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An elegant synthesis of 2-aroylfuro[3,2-c]quinolines 2a–e from quinolone-based chalcones 1a–evia bromination of the exocyclic double bond followed by furan ring formation was developed. Interestingly, during bromination the tautomerization of the quinolin-4(1H)-one ring of compounds 1a–e into the corresponding 4-hydroxyquinoline occurred followed by cyclization to give in a one-pot transformation, upon in situ oxidation, the 2-aroylfuro[3,2-c]quinolines 2a–e. In the bromination of the quinolone-based chalcone 1e, bearing a hydroxy group at the ortho-position of the aryl ring, two compounds were obtained; the major one was the expected 2-aroylfuro[3,2-c]quinoline 2e dibrominated in the aryl ring, due to the activating effect of the hydroxy group, and the minor was identified as 12a-bromo-6b,12a-dihydro-12H-chromeno[2′,3′:4,5]furo[3,2-c]quinolin-12-one 3. Two possible mechanistic pathways were proposed to explain the formation of compound 3. The structures of all new compounds were confirmed by 1H and 13C NMR, ESI and HRMS spectra. Compounds 2a–e and 3 showed no significant scavenging activity towards the free radicals ABTS+˙ and NO˙, but compounds 2a and 2c showed promising activity as acetylcholinesterase inhibitors (IC50 = 78.99 ± 2.75 μM and 27.52 ± 0.23 μM, respectively). [ABSTRACT FROM AUTHOR]

Nine Tunisian Thymus capitatus (L.) Hoff. et Link. populations harvested in six bioclimatic zones extending from the sub humid (550 mm rainfall/year) to the lower arid (96.3 mm rainfall/year), and grown at altitudes ranging from 60 to 600 m were assessed for their phenolic composition. The identification of phenolic compounds was revealed by UHPLC-DAD-ESI/MS n . 11 phenolic compounds including three phenolic acids (rosmarinic acid, salvianolic acid A, salvianolic acid E), three flavanones (hesperidin, eriodictyol and naringenin), two C-glycoside isomers of the flavone apigenin, one flavanol gallocatechine, one flavanonol taxifolin and one phenolic monoterpen (carvacrol) were identified. Differences in phenolic composition among populations, in relationship with altitudes and/or annual rainfall were shown. Higher amounts of total phenols, total flavonoids, rosmarinic acid and carvacrol were detected in samples from the most arid zones (96.3–167 mm rainfall/year) in comparison with populations located in wet lands (450–660 mm rainfall/year). The altitude within or between contiguous climates is a main factor influencing phenol compounds content. The chemical variation among the populations should lead to the selection of plants with high potential in order to use them in health care and food industry. [ABSTRACT FROM AUTHOR]

Wine polymeric material (WPM), which includes polysaccharides, proteins, and polyphenolic compounds, interacts with anthocyanins. To determine the contribution of polysaccharides in these interactions, the diffusion performance of anthocyanins along a dialysis membrane was determined in the presence and absence of isolated mannoproteins (MP) and arabinogalactans (AG) from WPM. Furthermore, to estimate the extent of the interaction between WPM and polyphenolic compounds, the activation energy (E a ) required for their diffusion in the presence of WPM was determined. AG, generally more abundant than MP in wine, interact in a greater extent with anthocyanins, showing their relevant contribution for WPM/anthocyanins interactions. The E a for the diffusion of polyphenolic compounds in presence of WPM indicated the occurrence of interactions with relative weak to strong intensities (2.6–50.8 kJ/mol). As not all polyphenolic compounds were able to be released from WPM, stronger interactions, possibly by covalent linkages, are involved, providing new insights on WPM/polyphenolic compounds relationships. [ABSTRACT FROM AUTHOR]

Huntington's disease (HD) is a polyglutamine-expansion neurodegenerative disorder caused by increased number of CAG repeats in the HTT gene, encoding for the huntingtin protein. The mutation is linked to several intracellular mechanisms, including oxidative stress. Flavones are compounds with a protective role in neurodegenerative pathologies. In the present study we analyzed the protective effect of luteolin (Lut, 3′,4′,5,7-tetrahydroxyflavone) and four luteolin derivatives bearing 3-alkyl chains of 1, 4, 6 and 10 carbons (Lut-C1, Lut-C4, Lut-C6, Lut-C10) in striatal cells derived from HD knock-in mice expressing mutant Htt (ST Hdh Q111/Q111 ) versus wild-type striatal cells (ST Hdh Q7/Q7 ). HD cells showed increased caspase-3-like activity and intracellular reactive oxygen species (ROS), which were significantly decreased following treatment with Lut-C4 and Lut-C6 under concentrations that enhanced cell viability. Interestingly, Lut-C4 and Lut-C6 rose the nuclear levels of phospho(Ser40)-nuclear factor (erythroid-derived-2)-like 2 (Nrf2) and Nrf2/ARE transcriptional activity. Concordantly with increased Nrf2/ARE transcription, Lut-C6 enhanced superoxide dismutase 1 (SOD1) mRNA and SOD activity and glutamate-cysteine ligase catalytic subunit (GCLc) mRNA and protein levels, while Lut-C4 induced mRNA levels of GCLc only in mutant striatal cells. Data suggest that Lut-C6 luteolin derivative (in particular) might be relevant for the development of antioxidant strategies in HD. [ABSTRACT FROM AUTHOR]

