Analytical Tools Used to Distinguish Chemical Profiles of Plants Widely Consumed as Infusions and Dietary Supplements: Artichoke,Milk Thistle,and Borututu

Artichoke, borututu, and milk thistle are three medicinal plants widely consumed as infusions or included in dietary supplements (e.g., pills and syrups). Despite the high consumption of these plants, studies on their nutritional value and primary metabolites are scarce, with their composition in secondary metabolites such as phenolic compounds being only reported. Therefore, their nutritional value was assessed, and analytical tools (liquid and gas chromatography coupled to different detectors) were used to distinguish their chemical profiles according to their hydrophilic (sugars and organic acids) and lipophilic (fatty acids and tocopherols) components. Chromatographic techniques are important analytical tools used in the identification and quantification of several molecules, also being a standard requirement to distinguish different profiles. Borututu gave the highest energetic value with the highest content of carbohydrates and fat, sucrose and total sugars, shikimic and citric acids, and α-, β-, δ-, and total tocopherols. Artichoke had the highest ash and protein contents, oxalic acid, SFA (mainly palmitic acid), and γ-tocopherol, and also the best n-6/n-3 ratio. Milk thistle showed the highest levels of fructose and glucose, quinic acid and total organic acids, and PUFA, mainly linoleic acid, and the best PUFA/SFA ratio. The hydrophilic compounds identified in the studied plants, mostly sugars, are responsible for the energy contribution of their widely consumed infusions. Otherwise, the bioactivity of lipophilic compounds, namely, unsaturated fatty acids and tocopherols, is lost in those preparations but can be recovered in dietary supplements based on the plants. As far as we know, this is the first report on the detailed composition of the three plants regarding their nutritional features.     

Determination of Phenolic Compounds in Artichoke,Garlic and Spinach by Ultra-High-Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

Phenolic compounds were determined in artichoke (Cynara scolymus), garlic (Allium sativium) and spinach (Spinacia oleracea) using a single method based on simple extraction and ultra-high-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). Several compounds belonging to different families, such as phenolic acids, isoflavones, flavones and flavonols, were determined. The analytical procedure was validated in all the matrices, obtaining recoveries ranging from 60 to 120 % with reproducibility values (expressed as relative standard deviations (RSDs)) lower than 26 %. Limits of quantification (LOQs) were always equal to or lower than 50 μg/kg, except to kaempferol and its glucosides in spinach (LOQs?=?75 μg/kg). Artichoke showed higher concentration of phenolic compounds (837.2 mg/kg dry weight (DW)) than garlic (26.5 mg/kg DW) or spinach (64.5 mg/kg DW). Apigenin 7-O-glucoside (from 147.0 to 722.7 mg/kg DW) was found to be the major flavonoid in all samples of artichoke investigated, while chlorogenic acid, whose concentration ranged from 37.8 to 734.7 mg/kg DW, is the major phenolic acid in this matrix. Regarding garlic, caffeic acid (from 1.7 to 28.3 mg/kg DW) and quercetin (from 9.0 to 18.9 mg/kg DW) were the compounds detected at higher concentrations, although in general the total content was very low in relation to other matrices. In relation to spinach, ferulic acid was the major phenolic compound, and its concentration ranged from 18.0 to 41.4 mg/kg DW.     

Free-radical scavenging capacity and reducing power of wild edible mushrooms from northeast Portugal: Individual cap and stipe activity

The antioxidant properties of two wild edible mushroom species from the northeast of Portugal, Lactarius deliciosus (L.) Gray and Tricholoma portentosum (Fr.) Quél., were evaluated. Methanolic extracts from the entire mushroom, the cap and the stipe, separately, were screened for their reducing power and free radical scavenging capacity by chemical assays. The total phenolic content was determined, in order to assess its effect on the extract’s antioxidant activity. Both two species showed antioxidant potential; but L. deliciosus proved to be more active. The portion of the mushroom used had an influence on the results obtained, with the cap methanolic extracts exhibiting the greatest antioxidant effect.     

