Antifugal Activity Research Articles

In Vitro Antifungal Efficacy of Allium Cepa And Allium Sativum: A Comparative Study with Commercial Drugs

The in vitro activities of water, methanol, acetone, ethanol, and chloroform extracts of garlic (Allium sativum) and Onions (Allium cepa) were investigated. For comparison, activities of commercially sold antifungals viz Nystatin, Fulcin, and Cotrimoxazole against Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Penicillium spp, Trichophyton schoeleinii, and Neurospora clasa were also investigated. The largest zone of inhibition was exerted by the ethanol and water extracts of garlic (Allium sativum) against Aspergillus niger, A. fumigatus, T. Schoeleilnii, and penicillium spp. The antifugal activity of onions was less marked while its water extracts showed no activity. The lack of inhibition on Neurospora clasa was conspicuous for both the garlic (Allium sativum) and Onions (Allium cepa) extracts. The commercial drugs were significantly more active against the tested fungi (MIC range 1.56-50ug/ml). Fulcin showed more activity than the rest of the commercial drugs tested. The activities of fulcrum for all the fungal species far surpassed those of nystatin and were even superior to those of Cotrimoxazole on Aspergillus niger and Aspergillus fumigatus. Nystatin showed a higher MIC range of 12.5-50 µg/ml for the tested fungal species. The MFC of the drugs was mostly 2-3 times their MIC values. These results suggest that overall, the fungal species tested showed more sensitivity to the commercially sold antifungals than that of the extracts.

Characterization of Chitinolitic Bacteria from Hermatia illucent Larvae Waste: Antifungal Activity, Hydrolytic Enzyme, and Phosphate-Potassium Solubilization

Hermetia illucens larvae, also known as the black soldier fly larvae, are best known as the decomposers of organic matter. There are many potential microbes found in the feces of BSF larvae. This research aimed to isolate the chitinolytic bacteria from chicken manure maggot waste, identify the antifugal activity, hydrolytic enzyme activity, phosphate and potassium solubilization, and bacterial species through 16S rRNA gene analysis. The initial screening focused on bacteria with chitinolytic ability. Antifungal activity tests were performed against phytopathogenic fungi, Colletotrichum sp. Isolate MKP02 showed the highest activity in inhibiting the growth of Colletotrichum sp. up to 100% and produced protease and cellulase enzymes, along with the ability to solubilize potassium. Furthermore, the potential isolate MKP04, the isolate shows the highest cellulolytic activity with a percentage of 300%. It can inhibit Colletotrichum sp. fungi, as well as having lipase enzyme content, and being able to dissolve potassium. The results of 16S rRNA gene amplification on the two isolates showed that both isolates were close to bacteria of the genus Lysinibacillus and Brevibacterium. This research is expected to provide valuable information about the bacterial content, levels of hydrolytic enzymes, and the ability to solubilize phosphate and potassium in BSF.

Evaluation of Antifungal and Antiproliferative Effects of Two Different Organic Compounds with Cyclobutane Ring

In the modern world, where there is a growing demand for new substances with anticancer and antifungal activities, Schiff bases and phthalimide derivatives, which exhibit a wide diversity of biological activity, have become the focus of new therapeutic research studies. Accordingly, this study examined the anti-proliferative effects of two distinct compounds synthesized by cyclobutane substitution on breast cancer and liver cancer cell lines, which are two major cancer types, were investigated with MTT method and their antifugal activities on C. albicans were evaluated with disk diffusion method. Minimum inhibitory concentrations of the compounds against C. albicans were also determined in the scope of the study. The results revealed that the synthesized Schiff base was more effective on the breast cancer cell line MCF7, whereas the phthalimide-derivative was more effective against the liver cancer cell line Mahlavu. Besides, according to the data related to the antifungal properties of the compounds, it can be inferred that both compounds are suitable for further investigation as potential building blocks for the creation of novel and efficient antifungal medications.

Clotrimazole-Loaded Borneol-Based In Situ Forming Gel as Oral Sprays for Oropharyngeal Candidiasis Therapy.

