




































Asian Review of Environmental 

and Earth Sciences 
ISSN: 2313-8173 
Vol. 1, No. 2, 35-38, 2014 

http://www.asianonlinejournals.com/index.php/AREES 

 
 

 

 

 

 

35 

 

Preliminary Phytochemical, Antimicrobial and Proximate 

Analysis of Tender Leaves of Psidium guajava L in Jos, 

Plateau State, Nigeria 
 

Egga, E.S.
1
 --- Adeyanju, O.

2
 --- Agyeno, O.E.

3
 

 

1,2
Department of Chemistry, University of Jos, P.M.B 2084, Jos, Plateau State, Nigeria 

3
Department of Plant Science Technology, University of Jos, Jos, Plateau State, Nigeria 

 

Abstract 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
This work is licensed under a Creative Commons Attribution 3.0 License 

Asian Online Journal Publishing Group 

 

1. Introduction 
Guavas are plants in the myrtle family (Myrtacease). Common names are guava (English), gioba (Hausa), goifa 

(Yoruba), gova (Igbo), guayaba (Spanish), goyave (French), goeajaaba (Dutch), [1]. A native of tropical America, it 

is now planted as a fruit tree in West Africa. The seeds are distributed by man, and animals, (mainly monkey and 

birds) and are cultivated throughout the tropics. A small tree of about 6- 8m high, bark is grayish brown, hard or very 

rough and resistant to termites. The fruits are up to 4 inches long, fleshy, globosely, ovoid or pear-shaped; generally 

yellowish or white when ripe. They contain a mass of small seeds embedded in the endocarp, though some are 

seedless or nearly so. It is said to be higher in vitamin C than citrus – 80mg of vitamin C in 100g of fruit and also 

contains an appreciable amount of vitamin A [1]. The seeds are numerous, flattened and kidney-shaped. The plant is 

angiospermic and dicotyledonous. Leaves are up to 4.5 inches long, opposite, elliptic/ellipsoidal and the veins are 

prominent on the lower surface. The tender leaves are a lighter shade of green than the matured leaves and are curly 

and unfurling. The leaves of Psidium guajava are aromatic when crushed. The flowers are white, singly borne on 

short stalks in leaf axis, sepals 4, and petals 5. Leaves are scented and contain 6% of fixed oil, 0.365% of a cineol-

based essence, 3.15% resin, 8.5% tannins and other metabolites. [1]. The main components of the essential oil are 

pinene, β-pinene, limonene, β-bisobolene, caryophyllene oxide, β-copanene, quercetin and curcumene [2]. The 

essential oil from the leaves has also been shown to contain nerolidol, β-sitosterol, ursolic and guayavolic acids have 

also been identified [3].  

Leaves are particularly rich in flavonoids and distinctly rich in quercetin [4]. Much of the leaves therapeutic 

activity is attributed to the flavonoids, they demonstrate great antibacterial activity [5]. Quercetin (fig 1) is thought to 

contribute to the antidiarrhoeal effect of Psidium guajava leaves. It is able to relax intestinal smooth muscle and 

inhibit bowel contraction [6]. 

The leaf methanolic extract also showed in vitro antimicrobial activity against Escherichia coli, Salmonella 

typhi, Staphylococcus aureus, Proteus mirabilis and Shigella dysenteria [3]. The effectiveness of the leaf extract 

against Staphylococcus aureus and a strong antimicrobial action have been reported  on Gram-positive and Gram-

negative organism [7]. The flavone derivatives isolated were reported to inhibit the growth of Staphylococcus aureus 

in a dilution of 1:1000 [5]. The leaves of guava tree in decoction are recommended for gastroenteritis, chronic 

diarrhea etc. the young leaves and shoots are used for dysentery and diarrhea [8]. It has been reported that the 

Phytochemical screening, proximate, chromatographic analyses and the antimicrobial activities of 

tender leaves of Psidium guajava of the family Myrtaceae, were carried out. The phytochemical 

screening revealed the presence of all metabolites and compounds tested for such as flavonoids, 

tannins, reducing sugar,  terpenes, saponins, anthraquinones and alkaloids. The proximate analysis 

gave a moisture content of 3.67%, ash value of 3.295%, acid insoluble ash of 0.25%, alcohol soluble 

extractive value of 21.34%and water extractive value of 3.54 %. The antimicrobial screening of 

methanol extract showed activity against the tested organisms. The antimicrobial screening of hexane 

and ethyl acetate also showed activity against the tested organisms. The result indicated that the 

leaves had a potential antimicrobial activity and was concentration dependent. The chromatographic 

analysis of the extracts showed presence of variety of compounds. This therefore, supports the 

traditional medical use of Psidium guajava. 
 
