Introduction

Application of medicinal plants by man for the treatment of various infection is well known since long time. A large proportion of village population worldwide depends on this. The indigenous system of medicine namely Ayurveda and Unani have been in existence from ancient times. The medicinal value of plants and herbal drug is attributed to the presence of some chemical components in them such as glycosides, resins, alkaloids, essential oils, gum, mucilage etc. 4,11,13.

From time to time study has been conducted on different medicinal plant product and their antimicrobial activity has been reported8,9,15, Antimicrobial activity of leaf extracts of medicinal plants has been studied and the antibacterial and antifungal action has been demonstrated1,8,12,14. Reports on antimicrobial activity of plant pollen extract are scanty. Recently in Turkey, antibacterial activity of Turkish pollen and propolis extracts against some common plant pathogen was conducted by EsinBasima et al., (2006) whereas SolangTeresinhaCarpes et al., of Brasil in 2007 has made studies on antibacterial activity of ethanolic pollen extracts against some pathogenic bacteria like Pseudomonas aeruginosa, Bacillus cereus, Staphylococcus aureus, Klebsiellaspp.etc Alike their work other workers have reported the therapeutic importance of pollen and propolis extracts6,7,10. In India work on evaluating antimicrobial activity of any pollen extract has no been reported yet. Therefore in the present study an attempt has been made to investigate antibacterial activity of methanolic extract of Cucurbitapepo pollen against some human pathogenic bacteria. The test bacteria in our study were S. aureus, Proteus vulgaris, Bacillus cereus and Escherichia coli.

Material and Methods

All the bacterial species viz.. S. aureus,

vulgaris, B. cereus and E. coli used for testing were obtained from Disha Institute of Bio-Technology and Research Pvt. Ltd Nagpur. Microbiological methods were used for identification of these bacteria which included studying their morphological, cultural and biochemical characteristics. Various culture media needed for the study were obtained from Hi-media Laboratory, Mumbai, Culture media, reagents and glassware used were sterilized by the recommended standard methods. Anthers of Cucurbitapepo (Cucurbitaceae) were carefully collected from the fields located near Nagpur and Bhandara and their identity was confirmed through literature. Two grams of fresh pollen powder was grounded in 8 ml methanol to get alcoholic extract. The alcoholic macerate were kept for 24 hr. at room temp.11 Macerates were centrifuged at 10,000 rpm for 15-20 min. The supernatant was filtered by using Whatmann no. 1filter paper and sterilized by bacteriological membrane filter technique. This 2.5% filter sterilized methanolic extract of C. pepo pollen was used for in vitro study.

Disc diffusion method² was employed for testing antibacterial activity of methanolic pollen extract. About 25ml Muller-Hinton Agar poured into petri plate was cooled at room temperature for setting. 0.1 ml of fresh Nutrient Broth of the test bacterial culture was surface spread on Muller-Hinton Agar. Sterile Whattmann no. 1 filter paper discs of 5 mm diameter soaked in pollen alcoholic extract were placed on the inoculated media and incubated at 37°Cfor 24hr.

Results and Discussion

Results of antibacterial activity of methanolic extract of Cucurbitapepo pollen is shown in Table 1. Out of four bacterial human pathogens tested in our study Staphylococcus aureus and Bacillus cereus have shown resistance towards the pollen extract while Esherichia coli and Proteus vulgaris have exhibited marked sensitivity.

Table 1: Antibacterial activity of methanolic pollen extract of Cucurbitapepo.

Our results thus clearly indicate the presence of antibacterial action possessed by plant pollen extract alike the extracts of plant leaves, stems roots seeds which is shown by earlier workers1,8,9,11,12,13,15. More over work done by Isla et al., (2001), Proestos et al., (2005) and Carpes et al., (2007) have revealed the antimicrobial activity in pollen extract to be associated with the presence of several phenolic and flavonoid compounds in them. Ethanolic pollen extract used by Carpes et al., (2007) in their study have shown antibacterial activity against Bacillus subtilis, Bacillus cereus Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella Spp. Studies conducted by EsinBasim et al., (2005) have shown the inhibition of growth of plant pathogenic bacteria such as Agrobaceriumtumefaciens.Pseudomonassyringaepv tomato, Xanthomonasaxonopodispvvesicatoria, Erwiniaamylovora etc. Thus the result in our study clearly reveals the antimicrobial activity of pollen extract. This is the first report on antibacterial activity of methanolic pollen extract of Cucurbitapepo against human bacterial pathogens.

References

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