Printer Friendly
The Free Library
23,375,127 articles and books


Morinda lucida: antioxidant and reducing activities of crude methanolic stem bark extract.

Introduction

Reactive oxygen species occur in tissues participating in potentially deleterious reactions controlled by a system of enzymatic and non-enzymatic antioxidants which eliminate pro- oxidants and scavenge scav·enge  
v. scav·enged, scav·eng·ing, scav·eng·es

v.tr.
1. To search through for salvageable material: scavenged the garbage cans for food scraps.

2.
 free radicals, Paolo et al (1991). Once radicals form they can either react with another radical or another molecule by various interactions, Okezie (1996). The rate and selectivity of reactions of this type occurring depends on high radical concentration, delocalization of the single electron of the radical (thus increasing its lifetime) and the absence of weak bonds in any other molecule present with which the radical could interact, Bensasson et al (1993), Weiss (1986, 1944). Polyphenolic compounds are secondary plant metabolites found in numerous plant species (Deshpande et al., 1984). Polyphenolic compounds have been shown to possess antimutagenic, anticarcinogenic, antiglycemic and antioxidative beneficial properties (Mendel, 1997). Phenolic phe·no·lic
adj.
Of, relating to, containing, or derived from phenol.

n.
Any of various synthetic thermosetting resins, obtained by the reaction of phenols with simple aldehydes and used as adhesives.
 compounds have been reported to play key antioxidant antioxidant, substance that prevents or slows the breakdown of another substance by oxygen. Synthetic and natural antioxidants are used to slow the deterioration of gasoline and rubber, and such antioxidants as vitamin C (ascorbic acid), butylated hydroxytoluene  roles, especially using the mechanism of delocalization of the single electron of the radical, Swallow (1953), Mendel (1997). They may produce their beneficial effects by scavenging free radicals (Gil et al., 2000).

Morinda lucida known as Oruwo in the South-western part of Nigeria is a medium--sized tree at maturity. Stem bark infusion is used as an antimalarial antimalarial /an·ti·ma·lar·i·al/ (-mah-lar´e-al) therapeutically effective against malaria, or an agent with this quality.

an·ti·ma·lar·i·al
adj.
Preventing or relieving the symptoms of malaria.
 and antidiabetic (Burkill, 1985; 1997). Antimalarial activity (Tona et al., 1999; Agomo et al. 1992; Asuzu and Chineme, 1990; Makinde and Obih, 1985; Koumaglo et al. 1992), anti-Salmonella typhi activity (Akinyemi et al., 2005), effect on contractility contractility /con·trac·til·i·ty/ (kon?trak-til´i-te) capacity for becoming shorter in response to a suitable stimulus.

contractility

a capacity for becoming short in response to suitable stimulus.
 of isolated uterine smooth muscle of pregnant and non-pregnant mice (Elias et al., 2007), toxicity and mutagenic mutagenic

inducing genetic mutation.
 studies (Sowemimo et al., 2007; Akinboro and Bakare, 2007; Raji et al., 2005) and anti-diabetic property (Olajide et al., 1999) of Morinda lucida lucida extracts have all been reported.

We report here on the evaluation of the antioxidant activity and reducing potency of the methanolic stem bark extract of Morinda lucida.

Materials and methods

Extraction of plant materials

Morinda lucida stem bark obtained taken from Amina Road, University of Ibadan The University of Ibadan is the oldest Nigerian university, and is located five miles (8 kilometres) from the centre of the major city of Ibadan in Western Nigeria. It has over 12,000 students.

The University was founded on its own site on 17 November 1948.
, Oyo state, Nigeria was identified at the Botany department of same. Stem bark sample was air dried in shade at room temperature for 14 days and powdered. 150 g of powdered stem bark was extracted in 900 ml (95% v/v) methanol for 48 hours. The crude extract was then decanted, filtered and concentrated using rotary evaporator until methanol was completely removed. Weight of concentrated dry extract was recorded for yield calculations. The solid residue obtained after rotary evaporation and drying was stored in glass vials in a refrigerator. Portions were taken from the refrigerated portions for each of the experiments and the remaining extract stored in a refrigerator.

