Authors:O. Temiz-Arpaci, B. Eylem Cifcioglu Goztepe, Fatma Kaynak-Onurdag, Selda Ozgen, Fatma Senol, and I. Erdogan Orhan
A series of 2-[4-(4-substitutedbenzamido/phenylacetamido/butanamido)phenyl]-5-ethylsulphonyl-benzoxazole derivatives were synthesized and biologically evaluated as possible antimicrobial agents and inhibitors of tyrosinase, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE). The results demonstrated that the synthesized compounds exhibited a broad spectrum of activity with minimum inhibitory concentration (MIC) values of 128-16 μg/ml against some Gram-positive, Gram-negative bacteria as well as Candida albicans and C. krusei. The compound 10 displayed higher activity in this series against methicilline resistant Staphylococcus aureus (MRSA) with a MIC value of 16 μg/ml than the compared control drugs ampicillin and ceftriaxone. Compound 14 showed moderate tyrosinase inhibition, however, none of the compounds showed effect as inhibitor of AChE and BChE.
Authors:J. Essien, A. Umoh, E. Akpan, S. Eduok, and A. Umoiyoho
Mycological research was conducted on the mycelial growth, keratinolytic proteinase activity and thermotolerance of dermatophytes associated with alopecia patients in Uyo, Nigeria. The results revealed that
sp. — AP
sp. — AP
and a yeast
isolated exhibited variable growth and keratinase activity at different temperatures.
sp. — AP
survived heat treatment at 90 °C but exhibited best mycelial growth at 30 °C (with 53.41 mg/50 ml biomass dry weight) and 40 °C (with 61.32 mg/50 ml biomass dry weight) respectively, after incubation for 2 weeks.
sp. — AP
could not survive heat treatment at 90 °C but grew better at 40 °C (with 38.52 mg/50 ml biomass dry weight) and 30 °C (with 48.32 mg/50 ml biomass dry weight) respectively, over the same incubation period, while
grew better at 30 °C with 38.7 mg/50 ml biomass dry weight after 2 weeks, but failed to survive at 70 °C. All the isolates except
survived at 80 °C and exhibited great potential to elaborate keratinolytic enzymes, with
demonstrating the best potential at 30 °C and 40 °C. Higher temperatures tended to reduce keratinolytic activities and there were significant (P <0.05) relationships between biomass weight and enzyme productivities of all the isolates except
. This indicates that in some dermatophytes keratinolytic proteinase activity is not a function of cell multiplicity. This plus the high thermostability of the enzymes are important attributes in the consideration of preventive and therapeutic methods against dermatophytes in the tropics.
Authors:Mihaela Badea, Rodica Olar, Dana Marinescu, Veronica Lazar, Carmen Chifiriuc, and Gina Vasile
This paper reports the investigation on the thermal stability of new complexes with mixed ligands of the type [Cd(NN)(C3H3O2)2(H2O)m]·nH2O [(1) NN: 1,10-phenantroline, m = 1, n = 0; (2) NN: 2,2′-bipyridine, m = 0, n = 1.5 and (C3H3O2): acrylate anion]. The IR data indicate a bidentate coordination mode for both heterocyclic amine and acrylate. The in vitro
qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity
against planktonic as well as biofilm embedded Gram-negative (Escherichiacoli, Klebsiella sp., Proteus sp., Salmonella sp., Shigella sp., Acinetobacterboumani, Pseudomonasaeruginosa), Gram-positive (Bacillussubtilis, Staphylococcusaureus) and fungal (Candida albicans) strains, reference and isolated ones from the hospital environment. The thermal behaviour steps were investigated
in synthetic air flow. The thermal transformations are complex processes according to TG and DTA curves including dehydration,
amine as well as acrylate thermolysis. The final products of decomposition are the most stable metal oxides.
