Study on Antibacterial Activity of 2-Methyl-3-(methylthio)Pyrazine Against Three Strains of Spoilage Bacteria

Previous studies have shown that glycine and proline are pharmacophores that display antibacterial activity.In the present study,glycine and proline were derivated to diketopiperazine compounds by chemical synthesis method,and their antibacterial activities were evaluated by three strains of spoilage bacteria,Escherichia coli,Pseudomonas aeruginosa and Shewanella putrefaciens,and the relationship of their antibacterial activities and structures was also investigated.Uv-vis spectrophotometry was used to determine the growth curves of three kinds of active indicator bacteria.Minimum inhibitory concentration(MIC)was determined by micro broth dilution method.The results showed that 2-methyl-3-(methylthio)pyrazine had significant antibacterial activity against three strains of the bacteria,and its MIC was 1.25%.It indicates 2-methyl-3-(methylthio)pyrazine has the potential to be developed as a kind of preservative in future.

Aspirin increases susceptibility of Helicobacter pylori to metronidazole by augmenting endocellular concentrations of antimicrobials

AIM： To investigate the increasing the susceptibility pylon） to metronidazole. mechanisms of aspirin of Helicobacter pylori （H METHODS： Hpylori reference strain 26695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin （1 mmol/L）. The rdxA gene of Hpylori was amplified by PCR and sequenced. The permeability of Hpylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-^3H]-tetracycline. The outer membrane proteins （OMPs） of Hpylori 26695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins （hopA, hopB, hopC, hopD and hopE） and the putative RND efflux system （hefABC） of H pylori were analyzed using real-time quantitative PCR. RESULTS： The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of aspirin.The expression of the mRNA of hopA, hopB, hopC, hopD, hopE and herA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION： Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of Hpylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.

Study of the Effectiveness of Papaver Sp. Alkaloids as Future Therapeutic Alternatives against Enterococcus Sp. Causing Hospital-Acquired Septicemic Infections

Background and Objective: In recent years, control of Enterococcus sp. It has been proven in the local medical environment to be a cause of acquired septicemia in various age groups, and medical instruments are considered an effective means of transmitting enterococcal septicemia, and catheters are at the forefront in terms of danger. Based on this risk, this study aimed to monitor the spread of Enterococcus sp., which causes blood poisoning acquired from catheters, and to compare its response to antibiotics with that of those isolated from clinical samples in children, as a first study locally. The effectiveness of alkaloids of different types of Papaver sp. In Syrian plants, they were tested against infection with this bacteria. Materials and Methods: The study dealt with two parts: The first part included collecting clinical samples from the University Children’s Hospital in Damascus/bacterial diagnostic laboratories/then isolating and diagnosing the bacteria by following a set of tests to identify the most prevalent genera and species and comparing their prevalence rate with Enterococcus. The second part;It included collecting plant samples, confirming the species taxonomically, then extracting alkaloids from plant parts (fruit, stem, Flowers), then comparing the extent of resistance of bacterial strains to antibiotics compared to the Enterococcus sp., and then confirming the antibacterial activity of the Papaver sp. alkaloids against Enterococcus sp. Result:In its first part, the study confirmed the significant contribution of the Enterococcus sp. to infections acquired from various sources, largely in catheter tip infections (9.09%) and to a lesser extent in other sources (3.7%), The second part was to confirm the effective-ness of the alkaloid extract of the Papaver sp., especially the two species Papaver syriacum, and Papaver dubium, against Enterococcus sp. with areole diameters that ranged between (15 - 26 mm) for the fruit extract and at a minimum inhibitory concentration (3.12 - 6.25 mml) and then the stem (5 - 20 mm). And the effectiveness of the Flowers extract is very weak to almost non-existent. Conclusions: The catheter and medical sources surrounding the patient constitute a dangerous source of multi-resistant Enterococcus sp., which poses a real threat to the lives of children, with new mechanisms represented by colonization of the skin and the ability to form biofilms Surfaces of medical instruments, with are resistant to a wide range of antibiotics. As an alternative and effective modern source to limit its spread in the future, the alkaloid extract of the fruits and stems of the wild Papaver sp. has proven a strong antibiotic effect, especially the two types: Papaver syriacum and Papaver dubium.