Quantification of total phenolic compound

A modification of the method of Gow Chin Yen and Pin-Der Dur (1994) was used for quantifying total phenolic compound in plant extract. 0.1 ml stock (1 mg/ml) solution of the methanolic extract was diluted with 3.25 ml glass distilled water, 0.25 ml Folin Dennis reagent, prepared by slight modification of Official Methods of analysis of the Association of Official Analytical Chemists (1970), was added and the contents 2 3 of the test tube were mixed thoroughly. After 3 minutes, [Na.sub.2]C[O.sub.3] solution (0.5 ml, 10 g/100 ml) was added and the test tube content was finally quantified to 5 ml with distilled water. The mixture was allowed to stand for 30 minutes with intermittent shaking. Blue colour measured at 390 nm with a spectrophotometer spectrophotometer, instrument for measuring and comparing the intensities of common spectral lines in the spectra of two different sources of light. See photometry; spectroscope; spectrum.  ensued. A plot of standard curve obtained with a plot of various concentrations against corresponding absorbance absorbance /ab·sor·bance/ (-sor´bans)
1. in analytical chemistry, a measure of the light that a solution does not transmit compared to a pure solution. Symbol .

2.
 values for catechin catechin /cat·e·chin/ (kat´e-kin) an astringent principle from the heartwood of Acacia catechu (catechu) and Uncaria gambier (gambir).  using the same procedure as that used for quantifying total phenols in the plant extract above and run concurrently with the one for plant extract was made. The concentration of total phenolic compound of the methanolic extract was estimated by extrapolation on this standard curve.

Determination of reducing power of plant extract

The method of Oyaizu (1986) was used in the determination of the reducing power of plant extract. Stem bark extract (10-100 [micro]g) in 1 ml distilled water was mixed with 2.5 ml, 0.2 M, pH 6.6 phosphate buffer and 3 6 2.5 ml, 1 % Potassium Ferricyanide ([K.sub.3]Fe [(CN).sub.6), after which the mixture was incubated at 50[degrees]C for 20 minutes. 2.5 ml, 10 % Trichloroacetic acid was added to the mixture and mixture was centrifuged at 3000 rpm for 10 minutes. 2.5 ml of the supernatant was mixed with 2.5 ml distilled water and 0.5 ml, 0.1 3.% Fe[Cl.sub.3] Absorbance was measured at 700 nm using same spectrophotometer as above.

Determination of antioxidant properties of plant extract

Antioxidant activity of plant extract was determined by the method of Tafa et al., (1984), as modified by Lee et al., (1995). 3 ml aliquot aliquot (al-ee-kwoh) adj. a definite fractional share, usually applied when dividing and distributing a dead person's estate or trust assets. (See: share)  of [beta]-carotene-chloroform solution was mixed with 40 mg linoleic acid and 400 mg Tween tween  
n.
A child between middle childhood and adolesence, usually between 8 and 12 years old.



[Blend of teen1 and between.]
 40 in a conical flask. Chloroform chloroform (klôr`əfôrm) or trichloromethane (trī'klôrōmĕth`ān), CHCl3  was removed by evaporation at room temperature. 100 ml oxygenated distilled water was added to the [beta]-carotene emulsion and thoroughly mixed. 3 ml aliquot of oxygenated [beta]-carotene emulsion was mixed thoroughly with 40 [micro]l of plant extract in test tubes. The tubes were immediately placed in a water bath and incubated at 50[degrees]C. Oxidation of [beta]-carotene emulsion was o monitored spectrophotometrically at 470 nm. Absorbance was measured 10, 20, 30 and 40 minutes after addition of oxygenated water and incubation at 50[degrees]C. A control sample consisting of 40 [micro]l methanol instead of plant extract and 3 ml [beta]-carotene emulsion was also prepared.

Statistical analysis was carried out using T-test (Paired two-sample for means). Values were considered significant for [T.sub.crit 'crit A widely used short form for hematocrit *] < [T.sub.calc*] at 95% confidence limit (P < 0.05).

Results

150 g of powdered leaves yielded 7.3465 g of extract after concentration and drying with rotary evaporator. Percentage yield was calculated to be 4.9%.

A standard plot of absorbance against concentration for catechin is shown in Figure 1. The absorbance value of plant extract at 390nm was 0.368[+ or -]0.083; this absorbance value corresponds to 0.0016 mg/ml of phenolic compounds in plant extract on the standard catechin graph in Figure 1. Estimated percentage phenolic content of the extract was therefore calculated to be 80%.

[FIGURE 1 OMITTED]

[FIGURE 2 OMITTED]

An analysis of the percentage antioxidant activity exhibited by the extract is shown in Figure 3. Percentage antioxidant activity at 10 - minute interval was calculated from Table 1 using the formula:

% Antioxidant activity = ([A.sub.Extract]- [A.sub.Control])/ [A.sub.Control] x 100

[A.sub.Extract] = Absorbance in test tube containing plant extract [A.sub.Control] = Absorbance of control

Plant extract exhibited a maximum antioxidant activity of 6.33% at the concentrations used in the experiment.