Propolis is a natural product produced by bees that contains a complex mixture of compounds, including phenolic compounds and flavonoids. These compounds contribute to its biological activities, such as antioxidant capacity. This study analysed the pollen profile, total phenolic content (TPC), antioxidant properties, and phenolic compound profile of four propolis samples from Portugal. The total phenolic compounds in the samples were determined by six different techniques: four different Folin–Ciocalteu (F-C) methods, spectrophotometry (SPECT), and voltammetry (SWV). Of the six methods, SPECT allowed the highest quantification, while SWV achieved the lowest. The mean TPC values for these methods were 422 ± 98 and 47 ± 11 mg GAE/g sample, respectively. Antioxidant capacity was determined by four different methods: DPPH, FRAP, original ferrocyanide (OFec), and modified ferrocyanide (MFec). The MFec method gave the highest antioxidant capacity for all samples, followed by the DPPH method. The study also investigated the correlation between TPC and antioxidant capacity with the presence of hydroxybenzoic acid (HBA), hydroxycinnamic acid (HCA), and flavonoids (FLAV) in propolis samples. The results showed that the concentrations of specific compounds in propolis samples can significantly impact their antioxidant capacity and TPC quantification. Analysis of the profile of phenolic compounds by the UHPLC-DAD-ESI-MS technique identified chrysin, caffeic acid isoprenyl ester, pinocembrin, galangin, pinobanksin-3-O-acetate, and caffeic acid phenyl ester as the major compounds in the four propolis samples. In conclusion, this study shows the importance of the choice of method for determining TPC and antioxidant activity in samples and the contribution of HBA and HCA content to their quantification. [ABSTRACT FROM AUTHOR]

Abstract: Olive mill wastewaters (OMW) are a potential source of biophenols, but they have a complex composition with many unknown phenolics. The analysis of purified methanol extracts from two Portuguese OMW by electrospray mass spectrometry in the negative mode showed [M−H]− ions at m/z 539 and m/z 523, corresponding respectively to oleuropein and ligstroside isomers which contain the glucose unit linked to its aromatic moiety. Also, the fragmentation pathway of the [M−H]− ions at m/z 863, 685 and 847 indicated the presence of a diglucoside derivative of the oleuropein isomer and of mono- and diglucosides of the ligstroside isomer, respectively. Moreover, the two OMW samples contained an elenoic derivative of the ion at m/z 685 and a degradation product (m/z 453) of the [M−H]− ion at m/z 523. Future studies focusing on the abundance of these compounds on OMW, as well as their bioactivities, will determine their possible industrial exploitation. [Copyright &y& Elsevier]

Abstract: The present work describes the protective effects of the crude Northeast Portuguese propolis enriched phenolic extract against staurosporine (STS) and hydrogen peroxide (H2O2)-induced neurotoxicity. These two stress inducers act through various pathways, including the production of reactive oxygen species (ROS) and the induction of apoptosis through caspases activation. STS (25 and 50nM) and H2O2 (100μM) increased intracellular ROS and diminished cellular reducing ability in cultured cortical neurons, under conditions unrelated with massive loss of plasma membrane integrity, suggesting decreased neuronal function. Moreover, 25nM STS and 100μM H2O2 increased caspase-3 activity by about 2.8- and 4.6-fold, respectively. Pre-treatment of cortical neurons with the ethanolic extract of propolis (EEP) in the range of 0.01–1μg/ml showed no protective effect on cell reducing capacity, but decreased H2O2-stimulated increment in ROS production by about 17%. In addition, the EEP attenuated STS- or H2O2-induced activation of caspase-3 by 23–39%. Overall, the results show moderate protective effects induced by Northeast Portuguese EEP in cortical neurons subjected to stress stimuli. [Copyright &y& Elsevier]

