Journal of
Medicinal Plants Research

  • Abbreviation: J. Med. Plants Res.
  • Language: English
  • ISSN: 1996-0875
  • DOI: 10.5897/JMPR
  • Start Year: 2007
  • Published Articles: 3704

Full Length Research Paper

Development of a rich fraction in phenolic compounds with high antioxidant and antimicrobial activity in Amburana cearensis seeds extracts

Aline Aires Aguiar
  • Aline Aires Aguiar
  • Natural Products Research Laboratory, Biodiversity and Biotechnology Post Graduate Program of the Amazon (Bionorte), Federal University of Tocantins, Palmas, Tocantins 77020-210, Brazil.
  • Google Scholar
Ilsamar Mendes Soares
  • Ilsamar Mendes Soares
  • Natural Products Research Laboratory, Biodiversity and Biotechnology Post Graduate Program of the Amazon (Bionorte), Federal University of Tocantins, Palmas, Tocantins 77020-210, Brazil.
  • Google Scholar
Poliana Guerino Marson
  • Poliana Guerino Marson
  • Faculty of Medicine, Biodiversity and Biotechnology Post Graduate Program of the Amazon (Bionorte), Federal University of Tocantins, Palmas, Tocantins 77020-210, Brazil.
  • Google Scholar
Ernane Gerre Pereira Bastos
  • Ernane Gerre Pereira Bastos
  • General and Applied Microbiology Laboratory, Biodiversity and Biotechnology Post Graduate Program of the Amazon (Bionorte), Federal University of Tocantins, Palmas, Tocantins 77020-210, Brazil.
  • Google Scholar
Sérgio Donizeti Ascêncio
  • Sérgio Donizeti Ascêncio
  • Faculty of Medicine, Natural Products Research Laboratory, Biodiversity and Biotechnology Post Graduate Program of the Amazon (Bionorte), Federal University of Tocantins, Palmas, Tocantins 77020-210, Brazil.
  • Google Scholar
Raimundo Wagner de Souza Aguiar
  • Raimundo Wagner de Souza Aguiar
  • Department of Biotechnology, Biodiversity and Biotechnology Post Graduate Program of the Amazon (Bionorte) Gurupi, Federal University of Tocantins, Tocantins 77404-970, Brazil.
  • Google Scholar

  •  Received: 22 September 2017
  •  Accepted: 23 October 2017
  •  Published: 03 November 2017


Amburana cearensis is a medicinal plant widely used in folk medicine. The purpose of this study was to identify the more appropriate extraction solvent for maximum antioxidant and antimicrobial effect. The extraction of A. cearensis seeds were carried out gradually to obtain the highest yields and constituents of the extracts using as solvent hexane, methanol, 80% alcohol and water in this sequence. Phytochemical screening showed phenolic compounds and thin layer chromatography (TLC) showed the flavonoid morin. Antioxidant activity was also evaluated by the method of scavenging the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH); rutin and ascorbic acid was used as standard; the hydro-alcoholic extract (EEA) showed an IC50 value of 17.95 μg/ml, similarly to the standards rutin and ascorbic acid, indicating high antioxidant action. The microdilution assay (MIC) showed antibacterial activity against the bacteria concentrations, values ≥0.25 mg/mL for EEA and aqueous (AEA) extracts against S. aureus, P. aeruginosa and S. flexneri. High performance liquid chromatography (HPLC) analysis of A. cearenses seed extracts revealed a high content of flavonoids and tannin compounds corroborating with TLC analysis. The extraction by exhaustion was very effective in exposing the bioactive principles of A. cearenses seeds showing their best compounds mainly in EEA extract.


Key words: Amburana cearensis, exhaustion extraction, seed, phytochemical profile, antioxidant, antimicrobial activity.