In Vitro Anti-Bacterial and Anti-Fungal Activities of Extracts from Different Parts of 7 Zingiberaceae Plants

This study aimed to explore the anti-bacterial and anti-fungal activities of extracts from different parts of plants in the Zingiberaceae family.The inhibitory rate,minimum inhibitory concentration(MIC),and minimum bactericidal concentration(MBC)of leaf and stem,and root and rhizome extracts from Alpinia katsumadai Hayata,Alpinia oxyphylla Miq×Alpinia henryi K.Schumann,Alpinia oblongifolia Hayata,Alpinia nigra(Gaertn.)Burtt,Amomum villosum Lour,Alpinia zerumbet(Pers.)Burtt.et Smith and Alpinia oxyphylla Miq were determined using the fungus cake method and double dilution method.The seven Zingiberaceae plants exhibited characteristic antibacterial activities against pathogenic bacteria and fungi.At a 1.5 mg mL^(−1),A.zerumbet root and rhizome extracts exhibited strong inhibitory activity against S.aureus and E.coli,with 83.23%and 79.62%,respectively.In addition,A.zerumbet leaf and stem extracts had an inhibitory rate of 90.85%against P.aeruginosa.At the same concentration,the leaf and stem,root and rhizome extracts of A.katsumadai had the best anti-bacterial effect against F.oxysporum,with inhibition rates of 84.46%and 84.73%,respectively.Moreover,A.katsumadai and A.zerumbet leaf and stem extracts had the most significant antibacterial effect against S.aureus,with a MIC of 0.063 mg mL^(−1).Thus,both A.katsumadai and A.zerumbet extracts had significant antibacterial activity.In addition,by comparing the inhibitory effect of extracts from different parts,it was found that the inhibitory rate and average inhibitory rate of extracts from leaf and stem were higher than those from root and rhizome.The chemical constituents of A.katsumadai and A.zerumbet,determined by the high-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS),revealed that citric acid(CA),alpinetin,and pinocembrin(PNCB)were the functional constituents yielding the antibacterial activity.Overall,A.katsumadai and A.zerumbet have the potential to be developed as new plant fungicides and bactericides.

Identification and antibiotic susceptibility evaluation of Mycoplasma synoviae isolated from chickens in central China

Mycoplasma synoviae(M.synoviae)infections have become an increasingly serious concern in China because they cause huge economic losses to the poultry industry.Antibiotic treatment is one of control strategies that can be used to contain clinical outbreaks in M.synoviae-free flocks,especially because the bacteria can be transmitted through eggs.To understand M.synoviae infection status in farms of central China and the antibiotic susceptibility of the circulating strains in vivo and in vitro,485 samples were collected from five provinces from 2019 to 2021.Fifty-two strains were isolated and identified.Determination of the minimum inhibitory concentration(MIC)of eight antibiotics(tylvalosin,tiamulin,tilmicosin,lincomycin,enrofloxacin,chlortetracycline,doxycycline and tylosin)for isolates showed that tylvalosin,doxycycline and tiamulin were effective against 52 clinical isolates(MIC values≤0.0625-0.25μg/mL,≤0.0625-1μg/mL,and 0.25-2μg/mL,respectively).Tilmicosin,enrofloxacin and lincomycin had high MICo values(>32μg/mL).An artificial M.synoviae infection model was established in chickens for evaluation of the short-term therapeutic effect of these antibiotics.After 5 days of medication,doxycycline(200 mg/L)showed a superior ability to inhibit M.synoviae compared with other groups,as did tylvalosin(200 mg/L).Furthermore,the therapeutic efficacy of tylvalosin(0.4μg/mL)on intra-embryo-injected M.synoviae was higher than that of tiamulin at the same dose.A combination of MiC values determined in vitro and therapeutic effects observed in vivo revealed that tylvalosin and doxycycline had the best therapeutic effects.Tylvalosin also showed better inhibitory effects on the vertical transmis-sion of M.synoviae than tiamulin.

Enhancing Accumulation and Penetration Efficiency of Next-Generation Antibiotics to Mitigate Antibiotic Resistance in Pseudomonas aeruginosa PAO1

This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and introduced a novel adjuvant, Influximax, which augmented its antibacterial activity. Results showed a diminished potential for resistance emergence with Antibiotic B, particularly when used in combination with Influximax. The study suggests that optimizing antibiotic delivery into bacterial cells and leveraging syner-gistic adjuvant combinations can enhance drug resistance combat. .

