Bioactivity and Chemical Characterization of Sudanese Bee Honey: Crude Acacia and Its Organic Extracts.

Honey has recently been rediscovered as an antibacterial and wound-healing natural product. The medicinal properties of honey originate from the floral source used by bees. The objective of the current study was to evaluate the antimicrobial activity of Sudanese crude acacia bee honey and its solvent extracts regarding its biological activity and chemical characterization. To verify the nature of the antibacterial agent(s) of honey, sample (A) Sudanese crude unprocessed acacia bee honey obtained from west of Sudan (Nyala) during October 2019 was tested in vitro for antibacterial activity against 10 standard microorganisms Enterobacter aerogenes: ATCC: 13048, Enterococcus faecalis: ATCC: 29212, Escherichia coli: ATCC: 25922, Klebsiella pneumoniae: ATCC: 700603, Pseudomonas aeruginosa: ATCC: 27853, Serratia marcescens: ATCC: 8100, Staphylococcus aureus: ATCC: 29213, Staphylococcus epidermidis: ATCC: 12228, Staphylococcus Methicillin Sensitive MSSA: ATCC: 29213, and Staphylococcus Methicillin-Resistant MRSA: ATCC: 23591. Extraction of honey sample was carried out by petroleum ether followed by ethyl acetate using liquid/liquid extraction technique, using separating funnels. All organic extracts in addition to their aqueous residue were tested in vitro for antibacterial activity against the10 standard microorganisms. Ethyl acetate extract was subjected to gas chromatography-mass spectrometer (GC-MS) for chemical characterization. Sudanese crude unprocessed acacia honey showed inhibitory effects against the 10 standard microorganisms. Petroleum ether extract showed no antibacterial activity against the tested organisms, while its water residue exhibited remarkable activity. The ethyl acetate extract exhibited strong antibacterial activity against the tested organisms, while its aqueous residue showed no activity. Ethyl acetate extract subjected to gas chromatography-mass spectrometer (GC-MS) showed twenty-one chemical constituents. The GC-MS showed twenty-one chemical compounds, and phenolic compound was the highest concentration. Ethyl acetate extract exhibited strong antibacterial activity which can be formulated as topical dressing for wounds and burns. The usage of honey in a professional context should be taken into consideration while treating burns and wounds.

In Vitro Antibacterial Activity of Different Honey Samples against Clinical Isolates.

BACKGROUND: The emergence of multi-drug-resistant organisms has created a lot of clinical problems. Hence, there is a need to find natural alternative treatment to counter the multi-drug-resistant organisms. Honey has a well-established usage as wound dressing in ancient and traditional medicine. OBJECTIVE: The objective of this study is to establish a baseline for the antibacterial activity of 32 global raw natural and commercial various honey samples against 8 clinical isolates. METHODS: Thirty-two honey samples (raw and commercial honey) collected from different global countries with different floral origins were tested in vitro for antibacterial activity against 8 clinical isolates collected from patients, at private hospital from Sudan, using disk diffusion technique. The following 6 epsilometer tests (Etest), amoxicillin, ciprofloxacin, cefotaxime, chloramphenicol, gentamicin, and tetracycline, were used against 8 clinical isolates for Minimum Inhibitory Concentration (MIC). RESULTS: The following 8 clinical isolates were identified by conventional bacteriological methods: Staphylococcus aureus, (S. aureus) Escherichia coli (E. coli), Klebsiella pneumoniae (K. pneumoniae), Pseudomonas aeruginosa (P. aeruginosa), Proteus vulgaris (P. vulgaris), Salmonella Typhi (S. Typhi), Shigella sonnei (S. sonnei), and methicillin-resistant Staphylococcus aureus (MRSA). Both raw natural and commercial honey exhibited antibacterial properties against tested Gram-positive and Gram-negative bacteria. The tested organisms showed low sensitivity to antibiotic Etest. CONCLUSION: All of the bacterial species studied were uniformly receptive to all raw and commercial tested honey samples; in contrast, the tested organisms showed low sensitivity to antibiotics. Commercial honey has the same antibacterial activity as the raw natural unprocessed honey against tested clinical isolates. Thus, honey is a successful alternative to conventional antibiotics as has been proved against clinical isolates.

Antimicrobial Activity of Synthesized 2-Methylthiobenzo[g][1,2,4]- triazolo[1,5-a]quinazoline Derivatives.

BACKGROUND: The present study was carried out to evaluate the antimicrobial activity of a synthesized 2-methylthio-benzo[g][1,2,4]triazolo[1,5- a]quinazoline series. The compounds (1-21) were tested against a variety of Gram-positive bacterial species including Bacillus subtilis (RCMB 01001 69-3), Enterococcus faecalis (RCMB 0100154-2), Staphylococcus aureus (RCMB 0100183-9), Staphylococcus epidermidis (RCMB 0100183-9) and Streptococcus pyogenes (RCMB 0100172-5). In addition, Gram-negative bacteria were also tested including Pseudomonas aeruginosa (RCMB 0100243-5), Escherichia coli (RCMB 010052-6), Proteus mirabilis (RCMB 01002 54-2), Klebsiella oxytoca (RCMB 01002 83-4) and Enterobacter cloacae (RCMB 01002 64-5). Furthermore, their activities were screened against ten types of fungi i.e. Aspergillus fumigatus (RCMB 02568), Syncephalastrum racemosum (RCMB 05922), Geotricum candidum (RCMB 05097), Candida albicans (RCMB 05036), Aspergillus niger (RCMB 02724), Cryptococcus neoformans (RCMB 05642), Candida tropicalis (RCMBA 05239), Penicillium expansum (RCMB 01924), Microsporum canis (RCMB 0834) and Trichophyton mentagrophytes (RCMB 0925). METHODS: Evaluation of antimicrobial activity was performed using agar well diffusion method in comparison with ampicillin and gentamycin as antibacterial reference drugs, and amphotericin B as antifungal reference drug. The minimum inhibitory concentration (MIC) was determined using the broth double dilution technique. RESULTS: The MIC values of the tested compounds were reported in .g/mL in which ampicillin, gentamicin and amphotericin B were used as standard reference drugs. The obtained results revealed that compounds 3, 4, 7, 8, 9, 10, 11, 14, 17, 18, 19, 20 and 21 showed significant antimicrobial activity against six bacterial and six fungal strains. CONCLUSION: The promising compounds could be employed as useful scaffolds for building of new derivatives with more potent antimicrobial effects.