Assessment of probiotic properties of lactic acid bacteria isolated from an artisanal Colombian cheese.

Lactic Acid Bacteria play an important role in the milk fermentation processes of traditional cheeses and have become an important target for the development of novel cheese cultures because of their ability to confer health benefits. This study aimed to evaluate the probiotic potential of 12 Lactic Acid Bacteria (LAB) strains previously isolated and molecularly identified from an artisanal Colombian Double-Cream Cheese. Probiotic properties, including safety (hemolysis and sensibility to antibiotics), pH and bile salt tolerance, auto-aggregation, cell surface hydrophobicity, antibacterial activity, and exopolysaccharide production, were examined. None of the strains were hemolytic, and Pediococcus (16, 18) and Lactobacillus (28, 29) were found to be sensitive to all antibiotics. Moreover, all the strains tolerated pH (3.0, 6.5 and 8.0) and bile salt conditions (0.3, 0.6 and 1.0 % w/v). Pediococcus pentosaceus (16), Leuconostoc citreum (17), Pediococcus acidilactici (18), Enterococcus faecium (21,22), Enterococcus faecalis (24) and Limosilactobacillus fermentum (29) exhibited medium autoaggregation and affinity to chloroform. Six of the strains exhibited a ropy exopolysaccharide phenotype. Antibacterial activity against foodborne pathogens, Salmonella Typhimurium ATCC 14028, Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923, was found to be strain dependent, with the strains 16, 18, 21, 26, 28 and 29 presenting a higher inhibition (>4 mm) against all of them. According to Principal Component Analysis, P. pentosaceus (16), Leu. mesenteroides (26), L. casei (28), L. fermentum (29), and E. faecium (21) showed strong probiotic properties. Our findings suggest that five strains out of the 12 sampled strains are potential probiotics that could be used in the processing of traditional dairy products on an industrial scale to improve their quality.

Actividad citotóxica y genotóxica de ácidos grasos omega en células de cáncer de próstata PC-3 / Cytotoxic and Genotoxic Activity of Omega Fatty Acids in Prostate Cancer Cells PC-3

RESUMEN Introducción: en el mundo, el cáncer de próstata es la principal causa de muerte en hombres. Algunas evidencias sugieren que los ácidos grasos omega-3 reducen la viabilidad de las células tumorales mientras que los ácidos omega-6 promueven su proliferación; al respecto, otros estudios han mostrado resultados controvertidos. Objetivo: evaluar los efectos citotóxicos, genotóxicos y anticlonogénicos de ácidos omega-3: α-linolénico (ALA), eicosapentaenoico (EPA) y docosahexaenoico (DHA), omega-6: linoleico (LA), araquidónico (AA) y omega-9: oleico (OA) en células de cáncer de próstata (PC-3). Metodología: se evaluó el efecto sobre la viabilidad celular relativa mediante las pruebas de MTT y Azul de Tripano, el efecto genotóxico mediante intercambios de cromátidas hermanas (ICHs) y ensayo cometa, y el efecto anticlonogénico in vitro, en diferentes concentraciones (25, 50, 100 y 150 µM) de seis ácidos grasos omega en células de cáncer de próstata (PC-3). Resultados: la viabilidad relativa por MTT mostró valores ≤ IC50 con las concentraciones mayores (100 y 150 µM) para los ácidos grasos omega-3 EPA y DHA y omega-6 AA (150 µM), mientras que la viabilidad relativa, evaluada con Azul de Tripano, con estos mismos ácidos, redujeron la viabilidad a 0 %. DHA y EPA mostraron efecto genotóxico y la disminución de la clonogenicidad celular (p < 0,01). Por otro lado, LA y AA disminuyeron la viabilidad relativa observada con Azul de Tripano, sugiriendo diferentes mecanismos de acción de los ácidos grasos en la membrana celular. Conclusión: los resultados mostraron que los ácidos grasos omega-3, EPA, DHA, y omega-6, AA, disminuyen la formación de colonias, reducen la viabilidad celular y aumentan el efecto genotóxico respecto al control no tratado, en el modelo in vitro de células tumorales de próstata PC-3.

