Broad Spectrum Antimicrobial Potential of Crassula ovata

Abstract

This study investigates the antimicrobial properties of Crassula ovata (C. ovata) against both gram-positive and gram-negative bacteria. About 1-3g samples of C. Ovata leaf samples were extracted with 95 % ethanol and the extract infused into paper discs by soaking and drying. The dried discs were screened against various strains of bacteria and the antimicrobial effects of the infused agents determined by measuring zones of inhibition due to the agents infused into the discs. By the zones of inhibition, C. ovata showed antimicrobial activity against the following gram-negative bacteria: E. coli (14 mm mean zone of clearing), P. vulgaris (13 mm mean zone of clearing), E. cloacae (16 mm mean zone of clearing), and K. pneumoniae (13 mm mean zone of clearing). C. ovata showed antimicrobial activity against the following gram-positive bacteria: S. aureus (22 mm mean zone of clearing) and S. agalactiae (8 mm mean zone of clearing). C. ovata did not show antimicrobial activity against S. pyogenes. By its antimicrobial activity against gram-positive and gram-negative bacteria, C. ovata displayed broad spectrum antimicrobial activity against E. coli, S. aureus, S. agalactiae, P. vulgaris, E. cloacae, and K. pneumoniae. C. ovata may have the potential to serve as a broad-spectrum antimicrobial in the future. Further testing should be done to investigate the toxicities and side effects of C. ovata. Further testing must also be done with C. ovata against drug-resistant strains of bacteria.

Gram-negative Antimicrobial spectrum of Ulmus pumila

“…The mixture was filtered to remove the debris. Sterile blank discs were soaked in the clear filtrate containing the active ingredient for 20 minutes as previously described [21]. The extraction solvent (95% ethanol) was also infused into a blank disc to control for vehicle effect.…”

“…The extraction solvent (95% ethanol) was also infused into a blank disc to control for vehicle effect. Glycerol stocks of bacteria were scaled as described previously [21] and agar plates were also prepared as described previously [21]. One hundred microliter suspension of the scaled bacteria was diluted with 9 ml of 1% saline solution and 100 microliters of this dilution was plated [21].…”

“…Glycerol stocks of bacteria were scaled as described previously [21] and agar plates were also prepared as described previously [21]. One hundred microliter suspension of the scaled bacteria was diluted with 9 ml of 1% saline solution and 100 microliters of this dilution was plated [21]. Discs that were infused with extracts or vehicle control (95% ethanol) were placed on bacterial plated plates.…”

“…Sample extraction, disc preparation and plating 3g of freshly harvested leaves and flower samples of Ulmus pumila were homogenized with a mortar and pestle. The homogenate was suspended in 15 ml of 95 % ethanol [21] and swirled for 15 minutes to allow time for extraction of active ingredients. The mixture was filtered to remove the debris.…”

Gram-negative antimicrobial spectrum of Ulmus pumila

“…Fresh leaves (3 grams) of Ulmus pumila were homogenized and extracted with 15 ml of 95% ethanol [26] . The filtrate from the extracted samples were impregnated into sterile blank paper disc by soaking for 20 minutes, followed by air-drying [26] .…”