The result of the experiment for the determination of the reducing power of plant extract (Figure 2) indicated that plant extract exhibited dose-dependent reducing power. Statistical analysis (T-test: paired two sample for means) of the data for antioxidant activity showed that the antioxidant activity of plant extract, compared to control was not significant (P < 0.05) within the 40-minute time frame of the experiment.

[FIGURE 3 OMITTED]

Discussion

Antioxidant activity has been directly linked to the presence of phenolic moieties present in the molecular structure of natural antioxidants. Many phytochemicals having phenolic moieties have been shown to exhibit antioxidant activity (Kahkonen et al., 1999; Frankel et al., 1995).

Estimation of the total phenolic component of extract as 80% does not imply that Morinda lucida stem bark contains phenolic components estimated from our work as 80%. Indeed, the phenolic estimation done was carried out on only the methanolic extract of the stem bark. The 80% estimated value therefore obtained, is not an approximation of the total phenolic compounds in the stem bark of Morinda lucida. [beta]-carotene-linoleic acid emulsion undergoes an oxidation pattern in which [beta]-carotene shields linoleic acid from being oxidized. However, the antioxidant activity of plant extract in the experiment is a measure of the extent of prevention of bleaching of [beta]-carotene by plant extract under comparable oxidation conditions.

Radical chain reactions could be terminated when substances exhibiting high reducing tendencies donate electrons which can react with free radicals converting them to more stable products in the process (Pin-Der, 1998). The data obtained from the experiment for determining the reducing power of plant extract (Figure 2) in which increasing absorbance values implied increased conversion of [Fe.sup.3+] to [Fe.sup.2+] implies that the extract exhibited concentration--dependent ferric ferric (fĕr`ĭk), iron in the +3 valence state.


See ferrous.
 reducing ability within the range of plant extract concentrations used for the experiment. The total phenolic content, antioxidant activity and reducing power of the extract correlated directly. The reports of Marja et al., (1999), Frankel, et al., (1995) agreed with our report.

This experiment showed that the methanolic extract of stem bark of Morinda lucida exhibits antioxidant activity. The mechanism(s) of antioxidant action of Morinda lucida remain(s) open for investigation. Further studies need to be done on the radical scavenging activity of the extracts from different parts of this plant in order to determine the specific mechanism(s) of antioxidant activity.

Acknowledgment

Our appreciation goes to Dr. Obuotor E. of the Biochemistry Department, Obafemi Awolowo University, Nigeria for his support on this project.

References

Agomo, P.U., J.C. Idigo and B.M. Afolabi, 1992. Antimalarial" medicinal plants and their impact on cell populations in various organs of mice. Afr. J. Med. Sci., 21(2): 39-46.

Akinboro, A and A.A. Bakare 2007. Cytotoxic and genotoxic genotoxic /ge·no·tox·ic/ (je´no-tok?sik) damaging to DNA: pertaining to agents known to damage DNA, thereby causing mutations, which can result in cancer.

ge·no·tox·ic
adj.
 effects of aqueous extracts of five medicinal plants on Allium allium

Any plant of a large genus (Allium) of bulbous, onion- or garlic-scented herbs of the lily family, including the onion, garlic, chive, leek, and shallot. Allium species are found in most regions of the world except the tropics and New Zealand and Australia.
 cepa Linn. J. Ethnopharmacol., 25;112(3): 470-5.

Akinyemi, K.O., U.E. Mendie, S.T. Smith, A.O. Oyefolu and A.O. Coker, 2005. Screening of some medicinal plants used in south-west Nigerian traditional medicine for anti-Salmonella typhi activity. J. Herb Pharmacother., 5(1): 45-60.

Asuzu, I.U. and C.N. Chineme, 1990. Effects of Morinda lucida leaf extract on Trypanosoma brucei brucei infection in mice. J Ethnopharmacol., 30(3): 307-13.

Bensasson, R.V., E.J. Land and T.G. Truscott, 1993. Excited states and free radicals in biology and medicine, contribution from flash photolysis and pulse radiolysis ra·di·ol·y·sis
n. pl ra·di·ol·y·ses
Molecular decomposition of a substance as a result of radiation.



ra
. Oxford University Press.