Screening test for anti-Helicobacter pylori activity of traditional Chinese herbal medicines

AIM:To evaluate the anti-Helicobacter pylori (H.pylori) activity of 50 traditional Chinese herbal medicines in order to provide the primary evidence for their use in clinical practice.METHODS:A susceptibility test of water extract from 50 selected traditional Chinese herbal medicines for in vitro H.pylori Sydney strain 1 was performed with broth dilution method.Anti-H.pylori activity of the selected Chinese herbal medicines was evaluated according to their minimum inhibitory concentration (MIC).RESULTS:The water extract from Rhizoma Coptidis,Radix Scutellariae and Radix isatidis could significantly inhibit the H.pylori activity with their MIC less than 7.8 mg/mL,suggesting that traditional Chinese herbal medicines have anti-inflammatory and antibacterial effects and can thus be used in treatment of H.pylori infection.CONCLUSION:Rhizoma Coptidis,Radix Scutellariae and Radix isatidis are the potential sources for the synthesis of new drugs against H.pylori.

Characterization of bla_(CTX-M) Gene in One Klebsiella pneumoniae Isolate from Sick Chickens in China

Two Klebsiella pneumoniae isolates （Kpcl and Kpc2） were obtained from liver samples of seven dead chickens and identified with Vitek-32 automated identification system. Antimicrobial susceptibilities were determined by the microdilution broth method. Detection of genes encoding class A β-lactamases was performed by PCR amplification, and cloning of the ESBL gene was by plasmid restriction and fragments ligation. Conjugation assay, transformation experiments and plasmid profile analysis were performed. The incompatibility group of ESBL-carrying plasmid was determined by the PCR-based replicon typing method. Lastly, the genetic environment was analysed by direct sequencing of the DNA surrounding the ESBL gene. The genes associated with tetracycline and gentamicin resistance were also sought by PCR. The results revealed that the ESBL phenotype-negative strain Kpc2 only showed resistance to ampicillin, amoxicillin, tetracycline, and doxycycline and carried bla TEM-1 and tet（A） genes. The ESBL-producing strain Kpcl exhibited multidrug resistant phenotype and harbored bla TEM-1 , bla CTX-M-14, tet（A）, tet（B）, and rmtB genes. K. pneumoniae Kpcl contained four plasmids with molecular sizes of approximately 59, 6.9, 2.8, and 1.6 kb, but only a 59-kb plasmid, carried bla TEM-1 and blac CTM-14 genes, was observed in its transconjugant. The incompatibility group of plasmid carrying blaCTX-M-14 gene could not be determined. The bla CTX-M-14 gene was flanked upstream by an ISEcpl insertion sequence and downstream by an IS903 element. This work shows that CTX-M-14 is present in K. pneumoniae isolates from chickens in China. The bla CTX -M-4 gene was associated with an upstream ISEcpl insertion sequence. Our results underline the need for continuous surveillance of the prevalence and evolution of this CTX-M-type β-lactamase in China.

Aqueous and organic extracts of Trigonella foenum-graecum L.inhibit the mycelia growth of fungi

Aqueous extracts from various plant parts of fenugreek(3%)(aerial parts:leaves and stems(LS),roots(R),ground seeds(GS)and not ground seeds(NGS))and petroleum ether,ethyl acetate and methanolic fractions of the aerial parts were assayed to determine their antifungal potential against Botrytis cinerea,Fusarium graminearum,Alternaria sp.,Pythium aphanidermatum,and Rhizoctinia solani.All fenugreek plant parts showed antifungal potential and the magnitude of their inhibitory effects was species and plant parts d...

Antimicrobial potential of Terminalia chebula Retz. fruit extracts against ear pathogens

AIM： To evaluate the antimicrobial potential of Terminalia chebula （ T. chebula） extracts against pathogens causing otitis externa and compare it with ear drops.METHODS： Four different extracts, methanol, ethanol, acetone and aqueous （hot and cold） extracts, from the T. chebula were tested for their antimicrobial activity through the agar well diffusion method and minimum inhibitory concentration （MIC）/minimum bactericidal concentration （MBC） values were determined through the macrodilution broth method against six different microorganism, five bacterial （one gram positive and four gram negative） and one yeast.RESULTS： Organic and aqueous fruit extracts displayed activity against all fve tested bacterial ear pathogens with a maximum zone of inhibition of 31.6 mm against Staphylococcus aureus , followed by Acinetobacter sp. （24.6 mm）, Pseudomonas aeruginosa （23.6 mm）, Proteus mirabilis （21 mm） and Escherichia coli （19.3mm）. Of the four solvents evaluated, acetonic fruit extract of T. chebula was found to be best. The MIC values ranged between 0.78 mg/mL and 50 mg/mL for the different bacterial ear pathogens and MBC values ranged between 1.56 mg/mL and 50 mg/mL. The acetonic fruit extract showed larger inhibition zones compared to the herbal ear drops, Kan pip with lowest MIC of 0.78 mg/mL and MBC of 1.56 mg/mL.CONCLUSION： Acetonic extract of T. chebula fruit may be used to treat otitis externa. However, more detailed studies, such as in vivo testing and pharmacokinetics properties, are needed to determine its therapeutic potential.