Oral candidiasis encompasses fungal infections of the tongue and other oral mucosal sites with fungal overgrowth and its invasion of superficial oral tissues. Borneol was assessed in this research as the matrix-forming agent of clotrimazole-loaded in situ forming gel (ISG) comprising clove oil as the co-active agent and N-methyl pyrrolidone (NMP) as a solvent. Their physicochemical properties, including pH, density, viscosity, surface tension, contact angle, water tolerance, gel formation, and drug release/permeation, were determined. Their antimicrobial activities were tested using agar cup diffusion. The pH values of clotrimazole-loaded borneol-based ISGs were in the range of 5.59-6.61, which are close to the pH of 6.8 of saliva. Increasing the borneol content in the formulation slightly decreased the density, surface tension, water tolerance, and spray angle but increased the viscosity and gel formation. The borneol matrix formation from NMP removal promoted a significantly (p < 0.05) higher contact angle of the borneol-loaded ISGs on agarose gel and porcine buccal mucosa than those of all borneol-free solutions. Clotrimazole-loaded ISG containing 40% borneol demonstrated appropriate physicochemical properties and rapid gel formation at microscopic and macroscopic levels. In addition, it prolonged drug release with a maximum flux of 370 µg·cm-2 at 2 days. The borneol matrix generated from this ISG obsentively controlled the drug penetration through the porcine buccal membrane. Most clotrimazole amounts still remained in formulation at the donor part and then the buccal membrane and receiving medium, repectively. Therefore, the borneol matrix extended the drug release and penetration through the buccal membrane efficiently. Some accumulated clotrimazole in tissue should exhibit its potential antifugal activity against microbes invading the host tissue. The other predominant drug release into the saliva of the oral cavity should influence the pathogen of oropharyngeal candidiasis. Clotrimazole-loaded ISG demonstrated efficacious inhibition of growth against S. aureus, E. coli, C. albicans, C. krusei, C. Lusitaniae, and C. tropicalis. Consequently, the clotrimazole-loaded ISG exhibited great potential as a drug delivery system for oropharyngeal candidiasis treatment by localized spraying.

In vitro and in vivo antifungal activity of extracts from Jamaica cherry Muntingia calabura l. leaves

Previous studies on M. calabura (Jamaica cherry) leaves reported the presence of polyphenols, flavonoids, glycosides, and tannins. However, the deep research focus on the antifungal activity of Jamaica cherry leaf extract (JCLE) is still limited. Hence, the current study was conducted on JCLE samples by using various solvents, i.e., 70% ethanol, 70% methanol, and 70% acetone, and then evaluating their antifungal activity. Analytical results showed that JCLE could be used as a natural antifungal potential agent against mold-causing spoilage in fruits. Specifically, the ethanolic extract had a strong inhibition of Colletotrichum gloeosporioides and Lasiodiplodia theobromae. While the methanolic and acetonic extracts prevented sharply the growth of Alternaria alternata and Fusarium equiseti, respectively. Generally, the ethanolic extract was able to inhibit the various mold strains better than the other solvents. Furthermore, the results showed that the percentage inhibition of radial growth (PIRG) of JCLE increased gradually as the concentration increased from 4000 to 40000 mg GAE/kg. The highest data obtained for C. gloeosporioides, A. alternata, F. equiseti, and L. theobromae were 53.29%, 57.03%, 54.81%, and 75.03%, respectively. In vivo experiment, the samples were treated with and without JCLE (the control sample) occuring the black spots caused by C. gloeosporioides on mango’s surface after 21 days and 30 days of storage at 12 ± 2 °C, respectively. Whereas the TSS and TA values of both samples were similar. While the visual appearance of the control was more yellow compared to the samples treated with JCLE. In conclusion, JCLE was able to significantly delay the development of pathogenic mold, though it quite inhibited the maturation of mango fruit. Further studies may be needed to evaluate the phtychemical profile of M. calabura extract to gain a deeper understanding of its antifugal activity.

In vitro antifungal activity of pelgipeptins against human pathogenic fungi and Candida albicans biofilms.

