53 research outputs found
Carotenoid composition and antioxidant activity of the raw and boiled fruit mesocarp of six populations of Bactris gasipaes
Total carotenoid content and composition of caro tenoids of six varieties of Bactris gasipaes were determined by spec trophotometry and HPLC, with photodiode array detector. Signifi cant differences in total carotenoid content (1.1 to 22.3 mg/100g) were detected among these varieties. Boiling the fruits for 30 min utes did not affect total carotenoid content, but did change the amount of some specific carotenoids, mainly by the production of Z-iso mers. Peach palm varieties had the same carotenoids, but in different proportions, presenting mainly, all E-β–carotene (26.2% to 47.9%), Z-γ-carotene (18.2% to 34.3%) and Z-lycopene (10.2% to 26.8%). When antioxidant activity was evaluated using DPPH, it was ob served that the variety with higher percentages of β-carotene (54.1%) presented the higher activity. This is one of the first reports in caro tenoid content and antioxidant activity in well typified varieties of Bactris gasipaes, whose results could have a positive impact in the consumption of certain peach palm varietiesUniversidad de Costa Rica/[422-A5-065]/UCR/Costa RicaConsejo Nacional para Investigaciones CientÃficas y Tecnológicas/[FV-028-03]/CONICIT/Costa RicaDeutsche Academische Austauschdienst/[]/DAAD/AlemaniaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Salud::Facultad de MicrobiologÃ
Porcentaje y cifra absoluta de linfocitos T en sangre periférica por el método de rosetas E: estudio de cuarenta adultos sanos
Se realizó la determinación del porcentaje y cifra absoluta de linfocitos T en sangre periférica a un grupo de 40 adultos sanos costarricenses, seleccionados de un grupo inicial de 58 voluntarios. Se utilizó un método de formación de rosetas E. Los valores obtenidos fueron (promedio ± 1 desviación estándar): 49 ± 11% células E+ y 1.521 ± 647 células E+/mm3. Al comparar estos valores con algunos otros descritos en la literatura se observa que, en general, las cifras relativas obtenidas son más bajas, mientras que las absolutas son muy similares. Se incluye una breve revisión teórica sobre diversos aspectos básicos y clÃnicos relacionados con la determinación de linfocitos T, mediante la formación de rosetas E.UCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP
Hormone replacement therapy reduces lipid oxidation directly at the arterial wall: A possible link to estrogens’ cardioprotective effect through atherosclerosis prevention
Background: The first step in atherosclerosis formation is the ingurgitation of an oxidized low‑density lipid (LDL)
molecule by a macrophage which then turns into a foam cell within the vascular wall and initiates a cascade
of inflammatory responses. Could it be that the potential cardioprotective effect observed in women receiving
hormone replacement therapy (HRT) is modulated by estrogen’s capacity to decrease LDL oxidation in the
vascular wall and thus decrease atherosclerotic foam cells?
Materials and Methods: Thirty‑four adult female Wistar rats were divided into three groups. All were double
oophorectomized. After recovery, Group 1 received Estradiol Valerate subcutaneous (SC) (2.5 mg/kg/week),
Group 2 Estradiol Valerate SC (2.5 mg/kg/week) + Progesterone SC (10 mg/kg/48 h), and Group 3 Placebo
SC. After 10 weeks, all rats were sacrificed and a vascular dissection performed. Malondialdehyde (MDA) was
measured directly on the vascular extract to determine lipid oxidative levels and HRTs’ effect. Renal and hepatic
tissue was also studied. Total antioxidant status (TAS) was measured to determine overall oxidative behavior.
Results: Vascular MDA levels for Group 1 = 80.80 (±16.8) μmol/ml/g, Group 2 = 107.69 (±24.9) μmol/ml/g, and
Group 3 = 140.96 (±32.4) μmol/ml/g. ANOVA (P < 0.05), with a post hoc Bonferroni corrective t‑test, showed that
both Group 1 and 2 have statistically significant lower levels of MDA than Group 3. Renal tissue showed less
oxidative damage in the HRT groups, while hepatic tissue showed an inverse behavior with less lipid oxidation
in the placebo group. TAS decreased with oophorectomy in all groups but decreased less in both groups that
received HRT compared to placebo (P < 0.05).