Protein breakdown during the preparation of frozen batter-coated squid rings

The objective of this paper was to study the main chemical and microstructural changes in squid proteins during processing as a frozen batter-coated product using different coatings. Protein bands of the squid and of the batters used for coating were studied using SDS-PAGE. It is concluded that it is not only the proteins of the layer of batter, which are directly exposed both to the frying oil and to freezing temperatures, that deteriorate during the preparation process, the protein fraction of the squid substrate, mainly the myofibrillar proteins, is also degraded. At a microstructural level, big voids are generated during freezing as a consequence of the packing of the fibres, although the size of these voids decreases after final frying. After this step of the process, the central sarcoplasm is still visible but has been altered by coagulation of the sarcoplasmic proteins and the sarcolemma is observed to be separate from the myofibrillar package.     

Antimicrobial susceptibility of Listeria monocytogenes isolated from food and clinical cases in Navarra, Spain

The susceptibility of 440 Listeria monocytogenes strains isolated from food (n=401) and clinical cases (n=39) between 1995 and 2005 was determined by standard agar dilution and E-test methods. Antimicrobial drugs currently used in veterinary and human therapy were tested, and they included penicillin G, ampicillin, cephalothin, gentamicin, chloramphenicol, tetracycline, doxycycline, trimethoprim, erythromycin, and clindamycin. The sensitivity of strains was established using Clinical and Laboratory Standards Institute (formerly NCCLS) breakpoints and MIC50 (the MIC for 50% of the strains) to MIC90 values. In general, isolates were susceptible to the majority of the antimicrobials tested, including beta-lactamics and aminoglycosides, which are normally used in the treatment of listeriosis. Resistance to tetracycline and doxycycline was found in five strains isolated from fresh trout belonging to the same fish farm. Molecular analysis by restriction endonuclease analysis showed a similar profile, suggesting the persistence of a strain well adapted to the presence of tetracycline in the environment of a fish farm, which is frequently used in aquaculture in order to prevent infections of fish.     

Combined bioaugmentation and biostimulation to cleanup soil contaminated with high concentrations of atrazine

We developed a joint bioaugmentation and biostimulation approach for the clean up of soil contaminated with high (168.7 and 337.4 microg g(-1)) concentrations of the herbicide atrazine (2-chloro-4-(ethylamino)-6-isopropylamino-s-triazine). Pseudomonas sp. strain ADP (P. ADP) was used for bioaugmentation (approximately 10(7) cells g(-1) soil), and citrate (concentration range 5.8-40 mg g(-1) soil) and succinate (6.2-30.8 mg g(-1)) were used for biostimulation. The study soil had indigenous potential for atrazine mineralization (54.4 +/- 2% of 168.7 microg g(-1) mineralized after 67 day), but rapid mineralization only took place after a prolonged acclimation phase (approximately 28 days). Inoculation with P. ADP alone resulted in a limited improvement in mineralization (e.g., 30.6 +/- 1% mineralization of 168.7 microg g(-1) of atrazine in inoculated soil cf. < 0.5% in noninoculated in 7 days). Quantification of surviving numbers of P. ADP revealed a 10-fold decline from initial levels. However, bioaugmentation together with citrate or succinate biostimulation markedly increased P. ADP cell survival and atrazine mineralization (e.g., addition of 11.6 mg g(-1) of citrate increased mineralization of 337.4 microg g(-1) of atrazine from < 2 to 79.9 +/- 1% in 13 days). A critical parameter in determining the extent of atrazine mineralization by P. ADP was C(s):N(atz) (soluble carbon to atrazine nitrogen ratio): C(s):N(atz) > 40 was required for maximal atrazine mineralization. We suggest our observations may be used as a framework for rational bioremediation of field soils contaminated with atrazine.