Studies on Antibacterial Effect of Berberis julianae Schneid and Cinnamomum camphora( L.) Presl. to Avian Escherichia coli and Salmonella

[Objective]This study aimed to observe the antibacterial activity of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. aqueous extracts and their antibiotical effect when being used with commonly used antibiotics in- vitro. [Method] Broth microdilution method and checkerboard dilution method were used and the reference strain E. coli ATCC25922 and clinical sample separation strains of E. coli and Salmonella were selected to determine the minimum inhibitory concentration（ MIC） and fractional inhibitory concentration（ FIC）. [Result] The MICs of Berberis julianae Schneid and Cinnamomum camphora（ L.） Presl. for E. coli and Salmonella were both 1 mg /mL,and that of other antibiotics for the two strains were in the quality control range provided by NCCLS. [Conclusion] The synergistic effect or additive effect were observed when they were applied with the commonly used antibiotics.

Synthesis, Antibacterial Activities and Theoretical Studies of Benzopyranocoumarin Derivatives

Three benzopyranocoumarins（OBH, OMH and ODH） were synthesized and characterized via IR, ^1H NMR and HRMS. The HB energy in OBH, OMH and ODH was performed with the density functional theory（DFT） [B3LYP/6-31G＊] method. The in vitro antibacterial activity of OBH, OMH and ODH against drug-sensitive S. aureus（S. aureus ATCC 29213） strain, MRSA strain（MRSA XJ 75302）, drug-sensitive S. epidermidis strain（S. epidermidis ATCC 14990） and methicillin-resistant S. epidermidis strain（MRSE XJ 75284） was evaluated by observing the minimum inhibitory concentration. The results showed that among the three compounds, ODH exhibited the most potent antibacterial activity.

Antimicrobial activity of PVP from an Antarctic bacterium, Janthinobacterium sp. Ant5-2, on multi-drug and methicillin resistant Staphylococcus aureus

Multiple drug resistant(MDR)and methicillin-resistant Staphylococcus aureus(MRSA)have become increasingly prevalent as a community acquired infection.As a result limited treatment options are available with conventional synthetic antibiotics.Bioprospecting natural products with potent antimicrobial activity show promise for developing new drugs against this pathogen.In this study,we have investigated the antimicrobial activity of a purple violet pigment(PVP)from an Antarctic bacterium,Janthinobacterium sp.Ant5-2 on 15 clinical MDR and MRSA strains.The colorimetric resazurin assay was employed to determine the minimum inhibitory concentration(MIC90)of PVP against MDR and MRSA.The MIC90 ranged between 1.57μg/mL and 3.13μg/mL,which are significantly lower than many antimicrobials tested from natural sources against this pathogen.The spectrophotometrically determined growth analysis and total microscopic counts using Live/dead®BacLight™fluorescent stain exhibited a steady decrease in viability of both MDR and MRSA cultures following treatment with PVP at the MIC levels.In silico predictive molecular docking study revealed that PVP could be a DNA-targeting minor groove binding antimicrobial compound.The continued development of novel antimicrobials derived from natural sources with the combination of a suite of conventional antibiotics could stem the rising pandemic of MDR and MRSA along with other deadly microbial pathogens.

Antimicrobial Effects of Berries on Listeria monocytogenes

The purpose of this study was to first evaluate the antimicrobial effects of powder and extracts of berries (rose-hip, aronia, sea buckthorn and hawthorn) on the development of antibiotic-resistant L. monocitogenes. Listeria monocytogenes is considered one of the most important pathogens responsible for food-borne infection. Antimicrobial properties were evaluated using the standard Kirby-Bauer disk diffusion method. Bacterial inactivation networks were determined and compared, as well as the possibility of using powders and extracts of berries to control the risk of Listeria monocytogees infestation in the milk and dairy industry as well as in the meat industry. The effect of pH (4.78 - 4.43) and water activity (0.90 - 0.80) on the relationship between optical density (OD) at 600 nm and the plate count (CFU ml-1) was investigated for Listeria monocytogenes. It was determined Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) of berries for L. monocytogenes. The most relevant bacteriostatic and bactericidal effect on L. monocytogenes in the tested berries demonstrated sea buckthorn and rosehip.

