Red Kale (Brassica oleracea L. ssp. acephala L. var. sabellica) Induces Apoptosis in Human Colorectal Cancer Cells In Vitro.

This article presents the results of studies investigating the effect of red kale (Brassica oleracea L. ssp. acephala L. var. sabellica) extract on cancer cells (HT-29). The cytotoxicity of the red kale extract was assessed using MTT and LDH assays, while qRT-PCR was employed to analyze the expression of genes associated with the p53 signaling pathway to elucidate the effect of the extract on cancer cells. Furthermore, HPLC-ESI-QTOF-MS/MS was applied to identify bioactive compounds present in red kale. The obtained results indicated that red kale extract reduced the viability and suppressed the proliferation of HT-29 cells (the IC50 value of 60.8 µg/mL). Additionally, mRNA expression analysis revealed significant upregulation of several genes, i.e., casp9, mapk10, mapk11, fas, kat2 b, and ubd, suggesting the induction of cell apoptosis through the caspase-dependent pathway. Interestingly, the study revealed a decrease in the expression of genes including cdk2 and cdk4 encoding cell cycle-related proteins, which may lead to cell cycle arrest. Furthermore, the study identified certain bioactive compounds, such as sinigrin, spirostanol, hesperetin and usambarensine, which could potentially contribute to the apoptotic effect of red kale extracts. However, further investigations are necessary to elucidate the specific role of these individual compounds in the anti-cancer process.

Biological Activity of an Epilobium angustifolium L. (Fireweed) Infusion after In Vitro Digestion.

The biological activity of an in vitro digested infusion of Epilobium angustifolium (fireweed) was examined in a model system of intestinal epithelial and colon cancer tissues. The content of selected phenolic compounds in the digested aqueous extract of fireweed was determined using HPLC-ESI-QTOF-MS/MS. Biological activity was examined using the human colon adenocarcinoma cell lines HT-29 and CaCo-2 and the human colon epithelial cell line CCD 841 CoTr. Cytotoxicity was assessed by an MTT assay, a Neutral Red uptake assay, May-Grünwald-Giemsa staining, and a label-free Electric Cell-Substrate Impedance Sensing cytotoxicity assay. The effect of the infusion on the growth of selected intestinal bacteria was also examined. The extract inhibited the growth of intestinal cancer cells HT-29. This effect can be attributed to the activity of quercetin and kaempferol, which were the most abundant phenolic compounds found in the extract after in vitro digestion. The cytotoxicity of the fireweed infusion was dose-dependent. The highest decrease in proliferation (by almost 80%) compared to the control was observed in HT-29 line treated with the extract at a concentration of 250 µg/mL. The fireweed infusion did not affect the growth of beneficial intestinal bacteria, but it did significantly inhibit E. coli. The cytotoxic effect of the fireweed extract indicates that it does not lose its biological activity after in vitro digestion. It can be concluded that the fireweed infusion has the potential to be used as a supporting agent in colon cancer therapy.

Potentilla alba Extracts Affect the Viability and Proliferation of Non-Cancerous and Cancerous Colon Human Epithelial Cells.

The aim of this study was to determine the anti-tumor activity of extracts isolated from Potentilla alba L. on human colon cancer cells of the HT-29 line and on non-cancer colon epithelial cells of the CCD 841 CoTr line. The research methods we used to determine the cytotoxic and proliferative properties were 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red (NR) assays, the ability to produce nitric oxide, the Griess method, and the biochemical properties like 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods indicating reduction activity of tested samples. Finally, the effects of the extracts on the morphology and cell counts were assessed by May-Grünwald-Giemsa staining. After a comprehensive analysis of all the experiments, the extracts were found to demonstrate cytotoxic properties, they stimulated the division of non-cancer cells, and they were able to scavenge free radicals. In the NR method, the cell viability dropped to approximately 80% compared to the control. In the MTT assay, tumor cell proliferation decreased to 9.5% compared to the control. Therefore, we concluded that this plant has medical potential.

Study on Biological Activity of Bread Enriched with Natural Polyphenols in Terms of Growth Inhibition of Tumor Intestine Cells.

A complex plant polyphenolic preparation (PP) was produced from chokeberry, raspberry, wild strawberry, peach, bilberry, apricot, cranberry, and parsley, using ultrafiltration and C18 preparative chromatography. Thirty main compounds were identified in PP (LC-MS), with the highest contribution of cyanidin 3-O-glucoside, p-coumaroyl glucoside, chlorogenic acid, neochlorogenic acid, and isoquercetin. PP was used (at 0.16% m/m) for the production of a sourdough bread (based on rye flour, water, and salt), followed by in vitro digestion. Fluid obtained after PP-enriched bread digestion (EBD fluid) was tested in terms of cytotoxicity, growth inhibition, antioxidant activity, and morphological changes in cancerous intestinal epithelial cells (HT-29) and normal (CCD 841 CoTr). Results show that EBD fluid concentration over 125 µg/mL significantly decreased activity of succinate dehydrogenase in HT-29 cells and reduced their viability of 25%. At this concentration of EBD fluid, modification in cellular morphology was also observed. DPPH analysis revealed that the highest antioxidant activity was observed at concentration of 75 µg/mL, both PP and EBD fluid. Our results show that an introduction of PP into relatively low-polyphenolic, baking products should be carefully considered because polyphenols still retain its biological activity. Antioxidant activity of polyphenols is one of the mechanisms that explains the observed effect of inhibiting the growth of colon cancer cells.

Application of response surface methodology to enhancement of biomass production by Lactobacillus rhamnosus E/N

Response surface methodology (RSM) was employed to study the effects of various medium components on biomass production by Lactobacillus rhamnosus E/N. This strain is commonly used in the pharmaceutical and food industries due to its beneficial effect on the human gut and general health. The best medium composition derived from RSM regression was (in g/l) glucose 15.44, sodium pyruvate 3.92, meat extract 8.0, potassium phosphate 1.88, sodium acetate 4.7, and ammonium citrate 1.88. With this medium composition biomass production was 23 g/l of dry cell weight after 18 h of cultivation in bioreactor conditions, whereas on MRS the yield of biomass was 21 g/l of dry cell weight. The cost of 1 g of biomass obtained on MRS broth was calculated at the level of 0.44 € whereas on the new optimal medium it was 25 percent lower. It may be concluded then, that the new medium, being cheaper than the control MRS allows large scale commercial cultivation of the L. rhamnosus strain. This study is of relevance to food industry because the possibility to obtain high yield of bacterial biomass is necessary step in manufacturing of probiotic food.