Effect of photostimulation through red LED light radiation on natural fermentation of table olives: An innovative case study with Negrinha the Freixo variety.

In this study, for the first time, red LED light radiation was applied to the fermentation process of table olives using the Negrinha de Freixo variety. Photostimulation using LED light emission (630 ± 10 nm) is proposed to shorten and speed up this stage and reduce time to market. Several physical-chemical characteristics and microorganisms (total microbial count of mesophilic aerobic, molds, yeasts, and lactic acid bacteria) and their sequence during fermentation were monitored. The fermentation occurred for 122 days, with two irradiation periods for red LED light. The nutritional composition and sensory analysis were performed at the end of the process. Fermentation under red LED light increased the viable yeast and lactic acid bacteria (LAB) cell counts and decreased the total phenolics in olives. Even though significant differences were observed in some color parameters, the hue values were of the same order of magnitude and similar for both samples. Furthermore, the red LED light did not play a relevant change in the texture profile, preventing the softening of the fruit pulp. Similarly, LED light did not modify the existing type of microflora but increased species abundance, resulting in desirable properties and activities. The species identified were yeasts - Candida boidinii, Pichia membranifaciens, and Saccharomyces cerevisiae, and bacteria - Lactobacillus plantarum and Leuconostoc mesenteroides, being the fermentative process dominated by S. cerevisiae and L. plantarum. At the end of fermentation (122 days), the irradiated olives showed less bitterness and acidity, higher hardness, and lower negative sensory attributes than non-irradiated. Thus, the results of this study indicate that red LED light application can be an innovative technology for table olives production.

Salvage cryotherapy for prostate cancer.

BACKGROUND: Most men diagnosed with prostate cancer will be candidates for active treatment and 20 to 50% of patients treated with organ preserving strategies recur within the prostate. Optimal treatment of recurrence is controversial. Prostate cryosurgery has been increasingly used as primary, recurrence and focal treatment for prostate cancer. METHODS: We analysed 55 patients submitted to cryotherapy as salvage treatment after recurrence. RESULTS: Study population presented with a mean age of 70.9 ± 6.2 years, mean initial PSA of 7.6 ng/ml and average prostate volume by ultrasound of 43.2 ± 14.7 grams. Mean follow-up was of 18.0 months. Biochemical free survival at one year of follow-up was of 85%. CONCLUSIONS: Cryotherapy can be an effective and safe treatment for recurrence after primary curative treatment failure.

Olive Oil Sensory Analysis as a Tool to Preserve and Valorize the Heritage of Centenarian Olive Trees.

In inland areas of Portugal and some regions of the Mediterranean basin, olive production is based on traditional olive groves, with low intensification, local cultivars, aged plants, and centenarian trees. These plants play a key role in the ecosystem, contributing to carbon sequestration and possessing a high genetic diversity, particularly important for selecting cultivars more resistant to climatic changes. Appreciation of the value of this genetic diversity implies genetic, morphological, and physicochemical characterization of centenarian trees, which is expensive and time-consuming. Sensory evaluation is also of utmost importance. Thus, in this study, centenarian olive trees were selected in the Côa Valley region, a UNESCO World Heritage site. The descriptive sensory profile of their extracted olive oils was established and used to cluster the oils, using hierarchical clustering analysis, and consequently the olive trees, into five groups with similar intensities of perceived olfactory-gustatory attributes. Each cluster revealed olive oils with unique sensory patterns, presumably due to similarities of the olive trees, confirming the potential of the proposed screening approach. The identification of sensorially homogeneous oil-tree groups would reduce the number of specimens needed for subsequent morphological, genetic, and chemical characterization, allowing a cost-effective and robust future evaluation procedure.

Freezing of edible flowers: Effect on microbial and antioxidant quality during storage.

