Phytochemical and antibacterial characterization of five weed species presents at the province of Matanzas, Cuba

Abstract

The objective of the present work was to determine the phytochemical and antibacterial characteristics of leaf extracts of five weed species located in Coliseo, province of Matanzas, Cuba. The collected leaves were washed, dried at 45 °C, then powdered. The extractions were carried out in ethanol 90 % and water. The presence of several secondary metabolites classes was determined and it was quantified the content of total soluble carbohydrates and proteins, reducing sugar and total polyphenols. The antibacterial activity of the ethanolic extracts was determined against Gram positive and negative strains. Data were statistically analyzed by using SPSS 15.0 over Windows. Simple ANOVA and Tukey ́s Multiple Range Test were used for comparison among the media of the treatments (extracts). The phytochemical study showed terpenoids, flavonoids, saponins, steroids, tannins, coumarins and cardiac glycosides in both ethanolic and aqueous extracts of the analyzed plants. The highest content of polyphenolic compounds was observed in Bidens pilosa and Euphorbia heterophylla. The ethanolic extracts of Ageratum conyzoides, Bidens pilosa, Momordica charantia and Euphorbia heterophylla showed antibacterial activity against Staphylococcus aureus and Proteus sp. The obtained results suggest a potential use of those species for the clinical treatment of infectious diseases in humans and animals as well and they represent sources of bioactive compounds.

Keywords

• biochemistry
• plant extracts
• secondary metabolites
• proteus
• staphylococcus