Amburana cearensis, known as umburana or cumaru is a leguminous plant of Fabaceae family, used  in  perfumery and for pharmaceutical purposes; it can be observed in practically all of America, from Peru to Argentina  (Canuto  and Silveira, 2006). Many parts of this plant are used in traditional medicine, stem bark and leaves contain phenolic compounds with anti-inflammatory and antioxidant effects (Leal et al., 2003), they are also useful in conducting several physiological disorders such as diabetes mellitus, hypertension, vascular fragility and improvement of the health of gastrointestinal tract (Scalbert et al., 2005). The seeds are used for stomach and liver diseases (Leal et al., 2008). Besides, some peptides from A. cearensis have antifungal (dos Santos et al., 2010)and antimicrobial activity (Sá et al., 2011).
The antimicrobial activity of phenolics and flavonoids are also well documented (Erdemoglu et al., 2007; Xia et al., 2011). The phenolics compounds can affect the growth and metabolism of bacteria, activating or inhibiting the microbial growth according to their constitution and concentration (Alberto et al., 2006; Nazzaro et al., 2009).
The need to find new antimicrobial substances against microorganisms presents a challenge in the treatment of infectious disease (Gonçalves and Santana, 2010).
Currently, many bacterial strains are resistant to almost all antimicrobials. The search for antibacterial properties of plant extracts has been encouraged and intensified, substances derived from plants constitute approximately 25% of medically prescribed agents in industrialized countries (Sá et al., 2011).
Several studies have demonstrated the presence of secondary metabolites and antimicrobial activity in leaves and stem bark of the A. cearensis, however, the seeds do not present similar results (Lima et al., 2013), this is already expected because the main constituents of most seeds are carbohydrates, lipids and proteins, followed by other constituents in smaller amounts such as vitamins, minerals and water (Vaclavik and Christian, 2006).  Furthermore,  the solubility of secondary compounds depends on the type of solvent used, degree of polymerization, as well as interaction with other food constituents and formation of insoluble complexes  (Naczk and Shahidi, 2004), indicating the need for further studies with this part of the plant.
Due to the widespread use of A. cearensis for medicinal purposes and the scarcity of phytochemical reports of its seeds in the literature, it has become essential to carry out its study, to discover the possible response for the therapeutic properties of A. cearensis. The aim of this study was to determine the antioxidant capacity and antimicrobial activity of A. cearensis extracts against bacteria strains. 