Keywords: Antimicrobial, Phytochemical ,  Proximate analysis, Psidium guajava, Chromatographic analysis,  Jos. 

http://creativecommons.org/licenses/by/3.0/


Asian Review of Environmental and Earth Sciences, 2014, 1(2): 35-38 

 

 

 

36 

 

quercetin present can inhibit the intestinal movement and reduce capillary permeability in the abdominal cavity and 

this may explain the antidiarrheal mechanism of Psidium guajava extract [8]. In addition, other flavonoids and 

triterpenes in guava leaves e.g Quaijavar in (fig 2) show antispasmodic activity [9]. Guava leaves also have 

antioxidant properties which are attributed to the polyphenols in the leaves. 

 

 
 

 
 

Tender leaves are chewed to bring relief in tooth ache (analgesic) in Ghana [10]. They are chewed for stomach 

ache and piles [10]. When boiled with lemon grass (Cymbopogon citrates), an adjuvant, the decoction is used to cure 

cough. This decoction is also taken in Senegal for tracheobronchitis [10]. 

The active principles of many drug found in plants are secondary metabolites [4]. Therefore, basic 

phytochemical investigation of its extracts for major phyto-constituents is also vital. In the present study the extracts 

of Psidium guajava were screened for phytochemical constituents, antimicrobial activity and proximate analysis.    

 

2. Materials and Methods 
Plants used for this study were collected from Jos metropolis, Plateau  State, Nigeria. The  identity of plant 

materials was confirmed and authenticated at the Herbarium of the Department of  Plant Science  Technology, 

University of Jos. 

 

2.1. Preparation of Plant Extracts 
The plant material was dried at room temperature and then powdered using a grinder. The powdered sample 

(100g) was subjected to soxhlet extraction using 300ml of each of the solvents (methanol, hexane and ethyl acetate). 

The resulting extracts were concentrated on a hot water bath and kept for further investigation. 

 

2.2. Phytochemical Screening 
Phytochemical screening for major constituents was undertaken using standard qualitative methods [11]. The 

extracts were screened for the presence of glycosides, alkaloids, tannins, flavonoids, saponins, anthraquinones and 

terpenes. 

 

2.3. Test Organisms 
Standard strains of S. aureous, S. pyogenes, Bacillus subtilis, Candida albicans and Pseudomonas aeruginosa 

were obtained from the Department of Medical Microbiology, Jos University Teaching Hospital, Jos, Nigeria. 

 

2.4. Antimicrobial Screening  
MIC of the ethanolic and aqueous extract of Psidium guajave which showed the highest antibacterial activity in 

the disc diffusion assay were determined based on broth dilution technique with a standard method [12]. Inoculation 

of microorganisms were prepared from 12 hours broth cultures. Stock solutions of extracts (4000µg/ml) were diluted 

with nutrients broth cultures. Stock solutions of extracts (4000µg/ml) were diluted with nutrient broth in serial 

tenfold dilutions using nutrient broth to make dilution ranging from 250µg/ml to 4000µg/ml and inoculated with 

0.2ml of the test microorganisms. The inoculated tubes were then incubated at 37
0
c for 24hours and were inspected 

for non-turbidity. The lowest concentration of the extract which prevented visible growth was noted and recorded as 

the minimum inhibitory concentration (MIC). 

 

2.5. Proximate Analysis 
Analysis of tender leaves of Psidium guajava for moisture content, total ash, acid insoluble ash, alcohol 

extractive value and water extractive value using a standard method by Trease and Evans [13] was carried out.  

 

 



Asian Review of Environmental and Earth Sciences, 2014, 1(2): 35-38 

 

 

 

37 

 

Table-1. Phytochemical screening of methanol, hexane and ethyl acetate extracts   of tender leaves of Psidium 

guajava 

 Methanol 

extract 

Hexane extract Ethyl acetate extract 

Flavonoid ++ + - 

Tannins +++ ++ - 

Reducing sugar + + + 

Terpenes ++ + - 

Saponnins + ++ + 

Anthraquinones +++ ++ + 

Alkaloid + ++ - 
                                     +++ = High concentration; ++ = moderate concentration; + = low conc.; - = absent 