Abstract: Fourier transform infrared (FTIR) spectroscopy has being emphasised as a widespread technique in the quick assess of food components. In this work, procyanidins were extracted with methanol and acetone/water from the seeds of white and red grape varieties. A fractionation by graded methanol/chloroform precipitations allowed to obtain 26 samples that were characterised using thiolysis as pre-treatment followed by HPLC-UV and MS detection. The average degree of polymerisation (DPn) of the procyanidins in the samples ranged from 2 to 11 flavan-3-ol residues. FTIR spectroscopy within the wavenumbers region of 1800–700cm−1 allowed to build a partial least squares (PLS1) regression model with 8 latent variables (LVs) for the estimation of the DPn, giving a RMSECV of 11.7%, with a R 2 of 0.91 and a RMSEP of 2.58. The application of orthogonal projection to latent structures (O-PLS1) clarifies the interpretation of the regression model vectors. Moreover, the O-PLS procedure has removed 88% of non-correlated variations with the DPn, allowing to relate the increase of the absorbance peaks at 1203 and 1099cm−1 with the increase of the DPn due to the higher proportion of substitutions in the aromatic ring of the polymerised procyanidin molecules. [Copyright &y& Elsevier]

Abstract: Black olives of Taggiasca (Ta) and Conservolea (Co) varieties were processed according to the Greek style method in order to investigate the effect of this type of table olive processing on cell wall composition. Naturally black processing involves the storage in brine of fully ripe olives for several months, allowing a spontaneous fermentation by a mixed flora followed by fermentation by the lactic acid bacteria and yeasts. The smaller fruits of Ta variety are richer in pectic polysaccharides, accounting for half of total cell wall polysaccharides (12mg/fruit), whereas in Co they accounted for one third (23mg/fruit). Fresh Co olives had higher proportion of glucuronoxylans and xyloglucans (33%), whereas these polysaccharides accounted for 22% in Ta. The processing did not cause significant variations in the cell wall polysaccharide composition of Ta fruits, although pectic polysaccharides became more soluble in aqueous solutions. Conversely, processed Co olives had slightly higher amounts of galacturonan-rich pectic polysaccharides than the unprocessed fruits, suggesting that the long stage in brine might have contributed to the stabilisation and/or the biosynthesis of new polysaccharides. The changes caused by processing on cell wall polysaccharides appear to be closely related to the activity and availability of cell wall degrading enzymes. [Copyright &y& Elsevier]

The preparation of table olives according to the Italian traditional “Ferrandina” method (Fer) includes an initial blanching step of black Cassanese olives, followed by salting and oven-drying. Its industrial implementation, also called the “Sybaris” method (Syb), replaces the blanching procedure by cutting the olives followed by immersion in water. The measurement of tensile properties showed that the Fer processing increased the weakness, softness, and deformability of the skin and the flesh of olive fruits, while the flesh of the Syb fruits became stronger and stiffer. These differences are probably correlated to the degradation and/or reorganisation of cell wall polysaccharides in the fruits. The degradation of pectic and hemicellulosic polysaccharides in the Fer olives was inferred by their increased solubility in aqueous solutions. Contrarily, retention of pectic polysaccharides was observed in Syb olives. As no correlation was found between cell wall degrading enzymatic activities and cell wall polysaccharides extractability, it is probable that these modifications were driven by heat. [ABSTRACT FROM AUTHOR]

Abstract: In this work, procyanidins were extracted with methanol from the seeds of white and red grape varieties, and fractionated using graded methanol/chloroform precipitation in order to obtain the oligomers of lower molecular weight. These were analyzed by electrospray ionization-mass spectrometry (ESI-MS and ESI-MS/MS) in the positive mode. Protonated molecules, [M+H]+, of procyanidin species of nongalloylated and monogalloylated type-A and type-B oligomers, with degree of polymerisation 2–5, and digalloylated oligomers, with degree of polymerisation 2–3, were observed in the ESI-MS spectra. Type-A procyanidin abundance accounted for 60–80% of the abundance of the corresponding type-B species. Independent of the interflavanic linkage, the abundance of monogalloylated dimers accounted for 20% of the abundance of the corresponding nongalloylated ones. For the higher degrees of polymerisation, the abundance of galloylated oligomers was shown to reach up to 60% of the abundance of the corresponding nongalloylated oligomers. Thiolytic analyses showed that the type-A interflavanic linkages were present in the terminal units whereas the type-B interflavanic linkages were present as extension units. Although many reports are already available regarding the analyses of procyanidin polymers and grape seed procyanidins, this is the first report for the occurrence of type-A galloylated procyanidins. The similarity of the relative abundances and structural features observed in the samples of both white and red grape varieties, shows that these are characteristic of grape seeds. [Copyright &y& Elsevier]

