Standard Antifungal Drug Research Articles

Efficacy of Copper Charged Water against Candida albicans

Copper has been proved to be an effective antimicrobial agent with added advantage of being harmless to human at low concentration. This research has been done to assess the affectivity of copper along with some other metals, on an opportunistic pathogen Candida albicans. Copper was found to be the most potent of all. Metallic copper was then compared with copper charged water for its action on the same fungus. Along with this brilliant metal, its water also has antifungal action even better than a standard antifungal drug, fluconazole, at its MIC. Upon introduced in media, copper charged water shows changes in Candida growth pattern.

In-vitro antimicrobial efficacy of certian herbal seeds essential oils against important poultry microbes

Two in-vitro experiments were conducted to evaluate the antibacterial, antifungal and antiviral properties of essential oil of herbal seeds. In-vitro antimicrobial properties of essential oils of phytobiotics was determined by disc diffusion method against Escherichia coli, Staphylococcus aureus, Pasteurella multocida and Salmonella typhi and two fungi namely Aspergillus fumigatus and Candida albicans. Thyme oil had statistically similar or significantly (P<0.05) higher inhibition zone against all the bacterial and fungal species compared to standard antibiotic, chloramphenicol or antifungal drug, nystatin. Fenugreek oil was not found to be active against microbes compared to control. Fennel and cumin oils had statistically similar or significantly (P<0.05) higher inhibition zone against all microbes except Staphylococcus aureus and Salmonella typhi compared to control. Antiviral activity of essential oils was determined by anti-NDV assay against New Castle disease virus (LaSota). The results indicated that essential oils of herbal seeds do not possess antiviral activity against NDV LaSota virus at 1mg/ml concentration.

Mixed bismuth(III) complexes with sulfur donor ligands

Mixed bismuth(III) bis(O-alkyldithiocarbonato-S,S′) complexes with dialkyldithiocarbamates have been obtained by two-step one-pot synthesis. These complexes have been characterized by physicochemical (molecular mass determination, melting point and elemental analysis), spectral (UV–Visible, FTIR, far-IR, 1H and 13C NMR), thermal and powder X-ray diffraction studies. It has been observed that both the dithiolato ligands are coordinated via an anisobidentate mode to the central metal atom. Powder XRD analysis indicates that all the complexes are in nanoranged crystallite size (3.1–8.8 nm) and have adopted monoclinic crystal system. Bismuth sulfide (Bi2S3) nanoparticles have been obtained upon thermal decomposition of these complexes. The preparation of bismuth sulfide (Bi2S3) nanoparticles was further confirmed by the help of EDAX analysis of the thermal degradation product. All the synthesized complexes exhibited greater antimicrobial activity than standard antibacterial drug chloramphenicol and antifungal drug terbinafine.

English

The emergence of multi-drug resistant microbes necessitates a continuous search for newer, effective antimicrobial agents. The crude methanol leaf extract of Vernonia glaberrima was screened for its antimicrobial activity against pathogenic microorganisms including Methicillin resistant Staphylococcus aureus, Vancomycin resistant enterococci, Listeria monocytogenes, Staphylococcusau reus, Helicobacter pylori, Campylobacter fetus, Proteus vulgaris, Pseudomonas fluorescens, Candida tropicalis and Candida stellatoidea using agar diffusion and broth dilution methods. The result of the susceptibility test showed the extract (400μg) inhibited the growth of Methicillin-resistance S. aureus, Vancomycin resistant enterococci, S. aureus, H. pylori, P. fluorescens and C. stellatoidea with mean zone of inhibition range of 18 to 29 mm; the most susceptible organism was S. aureus (29 mm) and the least was the fungus, C. stellatoidea  (18 mm). No activity was observed against L. monocytogenes, C. fetus, P. vulgaris and C. tropicalis. Sparfloxacin (5µg/ml) the standard antibacterial drug, had inhibitory activity against all the test organisms except H. pylori, P. flourescens, C. tropicalis and C. stellatoidea while the standard anti-fungal drug, Fluconazole (5µg/ml), showed activity only on the two fungi species, C. tropicalis and C. stellatoidea. The Minimum inhibitory concentration (MIC) and the minimum bactericidal/fungicidal concentration (MBC/MFC) ranges for the extract were 5 to 20 mg/ml and 10 to 40 mg/ml, respectively. The results of this study suggest that the methanol leaf extract of V. glaberrima contains bioactive principles that have good antibacterial and antifungal activity, validating the antimicrobial use of the plant in traditional medicine.   Key words: Vernonia glaberrima, extract, antimicrobial, MIC, MBC, evaluation.

