Gloeothece sp.—exploiting a new source of antioxidant, anti-inflammatory, and antitumor agents

Bioactive lipidic compounds of microalgae, such as polyunsaturated fatty acids (PUFA) and carotenoids, can avoid or treat oxidation-associated conditions and diseases like inflammation or cancer. This study aimed to assess the bioactive potential of lipidic extracts obtained from Gloeothece sp.–using Generally Recognized as Safe (GRAS) solvents like ethanol, acetone, hexane:isopropanol (3:2) (HI) and ethyl lactate. The bioactive potential of extracts was assessed in terms of antioxidant (ABTS•+, DPPH•,• NO and O2• assays), anti-inflammatory (HRBC membrane stabilization and Cox-2 screening assay), and antitumor capacity (death by TUNEL, and anti-proliferative by BrdU incorporation assay in AGS cancer cells); while its composition was characterized in terms of carotenoids and fatty acids, by HPLC-DAD and GC-FID methods, respectively. Results revealed a chemopreventive potential of the HI extract owing to its ability to: (I) scavenge- NO• radical (IC50, 1258 ± 0.353 µg·mL-1 ); (II) inhibit 50% of COX-2 expression at 130.2 ± 7.4 µg·mL-1; (III) protect 61.6 ± 9.2% of lysosomes from heat damage, and (IV) induce AGS cell death by 4.2-fold and avoid its proliferation up to 40% in a concentration of 23.2 ± 1.9 µg·mL-1 . Hence, Gloeothece sp. extracts, namely HI, were revealed to have the potential to be used for nutraceutical purposes.This research was supported by national funds through FCT—Foundation for Science and Technology within the scope of UIDB/04423/2020, granted to CIIMAR and UIDB/00511/2020 granted to LEPABE funded by national funds through FCT/MCTES (PIDDAC)

Adjusted Light and Dark Cycles Can Optimize Photosynthetic Efficiency in Algae Growing in Photobioreactors

Biofuels from algae are highly interesting as renewable energy sources to replace, at least partially, fossil fuels, but great research efforts are still needed to optimize growth parameters to develop competitive large-scale cultivation systems. One factor with a seminal influence on productivity is light availability. Light energy fully supports algal growth, but it leads to oxidative stress if illumination is in excess. In this work, the influence of light intensity on the growth and lipid productivity of Nannochloropsis salina was investigated in a flat-bed photobioreactor designed to minimize cells self-shading. The influence of various light intensities was studied with both continuous illumination and alternation of light and dark cycles at various frequencies, which mimic illumination variations in a photobioreactor due to mixing. Results show that Nannochloropsis can efficiently exploit even very intense light, provided that dark cycles occur to allow for re-oxidation of the electron transporters of the photosynthetic apparatus. If alternation of light and dark is not optimal, algae undergo radiation damage and photosynthetic productivity is greatly reduced. Our results demonstrate that, in a photobioreactor for the cultivation of algae, optimizing mixing is essential in order to ensure that the algae exploit light energy efficiently

Antinociceptive and anti-inflammatory effects of novel dietary protein hydrolysate produced from whey by proteases of Cynara cardunculus

Antinociceptive and anti-inflammatory effects of a peptide concentrate mix (PepC) obtained from whey protein, via hydrolysis with cardosins from Cynara cardunculus, was tested in vivo. The antinociceptive effect was assessed using writhing, hot-plate and formalin tests in mice, and the anti-inflammatory effect using the paw oedema test. PepC at 300 mg kg(-1) bw conveyed a significant result in the writhing test when co-administered with 1 and 3 mg kg(-1) bw indomethacin, similar to administration of higher doses of indomethacin alone. Conversely, no statistically significant differences were observed in the paw oedema test when the same PepC concentration was co-administered with dexamethasone at 3, 10 and 30 mg kg(-1) bw. PepC at 1000 mg kg(-1) bw did not cause any remarkable outcome in the hot-plate test. PepC appears to possess anti-inflammatory and peripheral antinociceptive activities, so it may be a candidate for nutraceutical ingredient. (C) 2013 Elsevier Ltd. All rights reserved.322156162FCT e via project NEW PROTECTION [PTDC/AGR-ALI/117658/2010][SFRH/BD/31604/2006]FCT e via project NEW PROTECTION [PTDC/AGR-ALI/117658/2010][SFRH/BD/31604/2006

Antiulcerogenic activity of peptide concentrates obtained from hydrolysis of whey proteins by proteases from Cynara cardunculus

Peptide concentrates generated by hydrolysis of whey with aqueous extracts of flowers of Cynara cardunculus were studied for possible protection of the stomach mucosa against ulcerative lesions caused by oral administration of absolute ethanol. Both the whole peptide fraction obtained via hydrolysis of whey protein concentrate (peptide concentrate, PepC) and its fraction below 3 kDa (PepCF) were able to reduce gastric injuries to significant levels (p < 0.05). Single-dose experiments, using 100 mg kg(-1) body weight (bw) of either PepCF or PepC, led to 68.5% and 37.4% protection, respectively - which compare well with 93.4% protection by 200 mg kg (1) bw carbenoxolone (a positive control). No dose-response correlation could be demonstrated. Gastric cytoprotection by PepCF appears to depend on sulphydryl-containing moieties, whereas PepC likely protects the gastric mucosa via the prostaglandin cycle and production of nitric oxide. (c) 2011 Published by Elsevier Ltd.2112934939CYTED[SFRH/BD/31604/2006][SFRH/BD/31604/2006

Ultrahigh-sensitivity temperature fiber sensor based on multimode interference

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)The proposed sensing device relies on the self-imaging effect that occurs in a pure silica multimode fiber (coreless MMF) section of a single-mode-multimode-single-mode (SMS)-based fiber structure. The influence of the coreless-MMF diameter on the external refractive index (RI) variation permitted the sensing head with the lowest MMF diameter (i.e., 55 mu m) to exhibit the maximum sensitivity (2800 nm/RIU). This approach also implied an ultrahigh sensitivity of this fiber device to temperature variations in the liquid RI of 1.43: a maximum sensitivity of -1880 pm/degrees C was indeed attained. Therefore, the results produced were over 100-fold those of the typical value of approximately 13 pm/degrees C achieved in air using a similar device. Numerical analysis of an evanescent wave absorption sensor was performed, in order to extend the range of liquids with a detectable RI to above 1.43. The suggested model is an SMS fiber device where a polymer coating, with an RI as low as 1.3, is deposited over the coreless MMF; numerical results are presented pertaining to several polymer thicknesses in terms of external RI variation. (C) 2012 Optical Society of America511632363242Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Financiadora de Estudos e Projetos (FINEP)MICRO-PHYTE [PTDC/EBB-EBI/102728/2008]European Union (EU) [SFRH/BD/47799/2008]Portuguese Stateproject COST [299]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPES [293/11]CAPES [23038.029912/2008-05]MICRO-PHYTE [PTDC/EBB-EBI/102728/2008]European Union (EU) [SFRH/BD/47799/2008]project COST [299