Conclusion: HRT significantly reduces lipid oxidation directly in the arterial wall.Universidad de Costa Rica/[]/UCR/Costa RicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de Medicin
Fractioning of Proanthocyanidins of Uncaria tomentosa. Composition and Structure-Bioactivity Relationship
In a previous study, the detailed low-molecular weight polyphenolic profile of the different plant parts (leaves, stem, bark and wood) of Uncaria tomentosa was reported, the leaves being the plant part with the highest phenolic content and presenting the most heterogenous proanthocyanidin composition. Further, cytotoxicity of leaves extracts in two cancer cell lines was also found to be higher than in the remaining parts of the plant. In the present study, fractioning of U. tomentosa leaves polyphenolic extracts was performed using Diaion® HP-20 resin and a detailed characterization and quantification of fractions (n = 5) was achieved using advanced analytical techniques such as Ultra-Performance Liquid Chromatography coupled with Electrospray Ionization and Triple Quadrupole (TQD) Tandem Mass Spectrometry (UPLC/TQ-ESI-MS) and 13C-NMR. Oxygen Radical Absorbance Capacity (ORAC) and cytotoxicity on gastric adenocarcinoma AGS and colon adenocarcinoma SW20 cell lines were also determined in the different fractions. Results showed selective distribution of 32 non-flavonoid and flavonoid phenolics among the different fractions. ORAC varied between 3.2 and 11.8 µmol TE/mg in the different fractions, whereas IC50 of cytotoxicity on gastric adenocarcinoma AGS and colon adenocarcinoma SW20 cell lines best values were between 71.4 and 75.6 µg/mL. Fractions rich in proanthocyanidins also showed the highest bioactivity. In fact, significant positive correlation was found between total proanthocyanidins (TP) quantified by UPLC-DAD and ORAC (R 2 = 0.970), whereas significant negative correlation was found between TP and cytotoxicity towards AGS (R 2 = 0.820) and SW620 (R 2 = 0.843) adenocarcinoma cell lines. Among proanthocyanidins, propelargonidin dimers were of particular interest, showing significant correlation with cytotoxic selectivity on both gastric AGS (R 2 = 0.848) and colon SW620 (R 2 = 0.883) adenocarcinoma cell lines. These results show further evidence of the bioactivity of U. tomentosa proanthocyanidin extracts and their potential health effects.Agencia Española de Cooperación Internacional para el Desarrollo/[A/023397/09]/AECID/EspañaAgencia Española de Cooperación Internacional para el Desarrollo/[A/030037/10]/AECID/EspañaCosta Rica-USA Foundation/[]/CRUSA/Costa RicaConsejo Superior de Investigaciones CientÃficas/[CR0024]/CSIC/EspañaUniversidad de Costa Rica/[]/UCR/Costa RicaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuÃmicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologÃ
Effect of an In Vitro Digestion on the Antioxidant Capacity of a Microfiltrated Blackberry Juice (Rubus adenotrichos)
The health benefits attributed to berries are largely dependent on their bioavailability. This study evaluated the antioxidant activity for different samples of blackberry juice submitted to an in vitro digestion. The HPLC analysis demonstrated that gastric conditions had only a slight impact on the phenolic composition, but the digestion simulating intestine conditions caused marked changes. The dialyzed fraction, which represents the serum available material, showed 33% and 35% less activity against nitrogen-derived radicals and a significant reduction of 46% in the inhibitory capacity against intracellular ROS. Other models used to evaluate the capacity to inhibit lipid peroxidation did not show significant differences in any of the digestion samples. Our results suggest that blackberry polyphenols could exert their antioxidant capacity after passage through the GIT. However, the dialyzed fraction suffers a partial depletion of its antioxidant ability, this could be attributed to the absence of ellagitannins.Universidad de Costa Rica/[801-B1-655]/UCR/Costa RicaUCR::VicerrectorÃa de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y TecnologÃa de Alimentos (CITA)UCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de Medicin
Polyphenolic Characterization, Antioxidant and Cytotoxic Activities of Mangifera indica cultivars from Costa Rica
Abstract: The phenolic profile of skin and flesh from Manifera indica main commercial cultivars (Keitt
and Tommy Atkins) in Costa Rica was studied using ultra performance liquid chromatography
coupled with high resolution mass spectrometry (UPLC-ESI-MS) on enriched phenolic extracts.
