Biology subjects

Schafer, J.

Publications and source records attributed to Schafer, J..

4 recordsLinked to original sources

bioRxiv2022

Gram-negative Antimicrobial spectrum of Ulmus pumila

PurposeThis study explores the antimicrobial spectrum of Ulmus pumila by screening commonly infectious gram-negative bacteria for susceptibility. Currently, many gram-negative bacteria are developing resistance to recommended antibiotic therapies used in clinical practice. It is imperative that we continue to explore new antimicrobial compounds in order to help combat the global health issue of antibiotic resistance. Method3g of freshly harvested leaves and flower samples of Ulmus pumila were extracted in 15 ml of 95% ethanol. The mixture was filtered to remove the debris and sterile blank discs were soaked in the clear filtrate (samples) or the extraction solvent (as background controls) for 20 minutes. Glycerol stocks of bacteria were scaled in LB broth and Muller Hinton agar was prepared with 38g of agar in a liter of water. A 100-microliter suspension of the scaled bacteria was diluted with 9 ml of 1% saline solution and 100 microliters of this saline dilution was plated. Sterile paper discs that were infused with extracts (samples) or vehicle control (95% ethanol) were placed on the freshly plated bacterial plates and incubated at 37 degree Celsius overnight. Zones of inhibition were recorded as a measure of antibacterial activity. ResultUlmus pumila demonstrated antimicrobial activity against the following gram-negative bacteria: E. coli (16 mm mean zone of clearing), P. vulgaris (15 mm mean zone of clearing), E. cloacae (20.5 mm mean zone of clearing), and K. pneumoniae (16 mm mean zone of clearing). ConclusionUlmus pumila displayed antimicrobial activity against various species of gram-negative bacteria including E. coli, P. vulgaris, K. pneumonaie, and E. cloacae. Ulmus pumila has also previously demonstrated activity against some species of gram-positive bacteria. By this discovery, Ulmus pumila has the potential to serve as a broad-spectrum antimicrobial agent with activity against both gram-positive and gram-negative bacteria.

microbiology↗

bioRxiv2022

Broad-Spectrum Antimicrobial Potential of Crassula ovata

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.

microbiology↗

bioRxiv2021

Investigating Increased CO2 concentration on the pH of various plant species

The concept of bioremediation is quickly becoming the norm in the resolution of environmental issues. The steady increase in carbon dioxide (CO2) levels, as documented by NASA, inspired scientists to engineer plants to absorb excess CO2 from the atmosphere. Here, we have explored the consequences of the uptake of excess CO2 by select plants. Carbon dioxide dissolves in H2O to produce H2CO3, which dissociates to yield H+ ions. We hypothesized that increased CO2 absorption results in decrease in pH of plant sap. Three plants (Byophyllum pinnatum, Romaine Lettuce and Nevada Lettuce), exposed to increased CO2 concentrations (15%), demonstrated a consistent increase in pH towards alkalinity compared to control plants. Based on the outcome being opposite of what we have hypothesized, our results suggest Byophyllum pinnatum, Romaine lettuce and Nevada lettuce, all have a unique homeostatic system to prevent over-absorption of CO2 in a CO2-rich environment.

ecology↗

bioRxiv2021

Early Disruption of Photoreceptor Cell Architecture and Loss of Vision in a Humanized Pig Model of Usher Syndrome

Usher syndrome (USH) is the most common form of monogenic deaf-blindness. Loss of vision is untreatable and, so far, there are no suitable animal models for testing therapeutic strategies. By introducing a human mutation into the harmonin-encoding USH1C gene in pigs, we generated the first translational animal model for USH type 1 with characteristic hearing defect, vestibular dysfunction and visual impairment. Changes in photoreceptor architecture, quantitative motion analysis and electroretinography were characteristics of the reduced retinal virtue in USH1C pigs. Primary cells from those animals and USH1C patients showed significantly elongated primary cilia, compared to wild-type, confirming the nature of USH as a true and general ciliopathy and proving the therapeutic capacity of gene supplementation and gene repair approaches.

genetics↗