scholarly journals A novel nano-sulphur and essential oil-based room freshener

Author(s):  
Ashwini S. Kaware ◽  
Pramod U Ingle ◽  
Aniket K. Gade ◽  
Mahendra Rai

Introduction: Alternaria spp. and Candida spp. are the main fungal pathogen of indoor environment like house, office, classroom, etc. These may cause various diseases and infections like systemic infections, or chronic asthma in immunocompromised individuals through secretion of various toxic substances. Chemical-based commercially available room fresheners used to control the fungal load of indoor environment are not beneficial to human health. Objective: was to provide viable alternative in the form of nanoparticle-based approach for the management of air-borne fungi. Methodology: The present study primarily focuses on the isolation, microscopic and biochemical identification of indoor fungi; Azadirachta indica-mediated sulphur nanoparticles (SNPs) synthesis, their detection and characterization; and in vitro assessment of SNPs against isolated fungi present in indoor environment. Result: The isolated fungi were identified as Alternaria spp and Candida spp. The SNPs showed absorbance maxima at 291 nm. NTA analysis showed average size of 188.4 nm, and zeta potential of -4.94 mV which represented synthesis of stable SNPs. XRD pattern confirmed the face centered cubic, crystalline nature of SNPs. FTIR spectrum depicted the presence of polyhydroxyl, nitrile, keto, aromatic and carboxylic compounds which stabilized the SNPs. The antifungal assays demonstrated the significant activity of the formulated SNPs and eucalyptus oil infused air freshener. Conclusion: It can be concluded that A. indica-mediated SNPs can be applied in the formulation and manufacture of an ecofriendly air freshener for the management of indoor fungal pathogens like Alternaria spp. and Candida spp.

2012 ◽  
Vol 2 (5) ◽  
pp. 217-226
Author(s):  
E. O. Omwenga ◽  
P. O. Okemo ◽  
P. K. Mbugua

The antimicrobial effect of some selected Samburu medicinal plants was evaluated on bacterial strains like Staphylococcus aureus ‐ ATCC 20591, Bacillus subtillis ‐ Local isolate, Salmonella typhi‐ATCC 2202, Escherichia coli‐STD. 25922 and Pseudomonas aeroginosa ‐ ATCC 25852 and fungal strains like Candida albicans ATCC EK138, Aspergillus niger ATCC 16404, Aspergillusflavus‐Local isolate, Fusarium lateritium‐Local isolate, and Penicillium spp.‐ local isolate. Methanol was used as solvent for the extraction from the selected medicinal plants used by the Samburu community. The in vitro antimicrobial activity was performed by agar disc diffusion and micro‐dilution technique. The most susceptible Gram‐positive bacterium was S. aureus, while the most susceptible Gram‐negative bacterium was P. aeroginosa. The extracts of Gomphocarpus fruticosus (L) W.T. Aiton showed less activity against the bacterial strains investigated. The most active antibacterial plants were Euphorbia scarlatica S. Carter, and Euclea divinoram Hiern. Incidentally most of the extracts were inactive against the fungal strains with only a few proving to be slightly active against the C. albicans i.e. Loranthus acaciae Zucc., Kedrostis pseudogijef (Gilg) C. Jeffrey, Euclea divinoram Hiern. and Croton macrostachyus (A. Rich). Benths. The significant antimicrobial activity of active extracts was compared with the standard antimicrobials, cefrodoxima, amoxicillin and fluconazole. The MICs of the most active plants ranged from 18.75mg/ml to 37.50mg/ml. The MBCs ranged between 18.75mg/ml to75mg/ml. These results were significant at P< 0.01. The findings show that most of the medicinal plants used by the Samburu community have some significant activity on the bacterial but not fungal pathogens known to cause diarrhoea.


2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Fengchang Huang ◽  
Yaxin Long ◽  
Qingqing Liang ◽  
Boregowda Purushotham ◽  
Mallappa Kumara Swamy ◽  
...  

