Antibacterial potential of extracts of various parts of &lt;i&gt;Catunaregam tomentosa&lt;/i&gt; (Blume ex DC) Tirveng and their effects on bacterial granularity and membrane integrity

Darika Kongrit,Karnsiree Thimabut,Patima Permpoonpattana,Amornrat Keawkumpai,Theera Srisawat,Parinuch Chumkaew,Saranyoo Klaiklay,Jaraslak Pechwang

doi:10.4314/tjpr.v17i5.18

Abstract

Purpose : To investigate the antibacterial activity of extracts from C atunaregam tomentosa on Bacillus subtilis and Staphylococcus aureus , and the bacterial responses to the extracts. Methods: The antibacterial activity of fruit, leaf and stem bark extracts were evaluated against B. subtilis (ATCC6633) and S. aureus (ATCC25923). Using a disc diffusion method, extracts at concentrations ranging from 50 – 1,000 μg/disc were tested. The minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) of the extracts against the test bacteria were determined. Fluorescent activated cell sorting (FACS) was used to assess the responses of both types of bacteria to the extracts. Results : The fruit and leaf extracts at 1,000 μg/disc showed optimum efficacy against B. subtilis and S. aureus with MIC of 1,000 μg/mL against both B. subtilis and S. aureus, for the fruit and the leaf extracts. With increasing doses of fruit and leaf extracts at 6 h of incubation, FACS profiles revealed that cell death for B. subtilis increased. The fruit and leaf extracts of C. tomentosa also exhibited antibacterial activity against S. aureus in a dose- and time-dependent manner. The bacteria initially lost their granularity, then lost membrane integrity, and consequently died. Conclusion : The fruit and leaf extracts of C. tomentosa exhibit significant antibacterial potential against Gram-positive bacteria by damaging bacterial granularity and membrane integrity. Keywords : Catunaregam tomentosa, Flow cytometry, Programmed cell death, Response pattern, Bacterial granularity, Membrane integrity

Highlights

In recent years multidrug-resistant (MDR) pathogenic bacteria have been increasingly reported, largely due to a history of indiscriminate use of various antibiotics
Traditional medicine tends to rely on medicinal herbal plants, and such medicinal plants may provide novel phytochemicals to use as bactericides [3]
The antimicrobial activities of C. tomentosa fruit, leaf, and stem bark extracts were studied with two types of Gram positive bacteria

Summary

INTRODUCTION

In recent years multidrug-resistant (MDR) pathogenic bacteria have been increasingly reported, largely due to a history of indiscriminate use of various antibiotics This process selects for the resistant strains, killing off the competing non-resistant bacterial population. The sticky mass was weighed and stored at 4 oC until further use These constituted the three concentrated extracts, representing fruit, leaf, and stem bark. The bacterial strains were cultured on nutrient agar (NA) plates and incubated for 18 to 24 h at 37 oC. One mL of extract solution was added to the first tube containing 1 mL of sterile trypticase soy broth with 1 × 107 CFU/mL bacteria, resulting in a final concentration of extract of 1,000 μg/mL. The data obtained from antibacterial studies were analyzed using SPSS statistical software, version 11.0 (SPSS Inc., Chicago, IL, USA)

RESULTS

DISCUSSION

CONCLUSION