Authors:B. Özcelik, I. Orhan, M. Kartal, and B. Konuklugil
The objective of this study was to examine antibacterial, antifungal and antiviral properties of selected
species (Lamiaceae) growing in Turkey. The petroleum ether and methanol extracts of the seven species, namely
P.H. Davis & Hub.-Mor.,
Sibth. & Sm.,
Velen. were tested against
Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus, Bacillus subtilis
for their antibacterial activity using ampicillin and oflaxocin as references. Antifungal activity of the same extracts was determined against
using microdilution method with ketocanazole as reference. Both DNA virus
type-1 (HSV-1) and RNA virus
(PI-3) were employed for antiviral assessment of the
extracts using Madin-Darby Bovine Kidney and Vero cell lines in which acyclovir for HSV-1 and oseltamivir for PI-3 were employed as reference drugs. Although both the petroleum ether and methanol extracts seemed to exert similar antibacterial activity, the methanolic extracts were observed to be more active against
. On the other hand, methanolic extract of
possessed notable antiviral activity against both type of viruses.
Authors:Lise Laurençon, Thi Kieu Tien Do, Francis Hadji-Minaglou, Sylvain Antoniotti, and Xavier Fernandez
A previous study on Solidago virgaurea extracts showed an inhibiting activity of Candida albicans yeast—hyphal transition due to a mixture of triterpene saponins, leading to applications in the field of oral care products. Such applications require the development of an efficient, fast, and simple quantification method of S. virgaurea total saponins. Two methods were developed: the first was based on high-performance liquid chromatography (HPLC) separation with gradient elution and evaporative light scattering detection (ELSD); the second was based on high-performance thin-layer chromatography (HPTLC) separation with in-situ hydrolysis followed by densitometric measurements at 366 nm. Both calibration curves showed good linear regressions (R2 > 0.99) within the range of the concentrations tested. The limit of detection (LOD) and the limit of quantitation (LOQ) were 2–4 μg and 10–16 μg, respectively. The intra- and inter-day variations were studied and found to remain below 5.6% in terms of relative standard deviation (RSD). The recoveries were 97.02–101.91% with RSD of 0.3–1.96% for spiked sample. Both validated methods were successfully applied to the analysis of total saponins in different S. virgaurea samples. In particular, a harvesting study could be supported by these methods to identify the most relevant vegetal parts to extract, and the locations and vintage to collect, to obtain the desired active saponins. HPLC is the recommended method for precise analyses, but HPTLC is the most efficient for the fast analysis of multiple samples.
Authors:Kedar Rout, Bandita Dash, and Rajesh Singh
An important bioactive molecule, ursolic acid was isolated from the leaves of Diospyros melanoxylon and characterized with help of physical and spectroscopic data viz. m. p, IR, 1H, and 13C NMR. A high-performance thin-layer chromatography method has also been developed and validated for its quantification in D. melanoxylon leaves. The high-performance thin-layer chromatography analysis was performed on high performance thin-layer chromatography plates using chloroform-methanol (9.5:0.5, v/v) as mobile phase. The compound was quantified at 540 nm after derivatzation with sulphuric acid reagent. The sensitivity of the method with respect to limit of detection and limit of quantification were found to be 20 and 40 ng per spot. The response was obtained as a linear function of peak area and concentration in the range of 50 to 450 ng per spot with correlation coefficient of r2 = 0.9998. The method showed excellent accuracy greater than 97.54% with acceptable precession and was successfully validated according to International Conference of Harmonization protocols. Antimicrobial screenings of ursolic acid revealed potent activity against two Gram-positive bacteria viz. Staphylococcus aureus and Enterococcus faecalis and three fungal starins viz. Aspergillus niger, Candida tropicalis, and Candida albicans.