With the advancement of nanobiotechnology, eco-friendly approaches of plant-mediated silver nanomaterial (AgNP) biosynthesis have become more attractive for biomedical applications. The present study is a report of biosynthesizing AgNPs using Chlorophytum borivilianum L. (Safed musli) callus extract as a novel source of reducing agent. AgNO3 solution challenged with the methanolic callus extract displayed a change in color from yellow to brown owing to the bioreduction reaction. Further, AgNPs were characterized by using UV–visible spectrophotometry, X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), and Fourier Transform Infrared Spectroscopy (FTIR). UV–vis spectrum revealed the surface plasmon resonance property of AgNPs at around 450 nm. XRD pattern with typical peaks indicated the face-centered cubic nature of silver. AFM analysis confirmed the existence of spherical-shaped and well-dispersed AgNPs having an average size of 52.0 nm. Further, FTIR analysis confirmed the involvement of different phytoconstituents of the callus extract role in the process of bioreduction to form nanoparticles. The AgNPs were more efficient in inhibiting the tested pathogenic microbes, namely, Pseudomonas aeruginosa, Bacillus subtilis, Methicillin-resistant Escherichia coli, Staphylococcus aureus, and Candida albicans compared to callus extract. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay confirmed the cytotoxic property of AgNPs against human colon adenocarcinoma cell line (HT-29) in a dose-dependent manner. At higher concentrations of 500 μg/mL AgNPs, the cell viability was observed to be only 7% after 24 hours with IC50 value of 254 μg/mL. Therefore, these AgNPs clearly endorse the manifold potential to be used in various biomedical applications in the near future.


1991 ◽  
Vol 6 (4) ◽  
pp. 755-759 ◽  
Author(s):  
R. Allem ◽  
G. L'Espérance ◽  
Z. Altounian ◽  
J.O. Ström-Olsen

The microstructure of two metastable crystalline phases, which are formed during the first step of the crystallization process in Ni–Zr metallic glasses, was investigated by transmission electron microscopy. For the composition Ni33Zr67, crystallites with average size of 150 nm having the face-centered cubic E93 structure are formed. For the Ni42Zr58 composition, 100 nm size crystallites with a simple cubic unit cell, space group Pa3 are formed. The microstructure of the crystallites in the early stage of crystallization of the two phases is similar to globular morphology and internal striations.


2020 ◽  
Vol 21 (4) ◽  
pp. 177
Author(s):  
Siti Suhartati ◽  
Iwan Syahjoko Saputra ◽  
Dwinna Rahmi ◽  
Yoki Yulizar ◽  
Sudirman Sudirman

BIOREDUCTION AND CHARACTERIZATION OF SILVER NANOPARTICLES FROM OIL PALM EMPTY FRUIT BUNCH (OPEFB). The synthesis of silver nanoparticles was successfully carried out by extracting oil palm empty fruit bunch. The precursor used was silver nitrate (AgNO3) with a concentration of 9x10-4 M and 5 wt% of the oil palm empty fruit bunch extract. OPEFB acted as a capping agent in the synthesis of silver nanoparticles. The bioreduction method Ag+ to Ag0 produced a silver nanoparticle colloid in brown color. The results of the UV-Vis spectrophotometer showed the silver nanoparticles colloids spectrum at a wavelength of 420 nm with an absorbance value of 0.5. FTIR shows the reduction and shift of absorption peak in the hydroxyl functional group (-OH) at wavenumbers of 3323 cm-1 and the presence of absorption peaks at 560 cm-1. While, XRD pattern showed the specific crystallinity peaks of silver nanoparticles at 2θ: 33.24°; 39.98°; 61.23°; dan 79.13° respectively with the face-centered cubic crystal structure (FCC) and crystallite size of 15 nm. PSA analysis showed two specific peaks with an average size distribution silver nanoparticles of 43.5 nm and a PDI value of 0.4. Analysis of TEM shows the average particle size of 20 nm with a spherical particle shape.


Pharmaceutics ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 918
Author(s):  
Irene Heredero-Bermejo ◽  
Natalia Gómez-Casanova ◽  
Sara Quintana ◽  
Juan Soliveri ◽  
Francisco Javier de la Mata ◽  
...  

Candida spp. are one of the most common fungal pathogens. Biofilms formed by Candidaalbicans offer resistance mechanisms against most antifungal agents. Therefore, development of new molecules effective against these microorganisms, alone or in combination with antifungal drugs, is extremely necessary. In the present work, we carried out a screening process of different cationic carbosilane dendritic molecules against C. albicans. In vitro activity against biofilm formation and biofilms was tested in both Colección Española de Cultivos Tipo (CECT) 1002 and clinical C. albicans strains. Cytotoxicity was studied in human cell lines, and biofilm alterations were observed by scanning electron microscopy (SEM). Antifungal activity of the carbosilane dendritic molecules was assessed by monitoring cell viability using both established and novel cell viability assays. One out of 14 dendritic molecules tested, named BDSQ024, showed the highest activity with a minimum biofilm inhibitory concentration (MBIC) for biofilm formation and a minimum biofilm damaging concentration (MBDC) for existing biofilm of 16–32 and 16 mg/L, respectively. Synergy with amphotericin (AmB) and caspofungin (CSF) at non-cytotoxic concentrations was found. Therefore, dendritic compounds are exciting new antifungals effective at preventing Candida biofilm formation and represent a potential novel therapeutic agent for treatment of C. albicans infection in combination with existing clinical antifungals.