Edible flowers are a new gourmet product; however, they are not always available all years. Thus, it is essential to find out technologies to guarantee this product for a longer time. Flowers of four species (borage [Borago officinalis], heartsease [Viola tricolor], kalanchoe [Kalanchoe blossfeldiana], and dandelion [Taraxacum officinale]) were subjected to freezing (in their natural form and in ice cubes) and analyzed in terms of visual appearance, the content of flavonoids, hydrolysable tannins, phenolics, antioxidant activity (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power), and microbial quality after storage for 1 and 3 months. Flowers in ice cubes showed similar appearance to fresh ones during the 3 months of storage, whereas frozen flowers were only equivalent up to 1 month with the exception of kalanchoe. Even though flowers in ice cubes showed good appearance after 3 months of storage, they had the lowest values of bioactive compounds and antioxidant activity. On the contrary, when frozen, the content of bioactive compounds maintained or even increased up to 1 month of storage compared to fresh flowers, except for borage. Furthermore, in both freezing treatments, the microorganisms' counts decreased or maintained when compared to fresh samples, except in dandelion. In general, both treatments may allow keeping the flowers after their flowering times. PRACTICAL APPLICATION: The market of edible flowers is increasing, although they are a very perishable product with short shelf-life. Edible flowers are stored in the cold (frozen or in ice cubes); however, the effect on the bioactive compounds and microbial quality that this treatment may have on borage (Borago officinalis), heartsease (Viola tricolor), kalanchoe (Kalanchoe blossfeldiana), and dandelion (Taraxacum officinale) flowers is unknown. So, the present study was conducted to increase the knowledge about the changes that freezing treatments may have in different edible flowers. The results of the present study underline that each flower has different behavior at frozen and ice cubes storage. However, freezing flowers maintain/increase the contents of bioactive compounds, while ice cubes not. Both treatments are effective in protecting flowers from microorganism growth. So, suggesting that both freezing treatments can be used as a preservative method and may allow keeping the flowers after their flowering times.

Volatile changes in cv. Verdeal Transmontana olive oil: From the drupe to the table, including storage.

This study focused on the volatile changes in cv. Verdeal Transmontana throughout the entire olive oil processing chain, from the drupe to olive oil storage up to 12 months, while correlating it with quality parameters and sensory quality. During crushing and malaxation, the volatiles formed were mainly "green-leaf volatiles" (GLVs), namely (E)-2-hexenal, hexanal, and 1-hexanol. Centrifugation and clarification steps increased the total volatile amounts to 130 mg kg-1. However, clarification also increased nonanal and (E)-2-decenal contents, two markers of oxidation, with a noticeable loss of phenolic compounds and oxidative stability. During storage, the total volatile amounts reduced drastically (94% at 12 months after extraction), together with the positive sensory attributes fruity, green, bitter, and pungent. Despite being classified as extra-virgin after one year of storage, peroxides and conjugated dienes were significantly higher while there was a reduction in antioxidant capacity as well as in phenolic compounds (less 50%) and oxidative stability (57%). The present work allowed concluding that the extraction process modulates the volatile composition of olive oil, with a concentration of volatiles at the clarification step. During storage, volatiles are lost, mainly eight months after extraction, leading to the loss of important sensory attributes.

By-product of Lavandula latifolia essential oil distillation as source of antioxidants.

The objective of this work was to evaluate the antioxidant properties of Lavandula latifolia waste obtained after essential oil distillation. Samples of 12 wild populations of the Lavandula genus collected between 2009 and 2010 were hydrodistilled and their by-products were analyzed using the Folin-Ciocalteu, free radical scavenging activity (2,2-diphenyl-1-picrylhydrazyl), and the ferric reducing antioxidant power (FRAP) methods. Rosmarinic acid, apigenin, and luteolin contents were analyzed by high-performance liquid chromatography-diode array detection. The mean of total phenolic content ranged from 1.89 ± 0.09 mg gallic acid equivalents/g dry weight to 3.54 ± 0.22 mg gallic acid equivalents/g dry weight. The average value of the half maximal effective concentration (EC50) for scavenging activity ranged from 5.09 ± 0.17 mg/mL to 14.30 ± 1.90 mg/mL and the variability of the EC50 in FRAP ranged from 3.72 ± 0.12 mg/mL to 18.55 ± 0.77 mg/mL. Annual variation was found among this samples and the environmental conditions of 2009 were found to be more favorable. The plants collected from Sedano showed the highest antioxidant power. Our results show that rosmarinic acid and apigenin in L. latifolia contributed to the antioxidant properties of the waste. In conclusion, the by-product of the distillation industry could be valorizing as a source of natural antioxidants.