Systemic mycoses have become a major cause of morbidity and mortality, particularly among immunocompromised hosts and long-term hospitalized patients. Conventional antifungal agents are limited because of not only their costs and toxicity but also the rise of resistant strains. Lipopeptides from Paenibacillus species exhibit antimicrobial activity against a wide range of human and plant bacterial pathogens. However, the antifungal potential of these compounds against important human pathogens has not yet been fully evaluated, except for Candida albicans. Paenibacillus elgii produces a family of lipopeptides named pelgipeptins, which are synthesized by a non-ribosomal pathway, such as polymyxin. The present study aimed to evaluate the activity of pelgipeptins produced by P. elgii AC13 against Cryptococcus neoformans, Paracoccidioides brasiliensis, and Candida spp. Pelgipeptins were purified from P. elgii AC13 cultures and characterized by high-performance liquid chromatography (HPLC) and mass spectrometry (MALDI-TOF MS). The in vitro antifugal activity of pelgipeptins was evaluated against C. neoformans H99, P. brasiliensis PB18, C. albicans SC 5314, Candida glabrata ATCC 90030, and C. albicans biofilms. Furthermore, the minimal inhibitory concentration (MIC) was determined according to the CLSI microdilution method. Fluconazole and amphotericin B were also used as a positive control. Pelgipeptins A to D inhibited the formation and development of C. albicans biofilms and presented activity against all tested microorganisms. The minimum inhibitory concentration values ranged from 4 to 64 µg/mL, which are in the same range as fluconazole MICs. These results highlight the potential of pelgipeptins not only as antimicrobials against pathogenic fungi that cause systemic mycoses but also as coating agents to prevent biofilm formation on medical devices.

Screening of Aerial Parts of Kigelia Pinnata for its Antioxidant, Wound Healing and Antimicrobial Activity

The antioxidant activity was performed by DPPH Scavenging activity method and Hydrogen peroxide scavenging activity method. Ascorbic acid was taken as standard in both methods. DPPH and Hydrogen peroxide scavenging activity methods of 100µg/ml extracts shows better % inhibition as compared to control and 50 µg/ml extracts. In DPPH Scavenging activity % inhibition of 100µg/ml methanolic extracts was 60.72% and in Hydrogen peroxide scavenging activity it was found to be 26%. Wound healing activity was performed by Incision wound model and Excision wound model. In incision wound healing model, the tensile strength of the 4% test group and the Neosporin ointment treated group were comparable to each other. Tensile strength of 2% extract ointment showed lesser 3.38 gm/mm2 but significant increase in tensile strength compared to the control group 2.91 gm/mm2. The tensile strength of 4% test group was found to be 3.44 gm/mm2. Thus both concentrations of the extract as well as the standard drug showed a significant increase in tensile strength on the 9th day. In excision models the animals treated with the 4% w/w KPME ointment were shown to healed completely as compared to 2%w/w which was also at the complete healing stage as compared to control treated and the standard drug (Neosporin) treated group. The epithelization period of standard group and treated group was less in comparison with that of simple ointment base treated groups. The percentage of wound contraction was much more with the 4% w/w extract was similar to that of Neosporin treated group. 2%w/w treated group of animals showed significant wound contraction. In antimicrobial activity, both antibacterial and antifungal potentiality was evaluated. In mic of antibacterial methanolic extract of Kigelia pinnta inhibit strains of E.coli and strain of Shigella boyelii, Salmonella aureus and Baccilus subtitis were found to be completely resistant. In mic of antifugal activity, all the fungal strain were inhibited by methanolic extract of Kigelia pinnata. These findings may provide a lead for further investigation of the overall pharmacological aciotns of Kigelia pinnata methanolic extract in more appropriate model.&#x0D; Keywords: Kigelia pinnata, DPPH, Anti-oxidant, DMSO, ANOVA

Daya Hambat Ekstrak Etanol Batang Lakum (Cayratia trifolia (L.) Domin) Terhadap Pertumbuhan Isolat Phytophthora sp. Im5 secara In Vitro

Stem rot disease is caused by one of Phytophthora pathogenic fungi that attacks several types of cultivated plants. The alternative control against Phytophthora attack can be done with the use of natural fungicides. One of the herbs that can be untilized is the ethanol extract of lakum stem (Cayratia trifolia (L.) Domin). The aim of this research is to know the effect of ethanol extract of lakum stem and its secondary metabolite in inhibiting the growth of isolate Phytophthora sp. Im5. The research was conducted for three months starting from October to December 2017. This research used solid dilution method and completely randomized design (CRD) wth 8 levels of treatments, i.e. positive control, negative control, ethanol extract concentration of 5, 10, 15, 20, 25 and 30 mg/ml. The test for secondary metabolite compounds was done by phytochemical screening method. The result showed that the concentration of 30 mg/ml has the biggest antifugal activity with the inhibition percentage of 34.98%. The activity of lakum stem ethanol extract against isolate Phytophthora sp. Im5 was included in moderate catagory. The results of phytochemical screening showed that the ethanol extract of lakum stem contained alkaloid, flavonoid and tannin compounds.

