The Zone of Inhibition

Ethnobotanical uses and phytochemical, biological, and toxicological profiles of Datura metel L.: A review

Datura metel L., a recognized poisonous plant in the Solanaceae family, is widely distributed in the world. Traditionally, D. metel is used in many diseases, including neurological and heart diseases; fever; catarrh; pain; diarrhea; skin diseases; chronic bronchitis; asthma; digestive disorders; and so on. It possesses many important phytochemicals that can be used to treat various types of diseases. This review aims at summarizing the traditional uses, phytochemical, biological, and toxicological profiles of D. metel based on the database reports. For this, an up-to-date (till March 20, 2023) search was made in the databases: PubMed, Google Scholar, Science Direct, Scopus, and MedLine, with relevant keywords for the published evidence. Findings suggest that the plant has many traditional uses, such as a cure for madness, epilepsy, psoriasis, heart diseases, diarrhea, mad dog bites, indigestion, etc. It possesses various important phytochemicals, including withanolides, daturaolone, datumetine, daturglycosides, ophiobolin A, baimantuoluoline A, and many others. D. metel has many important biological activities, including antioxidant, anti-inflammatory, anti-microbial, insecticidal, anti-cancer, anti-diabetic, analgesic, anti-pyretic, neurological, contraceptive, and wound healing capacity. In conclusion, the toxic plant, D. metel, can be considered a potential source of phyto-therapeutic lead compounds.

Antibacterial and bacteriostatic potential of coelomic fluid and body paste of Pheretima posthuma (Vaillant, 1868) (Clitellata, Megascolecidae) against ampicillin resistant clinical bacterial isolates

Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.

A Machine Learning Tool to Predict the Antibacterial Capacity of Nanoparticles

The emergence and rapid spread of multidrug-resistant bacteria strains are a public health concern. This emergence is caused by the overuse and misuse of antibiotics leading to the evolution of antibiotic-resistant strains. Nanoparticles (NPs) are objects with all three external dimensions in the nanoscale that varies from 1 to 100 nm. Research on NPs with enhanced antimicrobial activity as alternatives to antibiotics has grown due to the increased incidence of nosocomial and community acquired infections caused by pathogens. Machine learning (ML) tools have been used in the field of nanoinformatics with promising results. As a consequence of evident achievements on a wide range of predictive tasks, ML techniques are attracting significant interest across a variety of stakeholders. In this article, we present an ML tool that successfully predicts the antibacterial capacity of NPs while the model's validation demonstrates encouraging results (R2 = 0.78). The data were compiled after a literature review of 60 articles and consist of key physico-chemical (p-chem) properties and experimental conditions (exposure variables and bacterial clustering) from in vitro studies. Following data homogenization and pre-processing, we trained various regression algorithms and we validated them using diverse performance metrics. Finally, an important attribute evaluation, which ranks the attributes that are most important in predicting the outcome, was performed. The attribute importance revealed that NP core size, the exposure dose, and the species of bacterium are key variables in predicting the antibacterial effect of NPs. This tool assists various stakeholders and scientists in predicting the antibacterial effects of NPs based on their p-chem properties and diverse exposure settings. This concept also aids the safe-by-design paradigm by incorporating functionality tools.

Antimicrobial Activity of Some Sudanese Medicinal Plants Against its Pollutant Isolated Bacteria

<b>Background and Objective:</b> Medicinal plants have been known to cure many diseases due to the presence of active bio constituents, the goal of this study to detect and evaluate the effectiveness of antimicrobial activity of some Sudanese medicinal plants. <b>Materials and Methods:</b> Methanolic extracts of the following types of local medicinal plants <i>Artemisia herba-alba</i>,<i> Cyperus rotundus</i>,<i> Cymbopogon schoenanthus </i>sb<i> </i>sp.<i> Proximus</i>,<i> Trigonella foenum-graecum</i>,<i> Nigella sativa</i>,<i> Hyphaene thebaica</i>,<i> Nauclea latifolia</i> and <i>Ziziphus spina-christi</i> were tested against eight types of bacteria that were isolated from the same plants as their pollutants. Cup-plate method was used and then the inhibition zone of each plant was measured and compared with the inhibitory zone of some antibiotics used for the same isolates. <b>Results:</b> Methanol extracts of some plant species showed antibacterial activity against most of the studied bacterial species. <i>Cymbopogon schoenanthus </i>ssp.<i> Proximus </i>showed antibacterial activity against most isolated bacterial species in comparison with commercial antibiotics used. <b>Conclusion:</b> According to the findings of this research, severalmedicinal plants have efficacy and effect on certain types of bacteria and are superior or comparable to certain types of antibiotics. When compared to the other medicinal plants used in this study<i>, Cymbopogon schoenanthus </i>sbsp. <i>proximus </i>has the highest activity on most types of Gram-positive and Gram-negative bacteria, as well as the superiority of some antibiotics.

Antibacterial Activities of Calpurnia aurea against Selected Animal Pathogenic Bacterial Strains

The study aimed to determine the phytochemicals and to assess the antibacterial activities of crude extracts of different parts of Calpurnia aurea against Staphylococcus aureus, Streptococcus pyogenes, Listeria monocytogenes, Escherichia coli O157 H:7, Salmonella typhi, and Campylobacter jejuni. The fresh and healthy leaves, barks, stems, and roots of the plant parts were collected, herbarium, dried, and grounded, and bioactive compounds were extracted by ethanol (99%) and water. Mass of crude extracts was determined by using the Whatman No. 1 filter paper and rotary evaporator. Major secondary metabolites were also screened using phytochemical screening tests. Antibacterial activities (inhibition zones, mm) and minimum inhibition concentrations (MIC) were evaluated using agar-well diffused methods and agar dilution methods, respectively. The antibiotics ciprofloxacin, amoxicillin, penicillin, and tetracycline were used as positive controls at concentrations of 0.1 mg/ml and 0.2 mg/ml, while distilled water was used as the negative control. All the crude extracts were tested triplet (3x) for antibacterial activities against selected bacterial strains with two different concentrations 25 and 50 mg/ml and analyzed to compare the mean ± standard deviation between triplets. The results revealed that ethanol extracts showed high crude mass extracts, antibacterial activities, and major secondary metabolites such as alkaloids, tennis, flavonoids, saponins, steroids, and phlobatannins compared with aqueous extracts. Among antibiotics used, penicillin showed resistance to S. aureus and E. coli O157 H:7. C. jejuni was found to be the most susceptible bacterium to ethanol extracts' leaves, barks, and stems with MIC 3.125 mg/ml, whereas S. aureus was the least susceptible to all crude extracts. The study provided the traditional and scientific basis of Calpurnia aurea used against some bacterial diseases.