Physicochemical Changes and Antioxidant Activity of Juice, Skin, Pellicle and Seed of Pomegranate (cv. Mollar de Elche) at Different Stages of Ripening.

In the present work, we investigate how the degree of ripeness (low, low-medium, medium and medium-high) affects the physical and compositional changes, as well as antioxidant properties of pomegranate fruit (cv. Mollar de Elche). The skin, pellicle, seed and juice were analysed. The fruit mass increased and the fruit skin became reddish (higher a* and lower h*) as the fruit ripening progressed. The lowest concentrations of flavonoids and hydrolysable tannins were recorded in skin and pellicles at medium-high maturity stage, which explains the decrease in the total phenols and reducing power during ripening of pomegranate. On the contrary, the highest concentration of flavonoids (165 mg of quercetin equivalents per 100 mL of juice) was determined in the juice at the most advanced ripening stage, concomitant with the highest total phenols (1695 mg of gallic acid equivalents per 100 mL of juice). Higher DPPH scavenging activity and an increase in the reducing power of juice were also observed during ripening. The trend of the above-mentioned properties allowed describing the fruit development and maturity.

Antioxidant activity and bioactive compounds of lettuce improved by espresso coffee residues.

The antioxidant activity and individual bioactive compounds of lettuce, cultivated with 2.5-30% (v/v) of fresh or composted espresso spent coffee grounds, were assessed. A progressive enhancement of lettuce's antioxidant capacity, evaluated by radical scavenging effect and reducing power, was exhibited with the increment of fresh spent coffee amounts, while this pattern was not so clear with composted treatments. Total reducing capacity also improved, particularly for low spent coffee concentrations. Additionally, very significant positive correlations were observed for all carotenoids in plants from fresh spent coffee treatments, particularly for violaxanthin, evaluated by HPLC. Furthermore, chlorophyll a was a good discriminating factor between control group and all spent coffee treated samples, while vitamin E was not significantly affected. Espresso spent coffee grounds are a recognised and valuable source of bioactive compounds, proving herein, for the first time, to potentiate the antioxidant pool and quality of the vegetables produced.

Influence of spike lavender (Lavandula latifolia Med.) essential oil in the quality, stability and composition of soybean oil during microwave heating.

Lipids oxidation is one of the main factors leading to quality losses in foods. Its prevention or delay could be obtained by the addition of antioxidants. In this sense the present work intend to monitor the protective effects of Lavandula latifolia essential oil during soybean oil microwave heating. To achieve the proposed goal quality parameters (free acidity, peroxide value, specific coefficients of extinction and ΔK), fatty acids profile, tocopherols and tocotrienols composition, antioxidant activity and oxidative stability were evaluated in soybean oil with and without spike lavender essential oils (EO) submitted to different microwave heating exposure times (1, 3, 5, 10 and 15 min; 1000 Watt) with a standard domestic microwave equipment. Microwave heating induced severe quality and composition losses, mainly above 3 min of microwave heating, regardless the sample tested. However, spike lavender EO addition counteracts the oxidation comparatively to control oils, by presenting enhanced values in quality parameters. A higher protection in unsaturated fatty acids loss was also observed as well as a higher antioxidant activity and oxidative stability. The microwave heating effects were clearly different in the samples with essential oils addition, allowing discrimination from plain soybean oils by a principal component analysis, being also capable to discriminate the different heating times tested within each sample.

Optimization of DNA extraction for RAPD and ISSR analysis of Arbutus unedo L. Leaves.