A total of 71 different compounds were identified, including 32 gallates and gallotannins (of different
polymerization degree, from galloyl hexose monomer up to decagalloyl hexoses and undecagalloyl
hexoses); seven hydroxybenzophenone (maclurin and iriflophenone) derivatives, six xanthonoids
(including isomangiferin and mangiferin derivatives); 11 phenolic acids (hydroxybenzoic and
hydroxycinnamic acid derivatives); and eight flavonoids (rhamnetin and quercetin derivatives).
The findings for T. Atkins skin constitute the first report of such a high number and diversity of
compounds. Also, it is the first time that the presence of gallotannin decamers and undecamers are
reported in the skin and flesh of Keitt cultivar and in T. Atkins skins. In addition, total phenolic content
(TPC) was measured with high values especially for fruits’ skins, with a TPC of 698.65 and 644.17 mg
gallic acid equivalents/g extract, respectively, for Keitt and T. Atkins cultivars. Antioxidant potential
using 2,2-diphenyl-1-picrylhidrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods
were evaluated, with T. Atkins skin showing the best values for both DPPH (IC50 = 9.97 µg/mL)
and ORAC (11.02 mmol TE/g extract). A significant negative correlation was found for samples
between TPC and DPPH antioxidant values (r = −0.960, p < 0.05), as well as a significant positive
correlation between TPC and ORAC (r = 0.910, p < 0.05) and between DPPH and ORAC antioxidant
methods (r = 0.989, p < 0.05). Also, cytotoxicity was evaluated in gastric adenocarcinoma (AGS),
hepatocarcinoma (HepG2), and colon adenocarcinoma (SW620), with T. Atkins skin showing the best
results (IC50 = 138–175 µg/mL). Finally, for AGS and SW 620 cell lines particularly, a high significant
negative correlation was found between cytotoxic activity and gallotannins (r = −0.977 and r = −0.940,
respectively) while for the HepG2 cell line, the highest significant negative correlation was found
with xanthonoids compounds (r = −0.921).Universidad de Costa Rica: Proyecto (115-B4-076).UCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuÃmic
Flavonoids and Ellagitannins Characterization, Antioxidant and Cytotoxic Activities of Phyllantus acuminatus Vahl.
The phenolic composition of leaves from Phyllanthus acuminatus L., a plant commonly used in Costa Rica as traditional medicine, was studied using UPLC-ESI-MS on an enriched phenolic extract. A total of 20 phenolic compounds were identified, comprising eight flavonoids (two flavanones—pinocembrin isomers and six derivatives from apigenin, chrysin, quercetin, and kaempferol); seven ellagitannins, two flavan-3-ols (prodelphinidin B dimer and (epi)gallocatechin); and three phenolic acids (ellagic acid, trimethylellagic acid, and ferulic acid). All of these compounds are reported for the first time in P. acuminatus, while previously reported in the genus Phyllanthus. Antioxidant evaluation was performed for P. acuminatus phenolic extract obtaining DPPH results with a remarkably low IC50 value of 0.15 µg/mL. Also, cytotoxicity on gastric AGS and colon SW20 adenocarcinoma cell lines was evaluated, and highly promising results were obtained, with IC50 values of 11.3 µg/mL and 10.5 µg/mL, respectively. Furthermore, selectivity index values obtained when comparing cytotoxicity on normal Vero cells was SI > 20 for both cancer cell lines, indicating a particularly high selectivity. Additionally, Justicidin B, a metabolite extensively studied for its antitumoral activity, was isolated from a non-polar extract of P. acuminatus, and comparatively evaluated for both bioactivities. The DPPH value obtained for Justicidin B was moderate (IC50 = 14.28 µg/mL), while cytotoxicity values for both AGS (IC50 = 19.5 µg/mL) and SW620 (IC50 = 24.8 µg/mL) cell lines, as well as selectivity when compared with normal Vero cells (SI = 5.4 and 4.2 respectively), was good, but lower than P. acuminatus extract. These preliminary results suggest that P. acuminatus enriched phenolic extract containing flavonoids, ellagitannins, flavan-3-ols, and phenolic acids, reported for the first time in this plant, could be of interest for further cancer cytotoxicity studies to elucidate structure–bioactivity relationships, and the molecular mechanisms and pathways.Consejo Nacional de Rectores/[Ref 115B0653]/CONARE/Costa RicaUniversidad de Costa Rica/[]/UCR/Costa RicaInstituto Tecnológico de Costa Rica/[]/TEC/Costa RicaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuÃmicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologÃ
Polyphenolic Characterization and Antioxidant Activity of Malus domestica and Prunus domestica Cultivars from Costa Rica
The phenolic composition of skin and flesh from Malus domestica apples (Anna cultivar) and Prunus domestica plums (satsuma cultivar) commercial cultivars in Costa Rica, was studied using Ultra Performance Liquid Chromatography coupled with High Resolution Mass Spectrometry (UPLC-DAD-ESI-MS) on enriched-phenolic extracts, with particular emphasis in proanthocyanidin and flavonoids characterization. A total of 52 compounds were identified, including 21 proanthocyanidins ([(+)-catechin and (−)-epicatechin]) flavan-3-ols monomers, five procyanidin B-type dimers and two procyanidin A-type dimers, five procyanidin B-type trimers and two procyanidin A-type trimers, as well as one procyanidin B-type tetramer, two procyanidin B-type pentamers, and two flavan-3-ol gallates); 15 flavonoids (kaempferol, quercetin and naringenin derivatives); nine phenolic acids (protochatechuic, caffeoylquinic, and hydroxycinnamic acid derivatives); five hydroxychalcones (phloretin and 3-hydroxyphloretin derivatives); and two isoprenoid glycosides (vomifoliol derivatives). These findings constitute the first report of such a high number and diversity of compounds in skins of one single plum cultivar and of the presence of proanthocyanidin pentamers in apple skins. Also, it is the first time that such a large number of glycosylated flavonoids and proanthocyanidins are reported in skins and flesh of a single plum cultivar. In addition, total phenolic content (TPC) was measured with high values observed for all samples, especially for fruits skins with a TPC of 619.6 and 640.3 mg gallic acid equivalents/g extract respectively for apple and plum. Antioxidant potential using 2,2-diphenyl-1-picrylhidrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods were evaluated, with results showing also high values for all samples, especially again for fruit skins with IC50 of 4.54 and 5.19 µg/mL (DPPH) and 16.8 and 14.6 mmol TE/g (ORAC) respectively for apple and plum, indicating the potential value of these extracts. Significant negative correlation was found for both apple and plum samples between TPC and DPPH antioxidant values, especially for plum fruits (R = −0.981, p < 0.05) as well as significant positive correlation between TPC and ORAC, also especially for plum fruits (R = 0.993, p < 0.05) and between both, DPPH and ORAC antioxidant methods (R = 0.994, p < 0.05).Universidad de Costa Rica/[115-B4-515]/UCR/Costa RicaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuÃmicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologÃ
Curcumin Hybrid Lipid Polymeric Nanoparticles: Antioxidant Activity, Immune Cellular Response, and Cytotoxicity Evaluation.
