Anti-bacterial activity of Ricinus communis L. against bacterial pathogens Escherichia coli and Klebsiella oxytoca as evaluated by Transmission electron microscopy

Abstract

The emergence of multidrug-resistant (MDR) microbes has become one of the major threat globally. Infectious diseases are the second leading cause of death, two-third of which are caused by Gram-negative bacteria. The increasing number of multidrug resistant (MDR) microbes is quite alarming and has raised the necessity of development of new antibacterial drugs. Escherichia coli and Klebsiella have been reported among the top most resistance-developing pathogens. Ricinus communis is an important medicinal plant reported to possess antimicrobial phytochemicals such as a-pinene. The hexane treated crude ethanolic extract of R. communis was evaluated against Gram-negative bacteria E. coli and Klebsiella oxytoca. The agar well diffusion assay was used to determine the antibacterial activity. In the present study, we have shown experimentally that leaf extract of R. communis can induce the deterioration of the inner and outer cell membranes of E. coli and K. oxytoca and decrease their viability at a concentration of 50 mg/ml. Transmission electron microscopic results revealed cell membrane damage, cellular disintegration and release of cytoplasmic content, leading to cell death. To our knowledge, this is the first study of the antibacterial activity of R. communis against E. coli and K. oxytoca by Transmission electron microscopy. The ultramicroscopic observations showed that the phytochemical present in the leaf extract of R. communis could penetrate the bacterial cell, causing rupture of cell membranes and hence confirm the cytotoxic and antimicrobial property of R. communis.

The polyphenol/saponin-rich Rhus tripartita extract has an apoptotic effect on THP-1 cells through the PI3K/AKT/mTOR signaling pathway

“…Except for saponins and kaempferol at the highest concentration, all the treatments strongly decrease the expression level of AKT1, especially the total plant extract (RTE) and the highest concentrations of rutin and catechins mix. This agrees with other studies showing downregulation of PI3K/AKT/mTOR in response to treatments with plant phytochemicals extracted from Ricinus communis [61], Alpinia nantoensis [62], Taraxacum o cinale [63]. Moreover, the eIF4E and TSC1 genes, acting as negative regulators of mTOR [64], were upregulated in our study, thus strengthening once more the inhibitory effect that Rhus tripartita extracts have on THP-1 cell proliferation.…”

Bactericidal Potentiality of Purified Terpenoid Extracts from the Selected Sea Weeds and its Mode of Action

“…Similar changes in the bacterial cells treated with oregano and thyme essential oils and there by confirmed their antimicrobial power against E. coli O157:H7 [19]. Burt [18] [22,23,24,25,26,27].…”

Gene expression profiling to elucidate the pharmacological and toxicological effects of Ricinus communis L. leaf extract in mammalian cells

“…Besides, the above-mentioned potential therapeutic applications, Ricinus plant extracts have also been shown to possess potent anti-bacterial activity [41]. In addition to its application in medicine, R. communis is applied in cosmetics, animal feed and in the manufacturing of biodiesel, plastics and lubricants [42].…”