Syntheses of Coordination Compounds of 2-Amino-3-Methylbutanoic Acid Their Mixed Ligand Complexes and Antibacterial Activities

Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However, for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.

Identity and Safety of a Novel <i>Aurantiochytrium sp.</i>for Terrestrial Heterotrophic Docosahexaenoic Acid Production

The objective of the studies in this paper was to expand on the published toxicological assessment of Aurantiochytrium limacinum (AURA) with further strain characterization and to investigate the potential for the biomass or extracted oil to have antimicrobial properties or undesirable substances. AURA is being investigated as a novel source of the omega-3 long-chain polyunsaturated fatty acid docosahexaenoic acid (DHA) for enriching foods of animal origin by means of feed supplementation. In the first studies, we provided the 18S rRNA identification of the novel marine isolated thraustochytrid, established the nutritional composition of AURA biomass for application as a food or feed ingredient including proximate analysis and fatty acid profiling, and confirmed the DHA production potential of the strain. We determined through minimum inhibitory concentration (MIC) analysis that the unextracted AURA biomass was safe, showing no antimicrobial influence and no evidence of any deleterious effects of this product or its extracts at concentrations up to 1% w/w on the reference human intestinal bacteria tested. This would indicate that AURA should not stimulate selective pressure on the commensal microbiota and is therefore unlikely to aid development of antimicrobial resistance and the concomitant harm to humans and animals. Further analysis revealed that the AURA biomass produced through industrial heterotrophic fermentation was free from undesirables;toxic marine microalgal metabolites, heavy metals, pesticides, microbial contaminants, and mycotoxins. Including heterotrophically-grown AURA in food or feed, up to 1% w/w, is a safe and environmentally beneficial strategy for DHA supplementation.

Antimicrobial Susceptibilities of Salmonella spp. Isolated from Chicken Meat Samples

The aim of this study was to determine presence of Salmonella spp. in chicken meat samples collected from Ankara, Turkey and determine the susceptibility of the Salmonella isolates to some antimicrobial agents. For this purpose, 127 chicken samples were collected from local markets. Investigation of Salmonella was done according to horizontal method, the guidelines of the method recommended by International Standards Organization （ISO）. Antimicrobial susceptibilities of Salmonella spp. was performed with microdilution method according to the guidelines of CLSI M100-SI8. Ampicillin, gentamicin sulphate, ofloxacin, levofloxacin, ciprofloxacin, enrofloxacin, tetracycline, ceftriaxon, amoxicillin/clavulanic acid and trimethoprim/sulfamethoxazole were used in the study. Salmonella spp. was isolated from 5 （3.94%） of the 127 chicken meat samples. Although our findings are not within Turkish Food Codex （TFC） values, lower number of samples that involve Salmonella spp. indicates an improvement in the hygienic conditions in Turkey. Among 5 isolates, one isolate was sensitive to all antimicrobial agents tested. 2 isolates exhibited multidrug resistance. Successfully, all the isolates were sensitive to quinolones as a good result in spite of the reported reduced susceptibility from different regions of the world. However, this study should be improved with more chicken samples and Salmonella spp. isolate numbers to support these results.

<i>In Vitro</i>Susceptibility of Dermatophytes to Anti-Fungal Drugs and Aqueous <i>Acacia nilotica</i>Leaf Extract in Lagos, Nigeria