SUMMARY Introduction: Prostate cancer is the main cause of cancer related deaths in men worldwide. Previous studies have suggested that omega-3 fatty acids reduce cell viability in tumour cells, whereas omega-6 fatty acids increase clonogenicity. Nevertheless, other reports have shown controversial results. Objective: Evaluate cytotoxicity, genotoxicity and clonogenicity in a prostate cancer derived human cell line (PC-3), treated with fatty acids omega-3: α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); omega-6: linoleic acid (LA) and arachidonic acid (AA); omega-9: oleic acid (OA). Methods: The tests included (a) cytotoxicity assays by MTT and Trypan Blue; (b) genotoxicity evaluation by the sister-chromatid exchanges technique (SCE) and the DNA-comet assay; and (c) in vitro clonogenic assay of six fatty acids in prostate cancer cell (PC-3) at different concentrations (25 µM, 50 µM, 100 µM and 150 µM). Results: The cell viability by MTT data showed ≤ IC50 values for the omega-3 EPA and DHA and omega-6 AA fatty acids at the two major concentrations (100 µM and 150 µM). Moreover, the same fatty acids viability values dropped to 0 % with Trypan Blue test. EPA and DHA showed genotoxic effect and a clonogenic cell decrease (p<0,01). The latter test also revealed a viability diminishment for LA and AA, suggesting different mechanisms of action of fatty acids on cell membrane. Conclusion: The in vitro evaluation revealed that EPA, DHA and AA reduce the clonogenicity and cell viability of prostate tumour cells and cause genotoxicity in prostate tumour derived PC-3 cells.

Effect of isoespintanol isolated from Oxandra cf. xylopioides against DNA damage of human lymphocytes.

Synthetic antioxidants are used in the food and pharmaceutical industry, however, there is concern about their safety; this has prompted the search for new antioxidants that are effective, safe and act at low concentrations. The objective of this study is to evaluate the oxygen radical scavenging capacity and clastogenic effect of the Isoespintanol /2-isopropyl-3,6-dimethyl-5-methylphenol) in DNA of human lymphocyte compared with the BHA (Butylated hydroxyanisole). The oxygen radical scavenging ability was evaluated by methods ORACFL and ORACPGR, genotoxicity was determined by comet assay and data analysis was performed using ANOVA and Duncan test. The results show that the oxygen radical scavenging capacity of the BHA is higher than Isoespintanol, however according to the reactivity concept proposed by Lopez-Alarcon and Lissi, the Isoespintanol it is more reactive than BHA. Furthermore, according to some studies, BHA presented adverse effects on the health of consumers. Comet assay results revealed that at concentrations between 3 and 1620 µM the Isoespintanol don't show clastogenic effects on DNA. In conclusion, the antioxidant capacity for the BHA is higher than Isoespintanol, but considering reactivity concepts proposed by López-Alarcon and Lissi, the Isoespintanol is faster to neutralize radicals that the BHA, furthermore, according to the National Institute of Health "BHA" is a human carcinogen.

Synthesis and cytotoxic activity of tri-acyl ester derivatives of uridine in breast cancer cells / Síntesis y actividad citotóxica de derivados triesterificados de la uridina en células de cáncer de mama

Aims: Synthesize tri-acyl ester derivatives of uridine, and evaluate its cytotoxicity against breast cancer cells line. Methods: The tri-esterified uridine derivatives were obtained through Steglich esterification reaction by fatty and aromatic acids, and with acetic anhydride. An acetonide derivative from uridine was prepared with acid catalysis. Compounds were characterized by NMR spectroscopy (1H NMR and 13C NMR), and mass spectrometry. Derivatives were assessed in chinese hamster ovary (CHO-K1) and human breast cancer (MCF-7) cell lines. Results: Five tri-acyl ester derivatives of uridine were obtained one acetic acid, three fatty acids (myristic acid, stearic acid and oleic acid) with an aromatic acid. The uridine per-acetylated and uridine acetonide were obtained in high yields, however, the tri-acyl ester derivatives of uridine with fatty and aromatic acids were obtained in moderate and low yields, respectively. The acetonide and compounds 2 and 3 exhibited a cell viability inhibition significant on both cell lines to the higher concentration. Conclusions: Esterification method with coupling agents allowed obtained tri-acyl ester uridine derivatives with aliphatic and aromatic acids. However, significant cytotoxic activity (p<0.05) for uridine and its derivatives was not observed