Author(s):  
Mrridula Dangi Narwal ◽  
Meenakshi Balhara ◽  
Renu Chaudhary ◽  
Chhillar Ak

Scientific and clinical reports globally demonstrated that the opportunistic mycotic infections are at major risk to the human fitness. In past few decades, development of resistance in microbes to existing antifungals, has emphasized on the search of new antimycotic drugs. As a matter of fact "echinocandins" are new categories of broad-spectrum antifungal enlighten a hope in this direction. Echinocandins are bulky lipopeptides that inhibits the production of β-[1,3]-glucan "a major constituent of fungal cell wall" which ultimately leads to the death of fungal pathogens. In vitro as well as in vivo published reports have demonstrated that the echinocandins exhibit fungicidal activity against most Candida spp while fungistatic against Aspergillus spp and exclusively found to be more effective when tested in combination with polyenes/azoles. Present article is an expert views on the recent and historical literature available on the antifungal therapies with accessing their impact on the human health. Emphasis is given on the utility of the echinocandins as potential antifungal agent by discussing recent examples of clinical and laboratory studies including the use of improved proteomics approaches to know a bit more about the interaction of human host and fungal pathogens.


1995 ◽  
Vol 39 (4) ◽  
pp. 868-871 ◽  
Author(s):  
H M Wardle ◽  
D Law ◽  
C B Moore ◽  
C Mason ◽  
D W Denning

We compared the in vitro activity of a new triazole, D0870, with those of fluconazole, itraconazole, and ketoconazole against 41 clinical isolates of fluconazole-resistant Candida belonging to nine different species. The 50% inhibitory concentrations (IC50s) were determined by a microdilution method with morpholinopropanesulfonic acid (MOPS)-buffered RPMI medium and an inoculum of approximately 10(4) yeasts per ml. After incubation for 48 h at 37 degrees C the optical density at 550 nm was measured. The IC50 was the lowest drug concentration which reduced the optical density at 550 nm by > or = 50% compared with that for a drug-free control. D0870 had significant activity against many of the isolates. Its activity was comparable to that of ketoconazole, slightly superior to that of itraconazole, and markedly superior to that of fluconazole against Candida albicans. Against Candida glabrata, Candida krusei, and Candida inconspicua, it had activity similar to those of itraconazole and ketoconazole but had activity superior to that of fluconazole. D0870 IC50s for some isolates were increased. This may be due to cross-resistance mechanisms because the IC50s of both itraconazole and ketoconazole for these isolates were often high. When IC50s and IC80s were compared there was a marked organism and drug variation. With C. glabrata much higher endpoints for itraconazole were observed when an IC80 endpoint was used. For C. albicans there was also a significant shift upward in endpoints for itraconazole and ketoconazole. Values were changed little when IC50 and IC80 endpoints of D0870 were compared. For 35 of 41 isolates tested the D0870 IC50 was less than the 2.5-mg/liter breakpoint threshold proposed previously. Therefore, D0870 may be a useful agent for the therapy of infections caused by fluconazole-resistant Candida spp.


2001 ◽  
Vol 45 (11) ◽  
pp. 3132-3139 ◽  
Author(s):  
Esperanza Herreros ◽  
Maria Jesus Almela ◽  
Sonia Lozano ◽  
Federico Gomez De Las Heras ◽  
Domingo Gargallo-Viola