This study was done in  Natural  Products  Research  Laboratory  of Federal University of Tocantins (UFT), Palmas Campus, Tocantins, Brazil.
The seeds of A. cearensis were obtained from popular commerce in the city of Palmas, Tocantins, Brazil, and their authenticity recognized by EMBRAPA Herbarium, voucher (CPAP 5948). The seeds were dried in a stove at 45°C and ground using knives crusher (Start FT 50 - Fortinox). The ground seeds were stored in bottles and kept at room temperature and covered from light and humidity (Al-Marby et al., 2016).
Seed extract preparation
To prepare the extracts, 15 g of powdered seeds were extracted for 4 h using the Soxhlet apparatus (Mabiki et al., 2013). First, an extraction was performed with 80% ethanol at the boiling temperature of the solvent, resulting in the crude extract (CEA). Subsequently, another extraction was carried out using different solvents, n-hexane, methanol, 80% ethanol and water, from the lowest to the highest polarity to extract the maximum seed components.
Each solvent was used after being dried in a stove at 40°C for 24 h. The solvents were removed on a rotary evaporator at -600 mm Hg (Fisaton 804) at 45°C. They were dried in the exhaust hood and stored in an amber bottle and kept at 4°C. The hexanic, methanol, 80% ethanol, and water extracts were respectively named as, hexanic extract (HEA), methanol extract (MEA), ethanol extract (EEA), and aqueous extrac (AEA).
Phytochemical screening
To elucidate which compounds were mainly present in CEA extract, previous phytochemical analysis was achieved according to previously described methods (Matos, 2009), based on coloration/precipitation tests. This analysis was complemented by thin layer chromatography (TLC). The test was fulfilled using benzene-ethyl acetate-formic acid-methanol (60/30/10/5, v/v/v/v) as the mobile phase.
Then, dried plates have been sprayed with a 1% solution of 2-aminoethyl diphenylborinate in methanol and spray with a 0.5% ethanolic solution of polyethylene glycol (NEU/PEG reagent). Next, the plates were visualized using a darkroom viewing cabinet (SOLAB®, model SL 204) UV light at 365 nm. The retention factor (Rf) values were calculated measuring the distance reached by the extract divided by the distance of the mobile phase and compared with Rf of standards rutin, quercetin, and morin.
Determination of phenolic compounds and total flavonoid content
Total phenolic content was quantified using the Folin-Ciocalteu method as described by Amorim et al. (2008) and determined by interpolation of the absorbance of the samples and the calibration curve constructed with standard, gallic acid in methanol (y = 1.3631x + 0.0213, adjusted r2 = 0.962). The result was exposed as mg gallic acid equivalents (GAE) per gram  of  A.  cearensis  extract (mg GAE/g).
Total flavonoid content was performed using the method described by Soares et al. (2014) with few modifications and determined by using the absorbance of the samples against a calibration curve (y = 1.3336x + 0.0078, adjusted r2 = 0.9999) constructed with the rutin standard and expressed as milligrams of rutin equivalents (RE) per gram of dry extract (mg RE/g).
Evaluation of antioxidant activity
The antioxidant activity was performed by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) (Sigma-Aldrich®) assay, described by Peixoto-Sobrinho et al. (2011). Standards were used as rutin and ascorbic acid (Sigma-Aldrich®). The percentage scavenging values were calculated following the equation:
AA (%) = [(A0 - (AS - Ablank))/A0] × 100
where AA is the antioxidant activity, AS is the absorbance of the sample, Ablank is the absorbance of the blank, and A0 is the absorbance of DPPH without sample.
The IC50 value calculated indicates the concentration of a sample required to decrease the absorbance at 517 nm by 50%. The IC50 was expressed in μg/mL.
HPLC analysis
The A. cearensis extracts were analyzed by high-performance liquid chromatography (HPLC) at Scientific Instrumentation Laboratory (LABIC) UFT-Palmas, Tocantins, Brazil. The HPLC system (Shimadzu, Tokyo, Japan) consisted of a chromatograph (LC-10 Avp series) with a pump (LC-10 AD), a degasser (DGU-14A) to pump the mobile phase, rheodyne manual injector (20 μL loop) and class integrator (LC-10A), a UV-Vis (SPD - 10A) detector and a column oven (CTO 10A). The extracts and standards were prepared with methanol and filtered with Millipore membrane (0.22 μm pore size). The separation was achieved by a gradient system, using a reverse-phase Phenomenex Luna 5 mm C18 (2) (250 4.6 mm2) column with direct-connect C18 Phenomenex Security Guard Cartridges (4 3.0 mm2) filled with similar material as the main column. Mobile Phase A was 0.1% phosphoric acid in Milli-Q water and mobile phase B was 0.1% phosphoric acid in Milli-Q water/acetonitrile/methanol (54:35:11). Flow rate: 1 ml/min, temperature: 22 1C. UV detection was done at 280 nm. The standards used were gallic acid, rutin, ellagic acid, naringin, myricetin, morin, quercetin, naringenin, and kaempferol (Sigma®). The compounds were expressed in micrograms per milligram of extract (μg/mg) by correlating the area of the analyte with the calibration curve of standards built in concentrations of 4.5 to 18 μg/mL.
Bacterial strains
The American Type Culture Collection (ATCC) bacterial strains used were Staphylococcus aureus (29213), Listeria monocytogenes (35152), Escherichia coli (25922), Aeromonas species (7966), Pseudomonas aeruginosa (27853), and Shigella flexneri (700930). The strains were stored at -20°C, and sub-cultured two days before the assays.
Antimicrobial activity in broth
The minimum inhibitory concentration was determined by the microplate dilution  technique  (96   holes)   according   to  the methodology described according to the M7-A6 standard of the Manual 38 Clinical and Laboratory Standards Institute (CLSI, 2006), the most recommended method for this determination (Benfatti et al., 2010). The microplate wells were filled with 100 μL of Muller-Hinton broth medium (MHB-Micro Med), then 100 μL of extract solutions were added and a serial dilution was performed: 1000, 500, 250, 125, 62.5, 31.2, 15.6, and 7.8 μg/mL. In addition, 20 μL of the microorganism suspensions were inoculated into each well of the microplates. As a positive control, chloramphenicol was used at the same dilutions as extracts. Control of the culture medium, bacterial growth control and negative control (solvents) were also performed. The microplates were incubated in an incubator at 37°C for 24 h, all tests were performed in triplicate.
The MIC was expressed as the lowest concentration that inhibited growth, which was judged by the well. The turbidity in each well was then measured at 450 nm by using a spectrophotometer (GT - 722G). The MIC values equal to or less than 1000 μg/mL were considered active (Kuete, 2010).
Statistical analysis
The experiment was totally randomized, with three replicates per treatment. The ANOVA test was obtained using the ASSISTAT 7.6 beta program.