Synthesis and Antimicrobial Activity of Some 2-Amino-4-(7- Substituted/Unsubstituted Coumarin-3-yl)-6-(Chlorosubstitutedphenyl) Pyrimidines

Purpose: To prepare some 2-amino 4- (7-substituted/unsubstitutedcoumarin-3-yl)-6-(chlorosubstitute dphenyl) pyrimidines as antimicrobial agents.Methods: Some 2-amino-4-(7-substituted/unsubstitutedcoumarin-3-yl)-6-(chlorosubstitutedphenyl) pyrimidines were prepared by reacting 3-chlorosubstitutedphenyl-1-(7-substituted/unsubstituted coumarin 3-yl)prop-2-ene-1-ones with guanidine carbonate. The chemical structures of the synthesized compounds were elucidated by Fourier transform infra-red spectroscopy (FTIR), 1H-nuclear magnetic resonance (1H-NMR), mass spectrometry and elemental analysis. The synthesized compounds were investigated for their antimicrobial activity against four bacteria and five fungi by serial plate dilution method using ofloxacin and ketoconazole as reference antimicrobial drugs, respectively, and their minimum inhibitory concentrations (MICs) were determined.Results: Compounds 1 (p < 0.0001), 2 (p < 0.0001), 6 (p < 0.0001) and 8 (p < 0.0001) were the most active antibacterial agents among the synthesized compounds compared to control and standard agents. Structure-activity relationship revealed that substitution of chlorine atoms at 2- and 6- positions of the phenyl ring are critical for antibacterial activity in the case of dichlorophenyl derivatives, while for monochlorophenyl derivatives, the positions 2 and 4 of the phenyl ring were critical for antibacterial activity. None of the compounds exhibited comparable antifungal activity to the standard antifungal drug, ketoconazole, even at high concentrations.Conclusion: It is evident that the synthesized compounds are relatively very active antibacterial agents but are weak antifungal agents. However, these compounds need further evaluation of their antibacterial activity against other bacterial strains to ascertain their broad spectrum antibacterial activity.Keywords: Pyrimidine, Coumarin, Antibacterial, Antifungal, Structure-activity Relationship

Mixed Ligand-Cu(II) Complexes as Antimicrobial Agents: Preparation and Spectroscopic Studies

Three mixed ligand-complexes of Cu(II) were prepared using Schiff base ligands and characterized using analytical and physical techniques. Antimicrobial activities of the above synthesized Cu(II) complexes were performed against selected species of bacteria and fungi. All the three Cu(II) complexes under study showed good antimicrobial activity which was compared with standard antibacterial and antifungal drug.

Synthesis, antimicrobial evaluation, and molecular docking studies of new tetrahydrocarbazole derivatives

New derivatives bearing 6,7,8,9-tetrahydro-5H-carbazole moiety functionalized with different side chains and/or heterocycles were synthesized and evaluated for their in vitro antibacterial and antifungal activities. The reaction of the starting acid hydrazide 3 with benzoyl chloride yielded the corresponding compound 4. A series of Schiff’s bases 5a–d were synthesized by the treatment of 3 with different aromatic or heterocyclic aldehydes. Furthermore, acid hydrazide 3 was refluxed with various acid anhydrides to give the derivatives 6a–c. Esterification of 3 with ethyl chloroformate produced the corresponding ester analogue 7 which was further reacted with hydrazine hydrate to give the carbonohydrazide derivative 8. Also, new derivatives carrying tetrahydrocarbazol-benzohydrazide core in conjugation with various heterocyclic ring systems: 5-aminopyrazole, thiadiazole oxadiazole, 1,3,4-triazol-2-thione, and triazolo[3,4-b]thiadiazole 9, 10, 13, 14, 15, 16, and 17, respectively, were synthesized. Antimicrobial evaluation exhibited that most of the synthesized compounds produced promising antibacterial and moderate to weak antifungal activities when compared with ciprofloxacin and ketoconazole as standard antibacterial and antifungal drugs. Dual efficient potency was gained by compounds 6a, 6c, and 12. A molecular docking study of some of the compounds was carried out inside the active site of DNA gyrase protein.