ABSTRACT GW 471552, GW 471558, GW 479821, GW 515716, GW 570009, and GW 587270 are members of a new family of sordarin derivatives called azasordarins. The in vitro activities of these compounds were evaluated against clinical isolates of yeasts, including Candida albicans, Candida non-albicans, and Cryptococcus neoformans strains. Activities againstPneumocystis carinii, Aspergillus spp., less common molds, and dermatophytes were also investigated. Azasordarin derivatives displayed significant activities against the most clinically important Candida species, with the exception of C. krusei. Against C. albicans, including fluconazole-resistant strains, MICs at which 90% of the isolates tested are inhibited (MIC90s) were 0.002 μg/ml with GW 479821, 0.015 μg/ml with GW 515716 and GW 587270, and 0.06 μg/ml with GW 471552, GW 471558, and GW 570009. The MIC90s of GW 471552, GW 471558, GW 479821, GW 515716, GW 570009, and GW 587270 were 0.12, 0.12, 0.03, 0.06, 0.12, and 0.06 μg/ml, respectively, against C. tropicalis and 4, 0.25, 0.06, 0.25, 0.5, and 0.5 μg/ml, respectively, against C. glabrata. In addition, some azasordarin derivatives (GW 479821, GW 515716, GW 570009, and GW 58720) were active against C. parapsilosis, with MIC90s of 2, 4, 4, and 1 μg/ml, respectively. The compounds were extremely potent againstP. carinii, showing 50% inhibitory concentrations of ≤0.001 μg/ml. However Cryptococcus neoformans was resistant to all compounds tested (MIC > 16 μg/ml). These azasordarin derivatives also showed significant activity against emerging fungal pathogens, which affect immunocompromised patients, such as Rhizopus arrhizus, Blastoschizomyces capitatus, and Geotrichum clavatum. Against these organisms, the MICs of GW 587270 ranged from 0.12 to 1 μg/ml, those of GW 479821 and GW 515716 ranged from 0.12 to 2 μg/ml, and those of GW 570009 ranged from 0.12 to 4 μg/ml. AgainstFusarium oxysporum, Scedosporium apiospermum, Absidia corymbifera,Cunninghamella bertholletiae, and dermatophytes, GW 587270 was the most active compound, with MICs ranging from 4 to 16 μg/ml. Against Aspergillus spp., the MICs of the compounds tested were higher than 16 μg/ml. The in vitro selectivity of azasordarins was investigated by cytotoxicity studies performed with five cell lines and primary hepatocytes. Concentrations of compound required to achieve 50% inhibition of the parameter considered (Tox50s) of GW 570009, GW 587270, GW 479281, and GW 515716 in the cell lines ranged from 60 to 96, 49 to 62, 24 to 36, and 16 to 38 μg/ml, respectively. The cytotoxicity values of GW 471552 and GW 471558 were >100 μg/ml for all cell lines tested. Tox50s on hepatocytes were in the following order: GW 471558 > GW 471552 > GW 570009 > GW 587270 > GW 515716 > GW 479821, with values ranging from higher than 100 μg/ml to 23 μg/ml. The cytotoxicity results obtained with fully metabolizing rat hepatocytes were in total agreement with those obtained with cell lines. In summary, the in vitro activities against important pathogenic fungi and the selectivity demonstrated in mammalian cell lines justify additional studies to determine the clinical usefulness of azasordarins.


2001 ◽  
Vol 45 (10) ◽  
pp. 2862-2864 ◽  
Author(s):  
M. A. Pfaller ◽  
S. A. Messer ◽  
R. J. Hollis ◽  
R. N. Jones

ABSTRACT Posaconazole is a new investigational triazole with broad-spectrum antifungal activity. The in vitro activities of posaconazole were compared with those of itraconazole and fluconazole against 3,685 isolates of Candida spp. (3,312 isolates) and C. neoformans (373 isolates) obtained from over 70 different medical centers worldwide. The MICs of the antifungal drugs were determined by broth microdilution tests performed according to the National Committee for Clinical Laboratory Standards method using RPMI 1640 as the test medium. Posaconazole was very active against all Candida spp. (MIC at which 90% of the isolates were inhibited [MIC90], 0.5 μg/ml; 97% of MICs were ≤1 μg/ml) and C. neoformans(MIC90, 0.5 μg/ml; 100% of MICs were ≤1 μg/ml).Candida albicans was the most susceptible species ofCandida (MIC90, 0.06 μg/ml), andCandida glabrata was the least susceptible (MIC90, 4 μg/ml). Posaconazole was more active than itraconazole and fluconazole against all Candida spp. and C. neoformans. These results provide further evidence for the spectrum and potency of posaconazole against a large and geographically diverse collection of clinically important fungal pathogens.


2016 ◽  
Vol 8 (2) ◽  
pp. 1100-1109 ◽  
Author(s):  
Anita Puyam

Trichoderma spp are free living filamentous fungi. They are cosmopolitan and versatile in nature. They have the potential to produce several enzymes that can degrade the cell wall materials. Also, they release a number of fungi toxic substances that can inhibit the growth of the fungal pathogens. Many mechanisms have been described on how Trichoderma exert beneficial effects on plants as a bio-control agent. But due to its versatile nature, its potential cannot be explored to its full extent. And it is a developing science in the field of bio-control with its new discoveries adding to the usefulness of the fungi as a bio-control agent. Its development as a bio-control agent passes through many phases and each phase adding novel ideas that will help in the development of an efficient bio-agent which in turn will help in the crop improvement and disease management. The studies on their various aspects responsible for bio-control will open a flood gate to the development of Trichoderma as an efficient and reliable bio-agent and provide a better scope for implementation in crop and disease management. The in vitro antagonistic activity of Trichoderma viride against phytopathogens (Sclerotium rolfsii, Fusarium oxysporum f.s.p. ciceri, Fusarium oxysporum f.s.p. udum) was studied and it was found to be potentially effective against F. oxysporum f.s.p. ciceri followed by F. oxysporum f.s.p. udum and Sclerotium rolfsii.


Sign in / Sign up

Export Citation Format

Share Document