Phytochemical screening
Many studies have demonstrated the profuse presence of coumarin, flavonoids and tannins in stem bark and leaves of A. cearensis as responsible for pharmacological activities of this species according to the effects observed in tests pure substances (Marinho et al., 2004; Canuto, 2006); however, these phenolic compounds have not yet been well documented in seeds, this can occur because secondary metabolites link competitively for some solvents during the extraction process (Naczk and Shahidi, 2004). In this work, the sequential extraction process eliminated this interference, favoring the extraction of phenolic compounds. A similar extraction methodology was performed by Zhu et al. (2010) in a study with Portulaca oleracea L, obtaining such results. Seed extraction from A. cearensis provided 1.315 g (8.73%) hexane extract, 3.877 g (25.91%) methanolic extract, 1.009 g (6.66%) hydroethanolic extract and 0.876 g (5.33%) aqueous extract.
Analysis by thin layer chromatography (TLC)
The evaluation by TLC showed, in EEA A. cearensis seed extracts the presence of flavonoids, as evidenced by emergence of fluorescence in Rf stains EEA (Rf=75), MEA (Rf=73) and AEA (Rf=80). Characteristic for reference standards (Rutin Rf=31; Quercetin Rf=81; Morin Rf=75) (Figure 1).
Table 1 shows the total phenol, flavonoids and the evaluation of total antioxidant activity of A. cearensis seed extracts. The EEA extract presented higher phenolic and flavonoid content, this high antioxidant activity is probably due to the type of extraction performed, since the EEA is an extract practically free of interferents as fatty compounds, moreover, this extract was the only one which presented rutin in HPLC analysis (Figure 3).
Values ​​below the IC50 reflect high antioxidant activity. EEA extract values were very close to the ascorbic acid and rutin patterns (Figure 2).
HPLC analysis
The fingerprinting of A. cearensis extracts obtained by HPLC is as shown in Figure 3. The retention time of samples and the standards made possible the identification of various phenol compounds, such as: gallic acid (time 16.5 min), catechin (time 23.7 min), rutin (time 40.6 min), ellagic acid (time 41.5 min), naringin (time 43.4 min), myricetin (time 46.8 min), and morin (time 49.5 min). The substances detected in extracts are shown in Table 2.
Rutin is a powerful free radical scavenger that has a significant therapeutic potential against cancer; morin possess antibacterial activity (Pereira et al., 2015). Catechin is considered antifungal (Anand and Rai, 2016) and has shown activity against many bacteria (Shahid et al., 2016).
The HPLC data made evident that the A. cearensis seeds extracts obtained are plentiful in phenolic compounds of pharmacological importance and antioxidant significance. Different phenolic compounds appear in the different extracts, demonstrating the extraction method used was effective to elucidate the potential stored in A. cearensis seeds. EEA extract has the highest number of phenolic compounds (Table 2) corroborating with results of  DPPH  and  TLC  tests.  The not identified peaks shown in the chromatograms (Figure 3) can be phytocomponents with important biological activity and different potential. Hence, more research with A. cearensis seeds could improve the pharmacological knowledge about this plant.
Antibacterial assay
The bioassays with extracts of A. cearensis showed that EEA and AEA extratcs had activity against E. coli, P. aeruginosa, S. flexneri, L. monocytogenes and S. aureus, with MIC values ranging from 250 to 1000 µg/mL. CEA, HEA and MEA extracts had no significant effect against these microorganisms (Table 3). There is no report of antibacterial activity in A. cearensis seeds extracts prior to this work. Santos et al. (2010) have shown activity of peptide from A. cearensis seeds only against phytopathogenic fungi and yeasts and Lima et al. (2013) showed no antibacterial activity against strains of S. aureus, E. coli and P. aeruginosa with their A. cearensis extract. Catechin and naringin is present in EEA extract (Table 2), it is known that these phenolic compounds act against microorganisms (Anand and Rai, 2016), then it explains the antimicrobial activity of this extract. The standard   antibiotic   for   this   assay,    chloramphenicol, showed a broad spectrum of antibacterial activity with MIC values ranging from 7.8 to 1000 µg/mL. The MIC values for the extracts and the positive control are shown in Table 3.