Novel N-(2-bromo-phenyl)-2-hydroxy-benzamide Derivatives with Antifugal Activity

In order to increase the biological activity, some novel molecules, esters, hydrazides, hydrazones of N-(2-bromo-phenyl)-2-hydroxy-benzamide, were obtained in good yields (86-93%), working at 150 �C, 500 W, 7-11 min, under microwave irradiation. All synthesized compounds were characterized using modern physico-chemical methods (FTIR, 1H-NMR, 13C-NMR and elemental analysis). Eight dilutions in dimethyl sulfoxide of these derivatives were tested against two phyto-pathogenic fungi, Fusarium oxysporum, Sclerotinia sclerotiorum and one common yeast, Saccharomyces cerevisiae. The antifungal activity was assessed using disc diffusion method, both negative, pure DMSO, and positive control, nystatin, were used. S. cerevisiae was slightly more sensitive than filamentous fungi, the strongest inhibition, MIC=0.3125g/L, was observed for N-(2-bromo-phenyl)-2-hydroxy-benzamide and N-(2-bromo-phenyl)-2-(4-dimethylamino-benzylidene-hydrazinocarbonylmethoxy)-benzamide. The most active compounds against F. oxysporum and S. sclerotiorum were N-(2-bromo-phenyl)-2-hydroxy-benzamide (MIC= 0.625g/L), N-(2-bromo-phenyl)-2-hydrazinocarbonylmethoxy-benzamide (MIC=1.25g/L) and N-(2-bromo-phenyl)-2-(4-dimethylamino-benzylidene-hydrazinocarbonyl-methoxy)-benzamide (MIC=0.625g/L), N-(2-bromo-phenyl)-2-hydrazinocarbonyl-methoxy-benzamide (MIC=1.25g/L), respectively.

Thermal Properties of Acrylic Resin Denture Base Material Containing Silver Nanoparticle Synthesized from Aqueous Extract of &lt;i&gt;Boesenbergia rotunda&lt;/i&gt;

Silver nanoparticles (AgNPs) were synthesized by bioreduction method using aqueous extracts of Boesenbergia rotunda as reducing and stabilizing agents. Ultraviolet-Visible (UV-Vis) spectrophotometer was utilized to monitor the qualitative formation of AgNPs. The UV-Vis spectrum showed that the spherical AgNPs with diameter of 20-40 nm were formed. The antifugal activity of synthesized AgNPs was investigated using Candida albicans, which was found that the synthesized AgNPs could be used as effective growth inhibitors. The influence of the incorporation of prepared AgNPs on thermal properties of the acrylic denture base material was investigated. Glass transition temperature of filled acrylic resins was studied using the dynamic mechanical analyzer (DMA). The temperature sweeps were performed with tension mode. Thermogravimetry analysis (TGA) was used to examine effect of AgNP concentration and thermocycling (1250, 2500, 5000, and 10000 cycles) on thermal stability of AgNP filled acrylic resin denture base materials. Glass transition temperature (Tg) of the acrylic resins slightly increase with increasing AgNP contents. TGA results indicated that AgNP retarded thermal degradation of acrylic resin denture material, and thermocycling did not affect thermal stability of AgNP filled acrylic resin denture material.

Improving the packaging performance of low-density polyethylene with PCL/nanocellulose/copper(II)oxide barrier layer

A novel double layered hybrid materials, consisting of low density polyethylene (LDPE) base layer and polycaprolactone (PCL) top layer containing surface modified nanocellulose (NC) based nanocomposites in 0.5 and 2 % loadings, were studied in order to design multipurpose packaging material. NC was covalently modified with maleic anhydride (MA) to obtain NCMA, and upon co-precipitation of copper (II) oxide (CuO) on NC and NCMA surface, NC-CuO and NCMA-CuO nanocomposite materials were produced. Two drying methods, conventional and lyophilization, were applied to investigate process influences on the properties of obtained hybrid material. Oxygen transmission rate and antimicrobial activity were determined for all produced hybrid materials. PE-PCL-NCMA-CuO-L2 exhibited the highest antifungal properties, indicating contribution of MA residual group and drying conditions (liophylisation) to achievement of 97 % reduction in cell viability of C. albicans. The sample with 2 % of NCMA-CuO, PE-PCL-NCMA-CuO2, demonstrated to be the most promising material regarding improvement in antibacterial and antifugal activity, as well as 16 % lower value of the oxygen transmission rate in comparison to pure LDPE.