Antifungal Activity of Tamarix aphylla (L.) Karst. Stem-bark Extract Against Some Pathogenic Fungi

The largest identified, Tamarix aphylla (L.) Karst. belonging to family Tamaricaceae is traditionally an important plant used to cure various ailments. Crude ethanolic extracts at concentrations of 2000 ppm, 1000 ppm and 500 ppm were tested against six pathogenic fungi, i.e. Aspergillus flavus, A. fumigatus, A. niger, Fusarium oxysporum, Penicillium notatum and Saccharomyces cerevisiae using five different solvents, e.g. acetone, chloroform, distilled water (DW), ethanol and methanol. Percent of inhibition in fungal growth was recorded. The standard antifungal synthetic drug, Terbinafine, was used in different concentrations mixed with distilled water against different test fungi. Terbinafine completely inhibited the growth of A. flavus, A. fumigatus, A. niger, F. oxysporum, P. notatum and S. cerevisiae with the concentrations of 65±0.58, 72±1.00, 70±1.15, 59±1.00, 60±0.58 and 80±0.58 (µg/ml of PDA medium), respectively. Chloroform was considered to be the most effective solvent preventing 97.68±0.58% growth of F. oxysporum, 9.37±0.33% in A. niger, 92.68±3.33% in S. cerevisiae, 91.46±2.08% in A. fumigatus, 88.48±0.88% in A. flavus and 87.95±1.15% in P. notatum. The obtained results were compared with negative control and most of the results were found to be highly significant (p=0.000). Overall, our results suggest that T. aphylla stem-bark extract illustrated maximum percent inhibition when extracted with chloroform followed by ethanol, acetone, methanol and distilled water.

Anti-candidal activity of homoeopathic drugs: An in-vitro evaluation

Background: Candida albicans is an opportunistic pathogenic fungus accounting for up to 75% of all candidal infections in human beings. Generally Candida grow and survive as commensals but slight modification of the host defense system can transform Candida albicans into a pathogen. Materials and Methods: Samples collected from the oral cavity and tongue of the patients suspected of suffering from oral candidiasis were incubated for growth of Candida. Fermentation and assimilation test confirmed the species as Candida albicans. Disc method was used to assess the in-vitro anti-candidal effect of few homoeopathic drugs in 30 and 200 potencies against human pathogenic Candida albicans under in-vitro conditions and compared with standard antifungal drug ketoconazole (control), rectified spirit (control/vehicle) and distilled water (vehicle) by inhibition zone technique. Results: Homeopathic drugs namely Acid benzoicum, Apis mellifica, Kali iodatum, Mezereum, Petroleum, Sulphur, Tellurium, Sulphur iodatum, Graphites, Sepia, Silicea and Thuja occidentalis in 30 and 200 potencies were tested against Candida albicans. Mezereum in 200 and 30 potency showed maximum inhibition of growth of Candida albicans followed by Kali iodatum 200 while Kali iodatum 30 and Petroleum 30 had minimum inhibition.Conclusion: The results of these experiments support the concept of evidence based medicine depicting that homoeopathic medicines not only work in in-vivo but are equally effective in in-vitro conditions having definite inhibitory activity against Candida albicans.

Synthesis, characterization and fungicidal activity of binary and ternary metal(II) complexes derived from 4,4′-((4-nitro-1,2-phenylene) bis(azanylylidene))bis(3-(hydroxyimino)pentan-2-one)

Ternary copper(II) and binary copper(II), nickel(II) and cobalt(II) complexes derived from 4,4′-((4-nitro-1,2-phenylene)bis(azanylylidene))bis(3-(hydroxyimino)pentan-2-one) (H2L) were synthesized and characterized by elemental and thermal analyses, IR, UV–Vis. and 1H NMR spectroscopy, conductivity and magnetic moments measurements. The analytical and spectral data showed that, the ligand acts as dibasic tetradentate or dibasic hexadentate bonding to the metal ion via the two-imine nitrogen, two nitrogen and/or oximato oxygen atoms of deprotonated oxime groups forming five and/or six rings including the metal ions. The complexes adopt either tetragonal distorted octahedral or square planar geometry around metal ions. The ESR spectra of the solid copper(II) complexes are characteristic to d9 configuration and having an axial symmetry type of a d(x2−y2) ground state. The g values confirmed the geometry is elongated tetragonal octahedral geometry with considerably ionic or covalent environment. The antifungal biological activity of the prepared compounds was studied using well diffusion method. The obtained results showed that, the ligand is biologically inactive while its metal complexes were more potent fungicides than the ligand and standard antifungal drug (Amphotericin B).