 
Table-2. Proximate analysis of tender leaves of Psidium guajava 

Moisture content 3.67% 

Total ash 3.29% 

Acid insoluble ash 0.25% 

Alcohol extractive value 21.34% 

Water extractive value 3.54% 

 
Table-3. RF values for 70% methanol, hexane and ethyl acetate extracts 

Spots 70% 

Methanol 

Hexane Ethyl acetate 70% 

methanol 

Hexane Ethyl 

acetate 

1 0.8167 0.51 0.35 0.7142 0.58 0.4761 

2 0.95 0.816 0.533 0.8571 0.827 0.6507 

3 - 0.933 0.8167 0.9523 0.931 0.7619 

4 - - 0.883 - - 0.8730 

5 - - 0.95 - - 0.9047 

6 - - - - - 0.9523 

7 - - - - - - 

 
Table-4. Minimum Inhibitory Concentration (MIC) of the tender leaves of Psidium guajava (methanol extract) Against 

tested microorganisms 

Test organism Concentration µg/ml 

 250µg/ml 500µg/ml 1000µg/ml 2000µg/ml 4000µg/ml 

Pseudomonas 

aeruginosa 

- - 0+ + + 

Bacillus subtilis - 0+ + + + 

Candida albicans - - 0+ + + 

Streptococcus 

pyogenes 

- 0+ + + + 

Staphylococcus 

aureus 

- - 0+ + + 

                  O+ = minimum inhibitory concentration; + = inhibition; - = No inhibition (turbidity) 

 
Table-5. Minimum Inhibitory Concentration (MIC) of the tender leaves of Psidium guajava (hexane extract) against tested 

microorganisms 

Test organism Concentration µg/ml 

 250µg/ml 500µg/ml 1000µg/ml 2000µg/ml 4000µg/ml 

Pseudomonas 

aeruginosa 

- - 0+ + + 

Bacillus subtilis - 0+ + + + 

Candida albicans - - 0+ + + 

Streptococcus 

pyogenes 

- 0+ + + + 

Staphylococcus 

aureus 

- - 0+ + + 

                 O+ = minimum inhibitory concentration; + = inhibition; - = No inhibition (turbidity) 

 
Table-6. Minimum Inhibitory Concentration (MIC) of the tender leaves of Psidium guajava (ethyl acetate extract) against 

tested microorganisms 

Test organism Concentration µg/ml 

 250µg/ml 500µg/ml 1000µg/ml 2000µg/ml 4000µg/ml 

Pseudomonas 

aeruginusa 

- 0+ + + + 

Bacillus subtilis - - 0+ + + 

Candida albicans - - 0+ + + 

Streptococcus 

pyogenes 

- - 0+ + + 

Staphylococcus 

aureus 

- - 0+ + + 

                      O+ = minimum inhibitory concentration; + = inhibition; - = No inhibition (turbidity) 

 



Asian Review of Environmental and Earth Sciences, 2014, 1(2): 35-38 

 

 

 

38 

 

3. Result 
The results of the phytochemical screening, proximate analysis, antimicrobial tests for the methanol, hexane and 

ethyl acetate are presented in Tables 1-6. 
 

4. Dicussion 
Phytochemical screening (Table 1) revealed the presence of flavonoid, tannins, reducing sugar, terpenes, 

saponins, anthraquinones and alkaloid. The chemical constituents present in the extracts have some therapeutic 

values. Tannins are plant metabolites well known for their antimicrobial properties [14]. Flavonoids have both 

antifungal and antibacterial activities. They possess anti-inflamatory activity [3, 15]. Flavonoid, terpenes and 

alkaloid are known to have antimicrobial and bactericidal properties against several [11]. 

In the antimicrobial studies, the majority of the organisms were more sensitive to methanolic extract. According 

to Trease and Evans [13], the anti-bacterial activity and inhibitory effect of plant extracts may be due to the presence 

of secondary metabolites. 

In Table 4, the methanolic extract of tender leaves of P. guajava was active against the entire microorganisms. It 

has MIC value of 500μg/ml against Bacillus subtilis and Streptococcus pyogenes, 100 μg/ml against Pseudomonas 

aeruginosa, Candida albicans, and Staphylococcus aureus. 

These findings are consistent with Etuk, et al. [16] who reported that the bark extract of P. gaujava had 

antidiarrheal activity in vitro. Previous reports have demonstrated the antidiarrheal activity of tannins [17], 

Flavonoids [18] and saponins [9]. In Table 2, the low moisture content (3.67%) implies that the plant can be stored 

for a long time and not affected by microbial attack. The ash content (3.29%) buttresses the claim that it is highly 

organic and medicinal. In Table 3, the components of the extract separated on the plates showed that variety of 

compounds are present in the extracts. 