A comparative study of the physicochemical properties and antimicrobial qualities of Abuad moringa soap with conventional medicated soaps

The study was aimed at assessing the physicochemical properties and antimicrobial qualities of 'ABUAD moringa soap', a herbal soap produced with Moringa oleifera leaf by 'ABUAD Farm', Afe Babalola University, Ado Ekiti, Nigeria. The physicochemical properties and antimicrobial qualities of ABUAD moringa soap on some selected bacteria and fungi were evaluated and compared with those of some conventional medicated and herbal soaps commonly used in Nigeria, such as Dettol, Tetmosol, Tura, Septol, Delta and Dudu Osun (herbal), as well as Lux, which serves as a control soap. The results of the physicochemical analyses revealed that all the soaps fall within the pH range of 8.83 and 9.83. All the soaps possess low values of free caustic alkali and detectable free fatty acid, as well as moderate values of total fatty matter. In-vitro antibacterial and antifungal activities of the soaps were investigated against microbial agents commonly found in association with skin infections, using the well-agar diffusion technique. The bacteria tested were Staphylococcus aureus ATCC 25923 and Proteus mirabilis (ATCC 12453), as well as four clinical isolates namely, Escherichia coli, Leutococcus sanguinis, Corynebacterium accolens and Burkholderia cepacia. The fungi were Candida albicans ATCC 10231, Malassezia furfur ATCC 44349, and Cryptococcus neoformans ATCC 23645. All the soaps, with exeption of lux, produced varied degrees of antibacterial activities, but ABUAD Moringa soap and Dudu Osun indicated superior effectiveness against the bacteria tested. Antifugal activities were produced by ABUAD moringa and Dudu Osun soaps only, on the fungi tested. ABUAD Moringa produced significantly higher antifungal activities on Malassezia furfur ATCC 44349 and Candida albicans ATCC 10231 than Dudu Osun, but no significant difference was observed between the two soaps on their activities against Cryptococcus neoformans ATCC 23645. The study showed that ABUAD Moringa soap possesses high therapeutic potentials against agents of bacterial and fungal skin infections.

Synthesis, in vitro evaluation of antibacterial, antifungal and larvicidal activities of pyrazole/pyridine based compounds and their nanocrystalline MS (M = Cu and Cd) derivatives

Methyl 3,5-dimethyl pyrazole-1-dithioate (mdpa) (1), benzyl 3,5-dimethyl pyrazole-1-dithioate (bdpa) (2), 3,5-dimethylpyrazole-1-(5methyl-1H-pyrazol-3-ylmethyl)-1H-pyrazole (3), copper(II)-mdpa (4), copper(II)-bdpa (5), cadmium(II)-mdpa (6), cadmium(II)-bdpa (7), Cu2S nanoparticles (8 and 9) derived from 4 and 5, respectively, CdS nanoparticles (10 and 11) derived from 6 and 7, respectively, were synthesized to screen their antimicrobial activities. Prolonged reaction with CuCl2.2H2O and 3 followed by addition of trace amount of pyridine furnished a crystalline chloro bridged complex [Cu(μ-Cl)2(pyridine)2]n and its structure was solved by single X-ray crystallography. Antibacterial activities of all of the synthesized materials (1–12) were evaluated against Gram positive bacteria including Staphylococcus aureus and Bacillus subtilis and Gram negative bacteria including Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Proteus vulgaris. Fungi (Candida albicans, Aspergillus flavus) were also used to test antifungal activities with the compounds. Present study revealed that 8 shows best antibacterial activity among the present reported compounds. An excellent antifugal activity is shown by 12 emerging to be a better antibiotic than standard fluconazole. Besides fungicidal effect, 12 has promising larvicidal effect. The structure and activity relationship has been discussed.

