scholarly journals In Vitro Effects ofPlantago MajorExtract, Aucubin, and Baicalein onCandida albicansBiofilm Formation, Metabolic Activity, and Cell Surface Hydrophobicity

2015 ◽  
Vol 26 (6) ◽  
pp. 508-515 ◽  
Author(s):  
Karina Pezo Shirley ◽  
L. Jack Windsor ◽  
George J. Eckert ◽  
Richard L. Gregory
Author(s):  
Kamni Rajput ◽  
Ramesh Chandra Dubey

In this paper, an investigation on lactic acid bacterial isolates from ethnic goat raw milk samples were examined for their probiotic potential and safety parameters. For this purpose, isolated bacterial cultures were screened based on certain parameters viz., sugar fermentation, tolerance to temperature, salt, low pH, bile salts, and phenol resistance. After that, these bacterial cultures were more estimated in vitro for auto-aggregation, cell surface hydrophobicity, response to simulated stomach duodenum channel, antibiotic resistance, and antimicrobial activity. Besides, probiotic traits show the absence of gelatinase and hemolytic activity supports its safety. The isolate G24 showed good viability at different pH, bile concentration, phenol resistance and response to simulated stomach duodenum passage but it did not show gelatinase and hemolytic activities. Isolate G24 was susceptible to amikacin, carbenicillin, kanamycin, ciprofloxacin, co-trimazine, nitrofurantoin, streptomycin, and tetracycline. Isolate G24 also exhibited antimicrobial action against five common pathogenic bacteria, such as Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogens, and Salmonella typhimurium. It displayed the maximum auto-aggregation, cell surface hydrophobicity to different hydrocarbons. Following molecular characterization the isolate G24 was identified as Enterococcus hirae with 16S rRNA gene sequencing and phylogeny. E. hirae G24 bears the excellent properties of probiotics.


1999 ◽  
Vol 62 (3) ◽  
pp. 252-256 ◽  
Author(s):  
C. GUSILS ◽  
A. PÉREZ CHAIA ◽  
S. GONZÁLEZ ◽  
G. OLIVER

Lactobacillus strains were tested for their in vitro probiotic properties. Cell surface hydrophobicity was found to be very high for Lactobacillus fermentum subsp. cellobiosus and Salmonella Gallinarum; high values could indicate a greater ability to adhere to epithelial cells. Studies on Lactobacillus animalis indicated relative cell surface hydrophobicities smaller than those of L. fermentum subsp. cellobiosus and L. fermentum. L. animalis and Enterococcus faecalis were able to coaggregate with L. fermentum subsp. cellobiosus and L. fermentum, respectively, but not with Salmonella Gallinarum. After mixed-culture studies for determining suitable growth behavior, the pair of strains L. animalis plus L. fermentum subsp. cellobiosus was selected for an attempted challenge against Salmonella Gallinarum. Double and triple mixed-culture studies indicated that selected lactobacillus strains were able to retain their beneficial characteristics in the presence of Salmonella Gallinarum such as presence of lectins, production of antimicrobial compounds, and ability to grow and compete. The selected microorganisms can be considered as potential ingredients for a chicken probiotic feed formulation intended to control salmonellosis and also improve poultry sanitation.


Fermentation ◽  
2020 ◽  
Vol 6 (3) ◽  
pp. 91
Author(s):  
Gabriela Krausova ◽  
Antonin Kana ◽  
Ivana Hyrslova ◽  
Iva Mrvikova ◽  
Miloslava Kavkova

