San Simon University

Cochabamba, Bolivia

San Simon University

Cochabamba, Bolivia
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Maldonado E.M.,Lund University | Maldonado E.M.,San Simon University | Salamanca E.,University Institute of La Paz | Gimenez A.,University Institute of La Paz | Sterner O.,Lund University
Brazilian Journal of Pharmacognosy | Year: 2016

Eleven compounds, 12-oxo-phytodienoic acid (1), persicogenin (2), eriodictyol 3ʹ4ʹ,7-trimethyl ether (3), phytol (4), spathulenol (5), 4-hydroxycinnamic acid (6), onopordin (7), 5,8,4ʹ-trihydroxy-7,3ʹ-dimethoxyflavone (8), quercetin (9), jaceosidin (10), and 8-hydroxyluteolin (11), were isolated from an ethanol extract of Lantana balansae Briq., Verbenaceae, that was found to possess antileishmanial activ-ity. The structures of the compounds were determined by NMR spectroscopy and HR mass spectrometry, and 1, 2, 3, 7, 8 and 9 were investigated for antiprotozoal activity toward promastigotes of Leishmania amazonensis and Leishmania braziliensis. Compound 1 was shown to be the most potent, with the IC50 values 2.0µM toward L. amazonensis and 0.68µM toward L. braziliensis, although less potent than the positive control Amphotericin B. All compounds have been reported previously, but this is the first report of the isolation of a cyclopentenone fatty acid (1) and flavanones (2 and 3) from a Lantana species. © 2016 Sociedade Brasileira de Farmacognosia. Published by Elsevier Editora Ltda. All rights reserved.

Perez-Rea D.,San Simon University | Perez-Rea D.,Lund University | Zielke C.,Lund University | Nilsson L.,Lund University
Journal of Chromatography A | Year: 2017

Starch and hence, amylopectin is an important biomacromolecule in both the human diet as well as in technical applications. Therefore, accurate and reliable analytical methods for its characterization are needed. A suitable method for analyzing macromolecules with ultra-high molar mass, branched structure and high polydispersity is asymmetric flow field-flow fractionation (AF4) in combination with multiangle light scattering (MALS) detection. In this paper we illustrate how co-elution of low quantities of very large analytes in AF4 may cause disturbances in the MALS data which, in turn, causes an overestimation of the size. Furthermore, it is shown how pre-injection filtering of the sample can improve the results. © 2017 Elsevier B.V.

Maldonado E.M.,Lund University | Maldonado E.M.,San Simon University | Svensson D.,Lund University | Oredsson S.M.,Lund University | Sterner O.,Lund University
Scientia Pharmaceutica | Year: 2014

Two new eudesmane derivatives (3 and 8) were isolated from the ethanol extract of the aerial parts of Kaunia lasiophthalma Griseb, together with 14 known eudesmane, germacrane, and guaiane sesquiterpenes, and four flavones. The structures and relative configurations of all the compounds were established by NMR spectroscopy and high-resolution mass spectrometry. The anticancer activity of sesquiterpenes 1, 3, 6-9, 11, 12, 14, and 16 was evaluated in vitro with the breast cancer cell lines HCC1937, JIMT-1, L56Br-C1, MCF-7, and SK-BR-3, and compared with the cytotoxicity in the non-cancerous breast epithelial cell line MCF-10A. All compounds were found to possess anticancer activity, and compound 1 was the most potent in all of the investigated cancer cell lines with IC50 values ranging between 2.0 and 6.2 μM. In order to demonstrate the importance of the α-methylene-γ-lactone/ester moiety present in all compounds for the effects on the cells, the methyl cysteine adduct 21 was prepared from 9 and found to be inactive or considerably less potent. © Maldonado et al.

