|
|
Cell culture-based model for the evaluation of adhesive properties of probiotic bacteria
Theodorou, Vasiliki ; Havlík, Jaroslav (advisor) ; Tauchen, Jan (referee)
Probiotic microorganisms, defined as living microorganisms which when administered in adequate amounts confer a health benefit to the host, and their adhesion and colonization of intestinal epithelium, are critical factors in maintaining probiotic efficacy. Polyphenols are a large and heterogeneous group of phytochemicals in plant-based foods, such as tea, coffee, wine, cocoa, cereal grains, soy, fruits and berries. In the last decade, there has been much interest in the health benefits of dietary plant polyphenols that arise from their potential ability to promote adhesion of probiotic bacteria to the human intestinal epithelium.
The purpose of this study was to investigate the effect of four polyphenols: isoquercetrin, phloretin, procyanidin B2 and rutin on the adhesion ability of two potentially probiotic strains (Lactobacillus casei, Lactobacillus gasseri) to in vitro human intestinal epithelial model consisting of Caco-2 and mucus-secreting HT29-MTX co-culture.
The adhesion of Lactobacillus casei after treating the co-culture cell lines with isoquercetrin, phloretin, and rutin was increased by 49.76, 72.97, 63.66 % respectively, whereas procyanidin B2 inhibited the adhesion 20.25% compared with the control sample. The adhesion of Lactobacillus gasseri after treatment of the co-culture with isoquercetrin, phloretin, procyanidin B2 and rutin was increased by 35.45, 31.28, 45.69, 25.01 % respectively compared with the control sample.
|
|
|
Assessment of in vitro antioxidant properties of medicinal and edible plant extracts
Tauchen, Jan ; Kokoška, Ladislav (advisor) ; Jaromír , Jaromír (referee)
Identification and characterization of plant-based products with antioxidant and anti-proliferative effects has received much interest over the past few years as possible therapeutic mean for treatment of diseases likely to be associated to oxidative stress (such as atherosclerosis, diabetes, and cancer). This study provides characterization of in vitro antioxidant and/or anti-proliferative potential and phytochemical profile of (i) 39 wine samples of underutilized Georgian grapevine cultivars, (ii) extracts of 22 samples of medicinal plants from Ethiopia and (iii) 23 samples of edible and medicinal plants from Peruvian Amazon. For this purpose, 2,2-diphenyl-1-picrylhydrazyl radical assay (DPPH), oxygen radical absorbance capacity (ORAC) assay, total phenolic content (TPC), and cell viability assay based on metabolization of tetrazolium bromide (MTT) to formazan, together with methods based on high performance liquid chromatography (HPLC-ultra violet/visible spectrometry and HPLC-tandem mass spectrometry) were used. Georgian red wines (particularly Saperavi cultivars) exhibited higher antioxidant capacity (average DPPH and ORAC values at 5.1 and = 10.6 g TE/L wine, respectively) in comparison to Central and West European cultivars [Pinot Noir (DPPH = 3.1 and ORAC = 9.4 g TE/L wine), Cabernet Sauvignon (DPPH = 3.0 and ORAC = 7.3 g TE/L wine) and Cabernet Moravia (DPPH = 2.0 and ORAC = 8.5 g TE/L wine)]. Georgian wines contained significantly greater concentrations of quercetin (between 14.44 and 1.07 ug/mL), kaempferol (between 1.68 and 0.03 ug/mL) and syringic acid (between 12.59 and 4.72 ug/mL), whereas possessed lower quantities of resveratrol (between 5.11 and 0.32 ug/mL) in comparison to Central and West European wines. Amongst edible and medicinal plants from Ethiopia and Peruvian Amazon, only Dodonaea angustifolia (IC50 for DPPH = 22.2 ug/mL, ORAC = 767.6 ug TE/mg extract; IC50 for Hep-G2 = 120.0 ug/mL), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract; IC50 for Hep-G2 = 50.5 ug/mL), Inga edulis (DPPH and ORAC = 337.0 and 795.7 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 36.3 and 57.9 ug/mL) and Oenocarpus bataua (DPPH and ORAC = 903.8 and 1024.4 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 102.6 and 38.8 ug/mL) have demonstrated combinatory antioxidant/anti-proliferative efficacy. Selective anti-proliferative activity was observed for Verbascum sinaiticum (IC50 for Hep-G2 = 80.6 ug/mL) and Annona montana (IC50 for Hep-G2 and HT-29 = 2.7 and 9.0 ug/mL, respectively). Above-mentioned plant material showed only weak or non-toxic effects towards normal cell line. Despite the fact that extracts of Jasminum abyssinicum (IC50 for DPPH = 26.3 ug/mL, ORAC = 1023.7 ug TE/mg extract), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract), Mauritia flexuosa (DPPH and ORAC = 1062.9 and 645.9 ug TE/mg extract), Myrciaria dubia (DPPH and ORAC = 641.9 and 642.6 ug TE/mg extract) and Theobroma grandiflorum (DPPH and ORAC = 714.8 and 821.9 ug TE/mg extract) have exhibited considerable antioxidant effect, these species were found to possess moderate to low anti-proliferative potential or have shown to be toxic to normal cells line. In all cases it was detected that phenolic compounds content correlated strongly with antioxidant activity, however weakly with anti-proliferative effect. Results suggest above-mentioned species as prospective materials for further development of novel plant-based agents effective against oxidative stress related diseases. However, it is necessary to perform further research which would be focused on detailed characterization of their chemical composition, pharmacological effects and toxicological safety, in order to verify their possible practical use.
|
|
|
In vitro antioxidative effect of medicinal plants from Ghana
Addai, Benjamin Berkoh ; Kokoška, Ladislav (advisor) ; Tauchen, Jan (referee)
The in vitro antioxidative activity of crude extracts derived from sixteen Ghanaian plant species (Allophylus spicatus, Cnestis ferruginea, Ficus thonningii, Indigofera hirsuta, Indigofera pulchra, Launaea taraxacifolia, Leea guineense, Mikaniopsis tedliei, Millettia thonningii, Philenoptera cyanescens, Salacia senegalensis, Senna occidentalis, Stachytarpheta indica, Tiliacora warneckei, Triumfetta rhomboidea, Vernonia colorata) were tested in frame of this study using 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity assay. The extract from the bark of Indigofera hirsuta has been found as the most active sample (IC50 = 12.84 more or less 0.82 microgram per millitres), because its activity is very close to the positive control Trolox and ascorbic acid. We expect that this finding may be used by pharmaceutical industry for development of new herbal-based nutraceuticals and pharmaceutical preparations.
|
guest ::