In vitro combination therapy using low dose clotrimazole and photodynamic therapy leads to enhanced killing of the dermatophyte Trichophyton rubrum.

BackgroundSuperficial infections of the skin and mucous membranes caused by dermatophyte fungi are amongst the most common and challenging infections to treat. Previously we demonstrated the phototoxic effects of photodynamic therapy (PDT) towards Trichophyton rubrum, using a green laser to photoactivate Rose Bengal (RB). The aim of this study was to evaluate whether we could; (1) achieve a similar effect using an inexpensive light-emitting diode (LED) to photoactivate RB and (2) to evaluate whether our PDT regime could be combined with standard antifungal drug therapy and increase its effectiveness.MethodsWe designed and built our own inexpensive green (530 nm) LED source and tested its efficacy as part our RB-PDT regime in vitro against T. rubrum. We also examined the potential benefits of incorporating PDT as part of combination therapy and whether the order in which this was done had an impact. First we subjected spore suspensions to sub-inhibitory concentrations of a number of antifungal agents (CLT, MCZ and TRB) for 72 hours followed by RB-PDT. Secondly we subjected spore suspensions to sub-inhibitory PDT followed by drug treatment and evaluated if there were any changes to the minimum inhibitory concentrations (MICs) of the drugs tested.ResultsThe optimal conditions for photoinactivation of T. rubrum using RB-PDT alone were 140 μM of RB and 24 J/cm2 of LED (equating to a 30-minute exposure). These parameters also caused a 100% reduction in the viability of the pathogenic yeast Candida albicans and the model fungus Saccharomyces cerevisiae. By combining our RB-PDT regime as an adjunct to antifungal drugs we were able to dramatically reduce the exposure times. Treatment of spore suspensions using a sub-inhibitory dose of clotrimazole (CLT) followed by RB-PDT, this order was critical, significantly reduced the exposure times required to achieve 100% inhibition of T. rubrum to 15 minutes as compared to RB-PDT alone.ConclusionsThe combination of antifungal drug and RB-PDT represents an attractive alternative to the current antifungal therapies used to treat superficial fungal diseases. Our approach has the potential to reduce treatment times and drug dosages which can also reduce drug toxicity and improve patient compliance.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-014-0261-z) contains supplementary material, which is available to authorized users.

Anti-Dermatophytic Activity of Garlic (<i>Allium sativum</i>) Extracts on some Dermatophytic Fungi

Dermatophytic infection is a common infection that constitutes public health problem among children. Anti dermatophytic activity of aqueous, ethanolic and methanolic extracts of garlic (Allium sativum) was investigated against isolates of dermatophytic fungi obtained from sixty primary school children in Aba. The well in agar diffusion technique was used to determine the sensitivity patterns of the test organisms. The results were compared with the activity of a known antifungal drug nystatin. The isolates included Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum gypseum, Trichophyton verrucosum and Epidermophyton floccosum. The result of the antifungal activity of garlic showed high but varied levels of antifungal effectiveness on the different species of the dermatophytes at four different concentrations of 12.5 %, 25 %, 50 % and 100 % used. T. rubrum was the most susceptible followed by M. gypseum, T. mentagrophytes, T. verrucosum and E. floccosum respectivey. The diameter zones of inhibition exhibited by the extracts against test fungal species ranged between 4.50 mm and 30.67 mm. Further purification and extraction of active principle of garlic would give an antidermatophytic activity comparable to standard antifungal drugs

Synthesis and Antimicrobial Studies of Pyrimidine Pyrazole Heterocycles

Prompted from the diversity of the wider use and being an integral part of genetic material, an effort was made to synthesize pyrimidine pyrazole derivatives of pharmaceutical interest by oxidative cyclization of chalcones with satisfactory yield and purity. A novel series of 1,3-dimethyl-6-hydroxy-2,4-dioxo-5-(1′-phenyl-3′-aryl-1H-pyrazol-5′-yl)-1,2,3,4-tetrahydropyrimidines (5a–d) and 1,3-diaryl-6-hydroxy-4-oxo-2-thioxo-5-(1′-phenyl-3′-aryl-1H-pyrazol-5′-yl)-1,2,3,4-tetrahydropyrimidines (5e–l) has been synthesized. The structures of these compounds were established on the basis of FT-IR, 1H NMR, 13C NMR, and mass spectral analysis. All the synthesized compounds were screened for their antimicrobial activity against bacteria and fungi. Among all the compounds, 5g was found to be the most active as its MIC was 31.25 µg/mL against S. aureus and B. cereus. The compounds 5h, 5c, and 5e also possess antibacterial activity with MIC values as 62.50, 125.00, and 500.00 µg/mL, respectively. The compounds 5c and 5j were found to have antifungal activity against Aspergillus spp. As antifungal drugs lag behind the antibacterial drugs, therefore we tried in vitro combination of these two compounds with standard antifungal drugs (polyene and azole) against Aspergillus spp. The combination of ketoconazole with 5c and 5j showed synergy at 1 : 8 (6.25 : 50.00 µg/mL) and 1 : 4 (25 : 100 µg/mL) against A. fumigatus (ITCC 4517) and A. fumigatus (VPCI 190/96), respectively.

