Purification process for MUFA- and PUFA-based monoacylglycerols from edible oils.

Important health benefits have been attributed to monoacylglycerols (MAGs) due to their various physiological functions, owing to which they become candidates for use as functional foods in order to prevent the onset of certain diseases such as colon cancer. In this work, six edible oils, namely: olive, linseed, sunflower, evening primrose, DHASCO® and ARASCO® have been processed to obtain different MUFA- and PUFA- based MAGs. First, the oils were hydrolyzed by means of an enzymatic process using porcine pancreatic lipase and then the reaction products were fractionated by using a liquid chromatography column containing silica gel as stationary phase in order to purify the MAGs-enriched fraction. A second chromatography process was performed using silver nitrate coated silica gel as stationary phase, in order to obtain the different MUFA- and PUFA-based MAGs from the corresponding oils. Overall, MAGs based on oleic, linoleic, α-linolenic, γ-linolenic, arachidonic and docosahexaenoic acids have been isolated in high yields and purities (92.6, 97.4, 95.3, 90.9, 100 and 95.3% purity, respectively). Positional distribution was determined by means of 1H NMR, which revealed a mix of 1(3) and 2-MAGs in variable proportions in the different MAGs.

Phytochemical Composition and Antitumor Activities of New Salad Greens: Rucola (Diplotaxis tenuifolia) and Corn Salad (Valerianella locusta).

D. tenuifolia and V. locusta, two greens, were analyzed for active compounds and antitumor actions on colorectal cancer cells. Phenolics were determined by UHPLC-Orbitrap-MS; carotenoids and glucosinolates by HPLC-MS; and sterols and fatty acids by gas-liquid chromatography (GLC). For antitumor effects, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) tests were run on HT-29 colorectal cancer cells, and in CCD-18 untransformed enterocyte cells. Six main carotenoids were identified in both vegetables, while total carotenoids accounted for 3520 and 2970 µg · g(-1) dry weight in D. tenuifolia and V. locusta, respectively. Six phenolics were detected in D. tenuifolia (68,600 µg · g(-1) dry weight) and five in V. locusta (139,000 µg · g(-1) dry weight). Three glucosinolates (GSL) were found in D. tenuifolia (1960 µg · g(-1) dry wt. total). Low-polarity extracts from V. locusta and D. tenuifolia showed IC50 ~ 150 and ~200 µg · mL(-1) on HT-29 cells, while both plants lacked actions on CCD-18 cells. V. locusta inhibited HT-29 cancer cells viability more efficiently than D. tenuiofolia, but induced less cytotoxicity. This work highlights the importance of functional foods for colorectal cancer prevention.

Effect of sublethal concentrations of waterborne copper on lipid peroxidation and enzymatic antioxidant response in Gambusia holbrooki.

The aim of the current research was to assess the possible influence of copper sulphate contamination on the antioxidant enzymatic defenses and lipid peroxidation (LPO) in the mosquitofish (Gambusia holbrooki). Quadruplicated lots of this fish were exposed to three increasing sub-lethal concentrations of Cu (0.10; 0.17 and 0.25mgCu/L) and a control without Cu for 20 days. Previous to laboratory acclimation, 8 fish were taken to define the initial population. At the end of the trials, 12 fish/sex/treatment were sampled for the determination of levels of copper in gills, metallothioneins (MTs) content, total lipids, fatty acids profiles and antioxidant enzymatic activity, as well as lipid peroxidation. Most of the antioxidant enzymatic defenses assayed were not activated and lipid peroxidation decreased significantly in fish exposed to any concentration of copper applied. This leads us to presume the existence of a protective mechanism against peroxidation other than the enzymatic antioxidant defense, which could be related to the observed increase of copper content in the gills.

Gamma-linolenic acid from Cape Verdian Boraginaceae.

The distribution of gamma-linolenic acid (GLA) was studied in the seed oil of six Cape Verdian Boraginaceae. The GLA ranges from trace levels in the three Heliotropum surveyed to 22.2% on saponifiable oil in Echium stenosiphon. All Echium species had GLA percentages in their seed oil around 20%. Echium seeds yield saponifiable oil from 15.8% (E. stenosiphon) to 17.3% (E. hypertropicum).

Fatty acids and carotenes in some ber (Ziziphus jujuba Mill) varieties.

Several jujube varieties from the southeast of Spain were analyzed for fatty acid and carotene contents. Triglycerides having medium-chain fatty acids were most abundant in all samples. The main fatty acids were 12:0 (18.3 +/- 9.97), 10:0 (12.5 +/- 19.0), 18:2n6 (9.27 +/- 7.26), 16:1n7 (8.50 +/- 5.77), 16:0 (7.25 +/- 4.35), and 18:1n9 (5.34 +/- 2.52) on total saponifiable oil. The fruits yield 1.33 +/- 0.17 g/100 g saponifiable oil on a dry weight basis. Fatty acid profiles of fruits were found to be influenced by their developmental stage. Multivariable data analyses show that the samples could be grouped on the basis of their fatty acid content. Carotenes were found to be in good agreement with other fruits, varying from 4.12 to 5.98 mg/100 g on a dry weight basis. The contribution to vitamin value reach a mdium of 38 microg RE/100 g on a fresh weight basis.

Occurrence and characterization of oils rich in gamma-linolenic acid (III): the taxonomical value of the fatty acids in Echium (Boraginaceae).