 

5. Conclusion 
The result of this experiment showed that tender leaves of P. guajava may have some valuable anti-microbial 

activities. This property tends to support the traditional medicinal stage in the treatment of bacterial infections. The 

result justified the use of the plant in the treatment of diseases of microbial origin in herbal medicine. 

 

6. Contribution/ Originality of This Study 
This study contributes to the existing literature and the scientific justification of the medicinal potential of this 

plant. The findings in this research validate its use among the low income people such as farmers, villagers and 

native communities. It is also likely to establish a scientific bases and proof for its potential use in folk medicine for 

the treatment of infectious diseases produced by common pathogenic microorganisms. 

 

Reference 
[1] H. M. Burkhill, The useful plants of West tropical Africa vol. 4. London: The British Printing Company Limited, 1997. 

[2] M. B. Zakaria and M. A. Mohd, "Traditional malay medicinal plants," Journal of Science Forum, vol. 1, pp. 34-36, 1994. 

[3] M. M. Iwu, "Plant flavonoids in biology and medicine," in Proceeding of 4th Annual Conference of the Nigeria Society for 

Pharmacology. University of Nigeria Nusukka, 1984. 

[4] A. Abok, A. A. Adeyemi, and I. A. Jegede, "Spectrophtometric estimation of anthraquinone content and antimicrobial potentral of 

extracts of some cassia species used in herbal medicine in Ibadan Nigeria," Sci. Forum., vol. 3, pp. 57-63, 2000. 

[5] B. Oliver-Bever, Medicinal plants in tropical West Africa. Cambridge University Press, 1986. 

[6] G. D. Pamplona-Roger, Encyclopedia of medicinal plants. Toledo, Spain: Arts Graficas, 2004. 

[7] S. O. Gnan and M. T. Demello, "Inhibition of staphyloccus aureus by aqueous goiaba extracts," Journal of Ethno Pharmacology, vol. 

7, pp. 112-117, 1999. 

[8] Ticzon, Ticzon herbal medicine encyclopedia. Phillpines: Romeo R. Ticzon Company Publishing, 1997. 

[9] A. L. Otsusi, A. Foriers, A. Vercrysee, and A. Vanb Zeebrock, "Invitro antimicrobial activity of size medicinal plant traditionally 

used for the treatment of dysentery and diarrhea in democratic republic of Congo (DRC) Phytomdeine," Journal of Phytomedicine, 

vol. 7, pp. 162-172, 2000. 

[10] F. R. Irvine, Woody plants of Ghana. London: Oxford University Press, 1961. 

[11] H. Usman, F. I. Abdulrahman, and A. A. Ladan, "Phytochemical and antimicrobial evaluation of tribulus terrestris. L 

Zygophylaceae) growing in Nigeria Res," J. of BIOSC. Medwel J., vol. 2, pp. 244-247, 2007. 

[12] Y. S. Krivoshein, Handbook on microbiology. Russia: Mic Publisher, 1989. 

[13] G. E. Trease and W. C. Evans, Pharmacognosy, 11th ed. London: Baillier Tirdal, 1978. 

[14] R. Tschesche, Advances in the chemistry of anti-biotres substances from higher plants; pharmacognosy international congress. 

Heidelberg New York: Verlog, Berlin, 1971. 

[15] A. O. Ogundaini, From greens into medicine taking a lead from nature Inaugurad lecture Series No.176. Nigeria: O.A.U Press Ltd, 

Ile-Ife, 2005. 

[16] E. U. Etuk, M. Ugwah, N., O. P. Ajagbonna, and P. A. Onyeyili, "Ethnobotonical survey and preliminary evaluation of medicinal 

plants with antidiarrhoea properties in Sokoto, Nigeria," Journal of Science Forum, vol. 2, pp. 80-85, 2009. 

[17] P. K. Mukherjee, J. B. R. S. Das, Palm, and P. M. Saha, "Antidirraheal evaluation of nelumbe nucifera rhizome extract," India J. 

Pharmacol., vol. 22, pp. 262-268, 1995. 

[18] J. Galvez, A. ZarZuelo, M. E. Crespo, M. D. Lorente, M. A. Ocete, and Z. J. Jmene, "Antidiarroeal activity of evphobia extract and 

isolation of active flavonoid content," Planta Medica., vol. 59, pp. 333-336, 1993. 

 
 

 

 

 

 

 

Views and opinions expressed in this article are the views and opinions of the authors, Asian Review of Environmental and Earth Sciences shall not be 

responsible or answerable for any loss, damage or liability etc. caused in relation to/arising out of the use of the content. 

 