Lazarte C.E.,Lund University | Lazarte C.E.,San Simon University | Encinas M.E.,San Simon University | Alegre C.,San Simon University | Granfeldt Y.,Lund University
Nutrition Journal | Year: 2012

Background: Improvement of traditional methods for dietary assessment is necessary, especially in rural areas where it is more difficult to succeed with self-reporting methods. This study presents and validates a method for improving accuracy when measuring food and nutrient intake of individuals in rural areas. It is called the "Food photography 24-h recall method" (FP 24-hR) and is a modified 24-h recall with the addition of a digital food photography record and a photo atlas. Methods. The study was carried out in a rural area in the tropical region of Bolivia; 45 women participated. Validation of the method was made by comparing it with a reference method, the Weighed Food Record (WFR). During the FP 24-hR, digital photographs were taken by the subjects of all food consumed during a day and a 24-h recall questionnaire was conducted by an interviewer. An estimate of the amount of food consumed was made using a photo atlas and the photographs taken by the subjects. For validation, comparison was made between the calculations, by both methods, of the levels of food, and nutrient, intake. Results: The comparison was made in 10 food categories; most of which were somewhat underestimated from -2.3% (cassava) to -6.8% (rice), except for beverages (+1.6%) and leafy vegetables (+8.7%), which were overestimated. Spearman's correlation coefficients were highly significant (r from 0.75 for eggs to 0.98 for potato and cassava). Nutrient intakes calculated with data from both methods showed small differences from -0.90% (vitamin C) to -5.98% (fat). Although all nutrients were somewhat underestimated, Pearson§ssup§′§esup§s coefficients are high (>0.93 for all) and statistically significant. Bland Altman analysis showed that differences between both methods were random and did not exhibit any systematic bias over levels of food and nutrient intake, with acceptable 95% limits of agreement. Conclusion: The FP 24-hR exhibits acceptable differences when compared with a WFR, digital photos are useful as a memory aid for the subjects during 24-h recall and as an estimation tool. The method is suitable for assessing dietary intake among rural populations in developing countries. © 2012 Lazarte et al.; licensee BioMed Central Ltd.

Maldonado E.M.,Lund University | Maldonado E.M.,San Simon University | Svensson D.,Lund University | Oredsson S.M.,Lund University | Sterner O.,Lund University
Phytochemistry Letters | Year: 2014

A phytochemical study of the flowers of Kaunia lasiophthalma G. (Asteraceae) yielded a novel triterpene (1) together with several known sesquiterpenoids. The structure of the new compound was elucidated by analysis of the spectroscopic data. The biosynthetic origin of 1 is proposed to be a dimerization of an oxidized derivative (3) of the germacrane sesquiterpene costunolide (2), also present in the flowers. The anticancer activity of 1 in the five breast cancer cell lines HCC1937, JIMT-1, L56Br-C1, MCF-7 and SK-BR-3 was compared with the cytotoxicity in the normal-like breast epithelial cell line MCF-10A. 1 exhibited high cytotoxicity in all investigated cancer cell lines with IC50 values ranging from 0.67 to 7.0 μM, although it is lacking selectivity as the MCF-10A cells were almost as sensitive. © 2014 Phytochemical Society of Europe.

Romero M.,San Simon University | Ballesteros N.,San Simon University | Lucana V.,San Simon University
Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2014 | Year: 2014

The present paper illustrates the experimental assessment of scouring and deposition processes around several arrays of permeable gabion groynes with a number of attack angles to the flow. Four scaled T-head shape groynes made of stone were placed in a flume with a constant bed slope and a single steady discharge for submerged conditions. Uniform fine was used as mobile bed. Five attack angles and two separation lengths in between structures were tested. Results show that for each specific separation length, different attack angles produce the minimum scour depths and eroded volumes, largest deposited volumes in between structures, and less scouring velocities at three considered control sections. Therefore, individual attack angles were identified for specific tasks to be better accomplished by such arrays. However, it is acknowledged that more tests with different separation lengths or different sediment sizes of the bed are needed to improve the obtained conclusions. © 2014 Taylor & Francis Group, London.

Lopez R.R.,San Simon University | Vincent L.,Wageningen University | Rap E.,International Water Management Institute
International Journal of Water Resources Development | Year: 2015

The expansion of the Totora Khocha dam-based irrigation system in the Pucara watershed is a case of planned re-engineering of a closing watershed. This article shows how, when irrigation systems expand in space and across boundaries to capture new water, they also involve new claims by existing and emergent users. This results in complex processes of design, contestation and negotiated redesign, where irrigation projects are being produced by the negotiated construction of water networks. Therefore, the design process in a closing watershed is better approached as a dynamic and negotiated process of engineering than as a prescriptive mode of network building. © 2014, © 2014 Taylor & Francis.

