Chemical characterization, antimicrobial, antioxidant, and cytotoxic potentials of Swietenia mahagoni.

Infectious diseases are the most important cause of death worldwide. Many of these diseases show great resistance to drugs and antibiotics with long-term use. Extracts of some medicinal plants have antimicrobial properties, which can treat and overcome these diseases. Meliaceae is a family of timber trees used extensively in treating many bacterial and fungal diseases, especially Swietenia mahagoni (L.) Jacq. In this study, phytochemical screening, gas chromatography/mass spectrometry (GC/MS) analysis, and antimicrobial, antioxidant, and antitumor activities of the methanolic extract of S. mahagoni (L.) leaves were performed. Phytochemical screening exhibited the presence of alkaloids, flavonoids, saponins, phenols, triterpenoids, glycosides, and tannins. GC/MS analysis exhibited 40 compounds, mainly 7-hexadecene, (Z)-, imidazole-4,5-d2, and 1-acetyl-4,4-bis[4-(3-bromopropoxy)-3,5-dimethoxyphenyl] piperidine. The antibacterial and antifungal potentials of the methanolic extract of S. mahagoni (L.) leaves was investigated using the agar well diffusion technique. Potent antibacterial activity against Staphylococcus aureus, Escherichia coli, Salmonella enterica, Enterobacter aerogenes, and Proteus vulgaris and antifungal activity against Aspergillus flavus, Aspergillus niger, and Candida albicans were found. The minimum inhibitory concentration and minimum bactericidal and fungicidal concentrations ranged from 12.5 to 25 mg/mL. Antioxidant activity was studied using the free radical scavenging assay, and the IC50 value of the leaf extract was 69.9 µg/mL. Cytotoxic activity was screened using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the IC50 value was 44.2 µg/mL. These findings suggested the importance of this plant in treating some bacterial and fungal infections and cancer.

Incorporation of Plant Extracted Hydroxyapatite and Chitosan Nanoparticles on the Surface of Orthodontic Micro-Implants: An In-Vitro Antibacterial Study.

In our study, the structural and morphological applications of hydroxyapatite and chitosan nanoparticles and coated micro-implants were assessed for their ability to combat oral pathogenic bacteria. The hydroxyapatite, as well as chitosan nanoparticles, were synthesized from the Salvadora persica plant. The crystal morphology, phase composition, particle size, and surface functional groups of the nano-samples were analyzed via classical examinations and energy dispersive X-ray analysis. The prepared nanoparticles have been examined for antibacterial activity against four common oral bacterial strains. The antimicrobial effect was also assessed by the Live/Dead BacLight technique in combination with confocal scanning laser microscopy. Titanium micro-implants were coated with regular hydroxyapatite (HAP) and chitosan nanoparticles, and the surface was characterized by scanning electron microscopy. The analysis asserted elemental composition of the prepared nanoparticles and their textural features, metal crystallization, and functional bonds. The antibacterial activity of the nanoparticles was evaluated against oral pathogenic microorganisms by the disc diffusion method, minimum bacterial concentration (MBC), and minimum inhibitory concentration (MIC). Chitosan nanoparticles showed (MICs) of 8 µg mL-1 for (Streptococcus salivarius, Streptococcus mutans and Enterococcus faecalis), and 16 µg mL-1 for Streptococcus sanguinis. HAP nanoparticles showed (MICs) of 16 µg/mL for E. faecalis, and S. sanguis, 8 µg/mL for S. salivarius and finally 4 µg/mL for S. mutans. HAP nanoparticles showed enhanced antibacterial activity and more obvious damage in the bacterial cell membrane than that of synthesized chitosan nanoparticles. The prepared nanoparticles could successfully coat titanium microplates to enhance their efficiency.

Evaluation of specific and non-specific immune response of four vaccines for caseous lymphadenitis in sheep challenged.

BACKGROUND: Caseous lymphadenitis (CLA) is a serious disease affects sheep and goat, caused by Corynebacterium pseudotuberculosis. Due to it is non-treatable disease, so the effective preventive vaccines are considered a significant way to combat the disease. All strains of C. pseudotuberculosis have several virulence factors that associated with their cell invasion, survival, and proliferation such as phospholipase D (PLD), outer lipid coat, and secreted proteases. AIM: The present study was directed to perform a comparative innate and acquired immune response assessment of different four vaccine formulas to evoke protection against induced (CLA) challenge in sheep. MATERIALS AND METHODS: Negative ELISA (free of CLA) 15 local breed male (Balady) sheep were divided into five groups, each has received a different vaccine while the control has received saline buffer. The first vaccine composed of toxoid PLD alone the second composed of toxoid PLD with bacterin (formalinkilled bacteria), the third vaccine composed of toxoid PLD plus covaccine 8, while the fourth one composed of toxoid PLD plus locally produced polyvalent clostridial vaccine. The specific immune response was evaluated through lymphocyte proliferation assay using ELISA BrdU kit, while the non-specific response was estimated by superoxide anion production and lysozyme activity assays. RESULTS: The study revealed that PLD toxoid could evoke the highest specific immune response, showing a stimulation index (9.12%). On the other hand, combined toxoid ↱PLD with bacterin followed by PLD toxoid showed a significant increase in the non-specific innate immune response. CONCLUSION: The present study indicated that the toxoid PLD alone vaccine was most efficient and provided innate and acquired immune response in animals against CLA.

