Antimicrobial activity of natural products from the flora of Northern Ontario, Canada
Bibliographic record
Abstract
CONTEXT: The number of multidrug resistant (MDR) microorganisms is increasing and the antimicrobial resistance expressed by these pathogens is generating a rising global health crisis. In fact, there are only a few antimicrobial agents left that can be used against MDR bacteria and fungi. OBJECTIVE: In this study, the antimicrobial activities of selected natural products from the flora of Northern Ontario against selected microorganisms are reported. MATERIALS AND METHODS: Plants were collected from Sault Ste. Marie, Ontario, Canada, and ethanol extracts were prepared using EtOH:H2O (1:1, v/v). Fungal cultures used in this study were Candida albicans ATCC 10231 and Schizosaccharomyces octosporus. Bacterial cultures employed included Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Mycobacterium phlei ATCC 11758, and Streptococcus lactis ATCC 19435. The microplate resazurin assay was used to screen for antimicrobial activity. RESULTS: Extracts of four plant species Chimaphila umbellata L. (Pyrolaceae), Betula papyrifera Marshall (Betulaceae), Rhus typhina L. (Anacardiaceae), and Fraxinus pennsylvanica Marshall (Oleaceae), and six compounds (gallic acid, ethyl gallate, caffeic acid, sinapic acid, gentisic acid, and chlorogenic acid) demonstrated antibacterial or antifungal activities with MICs ranging from 62.5 to 1000 µg/mL, respectively, for a chemical fraction of an extract from Betula papyrifera against the bacterium S. aureus. DISCUSSION AND CONCLUSION: The present study has shown that certain plant extracts and select fractions and standard chemical compounds exhibit antimicrobial effects. Prince's Pine, Chimaphila umbellate, White Birch, Betula papyrifera, Staghorn Sumac, Rhus typhina, and Green Ash, Fraxinus pennsylvanica were the principal extracts exhibiting notable antibacterial and/or antifungal activities; while gallic acid, ethyl gallate, and caffeic acid demonstrated antibacterial activities and sinapic acid, gentisic acid, and chlorogenic acid demonstrated antifungal activities.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".