Fernandez C.,Lund University | Rojas C.C.,Lund University | Rojas C.C.,San Simon University | Nilsson L.,Lund University
International Journal of Biological Macromolecules | Year: 2011

In this paper we investigate the size, structure and scaling relationships in glycogen isolated from five different animal sources. For this purpose a versatile fractionation technique, asymmetrical flow field-flow fractionation (AsFlFFF), coupled to multi-angle light scattering, is utilized. For determination of the average degree of branching 1H NMR is utilized. The results give a detailed insight into the physico-chemical properties of glycogen over the whole size distribution. The results show that glycogen is a hyper branched macromolecule with wide size distributions, and in some samples two major populations are clearly observed which most likely correspond to β- and α-particles of glycogen. The results also illustrates that glycogen is a polysaccharide showing rather diverse conformational properties, over the size distribution, depending on its origin and the extraction procedure. The ratio between root-mean-square radius and hydrodynamic radius varies depending of both sample origin the molar mass of the macromolecules, reflecting differences in conformation and scaling within the size distribution. Thus, a priori assumptions regarding the r rms/r h are difficult to make and r rms/r h based on average properties give an incomplete description of the properties. Furthermore, the results display the strength of the apparent density (as obtained from AsFlFFF-MALS-RI) as a characterization parameter for scaling in disperse macromolecules. © 2011 Elsevier B.V.

Lazarte C.E.,Lund University | Lazarte C.E.,San Simon University | Carlsson N.-G.,Chalmers University of Technology | Almgren A.,Chalmers University of Technology | And 2 more authors.
Journal of Food Composition and Analysis | Year: 2015

The content of zinc, iron, calcium and phytate in the 16 most consumed foods from 5 villages in a tropical rural area of Bolivia was analyzed. The food items were selected according to a completed food frequency questionnaire. Minerals were analyzed by atomic absorption and phytates by HPIC chromatography. The molar ratios of phytate:mineral are presented as indication of the mineral bioavailability. Within the analyzed food, quinoa is a potential source of minerals: zinc 3.65, iron 5.40 and calcium 176. mg/100. g; however, it also has the highest content of phytate 2060. mg/100. g. Cereals and legumes showed high concentration of phytates (from 142 to 2070. mg/100. g), roots and tubers have lower concentrations (from 77 to 427. mg/100. g). In general, both phytate contents and molar ratios Phy:Zn (phytate:zinc), Phy:Fe (phytate:iron) and Phy:Ca (phytate:calcium) in most of the analyzed foods were at levels likely to inhibit the absorption of these minerals. Significant positive associations (. p<. 0.01) were found between the level of phytate and minerals in food, for zinc (. r=. 0.714), iron (. r=. 0.650) and calcium (. r=. 0.415). The results compared to data from USA or from Bolivia showed some discrepancies, confirming the need for more reliable data for dietary evaluations and interventions. © 2015 Elsevier Inc.

PubMed | Lund University and San Simon University
Type: | Journal: Food & nutrition research | Year: 2015

Zinc deficiency is a significant problem, in developing countries and in vegetarians, which can be caused by plant-based diets. Thus, dietary strategies, such as fermentation, to improve zinc bioavailability of diets should be investigated.To improve zinc bioavailability in a plant-based diet by the inclusion of fermented food.Cassava tubers were fermented and made to replace the unfermented cassava in a basal plant-based diet, and compared with plant-based diets with and without zinc supplement. The zinc bioavailability of the diets was evaluated in Wistar rats that were fed these diets for 28 days. The evaluation was for zinc apparent absorption (ZnAA), serum zinc levels, and zinc deposits in liver and femur; in addition, the feed efficiency ratio (FER) of the diets and femur weight (FW) of the rats were evaluated.During the cassava fermentation, lactic acid increased and pH decreased (from 6.8 to 3.9), which is favorable for native phytase activity, resulting in a 90.2% reduction of phytate content in cassava. The diet containing fermented cassava showed significantly higher levels of ZnAA, FER, and FW (p<0.001). Moreover, the zinc levels in serum and femur were significantly higher (p<0.001) compared with the results of the diet with unfermented cassava. The results clearly show a higher zinc bioavailability in the diet containing fermented cassava and are comparable with the results obtained with the plant-based diet with zinc supplement.In conclusion, the fermentation of cassava reduces the phytate content. The diet containing the fermented cassava represents a better nutritional alternative than the diet with unfermented cassava and is comparable with the zinc-supplemented diets.

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