This study examines the antibacterial properties of sodium hypochlorite (NaOCl), chlorhexidine gluconate (CHX), Listerine®, and high purity chlorine dioxide (Solumium, ClO2) on selected common oral pathogen microorganisms and on dental biofilm in vitro. Antimicrobial activity of oral antiseptics was compared to the gold standard phenol. We investigated Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis, Veillonella alcalescens, Eikenella corrodens, Actinobacillus actinomycetemcomitans and Candida albicans as some important representatives of the oral pathogens. Furthermore, we collected dental plaque from the upper first molars of healthy young students. Massive biofilm was formed in vitro and its reduction was measured after treating it with mouthrinses: CHX, Listerine® or hyper pure ClO2. Their biofilm disrupting effect was measured after dissolving the crystal violet stain from biofilm by photometer. The results have showed that hyper pure ClO2 solution is more effective than other currently used disinfectants in case of aerobic bacteria and Candida yeast. In case of anaerobes its efficiency is similar to CHX solution. The biofilm dissolving effect of hyper pure ClO2 is significantly stronger compared to CHX and Listerine® after 5 min treatment. In conclusion, hyper pure ClO2 has a potent disinfectant efficacy on oral pathogenic microorganisms and a powerful biofilm dissolving effect compared to the current antiseptics, therefore high purity ClO2 may be a new promising preventive and therapeutic adjuvant in home oral care and in dental or oral surgery practice.
Authors:S. Sirilun, C. Chaiyasut, D. Kantachote, and P. Luxananil
The aims of this study were to isolate LAB from Thai plant-derived foods and beverages and to examine in vitro probiotic properties including b-glucosidase enzyme activity. Lactobacillus plantarum SC 359 selected from Thai pickled soybean was significantly (P<0.05) the best to perform β-glucosidase enzyme activity (0.396 U ml−1 at 18 h of incubation) out of the 227 tested strains. The strain survived in 0.30% (w/v) bile salt and had high tolerance to acidic pH with survival rates at a 2 h period of 72.24%, 85.52%, 92.64%, and 93.38% at pH 2.0, 3.0, 4.0, and 5.0, respectively. The SC 359 strain showed proteolytic and lipolytic activities. Moreover, the selected strain displayed strong antagonistic activities against Bacillus cereus ATCC 11778, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Salmonella Typhi, Shigella sonnei and Candida albicans ATCC 90028. The strain was susceptible to ampicillin, chloramphenicol, erythromycin, gentamicin, kanamycin, rifampicin, streptomycin, tetracycline, and vancomycin. In addition, the selected strain significantly inhibited the adherence to Caco-2 cells of E. coli, S. Typhi and Sh. sonnei (P<0.05) by 33.50 to 73.37%. The strain could obstruct the adherences of pathogens by elimination, competition, and displacement with pathogen adherences 33.62–53.92%, 26.63–59.23%, and 49.41–66.50%, respectively. Based on the results, the selected strain could be applied as functional starter for Thai fermented plant-derived foods and beverages.
Authors:Erika Dósa, Ilona Dóczi, L. Mojzes, Etelka G. Molnár, J. Varga, and Erzsébet Nagy
The fungal revolution taking place in otorhinology inspired us to study the frequency of occurrence of fungi in the nasal mucus of chronic rhinosinusitis (CRS) patients (with or without polyposis) in order to evaluate the incidence of eosinophilic fungal sinusitis in CRS patients. Ninety-six samples were examined from patients with CRS. In 74 cases mucus was collected non-invasively, and in 22 cases during operation. The Gram-stained direct smears of all samples were also evaluated. Bacteria and fungi colonizing in the mucus were detected by culturing method. The control group consisted of 50 healthy volunteers. Typical aerobic pathogenic bacteria could be isolated from 34 patients. Fifty-seven aerobic bacteria were isolated, i.e. 1.6 bacteria/positive patient with a maximum of 3 different bacteria/sample. The most frequently isolated bacteria were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, and Haemophilus influenzae. Yeasts and moulds could be detected from 79 patients (83%): Candida albicans, Candida spp., Aspergillus spp., Cladosporium spp, and Penicillium spp. were isolated most frequently. Altogether 237 yeasts and moulds were isolated, i.e. 3.0 different fungi/positive patient, with a maximum of 5 different fungi/sample. In the control group aerobic pathogens were not isolated, only apathogenic species. Fungi were isolated from 22 healthy patients (44%). These data indicate that fungi are frequently involved in the aetiology of CRS. IgE-mediated hypersensitivity to fungal allergens could not be proven in our patients.