Selenized lactic acid bacteria (LAB) represent potentially safe and effective sources of selenium (Se), essential for human health, as lactic acid fermentation improves Se bioavailability and reduces its toxicity. LAB are generally recognized as safe (GRAS) and widely used in fermented dairy products. To facilitate selenized LAB implementation as a functional food, we developed and characterized new Se-enriched strains based on the food industry commercial strains Streptococcus thermophilus CCDM 144 and Enterococcus faecium CCDM 922A as representatives of two LAB genera. We evaluated Se bioaccumulation capacity, Se biotransformation and growth ability in the presence of different sodium selenite concentrations (0–50 mg/L), and antioxidant properties (2, 2-diphenyl-1-picrylhydrazyl (DPPH) method) and cell surface hydrophobicity between Se-enriched and parental strains in vitro. Sodium selenite addition did not negatively influence growth of either strain; thus, 50 mg/L was chosen as the optimal concentration based on strain accumulation capacity. Selenization improved the antioxidant properties of both strains and significantly increased their cell surface hydrophobicity (p < 0.05). To our knowledge, this represents the first report of Se-enriched strain hydrophobicity as well as the first on Se speciation in families Enterococcaceae and Streptococcaceae. Moreover, both tested strains demonstrated good potential for Se-enrichment, providing a foundation for further in vitro and in vivo studies to confirm the suitability of these Se-enriched strains for industrial applications.


2019 ◽  
Author(s):  
Yuria Chihara ◽  
Yutaka Tanaka ◽  
Minoru Izumi ◽  
Daisuke Hagiwara ◽  
Akira Watanabe ◽  
...  

ABSTRACTThe pathogenic fungus Aspergillus fumigatus contains galactomannans localized on the surface layer of its cell walls, which are involved in various biological processes. Galactomannans comprise α-(1→2)-/α-(1→6)-mannan and β-(1→5)-/β-(1→6)-galactofuranosyl chains. We previously revealed that GfsA is a β-galactofuranoside β-(1→5)-galactofuranosyltransferase involved in the biosynthesis of β-(1→5)-galactofuranosyl chains. Here, we clarified the entire biosynthesis of β-(1→5)-galactofuranosyl chains in A. fumigatgus. Two paralogs exist within A. fumigatus: GfsB and GfsC. We show that GfsB and GfsC, in addition to GfsA, are β-galactofuranoside β-(1→5)-galactofuranosyltransferases by biochemical and genetic analyses. GfsA, GfsB, and GfsC can synthesize β-(1→5)-galactofuranosyl oligomers up to lengths of 7, 3, and 5 galactofuranoses within an established in vitro highly efficient assay of galactofuranosyltransferase activity. Structural analyses of galactomannans extracted from the strains ΔgfsB, ΔgfsC, ΔgfsAC, and ΔgfsABC revealed that GfsA and GfsC synthesized all β-(1→5)-galactofuranosyl residues of fungal-type and O-mannose-type galactomannans, and GfsB exhibited limited function in A. fumigatus. The loss of β-(1→5)-galactofuranosyl residues decreased the hyphal growth rate and conidia formation ability as well as increased the abnormal hyphal branching structure and cell surface hydrophobicity, but this loss is dispensable for sensitivity to antifungal agents and virulence toward immune-compromised mice.IMPORTANCEβ-(1→5)-galactofuranosyl residues are widely distributed in the subphylum Pezisomycotina of the phylum Ascomycota. Pezizomycotina includes many plant and animal pathogens. Although the structure of β-(1→5)-galactofuranosyl residues of galactomannans in filamentous fungi was discovered long ago, it remains unclear which enzyme is responsible for biosynthesis of this glycan. Fungal cell wall formation processes are complicated, and information concerning glycosyltransferases is essential for their understanding. In this study, we show that GfsA and GfsC are responsible for the biosynthesis of all β-(1→5)-galactofuranosyl residues of fungal-type and O-mannose-type galactomannans. The data presented here indicates that β-(1→5)-galactofuranosyl residues are involved in cell growth, conidiation, polarity, and cell surface hydrophobicity. Our new understanding of β-(1→5)-galactofuranosyl residue biosynthesis provides important novel insights into the formation of the complex cell wall structure and the virulence of the subphylum Pezisomycotina.