Abstract: The structure of the arabinan moiety of a purified arabinan-rich pectic polysaccharide from the cell walls of Prunus dulcis seeds was investigated by NMR spectroscopy. This polymer, which is able to induce a lymphocyte stimulatory effect, had an arabinan glycosidic-linkage composed of T-Araf: (1→5)-Araf: (1→3,5)-Araf: (1→2,3,5)-Araf in the relative proportions of approximately 3:2:1:1. Based on the 1H, 13C, COSYPR, gHSQC and gHMBC spectra of analysed arabinan, a tentative structure is presented, showing that it is composed by a very branched and, possibly, repetitive structure of seven residues. The observed (1→5) direct linkage between (1→2,3,5)-Araf and (1→3,5)-Araf residues support the occurrence of these contiguous branched residues in the arabinan backbone. [Copyright &y& Elsevier]

Small deformation dynamic rheometry was used to characterise the calcium-induced gelation of low-methoxyl pectins, at two different pH values. The gelation kinetics was interpreted with basis on the change of the storage modulus with time, taken as a measure of changes in cross-linking density within the pectin–calcium network. The temperature influence on the rate of gel formation and ageing was evaluated, as well as the temperature sensitivity of the cured gels. The formation and the softening/melting of pectin–calcium networks were also studied under non-isothermal conditions. The structural diversity of the two pectin samples had a great influence on the gelation kinetics and thermal behaviour of these pectin–calcium networks, due to differences in the steric arrangement or environment and/or availability of the chelating groups. An association mechanism is suggested to predominate under conditions of low availability of dissociated carboxylic groups, due to a low pH, higher degree of methylation, or steric constraints introduced by acetylation or neutral side chains, different from the classical ‘egg-box’ model, and where non-ionic hydrogen bonding and hydrophobic interactions may co-exist and cooperate with coordinative binding of calcium-ions. [Copyright &y& Elsevier]

Pectic raw material was extracted from the alcohol insoluble residue of olive pomace. After purification, the olive pectic extract (OPE) contained 48% of galacturonic acid (GalA) and 31% of arabinose, in a total sugar content of 72%, and a degree of methylesterification (DM) of 43%. Phase diagrams were established to define the physical state of the OPE/calcium systems, at pH 3 and 7, as a function of GalA and calcium concentration. The rheological properties of the OPE/calcium systems were investigated by small-amplitude oscillatory tests. Kinetics of gel ageing and the viscoelastic properties of the cured gels were evaluated as a function of GalA and calcium concentration at pH 3 and 7. Compared with the observed behaviour of a citrus pectin, taken as representative of a commercial low-methoxyl pectin, the OPE showed higher critical GalA and calcium concentrations for gelation to occur, a larger region corresponding to homogeneous gel, and gels characterised by lower viscoelastic moduli, at similar GalA and calcium concentrations. [Copyright &y& Elsevier]

An arabinan (97% of Ara and 3% of hexuronic acid) was isolated from the alcohol-insoluble residue (AIR) of olive pomace by treatment with 0.02 M HNO3, at 80 °C, followed by graded precipitation with ethanol. It was separated from acidic pectic polysaccharides by anion-exchange chromatography, and by size-exclusion chromatography its molecular weight was estimated as 8.4 kDa. By methylation analysis, the linkage composition was established as 5:4:3:1 for (1→5)-Araf, T-Araf, (1→3,5)-Araf and (1→3)-Araf, respectively. 13C NMR spectroscopy confirmed this linkage composition, and allowed to assign the α anomeric configuration for the arabinofuranosyl residues, except for some terminally linked ones, that were seen to occur as T-β-Araf. By 2D NMR spectroscopy (1H and 13C), it was possible to conclude that the T-β-Araf was (1→5)-linked to a (1→5)-Araf residue. Also, in the arabinan (1→5)-Araf backbone, the branched (1→3,5)-Araf residues were always adjacent to linear (1→5)-Araf residues. A tentative structure is proposed. [Copyright &y& Elsevier]

The search for new natural antioxidants is a growing area of research due to the broad spectrum of their biological properties, which are associated with the prevention of chronic diseases that originate in oxidative stress. Among the published works, phenolic compounds or derivatives were spotlit because of their antioxidant abilities, albeit other potential bioactivities such as cytoprotective, antiproliferative and cytotoxic ones were also investigated. The application of natural compounds as ingredients in novel products to emphasize specific characteristics or new strategies to improve the quality and antioxidant properties of health-promoting natural products/bioactive compounds were also addressed by some contributing authors. 10.3390/molecules23092356 28 Wu P.-S., Li Y.-S., Kuo Y.-C., Tsai S.-J.J., Lin C.C. Preparation and evaluation of novel transfersomes combined with the natural antioxidant resveratrol. [Extracted from the article]

The article presents an editorial which offers information on several aspects associated with an antioxidant and related bioactive properties of natural products, comprising structure–bioactivity correlations, mechanisms of action, the search of new sources of antioxidants, and the impact of botanical, geographical, and processing factors on the levels of these compounds. It includes an analysis of phenolic compounds.

