Screening of Antioxidant and Antimicrobial Properties of the Syzygium jambos L.
Mst. Marium Begum2, Majidul Haque1, Md. Reyad-ul-Ferdous5, Moynul Hasan3, Hasan Tarek3, Md. Noor-A-Alam3, Md. Belal Hossain3, Md. Nazir Uddin3, Taslima Begum4, Choudhury Mahmood Hasan1, *
1Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Dhaka, Dhaka-1000, Bangladesh
2Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Dhaka, Dhaka-1000, Bangladesh
3Department of Pharmacy, Dhaka International University, Dhaka-1213, Bangladesh
4Department of Pharmacy, Primeasia University, Dhaka-1213, Bangladesh
5Department of Pharmaceutical Sciences, North South University, Dhaka-1229, Bangladesh
To cite this article:
Mst. Marium Begum, Majidul Haque, Md. Reyad-ul-Ferdous, Moynul Hasan, Hasan Tarek, Md. Noor-A-Alam, Md. Belal Hossain, Md. Nazir Uddin, Taslima Begum, Choudhury Mahmood Hasan. Screening of Antioxidant and Antimicrobial Properties of the Syzygium jambos L. American Journal of BioScience. Special Issue: Pharmacological and Phytochemicals Investigation. Vol. 3, No. 2-1, 2015, pp. 23-26. doi: 10.11648/j.ajbio.s.2015030201.15
Abstract: Syzygium jambos (L.) Alstone belonging to the Myrtaceae family have been investigated for evaluation of their biological activities namely antioxidant and antimicrobial activity. The n-hexane, carbon tetrachloride, chloroform, aqueous soluble fractions of methanolic extract as well as crude methanolic extract of stem barks of Syzygium jambos were evaluated for their free radical scavenging activity. The methanolic extract and aqueous soluble fractions of stem barks of Syzygium jambos exhibited significant antioxidant activity with the IC50 value of 36.36 mg/ml and 44.744µg/ml respectively whereas chloroform, carbon tetrachloride and hexane soluble fraction of stem barks exhibited mild antioxidant activity with the IC50 value 191.018, 257.102, 414.79 mg/ml respectively. The crude extract, along with n-hexane, carbon tetrachloride and chloroform partitionates of the crude extract of Syzygium jambos were screened for their antimicrobial activity against a wide range of both gram-positive and gram-negative bacteria by the disc diffusion method. The results obtained were compared with that of a standard antibiotic, ciprofloxacin. All the fractions of Syzygium jambos exhibited mild activity against most of the test organism.
Keywords: Syzygium jambos, Medicinal Plant, Identification, Anti-oxidant, Antimicrobial Activity
In the plant kingdom there is a remedy for every disease 1 . Two hundred and fifty years ago, there were few or no synthetic medicines. The plants were the main source of drugs for the world's population. Today, 75% of the world's population, the poor 3/4ths, still relies on those plants and other tools of traditional medicine 2. Plants have provided a source of inspiration for novel drug compounds, as plant derived medicines have made large contributions to human health and well-being 3.
The number of higher plant species (angiosperms and gymnosperms) on this planet is estimated at 250,0004, with a lower level at 215,000 5 and an upper level as high as 500,000 6,7. Of these, only about 6% have been screened for biologic activity, and a reported 15% have been evaluated phytochemically8. Chemical diversity of secondary plant metabolites that results from plant evolution may be equal or superior to that found in synthetic combinatorial chemical libraries. Success in natural products research is conditioned by a careful plant selection, based on various criteria such as chemotaxonomic data, ethnomedical information, field observations or even random collection. One main strategy in the isolation of new leads consists of the so-called bioactivity-guided isolation, in which pharmacological or biological assays are used to target the isolation of bioactive compounds9.
The work described in this dissertation is an attempt to isolate and characterize the chemical constituents of medicinal plants, viz., Syzygium jambos (Fam. Myrtaceae) and to evaluate the possible cytotoxic profiles of the crude extracts
2. Materials and Method
2.1. Plant Material and Extract Preparation
Collection and preparation of the plant (Syzygium jambos) material: Plant sample of Syzygium jambos were collected from Gazipur, Bangladesh and was identified by an expert taxonomist of Botany Department, University of Dhaka (plant reference no. is DUSH7179). The stem barks were separated, cut into small pieces, sun dried for several days followed by oven dried for 24 hours at 40° C to facilitate grinding and finally crushed into course powder.