2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Mohd-Al-Faisal Nordin ◽  
Fathilah Abdul Razak ◽  
Wan Harun Himratul-Aznita

Bakuchiol is an active component ofPsoralea glandulosaandPsoralea corylifolia, used in traditional Chinese medicine. The study aimed at investigating the antifungal activity of bakuchiol on planktonic and biofilm forms of orally associatedCandidaspecies. The antifungal susceptibility testing was determined by the broth micro dilution technique. Growth kinetics and cell surface hydrophobicity (CSH) ofCandidawere measured to assess the inhibitory effect of bakuchiol onCandidaplanktonic cells. Biofilm biomass and cellular metabolic activity were quantitatively estimated by the crystal violet (CV) and the 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide (XTT) assays. AllCandidastrains have been shown to be susceptible to bakuchiol with the MIC ranges from 12.5 to 100 μg/mL. Significant decrease in specific growth rates and viable counts demonstrates the inhibitory effect of bakuchiol onCandidaplanktonic cells. A brief exposure to bakuchiol also reduced CSH ofCandida(P<0.05), indicating altered surface properties of yeast cells towards hydrophobic interfaces. Biofilm biomass and cell metabolic activity were mostly decreased, except forC. glabrata(P=0.29). The antifungal properties of bakuchiol onCandidaspecies in thisin vitrostudy may give insights into the application in therapeutic strategy againstCandidainfections.


2016 ◽  
Vol 54 (5) ◽  
pp. 632
Author(s):  
Nguyen Thi My Le ◽  
Nguyen Thi Huong

Lactobacillus strains are a major part of the probiotics, microflora of the intestine and of fermented foods. The aim of this study was to evaluate the potential probiotics of six Lactobacillus strains (L. fermentum 39-183; L. plantarum subsp.plantarum P-8; L. casei ATCC 334; L. rhamnosus ATCC 8530, L. brevis KB 290 and L. fermentum JMC 7776). Probiotic properties such as acid tolerance, bile resistance, bacteriocin-like activity, cell surface hydrophobicity and antibiotic resistance were assessed. In vitro results obtained showed that all Lactobacillus strains tested were able to meet the basic requirements for probiotic functions as they demonstrated probiotic characteristics such as tolerance to pH 2.0 and 2% bile salt. All Lactobacillus strains inhibited the growth of E. coli, Staphylococcus aureus and Salmonella Typhi. Among strains tested, L. plantarum subsp.plantarum P-8 showing inhibitory is very promising with inhibition zone ranging between 6.5 to 12.7 mm. The results for cell surface hydrophobicity and susceptibility against antibiotics also showed that L. fermentum JMC 7776 and L. plantarum subsp.plantarum P-8 had higher cell surface hydrophobicity than the rests.  All Lactobacillus tested were resistant to vancomycin and susceptible to streptomycin. The results obtained in this investigation will be used to select potentially probiotic strains for in vivo study


2008 ◽  
Vol 50 (4) ◽  
pp. 203-207 ◽  
Author(s):  
Ângela Maria Mendes Araújo ◽  
Ivi Cristina Menezes de Oliveira ◽  
Marcos Corrêa de Mattos ◽  
Leslie C. Benchetrit

The minimum inhibitory concentration and post-antibiotic effects of an antimicrobial agent are parameters to be taken into consideration when determining its dosage schedules. The in vitro post-antibiotic effects on cell surface hydrophobicity and bacterial adherence were examined in one strain of group B streptococci. Exposure of the microorganism for 2 h at 37 °C to 1 x MIC of penicillin induced a PAE of 1.1 h. The cell surface charge of the Streptococcus was altered significantly during the post-antibiotic phase as shown by its ability to bind to xylene: hydrophobicity was decreased. Bacterial adherence to human buccal epithelial cells was also reduced. The results of the present investigation indicate that studies designed to determine therapeutic regimens should evaluate the clinical significance of aspects of bacterial physiology during the post-antibiotic period.


Sign in / Sign up

Export Citation Format

Share Document