Anti-Dermatophytic Activity of Garlic (<i>Allium sativum</i>) Extracts on some Dermatophytic Fungi

Dermatophytic infection is a common infection that constitutes public health problem among children. Anti dermatophytic activity of aqueous, ethanolic and methanolic extracts of garlic (Allium sativum) was investigated against isolates of dermatophytic fungi obtained from sixty primary school children in Aba. The well in agar diffusion technique was used to determine the sensitivity patterns of the test organisms. The results were compared with the activity of a known antifungal drug nystatin. The isolates included Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum gypseum, Trichophyton verrucosum and Epidermophyton floccosum. The result of the antifungal activity of garlic showed high but varied levels of antifungal effectiveness on the different species of the dermatophytes at four different concentrations of 12.5 %, 25 %, 50 % and 100 % used. T. rubrum was the most susceptible followed by M. gypseum, T. mentagrophytes, T. verrucosum and E. floccosum respectivey. The diameter zones of inhibition exhibited by the extracts against test fungal species ranged between 4.50 mm and 30.67 mm. Further purification and extraction of active principle of garlic would give an antidermatophytic activity comparable to standard antifungal drugs

In-vitro antidermatophytic activity of essential oil of Psidium guajava (Linn.)

Dermatophyte with the ability to digest keratine invade and therve on keratinized of human and animals. In the present study, the activity of essential oil of Psidium guajava (Linn.) was evaluated against four selected dermatophytes, namely Microsporiumcanis, Trichophytomruburum, T. verrucossum, T. tonsurans. Dermatophyteswere isolated with the infected skin, scalp, nail and genital organs of patients from districts hospital, Bareilly. Griseofulvin was used as a standard antifungal drug against the test dermatophytes. Oil was extracted through clevenger’s apparatus. Maximum inhibition zone was reported 69 mm against T. verrucossum followed by 60 mm Trichophytomruburum, 48 mm Trichophytomruburum and 45mm Microsporiumcanis. All five concentrations of oil showed excellent inhibitory effect against all test dermatophytes as compared to standard antifungal used.

In vitro anti-Candida activity and single crystal X-ray structure of ({(1E)-[3-(1H-imidazol-1-yl)-1-phenylpropylidene]amino}oxy)(4-nitrophenyl)methanone

Synthesis, characterization, and anti-Candida activity of ({(E)-[3-(1H-imidazol-1-yl)-1-phenylpropylidene]amino}oxy)(4-nitrophenyl)methanone (4) are reported. Compound 4 showed anti-Candida albicans activity (MIC = 0.6862 µmol/mL) being nearly 5-fold more potent than the gold standard antifungal drug, fluconazole (MIC ˃ 3.265 µmol/mL), on the clinical isolates of Candida albicans. Single crystal X-ray structure of the title compound 4 confirmed its assigned (E)-configuration. The compound crystallizes in the triclinic, P-1 (no. 2), a = 6.4633 (1) Å, b = 11.1063 (2) Å, c = 12.9872 (2) Å, α = 67.650 (1)°, β = 86.415 (1)°, γ = 86.776 (1)°, V = 860.01 (3)Å3, Z = 2, R(F) = 0.046, wR(F2) = 0.139, T = 296 K. The crystal structure is stabilized by weak intermolecular C—H•••O hydrogen interactions.