This work has demonstrated that exhaustion extraction of A. cearensis seeds was effective in obtaining extracts with high quantity of phenolic compounds, separating the interferents of these compounds as lipid components and revealing high antioxidant action compared to rutin standard. The result of the antioxidant activity in this work showed that A. cearensis seeds are abundant in substances capable of scavenging free radicals and HPLC analysis exposed that these seeds are a source of compounds with pharmacological features. Moreover, the antimicrobial activity justifies its use in folk medicine for the treatment of many diseases. Hence, this data indicates A. cearensis as a new source of potential antioxidant and antimicrobial agents.


The authors have not declared any conflict of interests.


Al-Marby A, Ejike CE, Nasim MJ, Awadh-Ali NA, Al-Badani RA, Alghamdi GM, Jacob C (2016). Nematicidal and antimicrobial activities of methanol extracts of 17 plants, of importance in ethnopharmacology, obtained from the Arabian Peninsula. J. Intercult. Ethnopharmacol. 5(2):114-21.


Alberto MR, Canavosio MAR, Manca NMC (2006). Antimicrobial effect of polyphenols from apple skins on human bacterial pathogens. Electron. J. Biotechnol. 9(3):205-209.


Amorim ELC, Nascimento JE, Monteiro JM, Peixoto-Sobrinho TJS, Araújo TAS, Alburquerque UP (2008). A Simple and Accurate Procedure for the Determination of Tannin and Flavonoid Levels and Some Applications in Ethnobotany and Ethnopharmacology. Func. Ecosyst. Commun. 2(1):68-74.


Anand J, Rai N (2016). Anticandidal synergistic activity of green tea catechins, antimycotics and copper sulphate as a mean of combinational drug therapy against candidiasis. J. Mycol. Med. 27(1):33-45.


Benfatti CS, Cordova SM, Guedes A, Mogina MDA, Cordova CMM (2010). Atividade antibacteriana in vitro de extratos brutos de espécies de Eugenia sp. Rev. Pan-Amaz. Saúde 1(2):33-39.


Canuto KM, Rocha SE (2006). Constituintes químicos da casca do caule de Amburana cearensis a.c. smith Quim. Nova 29(6):1241-1243.


Erdemoglu NS, Tosun F (2007). Alkaloid profile and antimicrobial activity of Lupinus angustifolius L. alkaloid extract. Phytochem. Rev. 6:197-201.


Kuete V (2010). Potential of Cameroonian plants and derived products against microbial infections. Planta Med. 76:1479-1491.


Leal, LKAM, Nechio M, Silveira ER, Canuto KM, Fontenele JB, Ribeiro RA, Viana GSB (2003). Anti-inflammatory and smooth muscle relaxant activities of the hydroalcoholic extract and chemical constituents from Amburana cearensis A. C. Smith. Phytother. Res. 17(4):335-340.


Leal LKAM, Fonseca FN, Pereira FA, Canuto KM, Felipe CFB, Fontenele JB, Viana GSB (2008). Protective effects of amburoside A, a phenol glucoside from Amburana cearensis, against CCl4-induced in rats. Planta Med. 74(5):497-502.