Poor solubility and short biological half-life present a challenge that needs to be overcome in order to improve the recognized bioactivities of curcumin (CUR), the main phenolic compounds derived from the roots of Curcuma longa. However, drug delivery systems have proven to be an excellent strategy to improve and obtain greater bioavailability. Our previous studies on curcuminoid hybrid nanoparticles have shown promising results by significantly increasing the solubility of desmethoxycurcumin (DMC) and bisdemethoxycurcumin (BDM). In this contribution, we performed a detailed characterization of a CUR as well as in vitro and in vivo studies. The developed method produced CUR loaded nanoparticles with an average size of 49.46 ± 0.80. Moreover, the FT-IR analysis confirmed the encapsulation, and TEM images showed their spherical shape. The NP achieved an encapsulation efficiency greater than 99%. Further, the release studies found that the NPs obtained a significantly higher release than the pure compounds in water. In vivo delayed-type hypersensitivity (DTH) studies showed promising results by enhancing the immune activity response of CUR in NP compared to bulk CUR. Furthermore, we report a significant increase in antioxidant activity for CUR-NP in aqueous solution compared to free CUR. Finally, an important in vitro cytotoxic effect on gastric AGS and colon SW620 adenocarcinoma cell lines was found for CUR-NP while empty carrier nanoparticles are observed to exhibit low cytotoxicity, indicating the potential of these CUR-PLU NPs for further studies to assess their phytotherapeutic applications.National Laboratory of Nanotechnology (LANOTEC).Ministerio de Ciencia, Innovación, TecnologÃa y Telecomunicaciones (MICITT)Universidad de Costa Rica/[115-C0-001]/UCR/Costa RicaUniversidad de Costa Rica/[115-C1-515]/UCR/Costa RicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuÃmicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Farmaci
Polyphenolic QTOF-ESI MS characterization and the antioxidant and cytotoxic activities of Prunus domestica.
There is an increased interest in plum research because of their metabolites’ potential bioactivities. In this study, the phenolic profiles of Prunus domestica commercial cultivars (Methley, Pisardii and Satsuma) in Costa Rica were determined by Ultra Performance Liquid Chromatogra phy coupled with High Resolution Mass Spectrometry using a quadrupole-time-of-flight analyzer (UPLC-ESI-QTOF MS) on enriched phenolic extracts obtained through Pressurized Liquid Extraction (PLE) under acidic and neutral extraction conditions. In total, 41 different phenolic compounds were identified in the skin and flesh extracts, comprising 11 flavan-3-ols, 14 flavonoids and 16 hydrox ycinnamic acids and derivatives. Neutral extractions for the skins and flesh from all of the cultivars yielded a larger number of compounds, and were particularly rich in the number of procyanidin trimers and tetramers when compared to the acid extractions. The total phenolic content (TPC) and antioxidant potential using the DPPH and ORAC methods exhibited better results for neutral extracts with Satsuma skins and Methley flesh, which showed the best values (685.0 and 801.6 mg GAE/g extract; IC50 = 4.85 and 4.39 µg/mL; and 12.55 and 12.22 mmol TE/g extract, respectively). A Two-Way ANOVA for cytotoxicity towards AGS gastric adenocarcinoma and SW620 colon adenocar cinoma indicated a significant difference (p < 0.05) for PLE conditions, with better results for neutral extractions, with Satsuma skin delivering the best results (IC50 = 60.7 and 46.7 µg/mL respectively) along with Methley flesh (IC50 = 76.3 and 60.9 µg/mL, respectively). In addition, a significant positive correlation was found between TPC and ORAC (r = 0.929, p < 0.05), as well as a significant negative correlation (p < 0.05) between TPC and cytotoxicity towards AGS and SW620 cell lines (r = −0.776, and −0.751, respectively). A particularly high, significant, negative correlation (p < 0.05) was found between the number of procyanidins and cytotoxicity against the AGS (r = −0.868) and SW620 (r = −0.855) cell lines. Finally, the PCA clearly corroborated that neutral extracts are a more homogenous group exhibiting higher antioxidant and cytotoxic results regardless of the part or cultivar; therefore, our findings suggest that PLE extracts under neutral conditions would be of interest for further studies on their potential health benefits.Universidad de Costa RicaUCR::VicerrectorÃa de Docencia::Salud::Facultad de Medicina::Escuela de MedicinaUCR::VicerrectorÃa de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de QuÃmic
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