Extraction and fractionation: About 200gram of powdered stem barks in methanol for two weeks with occasional shaking. The mixture was filtered, concentrated at 39˚C to have a concentrated crude extract. 5gram of the extract was subjected to solvent-solvent partition for investigation of the biological activities and the remaining amount was used for chemical investigation. The concentrated methanol extract (5 g) was fractionated by modified Kupchan method 10,11 and the resultant partitionates i.e., petroleum ether, carbon tetrachloride, chloroform and aqueous soluble materials were used for different biological screenings.
2.2. Antioxidant Activity of the Purified Crude Extract of S. jambos
The free radical scavenging activity of the plant extractives was determined on the stable radical produced by 1,1-diphenyl-2-picrylhydrazyl (DPPH)12 2.0 ml of a methanol solution of the sample (extractives/ control) at different concentration (500μg/ml to 0.977μg/ml) were mixed with 3.0 ml of a DPPH methanol solution (20 μg/ml). After 30 min reaction period at room temperature in dark place the absorbance was measured at 517 nm against methanol as blank by UV spetrophotometer.
Inhibition of free radical DPPH in percent (I%) was calculated as follows:
(I%) = (1 – Asample/Ablank) X 100
Where Ablank is the absorbance of the control reaction (containing all reagents except the test material).
Extract concentration providing 50% inhibition (IC50) was calculated from the graph plotted inhibition percentage against extract concentration.
2.3. Antimicrobial Activity of the Purified Crude Extract of S. jambos
The antimicrobial activity of the extractives was determined by the disc diffusion method11 against 5 gram positive bacteria, 8 gram negative bacteria and 4 fungi. The organisms were collected as pure cultures from the Institute of Nutrition and Food Sciences (INFS). The in vitro antimicrobial study was designed to investigate the antibacterial as well as antifungal spectrum of the crude extracts by observing the growth response. Minimum inhibitory concentration (MIC) required to kill the susceptible microbial strain is used to determine and to evaluate the extracts as potential source of antibiotics. But in the present experiment MIC was not studied as antimicrobial activity of the two plant extracts was found as moderate to mild.
3. Results and Discussion
In this investigation, MESSJ showed the highest free radical scavenging activity with an IC50 value of 36.36μg/ml for the stem barks of S. jambos (Fig-1). At the same time the AQSF also exhibited strong antioxidant potential having IC50 value 44.744μg/ml and CTCSF and CLFSF also revealed moderate scavenging activity having IC50 values 257.102 μg/ml and 191.018μg/ml respectively. HSF revealed week scavenging activity having IC₅₀ value 414.79µg/ml.
The Methanolic extract of whole plant of S. jambos (MESSJ) and different partitionates i.e. hexane (HSF), carbon tetrachloride (CTCSF), and chloroform (CLFSF) soluble partitionate of the methanolic extract of whole plant of S. jambos were subjected to antimicrobial screening with a concentration of 400 mg/disc in every case. The results are given in the Table-1.
All the fractions showed no zone of inhibition .The plant S. jambos have significant anti microbial action against all bacteria and fungi.
|Test microorganisms||Diameter of zone of inhibition (mm)|
|Gram positive bacteria|
|Gram negative bacteria|
The chloroform soluble fraction and the carbon tetrachloride soluble fraction of the stem bark of S. jambos exhibited mild to moderate antimicrobial activity. Methanolic extract of stem barks and the chloroform soluble fraction of this plant showed significant free radical scavenging activity. In addition, the crude methanolic extract of stem barks, the chloroform partitionate, and carbon tetrachloride of the crude extract of the plant gave better cytotoxic effect. In conclusion, considering the potential bioactivity, this plant can be studied extensively to find out their unexplored efficacy and to rationalize their use as traditional medicine.
ME= Methanolic extract; PESF= Pet-ether soluble fraction; CTCSF= Carbon tetrachloride soluble fraction; CSF =Chloroform soluble fraction; AQSF =Aqueous soluble fraction of the methanolic extract of S. jambos.