Lima LR, Cavalcante RRL, Martins MCC, Parente DM, Cavalcante AAMC (2013). Avaliação da atividade antiedematogênica, antimicrobiana e mutagênica das sementes de Amburana cearensis (A. C. Smith) (Imburana-de-cheiro). Rev. Bras. Plantas Med. 15(3):415-422.


Marinho MGV, de Brito AG, Carvalho KA, Bezerra SCR, Andrade LHC, Barbosa JMF, Piuvezam MR (2004). Amburana cearensis e Cumarina Imunomodulam os níveis de anticorpos antígeno-específico em camundongos BALB/c sensibilizados com ovalbumina. Acta Farm. Bonaerense. 23(1):47-52.


Matos FJA (2009). Introdução à fitoquímica experimental. 3.ed.


Naczk M, Shahidi F (2004). Extraction and analysis of phenolics in food. J. Chromatogr. A. 1054(1-2):95-111.


Nazzaro F, Caliendo G, Arnesi G, Veronesi A, Sarzi P, Fratianni F (2009). Comparative content of some bioactive compounds in two varieties of Capsicum annuum l. sweet pepper and evaluation of their antimicrobial and mutagenic activities. J. Food Biochem. 33:852-868.


Peixoto-Sobrinho TJDS, Castro VTNA, Saraiva AM, Almeida DM, Tavares EA, Amorim ELC (2011). Phenolic content and antioxidant capacity of four Cnidoscolus species (Euphorbiaceae) used as ethnopharmacologicals in Caatinga, Brazil. Afr. J. Pharm. Pharmacol. 5(20):2310-2316.


Pereira WL, Oliveira TT, Kanashiro M, Costa MR (2015). The antiproliferative action of morin flavonoid and olive leaf extract (Olea europaea L.) against the cell line H460. Rev. Bras. Plant Med. 17(4):798-806.


Sá MCA, Peixoto RDM, Krewer CC, Almeida JRGS, Vargas AC, Costa MM (2011). Antimicrobial activity of caatinga biome ethanolic plant extracts against gram negative and positive bacteria. Rev. Bras. Ciênc. Vet. 18(2/3):62-66.


Santos PHA, Santos IS, Melo VMM, Vasconcelos IM, Carvalho AO, Gomes VM (2010). Partial characterization and antimicrobial activity of peptides from Amburana cearensis seeds against phytopathogenic fungi and yeasts. Acta Physiol. Plantarum. 32(3):597-603.


Scalbert A, Manach C, Morand C, Rémésy C., Jiménez L (2005) Dietary polyphenols and the prevention of diseases. Crit. Rev. Food Sci. 45:287-306.


Soares IM, Bastos EGP, Peixoto-Sobrinho TJDS, Alvim TC, Silveira MA, Aguiar RWS, Ascêncio SD (2014). Conteúdo fenólico e atividade antioxidante de diferentes cultivares de Ipomoea batatas (L.) lam. obtidas por melhoramento genético para produção industrial de etanol. Rev. Cienc. Farm. Básic. Appl. 35(3):479-488.


Shahid A, Ali R, Ali N, Hasan SK, Bernwal P, Afzal SM, Vafa A, Sultana S (2016). Modulatory effects of catechin hydrate against genotoxicity, oxidative stress, inflammation and apoptosis induced by benzo(a)pyrene in mice. Food Chem. Toxicol. 92:64-74.


Vaclavik V, Christian EW (2008). Essentials of Food Science Springer.


Xia DX. Wu JS, Yang Q, Zhang Y (2011). Phenolic compounds from the edible seeds extract of Chinese Mei (Prunus mume Sieb. et Zucc) and their antimicrobial activity. LWT-Food Sci. Technol. 44:347-349.


Zhu H, Wang Y, Liu Y, Xia Y, Tang T (2010). Analysis of flavonoids in Portulaca oleracea L. by UV-vis spectrophotometry with comparative study on different extraction technologies. Food Anal. Method 3(2):90-97.