Dermatophytes were earlier reported to respond well to anti-fungal agents;however, an upsurge in resistance with the high cost of these agents increased the use of medicinal plants for treatment. This study investigated the sensitivity pattern of dermatophytes to oral anti-fungal drugs and aqueous leaf extract of the plant, Acacia nilotica. The extract was tested against seven strains of dermatophytes Arthroderma otae, Trichophyton interdigitale, Trichophyton mentagrophyte, Microsporum ferrugineum, Arthroderma vespertilii, Arthroderma quadrifidum, and Arthroderma multifidum, previously isolated from diabetic patients. The minimum inhibitory and fungicidal concentrations of the plant extracts and the standard antifungal agents were evaluated using modifications of the broth macro dilution method of the National Committee for Clinical Laboratory Standards M38-A2 protocol. There was a significant difference in the Minimum Inhibitory concentrations (MIC) of the dermatophytes to the three antifungal drugs tested (p < 0.001). The dermatophytes were mostly susceptible to itraconazole followed by Nystatin. All the dermatophytes tested were resistant to griseofulvin. Acacia nilotica had an inhibitory effect on all the dermatophytes tested, and showed anti-fungal activity in a dose-dependent relationship between 0.625 - 1.25 mg/ml. Though the inhibitions of the dermatophytes were significantly higher with the standard anti-fungal drugs as compared to the plant extract (p < 0.001);however, the dermatophyte, Arthroderma quadrifidum, which was resistant to all the anti-fungal drugs, had the highest inhibition with A. nilotica. Some circulating dermatophyte strains in Nigeria are griseofulvin and/or itraconazole resistant which may influence the spread of infection and A. nilotica aqueous leaf extract showed a strong anti-dermatophytic activity.

Antibacterial Activity of Honey from Wild Species of Stingless Bees;<i>Plebenia hylderbrandii</i>and <i>Meliponula bocandei</i>

One of the serious problems the world is facing today is the antimicrobial resistance on available antibiotics by most bacterial pathogens and the rising cost of finding effective antimicrobial agents. In recent years, efforts to find new drugs especially from natural sources have been boosted by the demand for an effective cure for infectious diseases. Only the antibacterial activity of apis mellifera honey and not stingless bee honey from western Kenya has been reported. This study was therefore carried out to determine the effect of Plebenia hylderbrandii and Meliponula bocandei honey samples on the growth of control;sensitive cases of Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923). Different honey concentrations (1.18% - 17.65% v/v) of the two samples were tested against the two micro-organisms. The samples were screened for their antibacterial potential against Escherichia coli and Staphylococcus aureus by agar well dilution method. The Partial inhibitory concentration (PIC), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined by in vitro method. The inhibitory effect of Plebenia hylderbrandii honey on E. coli and S. aureus growth was apparent at concentrations 3.53% and 1.76% (v/v) respectively. On the other hand, the inhibitory effect of Meliponula bocandei honey on S. aureus growth was at concentration 16.47% (v/v). Plebenia hylderbrandii honey had bactericidal effect on both E. coli and S. aureus at concentrations 4.71% and 2.35% (v/v) respectively. However, Meliponula bocandei honey exerted bactericidal effect on S. aureus only at 16.47% (v/v) concentration. Plebenia hylderbrandii honey had higher antibacterial potency and can be a potential source of antibacterial substances. Moreover, the honeys tested in this study showed great antibacterial potential for S. aureus.

Callogenesis and Antibacterial Activity of Balanites aegyptiaca

B. aegyptiaca, it is a species of economic and cultural importance in various countries, with diverse uses that include: medicinal, charcoal, pesticides and forage and in vitro callus production is important to have many applications in both basic and industrial research on this specie. For the induction of callus, B. aegyptica seed cotyledons were surface sterilized with 90% ethanol for 1 minute and cultivated in MS media supplemented with 2,4-D, BAP and NAA. Both the callus and seed were collected and dried in an oven at 40°C - 45°C. Cotyledon’s seed and callus were grounded into the powdered form using mortar and pestle and stored at room temperature for further use. Five grams (5 g) each of the powder were mixed with 50 ml of the solvents: methanol and n-hexane (1:10) w/v, agitated vigorously and kept on an orbital shaker at 150 rpm for 24 h, then filtered. The extracts of the plant sample were evaluated in agar dilution method which was used to determine the MIC and MBC of the extracts. The auxin NAA in low concentrations (0.5 mg/L) in the presence of a dose of 0.5 mg/L of the cytokinin BAP induced 100% callus formation. The 50 and 100 mg/ml methanolic extracts were more effective than the n-hexane extracts for both the gram-positive and gram-negative bacteria. By callus extracts under 100 and 50 mg/ml reveals that methanolic extracts of callus had the highest zone of inhibition. An effective protocol for callus induction has been developed that can use for germplasm conservation or for genetic engineering. Evidence from the present study revealed both extracts possess strong broad-spectrum antibacterial effect. Therefore, methanolic extract of seed kernel callus of B. aegyptiaca can be utilized as a new source of broad spectrum antibacterial drugs for effective control of bacteria related diseases.