Objetivos: Sintetizar derivados triesterificados de la uridina y evaluar su citotóxicidad sobre una línea celular de cáncer de mama. Métodos: Se prepararon derivados triesterificados de la uridina mediante la esterificación de Steglich para los ácidos grasos y aromáticos, y con anhídrido acético. Además se preparó el derivado acetonido mediante catálisis ácida. Los compuestos se caracterizaron por espectroscopia de RMN (RMN 1H y RMN 13C), y espectrometría de masas. Los derivados se evaluaron sobre líneas celulares de tumor de ovario de hámster chino (CHO) y de cáncer de mamá (MCF-7). Resultados: Se obtuvieron cinco derivados triesterificados de la uridina, uno con ácido acético, tres con ácidos grasos (ácido mirístico, ácido esteárico y ácido oleico) y uno con ácido aromático. Los derivados de uridina per-acetilada y acetonido se obtuvieron con rendimientos altos, sin embargo los derivados con ácidos grasos y aromático, se obtuvieron con rendimientos moderados y bajo, respectivamente. El acetonido y los compuestos 2 y 3, exhibieron inhibición significativa de la viabilidad celular sobre ambas líneas a la concentración más alta evaluada. Conclusiones: El método de esterificación con agentes de acoplamiento utilizado, permitió obtener derivados triesterificados de la uridina con ácidos grasos y aromáticos. No se observó actividad citotóxica significativa (p<0,05) para la uridina y sus derivados

Síntesis y actividad citotóxica de conjugados de la uridina con triterpenos en células de cáncer de mama / Synthesis and cytotoxic activity of conjugates of the uridine with triterpenes on breast cancer cells

Objetivos: Sintetizar conjugados del acetónido de la uridina con triterpenos (colesterol y 3β-5α,8α- endoperoxido-colest-6-en-3-ol) y ácido succínico como puente. Métodos: Se preparó el acetónido de la uridina en acetona mediante catálisis ácida. Se prepararon los succinatos de los esteroles con anhídrido succínico y catalizador nucleofílico 4-N,N-dimetilamino-piridina (DMAP). Los conjugados 1 y 2 se sintetizaron mediante la esterificación de Steglich, con agente de acoplamiento N,N’-diciclohexilcarbodiimida (DCC)y DMAP. Los compuestos se caracterizaron por espectroscopia de RMN (1H RMN y 13C RMN) y espectrometría de masas. Los derivados se evaluaron sobre líneas celulares de ovario de hámster chino (CHO-K1) y de cáncer de mamá (MCF-7). Resultados: Se obtuvieron derivados conjugados del acetónido de la uridina con dos triterpenos con rendimientos superiores al 80%. Los conjugados de uridina con triterpenos no presentaron inhibición significativa de la viabilidad celular sobre las líneas celulares MCF-7 y CHO-K1, tampoco se evidenció una relación dosis-respuesta para los compuestos evaluados. Conclusiones: El método de esterificación con agentes de acoplamiento permitió obtener conjugados de la uridina con triterpenos empleando el ácido succínico como puente. Sin embargo los derivados de uridina obtenidos no presentaron actividad citotóxica significativa (p < 0,05) sobre las líneas celulares evaluadas

Aims: Synthesize of uridine acetonide conjugates with triterpenoids (cholesterol and 3β-5α,8α-endoperoxide- cholest-6-en-3-ol) and succinic acid as linking. Methods: The acetonide derivative of uridine was prepared with acid catalysis in acetone. Sterols succinates were prepared with succinic anhydride and nucleophilic catalyst 4-N,N-dimethylamino-pyridine (DMAP). The conjugates were synthesized by Steglich method with N,N’-dicyclohexylcarbodiimide (DCC) Coupling agent and DMAP. The compounds were characterized by NMR spectroscopy (1H NMR, 13C NMR), and mass spectrometry. The derivatives were assessed in Chinese Hamster Ovary (CHO) and breast cancer (MCF-7) cell lines. Results: The conjugates of uridine acetonide with two triterpenes were obtained with yields higher than 80%. The conjugates prepared don’t showed significant inhibition of cell viability on MCF-7 and CHO cell lines, furthermore these substances did not show a relationship dose-response. Conclusions: The esterification method with coupling agents allowed obtained uridine conjugates with triterpenoids. However the uridine derivatives don’t showed significant cytotoxic activity (p < 0,05) against cell lines evaluated