Burkill, H.M., 1997. The Useful Plants of West Tropical Africa. 2 ed. vol. 4 (Families M-R), nd Royal Botanic Gardens Royal Botanic Gardens may refer to:
  • Royal Botanic Gardens, Kew, England
  • Royal Botanic Gardens, Edinburgh, Scotland
  • Royal Botanic Gardens, Cranbourne, Victoria, Australia
  • Royal Botanic Gardens, Melbourne, Victoria, Australia
.

Burkill, H.M., 1985. The Useful Plants of West Tropical Africa. 2 ed. vol. 1 (Families A-D), Royal Botanic nd Gardens, Kew.

Deshpande, S.S., S.K. Sathe and D.K. Salunkhe, 1984. Chemistry and safety of plant polyphenols. In Nutritional and toxicological aspects of food safety; Friedman M, ed., Plenum: New York, pp: 457-495.

Elias, S.O., C.O. Ladipo, B.P. Oduwole, P.M. Emeka, P.D. Ojobor and O.A. Sofola, 2007. Morinda lucida reduces contractility of isolated uterine smooth muscle of pregnant and non-pregnant mice. Niger J. Physiol. Sci., 22(1-2): 129-34.

Frankel, E.N., 1995. Natural and Biological antioxidants in food Vitamins
  • Vitamin A (Retinol), also synthesized by the body from beta-carotene, protects dark green, yellow and orange vegetables and fruits from solar radiation damage, and is thought to play a similar role in the human body.
 and biological systems, their mechanism of action, applications and implications. Lipid Technol., pp: 77-80.

Gil, M.I., F.A. Tomas-Barberan, B. Hess-Pierce, D.M. Holcroft and A.A. Kader, 2000. Antioxidant activity of pomegranate juice and its relationship with phenolic composition and processing. J. Agric. Food Chem., 48: 4581-9.

Gow, C.Y. and D.D. Pin, 1994. Scavenging effect of methanolic extracts of peanut hulls on free radicals and active oxygen species. Journal of Agric. Food Chem., 42: 629-632.

Kahkonen, M.P., A.I. Hopia, H.J. Vourela, J. Rauha, K. Pihlaja, T.H. Kujala and M. Heinonen, 1999. Antioxidant activity plant extracts containing phenolic compounds. J. Agric. Food Chem., 47: 3954-3962.

Koumaglo, K., M. Gbeassor, O. Nikabu, C. de Souza and W. Werner, 1992. Effects of three compounds extracted from Morinda lucida on Plasmodium falciparum. Planta Med., 58(6): 533-4.

Lee, Y., L.R. Howard and B. Villalon, 1995. Flavonoids flavonoids,
n.pl common plant pigment compounds that act as antioxidants, enhance the effects of vitamin C, and strengthen connective tissue around capillaries.
 and antioxidant activity of fresh pepper (Capsicum annum). Cultivars Journal of food science, 60(3): 473-6.

Makinde, J.M. and P.O. Obih, 1985. Screening of Morinda lucida leaf extract for antimalarial action on Plasmodium berghei berghei in mice. Afr. J. Med. Med. Sci., 14(1-2): 59-63.

Mendel, F., 1997. Chemistry, biochemistry and dietary role of potato polyphenols. Journal of Agric. Food Chem., 45: 1523-40.

Okezie, I.A., 1996. Characterization of drugs as antioxidant prophylactics. Free Radical Biology & Medicine, 20(5): 675-705.

Olajide, O.A., S.O. Awe, J.M. Makinde and O. Morebise, 1999. Evaluation of the anti-diabetic property of Morinda lucida leaves in streptozotocin-diabetic rats. J Pharm Pharmacol., 51(11): 1321-4.

Oyaizu, M., 1986. Studies on products of browning reactions: Antioxidative activities of products of browning reaction prepared from glucosamine glucosamine /glu·co·sa·mine/ (gloo-ko´sah-men) an amino derivative of glucose, occurring in glycosaminoglycans and a variety of complex polysaccharides such as blood group substances. . Jpn. J. Nutr., 44: 629-632.

Paolo, D.M., E.M. Michael and S. Helmut, 1991. Antioxidation defence systems: the role of carotenoids, tocopherols and thiols. American Journal of Clinical Nutrition, 53: 194s-200s.

Pin-Der, D., 1998. Antioxidant activity of burdock burdock (bûr`däk), common name of any plant of the genus Arctium of the family Asteraceae (aster family), coarse biennials indigenous to temperate Eurasia and mostly weedy in North America.  (Arctium lappa Linne): Its scavenging effect on free- radical and active oxygen. J. Amer. Oil Chemists' Soc., 75(4): 455-461.