EVALUATION OF ANTIBACTERIAL, ANTIFUNGAL, ENZYME INHIBITION AND HEMOLYTIC ACTIVITIES OF CARYOPTERIS ODORATA FRACTIONS

The purpose o f this study was to explore the antibacter ial, antifungal, enzyme inhibition and hemolytic activities of various fractions of Caryopteris odorata (Ham. Ex Roxb.) . The methanolic extract of plant was dissolved in distilled water and partitioned with n - hexane, chloroform, ethyl acetate and n - butanol sequentially. Antibacterial activity was checked against Staphylococcus aureus , Bacillus subtilis , Pasturella multocida and Escherichia coli by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Polar fracti on s showed good antibacterial potential against these strains. These fractions also showed good MIC values. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the dis c diffusion method using fluconazole, a standard antifungal drug, as positive control. E thyl acetate fraction was found active against A. niger and G. lucidum while chloroform and n - butanol fraction s were active against A. flavus. Enzyme inhibition studies were performed against four enzymes i.e. α - glucosidase , butyrylcholinesterase, acetylcholinesterase and lipoxygenase. E thyl acetate and n - butanol soluble fraction exhibited good activity against α - glucosidase with IC 50 values 79.77 ± 0.97 and 82.77 ± 0.88 respectively. Chloroform soluble fraction showed moderate activity against butyrylcholinesterase ( IC 50 69.71 ± 0.95) while chloroform and ethyl acetate soluble fraction exhibited good activity against the lipoxygenase with IC 50 values 65.28 ± 0.57 and 78.71 ± 0.69 respectively. Ethyl acetate frac tion showed high toxicity i.e. 85.14 ± 0.83 %.

In Vitro Screening of 10 Edible Thai Plants for Potential Antifungal Properties

Growing rates of fungal infections and increasing resistance against standard antifungal drugs can cause serious health problems. There is, therefore, increasing interest in the potential use of medicinal plants as novel antifungal agents. This study investigates the antifungal properties of crude plant extracts from ten medicinal plant species. Crude samples were extracted using the hot water extraction process. The minimum inhibitory concentrations (MIC) and diameter zone of inhibition were determined in each extract against ten fungal strains, and fluconazole was used as a positive control. The cytotoxicity of crude extracts on in vitro human skin fibroblast (HSF) cell models was determined by MTT assay. Of the ten crude extracts, Psidium guajava L. exhibited the highest antifungal activity, diameter zone of inhibition, and percentage HSF cell viability. Although all extracts exhibited antifungal activity, Psidium guajava L. had the greatest potential for developing antifungal treatments.

Chlorinated Imidazole Complexes as Potent Antifungal Agents

dichloroimidazole (DCI) was synthesized and characterized using spectroscopic methods. The compound and its complexes did not show any significant antibacterial activity against Streptococcus pyogenes, Staphylococcus aureus, Pseudomonas aeruginosa and Proteus spp, when compared with the good activity shown by imidazole which is its precursor compound. Imidazole however showed complete inactivity against the fungi strains Aspergillus spp, Candida spp and Trichophyton spp. These fungi were very sensitive to DCI with further sensitivity shown to the Cr 3+ and Co 2+ complexes of the compound. These two complexes of DCI were also more active than the standard antifungal drug ketoconazole in inhibiting the growth of these fungi making them very potent compounds in the search for antifungal agents.

In vitro antimicrobial activities of anthrones from the leaf latex of Aloe sinana Reynolds

Background: Aloe sinana Reynolds is endemic to Ethiopia where its leaf latex is traditionally used in and around the town of Debre Sina and other central highlands of the country for the treatment of various illnesses, including wound, snake bite and malaria. However, despite its use in traditional medicine, to date, there appears to have been no chemical or biological studies published on this plant. Aim: The aim of this study was to investigate the leaf latex of A. sinana for its antibacterial and antifungal activities, and to isolate and characterise the compounds that are responsible for the antimicrobial effect of the latex. Materials and Methods: The latex was extracted with methanol. Isolation of compounds was achieved by repeated preparative TLC, and spectroscopic techniques including 1H, 13C‑NMR and MS were used for characterisation of the isolated compounds. Antimicrobial activity tests were performed against 21 bacterial and 4 fungal pathogens using the disc diffusion method. Results and Conclusion: Three compounds isolated from the leaf latex were identified as the anthrones, aloin, aloinoside and microdontin. Among the isolated compounds, aloinoside and microdontin were found to possess comparable activity (MIC 5 μg/ml) with that of ciprofloxacin against several Gram‑negative bacterial strains and Staphylococcus aureus. Additionally, microdontin showed potent and comparable activity with the standard antifungal drug griseofulvin against Penicillum spp. These findings support the traditional uses of the plant for the treatment of various infections and wound. Key words: Aloe sinana, anthrones, antibacterial, antifungal, disc diffusion, latex