Efecto de extractos de la esponja calcarea Leucetta aff. floridana sobre el ciclo de líneas celulares leucemoides / Effect of extracts from the calcareous sponge Leucetta aff. floridana on the cell cycle of leukemoid cell lines

La esponja Leucetta aff. floridana produce compuestos con actividad antiproliferativa diferencial en células tumorales de pulmón y mama, la cual no ha sido explorada en otras líneas tumorales y se desconoce si su potencial antiproliferativo está relacionado con la progresión de células a través del ciclo celular. Objetivo: evaluar el potencial antiproliferativo, anticlonogénico y el efecto sobre el ciclo celular de los extractos hexánico y metanólico de la esponja Leucetta aff. floridana del Caribe colombiano en las líneas celulares leucemoides Jurkat y K562. Métodos: la viabilidad y proliferación celular se determinaron mediante el ensayo de azul de tripano a 0, 24, 48, 72 y 96 h. La eficiencia de clonación y el efecto sobre el ciclo celular se evaluaron a 10 y 100 µg/mL. Los datos se analizaron usando ANOVA multifactorial y la prueba Tukey. Resultados: el extracto hexánico presentó actividad antiproliferativa en ambas líneas celulares siendo Jurkat más sensible que K562, lo cual se corroboró con los ensayos de clonogenicidad. Este extracto también mostró un efecto de acumulación de células Sub-G1 dependiente de la dosis, el cual fue diferencial entre las dos líneas celulares. La duración del tratamiento con el extracto hexánico no fue significativa para las células K562 pero sí para la línea celular Jurkat. Además, el porcentaje de acumulación de las células Sub-G1 fue mayor para células K562 comparado con Jurkat. El extracto metanólico presentó un efecto antiproliferativo similar al hexánico, pero fue más potente con la menor concentración (10 µg/mL) en la clonogenicidad de K562. El efecto sobre el ciclo celular, también fue similar al hexánico, pero la duración del tratamiento no fue significativa en la acumulación de células en Sub-G1. Conclusiones: los resultados muestran el potencial diferencial de los extractos sobre el ciclo celular de las líneas leucemoides evaluadas...

Leucetta aff. floridana sponge produces compounds with differential antiproliferative activity on lung and breast cancer. Nevertheless, this activity in other tumour cell lines has not yet been tested and it remains unknown whether its antiproliferative potential is correlated with the cell progression through cell cycle or not. Objective: To evaluate the antiproliferative and anticlonogenic potential and the effect of methanolic and hexanic extracts of sponge L. aff. floridana from the Colombian Caribbean region on the cell cycle of Jurkat and K562 leukemoid cell lines. Methods: The viability and antiproliferative effect were determined using trypan blue assay at 0, 24, 48, 72 and 96 hours. Clongenicity and effect on cell cycle were assayed at 10 and 100 µg/mL Data obtained were analyzed using multifactorial ANOVA and Tukey's test. Results: The hexanic extract presented antiproliferative activity in both Jurkat and K652 cell lines; Jurkat being more sensitive than K652. These results were confirmed by clongenicity assays. The hexanic extract also showed its effect on the dose-dependent accumulation of Sub-G1 cells, although it was different in the two cell lines. The duration of the treatment with the hexanic extract was not significant for K562 cell line, but it was for Jurkat cells. Additionally, the percentage of cell accumulation in Sub-G1 was higher in K562 than in Jurkat cells. The methanolic extract showed antiproliferative effect similar to that of the hexanic extract, but more potent at the lowest concentration (10 µg/mL) in K652 cell line clonegenicity. The effect on cell cycle was also similar to that of the hexanic extract, but in this case the duration of treatment was not significant in the cell accumulation in Sub-G1. Conclusions: Altogether these results show the differential potential of the extracts on the cell cycle of the evaluated leukemoid cell lines...