Raji, Y., O.S. Akinsomisoye and T.M. Salman, 2005. Antispermatogenic activity of Morinda lucida extract in male rats. Asian J Androl., 7(4): 405-10.

Sowemimo, A.A., F.A. Fakoya, I. Awopetu, O.R. Omobuwajo and S.A. Adesanya, 2007. Toxicity and mutagenic activity of some selected Nigerian plants. J. Ethnopharmacol., 113(3): 427-32.

Swallow, A.J., 1953. The radiation chemistry of ethanol and diphosphopyridine nucleotide and its bearing on dehydrogenase dehydrogenase /de·hy·dro·gen·ase/ (de-hi´dro-jen-as?) an enzyme that catalyzes the transfer of hydrogen or electrons from a donor, oxidizing it, to an acceptor, reducing it.

de·hy·dro·gen·ase
n.
 action. Biochemical Journal, 54: 253-257.

Tafa, M.S., F.E. Miller and D.E. Pratt, 1984. China seeds as a source of natural lipid antioxidants. J. Amer. Oil Chemists'. Soc., 81: 928-931.

Tona, L., N.P. Ngimbi, M. Tsakala, K. K"http://www.ncbi.nlm.nih.gov/ sites/entrez? Db=pubmed & Cmd=Search &Term=%22Mesia% 20K%22% 5BAuthor% 5D&itool= EntrezSystem2. Pentrez. Pubmed. Pubmed_ResultsPanel.Pubmed_RVAbstract"Mesia, K. Cimanga, S. Apers, T. De Bruyne, L. Pieters, J. Totte, A.J. Vlietinck, 1999. Antimalarial activity of 20 crude extracts from nine African medicinal plants used in Kinshasa, Congo.J. Ethnopharmacol. 68(1-3):193-203.

Weiss, J., 1944. Radiochemistry of aqueous solutions. Nature, 153: 748-750.

Weiss, S.J., 1986. Oxygen, ischemia and inflammation. Acta Physiol. Scand., 548(S): 9-37.

Corresponding Author: O.E. Ogunlana, Department of Biological Science, Covenant University, Canaan land, 10 Idi Iroko Iroko can refer to:
  • iroko (hardwood)
  • Telfairia occidentalis, vine grown for food
 road, Ota, Ogun state, Nigeria. E.mail: seyio2001@yahoo.com, eseyio@gmail.com

(1) O.E. Ogunlana, (1) Olubanke Ogunlana and (2) O.E. Farombi

(1) Department of Biological Science, Covenant University, Canaan land, 10 Idi Iroko road, Ota, Ogun state, Nigeria. (2) Department of Biochemistry, University of Ibadan, Oyo state, Nigeria.

(1) O.E. Ogunlana, (1) Olubanke Ogunlana and (2) O.E. Farombi, Morinda Lucida: Antioxidant and Reducing Activities of Crude Methanolic Stem Bark Extract, Adv. in Nat. Appl. Sci., 2(2): 49-54, 2008
Table 1: Antioxidant lucida extract

                       Absorbance (470nm) *

Time
(minutes)              Morinda lucida         Control

0                      0.727 [+ or -] 0.030   0.690 [+ or -] 0.000

10                     0.717 [+ or -] 0.034   0.682 [+ or -] 0.002

20                     0.715 [+ or -] 0.035   0.676 [+ or -] 0.001

30                     0.707 [+ or -] 0.031   0.668 [+ or -] 0.004

40                     0.705 [+ or -] 0.029   0.663 [+ or -] 0.004

* The values above are presented as mean [+ or -] standard
deviation of three replicate analysis
COPYRIGHT 2008 American-Eurasian Network for Scientific Information
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2008 Gale, Cengage Learning. All rights reserved.

 Reader Opinion

Title:

Comment:



 

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:Original Article
Author:Ogunlana, O.E.; Ogunlana, Olubanke; Farombi, O.E.
Publication:Advances in Natural and Applied Sciences
Article Type:Report
Date:May 1, 2008
Words:2562
Previous Article:Synergistic effect of temperature of acetone extraction of Piper guineense on maize weevil (Stitophylus zea mays) by mixture experimental design.
Next Article:Effects of arbuscular mycorrhizal fungi, phosphorus and water stress on quantity and quality characteristics of coriander.
Topics:

Terms of use | Copyright © 2014 Farlex, Inc. | Feedback | For webmasters