Fourteen species of the genus Echium (Fam. Boraginaceae) collected in the Macaronesia were surveyed in a search for high levels of gamma-linolenic acid (GLA, 18:3omega6) in the seed oil. High amounts of this fatty acid were found in all of them, ranging from 18.85% (E. pitardii var. pitardii) to 27.42% (E. gentianoides) on total seed fatty acids. The GLA content related to total seed weight was also significant, ranging from 1.26% (E. handiense) to 8.22% (E. gentianoides). In addition, considerable amounts of stearidonic acid (SA, 18:4omega3) were detected, ranging from 3.78% (E. bonnetii var. bonnetii) to 8.81% (E. pininana) on total fatty acids. Besides all the perennial species, the four herbaceous Echium taxa endemic to the Macaronesia also showed high GLA percentages. This is in contrast to the low GLA level found in continental Echium species, all of them bearing an herbaceous habit. These results are in good agreement with the available genetic data and show the ability of GLA to discriminate between Macaronesian and continental Echium species. The analysis of five other Macaronesian species belonging to plant families rich in GLA are also reported.

Biomass nutrient profiles of the microalga Nannochloropsis.

The nutritional composition of the marine eustigmatophyte Nannochloropsis spp. cultured in an indoor chemostat under continuous illumination was analyzed. Proximate composition, (moisture, ash, crude protein, available carbohydrates, fiber, lipids, and energy), nitrate, nucleic acid, mineral element (Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Pb, Cd, Cr, Ni, Co, and S), fatty acid, and pigment (carotenoids and chlorophyll) concentrations were determined. On average, the biomass contained 37.6% (w/w) available carbohydrates, 28.8% crude protein, and 18.4% total lipids. Mineral in 100 g of dry biomass were as follows: Ca (972 mg), K (533 mg), Na (659 mg), Mg (316 mg), Zn (103 mg), Fe (136 mg), Mn (3.4 mg), Cu (35.0 mg), Ni (0.22 mg), and Co (<0.1 mg). Toxic heavy metal contents (Cd and Pb) were negligible. Fatty acid content was as follows (on percent dry weight): 0.6% of 14:0, 5.0% of 16:0; 4.7% of 16:1omega7, 3.8% of 18:1omega9, 0.4% of 18:2omega6; 0.7% of 20:4omega6, and 2.2% of 20:5omega3. Nutrient composition of the biomass was highly influenced by residence time in the photobioreactor. The biomass harvested for short residence times was richer in protein and eicosapentaenoic acid than biomass harvested for high residence time.

Occurrence and characterization of oils rich in gamma-linolenic acid part II: fatty acids and squalene from Macaronesian Echium leaves.

Leaves from 25 Macaronesian Echium (Boraginaceae) species have been surveyed for hydrocarbon compounds. These plants were previously reported as the major source of gamma-linolenic acid so far found in nature. In addition, six European Echium species and the common Borago officinalis have been analysed for comparative purposes. High squalene amounts were found in all Echium plants from the Macaronesia, ranging from 3.73%, in E. simplex to 20.1% in E. fastousum. Squalene was almost absent from all European Echium species, and the same is true for B. officinalis. The relatively high oil content (2.27%) in leaves of E. fastuosum raises the total squalene amount to about 0.46% within this tissue. The main fatty acid component in the leaf was alpha-linolenic acid (ALA, 18:3omega3), ranging in the Macaronesian Echium from 9.32% in E. acanthocarpum to 54.45% in E. simplex. Possible utilisation of these plants as a commercial source of squalene and hypotheses about its physiological role in the plant are discussed.

Occurrence and characterization of oils rich in gamma-linolenic acid Part I: Echium seeds from Macaronesia.

Nineteen species of the genus Echium (Fam. Boraginaceae) collected in Macaronesia were surveyed in a search for new sources of gamma-linolenic acid (GLA, 18:3omega6). High amounts of this acid were found in all of them, ranging from 9.15% (E. plantagineum) to 26.31% (E. callithyrsum) of total seed fatty acids. The amounts of GLA related to total seed weight were also significant, ranging from 1.77% (E. sventenii) to 5.02% (E. nervosum). In addition, considerable amounts of stearidonic acid (SA, 18:4omega3) were detected, ranging from 3.03% (E. auberianum) to 12.94% (E. plantagineum) of total fatty acids. These data allow us to consider tile members of the genus Echium from Macaronesia as one of the richest sources of gamma-linolenic acid found so far in nature. The results obtained from multivariable data analysis and the taxonomic relationships among the species is discussed.

Eicosapentaenoic and arachidonic acids purification from the red microalga Porphyridium cruentum.

The polyunsaturated fatty acids (PUFA) eicosapentaenoic and arachidonic acids (EPA and AA), which have several pharmaceutical properties, have been purified from the red microalga Porphyridium cruentum. The process consists of only four main steps: (i) simultaneous extraction and saponification of the microalgal biomass; (ii) urea inclusion method (iii) PUFA esterification (iv) argentated silica gel column chromatography of the urea concentrate. Total AA and EPA recoveries reached 39.5% and 50.8% respectively for a purity approximately 97% for both fatty acids. Therefore, recovery of highly pure PUFA could be improved in organisms that are rich in two or more fatty acids of interest. The results of several procedures for AA and EPA recovery from several authors by using this microalga were compared.