Genetic analysis of plants relies on high yields of pure DNA. For the strawberry tree (Arbutus unedo) this represents a great challenge since leaves can accumulate large amounts of polysaccharides, polyphenols and secondary metabolites, which co-purify with DNA. For this specie, standard protocols do not produce efficient yields of high-quality amplifiable DNA. Here, we present for the first time an improved leaf-tissue protocol, based on the standard cetyl trimethyl ammonium bromide protocol, which yields large amounts of high-quality amplifiable DNA. Key steps in the optimized protocol are the addition of antioxidant compounds-namely polyvinyl pyrrolidone (PVP), 1,4-dithiothreitol (DTT) and 2-mercaptoethanol, in the extraction buffer; the increasing of CTAB (3%, w/v) and sodium chloride (2M) concentration; and an extraction with organic solvents (phenol and chloroform) with the incubation of samples on ice. Increasing the temperature for cell lyses to 70 °C also improved both DNA quality and yield. The yield of DNA extracted was 200.0 ± 78.0 µg/µL and the purity, evaluated by the ratio A(260)/A(280), was 1.80 ± 0.021, indicative of minimal levels of contaminating metabolites. The quality of the DNA isolated was confirmed by random amplification polymorphism DNA and by inter-simple sequence repeat amplification, proving that the DNA can be amplified via PCR.

Cultivar effect on the phenolic composition and antioxidant potential of stoned table olives.

Stoned green table olives "alcaparras" prepared from five different cultivars (Cv. Cobrançosa, Madural, Negrinha de Freixo, Santulhana and Verdeal Transmontana) were investigated concerning their phenolic composition and antioxidant potential. From each cultivar, five independent lots were prepared. The phenolic profile was determined by HPLC/DAD at 280 nm, and antioxidant potential measured using the reducing power and scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals assays. Twelve phenolic compounds were identified, being hyrdoxytyrosol the most abundant one, followed by verbascoside and tyrosol. Cv. Cobrançosa and Santulhana reported higher content of phenolic compounds, with 165.76 and 163.66 mg/kg of fresh "alcaparras" table olives, respectively. Regarding antioxidant activity, Cv. Santulhana and Cobrançosa showed higher EC(50) values, lower than 1.40 and 0.48 mg/mL for reducing power and DPPH methods, respectively. Significant negative correlations were obtained between olive phenolics and EC(50) values from the antioxidant activity. The direct contact of the pulp with water, characteristic of this processing method, eliminates important hydrossoluble compounds, being the cultivar used an important determinant for the final "alcaparras" composition in terms of ingested phenolic compounds and antioxidant activity.

Olive oil stability under deep-frying conditions.

The suitability of different commercial olive oil categories for domestic frying was investigated. Oil samples were taken every 3h of frying and evaluated for free acidity, peroxide and p-anisidine values, specific extinction coefficients, oxidative stability, fatty acids, vitamin E, ß-carotene and total phenols, until the total polar compounds achieved the maximum legal value (25%). All olive oils were fried during more time than the commercial vegetable oil blend taken for comparison (from 24 to 27 h, against 15 h). The extra-virgin Protected Designation of Origin (PDO) olive oil was characterized by reduced levels of oxidation and hydrolysis, and superior amounts of minor antioxidant compounds. The "olive oil" commercial category behaves similarly, but "Cobrançosa" olive oils performance was slightly worse, and clearly different between years, highlighting the importance of blending different cultivars. The vegetable oil, despite containing significantly higher amounts of vitamin E, was highly susceptible to oxidation under frying conditions when compared to all olive oils. The results also show that the chemical composition of olive oils, particularly the amount of natural antioxidants, are important parameters in their predictive behavior along the frying process, but mostly that olive oil is clearly resistant to frying conditions, independently to the commercial category chosen.

Effect of microwave heating with different exposure times on physical and chemical parameters of olive oil.