Serotyping, antibiotic susceptibility, and virulence genes screening of Escherichia coli isolates obtained from diarrheic buffalo calves in Egyptian farms.

AIM: In Egypt as in many other countries, river water buffalo (Bubalus bubalis) is considered an important source of high-quality milk and meat supply. The objective of this study was to investigate serotypes, virulence genes, and antibiotic resistance determinants profiles of Escherichia coli isolated from buffalo at some places in Egypt; noticibly, this issue was not discussed in the country yet. MATERIALS AND METHODS: A number of 58 rectal samples were collected from diarrheic buffalo calves in different regions in Egypt, and bacteriological investigated for E. coli existence. The E. coli isolates were biochemically, serologicaly identified, tested for antibiotic susceptibility, and polymerase chain reaction (PCR) analyzed for the presence of antibiotic resistance determinants and virulence genes. RESULTS: Overall 14 isolates typed as E. coli (24.1%); 6 were belonged to serogroup O78 (10.3%), followed by O125 (4 isolates, 6.9%), then O158 (3 isolates, 5.2%) and one isolate O8 (1.7%), among them, there were 5 E. coli isolates showed a picture of hemolysis (35.7%). The isolates exhibited a high resistance to ß lactams over 60%, followed by sulfa (50%) and aminoglucoside (42.8%) group, in the same time the isolates were sensitive to quinolone, trimethoprim-sulfamethoxazole, tetracycline (100%), and cephalosporine groups (71.4%). A multiplex PCR was applied to the 14 E. coli isolates revealed that all were carrying at least one gene, as 10 carried blaTEM (71.4%), 8 Sul1 (57.1%), and 6 aadB (42.8%), and 9 isolates could be considered multidrug resistant (MDR) by an incidence of 64.3%. A PCR survey was stratified for the most important E. coli virulence genes, and showed the presence of Shiga toxins in 9 isolates carried either one or the two Stx genes (64.3%), 5 isolates carried hylA gene (35.7%), and eae in 2 isolates only (14.3%), all isolates carried at least one virulence gene except two (85.7%). CONCLUSION: The obtained data displayed that in Egypt, buffalo as well as other ruminants could be a potential source of MDR pathogenic E. coli variants which have a public health importance.

Catha edulis Forsk. (Khat): Evaluation of its Antidepressant-like Activity.

BACKGROUND: Catha edulis Forsk. (Khat) is traditionally used for treating various disorders. Nevertheless there are no reports of any scientific assessment of its psychopharmacological properties. OBJECTIVE: Therefore, the current study was designed to evaluate the antidepressant-like activity of Khat ethanolic extract using established animal models of depression and stress. MATERIALS AND METHODS: Ninety healthy male albino mice were used in this study. Forced swim, tail suspension and head poking tests were utilized to evaluate the antidepressant-like activity of the ethanolic extract of Khat (100, 200 and 400 mg/kg, i.p.) and escitalopram (standard drug) which were administered 30 min prior to the tests. Phytochemical analysis of the standardized extract was conducted using liquid chromatography-mass spectroscopy (LC-MS). RESULTS: A significant decrease in the head-dipping behavior was noticed after administration of 100, 200 and 400 mg/kg of Khat extract. Moreover, the extract significantly decreased the immobility time in tail suspension and forced swim tests. The presence of cathinone and cathine were detected in the extract using LC-MS. CONCLUSION: The current results suggest that the extract of Khat leaves has acute antidepressant properties and may have sedative effects. SUMMARY: Antidepressant-like activity of Khat established in vivoThe extract decreased the immobility time in tail suspension and forced swim testsLiquid chromatography-mass spectroscopy data revealed the presence of cathinone and cathine in Khat extract. Abbreviations used: LC-MS: Liquid chromatography-mass spectroscopy; NIST: National institute of standard technology; SSRI: Serotonin reuptake inhibitors; FST: Forced swim test; TST: Tail suspension test.