Effect of fungal volatile organic compounds on a fungus and an insect that damage stored maize

The silo is an environment where a large number of biological interactions take place such as: insect-microorganism-grain interactions, which can generate great economic losses due to the deterioration in quality of the grain and the presence of mycotoxins. In recent years, particular interest has been focused on the search for environmentally friendly insecticides that will provide pest control in stored grains. The volatile organic compounds (VOCs), of a fungal origin, were evaluated for the control of maize grain pests: the insect Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), the fungus Fusarium verticillioides and its mycotoxin, fumonisin B1 (FB1). The most active fumigant compound tested was 1-octen-3-ol (LD50 = 27.7 μL/L air), followed by 3-octanol and 3-octanone (LD50 = 43.2 and 219.7 μL/L air, respectively). The fungal VOCs also showed repellent activity against S. zeamais, with antifugal activity against F. verticillioides growth being inhibited at concentrations greater than 0.53 mM, while its mycotoxin production capacity was inhibited depending on the compound concentration. At the repellent concentration, the fungal VOCs showed low phytotoxicity activities. The results presented in this paper demonstrate the potential of fungal VOCs as biopesticides, because they may control granivorous insects, fungal growth and FB1 production, which consequently is of economic importance and might improve food safety of stored grains.

English

The 80% ethanol extracts from 20 Chinese herbal medicines collected in Yunnan Province, China, were screened for antibacterial activity against Staphylococcus aureus (SA), methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli (EC) and Pseudomonas aeruginosa (PA), including antifugal activity against Candida albicans (CA) by the agar hole diffusion test. The extracts were prepared through macerating at room temperature and hot refluxing procedures. 19 of the 20 extracts showed effects with different potency and their inhibition zone diameters (IZD) ranged from 9 to 27 mm. The extracts from Psychotria henryi Levl and Marsdenia tinctoria R. Br. (maceration and reflux extraction) were the most active against both SA and MRSA, with mean IZDs = 19.7 to 22.0 mm. The anti-SA and MRSA active extracts were further determined for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by serial dilution with a standard broth microdilution method. 12 extracts showed effects on both SA and MRSA strains with MICs/MBCs ranges among 32 to ≥ 1024 / 64 to ≥ 1024 mg/L, respectively. P. henryi, M. tinctoria and Sapium baccatum Roxb also showed inhibition against EC, PA and CA strains, and displayed a broad spectrum of antimicrobial activities. Key words: Chinese herbal, methicillin-resistant Staphylococcus aureus (MRSA), minimum inhibitory concentrations (MIC).

Chemical composition, antibacterial and antifungal properties of Tunisian Nigella sativa fixed oil

We investigated the chemical composition (by gas chromatography) and anti-microbial activity of the Tunisian Nigella sativa fixed oil against different standard Gram-negative and Gram-positive strains and Candida isolates by disc diffusion method, and determined the minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and minimal fungicidal concentration (MFC) values. Twenty three fatty acids were identified in N. sativa fixed oil. Palmitic acid was the major saturated fatty acids (SFA) accounted for 12.2% of the total fatty acid (TFA). For monounsaturated fatty acids (MUFA), oleic acid was the major one with 21.67% of TFA. Linoleic acid has the most important percentage (58.73% of TFA) and was the major polyunsaturated fatty acids (PUFA). For the antibacterial activity, the best inhibition was seen against Staphylococcus aureus ATCC 25923 (16.66 mm) andSalmonella typhimurium ATCC 14028 (15.33 mm). The best antifugal activity was found against Candida parapsilosis ATCC 22019 (13.33 mm) and Candida glabata ATCC 90030 (12 mm). This fixed oil can be used as an antibacterial and antifungal agent each time the MIC values have a good effect on the antibacterial and antifungal activities of the TunisianN. sativa fixed oil. Our results demonstrate important antibacterial and antifungal activities of the Tunisian N. sativa fixed oil; these effects further validate the traditional use of N. sativain the folk medicine against bacterial and fungal infection. Key words: Nigella sativa, fixed oil, gas chromatography (GC), antibacterial activity and antifungal activity.

Computational evaluation and experimental in vitro antibacterial, antifungal and antiviral activity of bis-Schiff bases of isatin and its derivatives