This study reflects the effect of different microwave heating times (1, 3, 5, 10 and 15 min) on physical and chemical characteristics of three Portuguese olive oils from three protected designation of origin (PDO), "Azeite de Trás-os-Montes PDO", "Azeites da Beira Interior PDO", and "Azeite de Moura PDO". The parameters evaluated were free acidity, peroxide value, specific extinction coefficients (K232 and K270), color and chlorophylls and carotenoids content. A differential pulse voltammeter was also used to monitor the changes in alpha-tocopherol content. The results showed that microwave heating produce losses in the quality of the different analysed olive oils. The heating time did not promote the occurrence of hydrolysis in the samples since no changes in free acidity values were found. All other parameters were affected by exposure time in a similar way: in the first 3 min no marked changes were observed, after that the quality of the oil decrease significantly. The microwave heating time also affects the total chlorophylls, carotenoids and alpha-tocopherol contents which clearly decreased as long as the exposure time increases. After 15 min of heating the electrochemical signal, due to the alpha-tocopherol, disappear completely in the voltamogram.

Antioxidant properties, total phenols and pollen analysis of propolis samples from Portugal.

Pollen analysis, total phenols content and antioxidant activity were studied for the first time in Portuguese propolis samples from Bornes and Fundão regions. Total phenols content was determined by colorimetric assay and their amount was of 329 mg/g of GAE in Bornes sample and 151 mg/g of GAE in Fundão propolis. The antioxidant capacity of propolis extracts was assessed through the scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) and reducing power of iron (III)/ ferricyanide complex assays. A concentration-dependent antioxidative capacity was verified in DPPH and reducing power assays. Low values of EC50 on DPPH scavenging assay were obtained for Bornes and Fundão propolis (of 6.22 microg/mL and 52.00 microg/mL, respectively). For reducing power the values were 9.00 microg/mL, for Bornes propolis, and 55.00 microg/mL, for Fundão propolis. The high activity of propolis from Bornes could be related with their different pollen composition. The results obtained indicate that Portuguese propolis is an important source of total phenols showing antioxidant properties that could be beneficial for human health.

Total phenols, antioxidant potential and antimicrobial activity of walnut (Juglans regia L.) green husks.

The total phenols content and antioxidant and antimicrobial activities were studied in walnut (Juglans regia L.) green husks aqueous extracts of five different cultivars (Franquette, Mayette, Marbot, Mellanaise and Parisienne). Total phenols content was determined by colorimetric assay and their amount ranged from 32.61 mg/g of GAE (cv. Mellanaise) to 74.08 mg/g of GAE t (cv. Franquette). The antioxidant capacity of aqueous extracts was assessed through reducing power assay, scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and beta-carotene linoleate model system. A concentration-dependent antioxidative capacity was verified in reducing power and DPPH assays, with EC50 values lower than 1 mg/mL for all the tested extracts. The antimicrobial capacity was screened against Gram positive and Gram negative bacteria, and fungi. All the extracts inhibited the growth of Gram positive bacteria, being Staphylococcus aureus the most susceptible one with MIC of 0.1 mg/mL for all the extracts. The results obtained indicate that walnut green husks may become important in the obtainment of a noticeable source of compounds with health protective potential and antimicrobial activity.

Antioxidant activity and bioactive compounds of ten Portuguese regional and commercial almond cultivars.

The antioxidant properties of different almond cultivars (cv.), either regional (Casanova, Duro Italiano, Molar, Orelha de Mula and Pegarinhos cv.) or commercial (Ferraduel, Ferranhês, Ferrastar and Guara cv.) were evaluated through several chemical and biochemical assays: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of beta-carotene bleaching, inhibition of oxidative hemolysis in erythrocytes, induced by 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH), and inhibition of thiobarbituric acid reactive substances (TBARS) formation in brain cells, all used as models for the lipid peroxidation damage in biomembranes. The EC50 values were calculated for all the methods in order to evaluate the antioxidant efficiency of each almond cultivar. Bioactive compounds such as phenols and flavonoids were also obtained and correlated to antioxidant activity. The results obtained were quite heterogeneous, revealing significant differences among the cultivars assayed. Duro Italiano cv. revealed better antioxidant properties, presenting lower EC50 values in all assays, and the highest antioxidants contents. The protective effect of this cultivar on erythrocyte biomembrane hemolysis was maintained during 4h.

