrutinoside (F) 7

4 Table : NMR spectral data of compound F (DMSd,00 Mz) Chemical shift (δ) ppm Integration and (Multiplicity) (br. s) (d) (dd) (d) (br.s) (br.s) (d) (s) 9 (m) (d) Coupling constant (z), 7.. Assignment ' ' ' '' "' other sugar protons C Fig. : NMR spectrum of compound F (CDD, 00 Mz) Fig. : DEPTQ CNMR spectrum of compound F (CDD, 00 Mz)

5 Fig. : DEPTQ CNMR spectrum of compound F (CDD, 00 Mz) Fig. : NMR spectrum of compound F (DMSd,00 Mz) Antioxidant activity The results of the antioxidant activity of different extracts and fractions were shown in Table and Figure. Table : Antioxidant activity of the different extracts and fractions of Faidherbia albida fruits Extracts / Concentrations Antioxidant % mg 0. mg 0. mg 0. mg 0.0mg DPP (Blank) Quercetin (Reference) Total Et extract nexane fr Chloroform fr Ethyl acetate fr Aqueous fr

6 7. Wahab A, Begum S, Ayub A, Mahmood I, Mahmood T, Ahmad A, et al. Luteolin and kaempferol from Cassia alata, antimicrobial and antioxidant activity of its methanolic extracts. FUUAST Journal of Biology. 0; ():.. Mabry TJ, Kagan J, Rösler. NMR spectra of trimethylsilyl ethers of flavonoid glycosides. Phytochemistry, 9; ():77. Fig. : Chart for the antioxidant activity of the different extracts of Faidherbia albida fruits Discussion The listed results in table, revealed that all the tested extracts and fractions exhibited strong antioxidant activity especially the total ethanolic extract, chloroform and ethyl acetate fractions of the fruits. Conclusion Five flavonoidal compounds were isolated and identified from the fruits extracts of Faidherbia albida by different spectroscopic methods, including dihydroflavonol, flavonoidal aglycons and glycoside.the strong antioxidant activity is probably due to the presence of various flavonoidal compounds. Acknowledgement I am greatly indebted to Dr. Alhossin Saber Ali amad, researcher in tropical fruit department, Faculty of Science, Aswan University and manager of horticultural research institute of Komombo garden of medicinal plant, Aswan, Egypt. For his great help and for his continuous efforts in providing me with the plant. References. Waly NM, Emad M. Taxonomical Studies of Some Acacia spp. Growing in Saudi Arabia. Bull Environ Pharmacol Life Sci, 0; :.. AlGohary I, Mohamed A. Seed morphology of Acacia in Egypt and its taxonomic significance. International Journal of Agriculture and Biology (Pakistan) Mahmoud MF, Alrumman SA, esham AEL. Biological activities of some Acacia spp.(fabaceae) against new clinical isolates identified by ribosomal RNA genebased phylogenetic analysis. Pakistan journal of pharmaceutical sciences. 0, 9().. Wood P. editor the botany and distribution of Faidherbia albida. Faidherbia albida in the West African semiarid Tropicsʼ: Workshop Proceedings ICRISAT Niamey Niger, 99.. Assimopoulou A, Sinakos Z, Papageorgiou V. Radical scavenging activity of Crocus sativus L. extract and its bioactive constituents. Phytotherapy Research, 00; 9(): Xu J, Li X, Zhang P, Li ZL, Wang Y. Antiinflammatory constituents from the roots of smilax bockii warb. Archives of pharmacal research. 00; ():99. 0