A computational model has been developed for the rational design of bioactive pharmacophore sites as an antibacterial, antifungal and antiviral candidates based on available X-ray structures of bis-Schiff bases (Blagus et al., Maced J Chem Chem Eng 29:117–138, 2010; Nabei et al., Polyhedron 28:1734–1739, 2009; Zhang et al., Inorg Chem Commun 14:1636–1639, 2011; Zhong et al., Eur J Med Chem 41:1090–1092, 2006; Zhou et al., Inorg Chim Acta 359:1442–1448, 2006). A dozen of bis-Schiff bases 3–14 of isatin, benzylisatin and 5-fluoroisatin 1a–c were designed using this model. The compounds were screened for antibacterial, antifugal and antiviral activity against a panel of DNA and RNA viruses. The most potent of these compounds 8 and 11 was tested in viral cultures for their ability to present a potential (Oδ−–Nδ−) antiviral pharmacophore site. Compounds 8 and 11 were the most cytotoxic in HEL cells. All these synthesized bis-Schiff bases were also tested for their antibacterial and antifungal activities. They did not display activity against S. cerevisiae (ATCC 28383) or C. albicans (CIP 1180-79); may be because they did not have an antibacterial pharmacophore site (Xδ−–Yδ+). The best inhibitors tested in vitro against HIV-1 are genetically predisposed to be inhibited by similar pharmacophore sites. The results from all the aspects of this bioinformatic approaches are discussed as par with our experience with screening candidates.

Antifungal activity of four honeys of different types from Algeria against pathogenic yeast: Candida albicans and Rhodotorula sp.

ObjectiveTo evaluate the antifungal activity of four honeys of different types from Algeria against pathogenic yeast i.e. Candida albicans (C. albicans) and Rhodotorula sp. MethodsFour Algeria honeys of different botanical origin were analyzed to test antifungal effect against C. albicans, and Rhodotorula sp. Different concentrations (undiluted, 10%, 30%, 50% and 70% w/v) of honey were studied in vitro for their antifugal activity using C. albicans and Rhodotorula sp. as fungal strains. ResultsThe range of the diameter of zone of inhibition of various concentrations of tested honeys was (7–23 mm) for Rhodotorula sp., while C. albicans showed clearly resistance towards all concentrations used. The MICs of tested honey concentrations against C. albicans and Rhodotorula sp. were (70.09–93.48)% and (4.90–99.70)% v/v, respectively. ConclusionsThis study demonstrates that, in vitro, these natural products have clearly an antifungal activity against Rhodotorula sp. and C. albicans.

Seaweed polysaccharides and derived oligosaccharides stimulate defense responses and protection against pathogens in plants.

Plants interact with the environment by sensing “non-self” molecules called elicitors derived from pathogens or other sources. These molecules bind to specific receptors located in the plasma membrane and trigger defense responses leading to protection against pathogens. In particular, it has been shown that cell wall and storage polysaccharides from green, brown and red seaweeds (marine macroalgae) corresponding to ulvans, alginates, fucans, laminarin and carrageenans can trigger defense responses in plants enhancing protection against pathogens. In addition, oligosaccharides obtained by depolymerization of seaweed polysaccharides also induce protection against viral, fungal and bacterial infections in plants. In particular, most seaweed polysaccharides and derived oligosaccharides trigger an initial oxidative burst at local level and the activation of salicylic (SA), jasmonic acid (JA) and/or ethylene signaling pathways at systemic level. The activation of these signaling pathways leads to an increased expression of genes encoding: (i) Pathogenesis-Related (PR) proteins with antifungal and antibacterial activities; (ii) defense enzymes such as pheylalanine ammonia lyase (PAL) and lipoxygenase (LOX) which determine accumulation of phenylpropanoid compounds (PPCs) and oxylipins with antiviral, antifugal and antibacterial activities and iii) enzymes involved in synthesis of terpenes, terpenoids and/or alkaloids having antimicrobial activities. Thus, seaweed polysaccharides and their derived oligosaccharides induced the accumulation of proteins and compounds with antimicrobial activities that determine, at least in part, the enhanced protection against pathogens in plants.

Antifungal effect of Calotropis procera stem bark on Epidermophyton flocosum and Trichophyton gypseum

The antifugal activities of aqueous extract of Calotropics procera was determined against Epidermophyton flocosum and Tricophyton gypseum using agar diffusion techniques. The crude extract of C. procera showed activity on E. flocosum and T. gypseum at 4.0 mg/ml. The result of minimum inhibitory concentration (MIC) was 0.5 and 0.9 mg/ml and that of minimum fungicidal concentration (MFC) was 2.0 and 4.0 mg/ml, respectively. The result of the Ames test indicated that the crude extract is not mutagenic. Phytochemical screening of the crude extract revealed the presence of saponin, tannins, sequiterpene and alkaloids. The results of the study suggest that C. procera stem could be a potential source of chemotherapeutic drugs for the treatment of tinea associated with E. flocosum and T. gypseum.