Chemical composition, and antioxidant and antimicrobial activities of three hazelnut (Corylus avellana L.) cultivars.

Hazelnut (Corylus avellana L.) is a very popular dry fruit in the world being consumed in different form and presentations. In the present work, three hazelnut cultivars (cv. Daviana, Fertille de Coutard and M. Bollwiller) produced in Portugal, were characterized in respect to their chemical composition, antioxidant potential and antimicrobial activity. The samples were analysed for proximate constituents (moisture, fat, crude protein, ash), nutritional value and fatty acids profile by GC/FID. Antioxidant potential was accessed by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and beta-carotene linoleate model system. Their antimicrobial capacity was also checked against Gram positive (Bacillus cereus, B. subtilis, Staphylococcus aureus) and Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). Results showed that the main constituent of fruits was fat ranging from 56% to 61%, being the nutritional value around 650 kcal per 100 g of fruits. Oleic was the major fatty acid varying between 80.67% in cv. F. Coutard and 82.63% in cv. Daviana, followed by linoleic, palmitic, and stearic acids. Aqueous hazelnut extract presented antioxidant activity in a concentration-dependent way, in general with similar behaviour for all cultivars. Hazelnut extracts revealed a high antimicrobial activity against Gram positive bacteria (MIC 0.1 mg/mL) showing a good bioactivity of these fruits.

Walnut (Juglans regia L.) leaves: phenolic compounds, antibacterial activity and antioxidant potential of different cultivars.

Different cultivars of walnut (Juglans regia L.) leaves (Cv. Lara, Franquette, Mayette, Marbot, Mellanaise and Parisienne) grown in Portugal, were investigated in what concerns phenolic compounds and antimicrobial and antioxidant properties. Phenolics analysis was performed by reversed-phase HPLC/DAD and 10 compounds were identified and quantified: 3- and 5-caffeoylquinic acids, 3- and 4-p-coumaroylquinic acids, p-coumaric acid, quercetin 3-galactoside, quercetin 3-pentoside derivative, quercetin 3-arabinoside, quercetin 3-xyloside and quercetin 3-rhamnoside. The antimicrobial capacity was screened against Gram positive (Bacillus cereus, B. subtilis, Staphylococcus aureus) and Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). Walnut leaves selectively inhibited the growth of Gram positive bacteria, being B. cereus the most susceptible one (MIC 0.1mg/mL). Gram negative bacteria and fungi were resistant to the extracts at 100mg/mL. Lara walnut leaves were also submitted to antibacterial assays using 18 clinical isolates of Staphylococcus sp. Antioxidant activity was accessed by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and beta-carotene linoleate model system. In a general way, all of the studied walnut leaves cultivars presented high antioxidant activity (EC(50) values lower than 1mg/mL), being Cv. Lara the most effective one.

Table olives from Portugal: phenolic compounds, antioxidant potential, and antimicrobial activity.

The phenolic compounds composition, antioxidant potential, and antimicrobial activity of different table olives from Portugal, namely, natural black olives "Galega", black ripe olive "Negrinha de Freixo", Protected Designation of Origin (PDO) "Azeitona de Conserva Negrinha de Freixo" olives, and "Azeitona de Conserva de Elvas e Campo Maior" Designation of Origin (DO) olives, were investigated. The analysis of phenolic compounds was performed by reversed-phase HPLC/DAD, and seven compounds were identified and quantified: hydroxytyrosol, tyrosol, 5-O-caffeoilquinic acid, verbascoside, luteolin 7-O-glucoside, rutin, and luteolin. The antioxidant activity was assessed by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals, and the beta-carotene linoleate model system. The antioxidant activity was correlated with the amount of phenolics found in each sample. The antimicrobial activity was screened using Gram-positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus) and Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans). PDO and DO table olives revealed a wide range of antimicrobial activity. C. albicans was resistant to all the analyzed extracts.