In this study, the anti-cancer, anti-tyrosinase, and antioxidant activities of essential oils (EOs) of berries and leaves of Juniperus phoenicea grown wild in North of Tunisia were investigated. The EO yields from leaves and berries were 1.69% and 0.45%, respectively. GC-MS analysis revealed that α-pinene is the predominant component in both EOs (44.17 and 83.56%, respectively). Leaves essential oil presented high levels of β-phellandrene (18%) and camphene (15%). The EOs displayed cytotoxic effects against MCF-7 breast cancer cell, HT-29 colon cancer, and the normal cells H9C2 cardiomyoblasts. Leaves oil strongly inhibited colon cell line proliferation (IC50 of 38 µg/mL), while berries essential oil was more potent against breast cancerous cells MCF-7 (IC50 of 60 µg/mL). Interestingly, berries essential oil exhibited high ability to inhibit melanin synthesis by inhibiting enzyme mono and diphenolase activities. Overall, the results suggested that the two oils are significant sources of healthy natural chemicals. [ABSTRACT FROM AUTHOR]

In the present study, norlobaridone (NBD) was isolated from Parmotrema and then evaluated as a new potent quorum sensing (QS) inhibitor against Pseudomonas aeruginosa biofilm development. This phenolic natural product was found to reduce P. aeruginosa biofilm formation (64.6% inhibition) and its related virulence factors, such as pyocyanin and rhamnolipids (% inhibition = 61.1% and 55%, respectively). In vitro assays inhibitory effects against a number of known LuxR-type receptors revealed that NBD was able to specifically block P. aeruginosa's LasR in a dose-dependent manner. Further molecular studies (e.g., sedimentation velocity and thermal shift assays) demonstrated that NBD destabilized LasR upon binding and damaged its functional quaternary structure (i.e., the functional dimeric form). The use of modelling and molecular dynamics (MD) simulations also allowed us to further understand its interaction with LasR, and how this can disrupt its dimeric form. Finally, our findings show that NBD is a powerful and specific LasR antagonist that should be widely employed as a chemical probe in QS of P. aeruginosa, providing new insights into LasR antagonism processes. The new discoveries shed light on the mysterious world of LuxR-type QS in this key opportunistic pathogen. [ABSTRACT FROM AUTHOR]

The antioxidant activity of bee pollen (mainly composed by Cistus ladanifer pellets) was explored in the context of black pudding production. For this purpose, three black pudding formulations comprising varying antioxidant compounds (sodium ascorbate, bee pollen and bee pollen extract) were produced. Bee pollen was characterized according to the botanical origin, antioxidant activity, total phenol and flavonoid contents and phenolic profile. Black pudding was characterized by the microbiological safety, lipid oxidation, pH, water activity and humidity at 1, 10, 21, 30 and 37 days. Sensory acceptance was evaluated on the four first periods of storage. Salmonella spp., Escherichia coli and Listeria monocytogenes were absent in all samples. Small variations on humidity and pH were observed during the black pudding's storage. Regarding lipid oxidation, it increased, on average, from 1.36 mg to 2.11 mg malondialdehyde/kg meat. Differences among the three formulations were only significant on the first days of storage. The sensory assessment did not differ between products. This study suggests that bee pollen may be used as a natural antioxidant in meat products, yet a careful labelling is essential to alert allergic consumers. • Bee pollen is a healthy product. • Chemical and sensory characterization of Black pudding with pollen. • The work suggest that bee pollen could be a natural alternative to prevent the lipid oxidation in black pudding. [ABSTRACT FROM AUTHOR]

Abstract Natural products, like propolis, have been subject of interest by several industries mainly due to their biological activities. However, besides being produced in low amounts propolis has a great variability in terms of chemical composition and bioactivities' profiles, constituting a problem for the development of propolis-based products and for its acceptance by the medical community. The aim of this work relates to the study of the bioactivities, in particular the antioxidant and the antimicrobial properties, as well as the chemical characterization of Portuguese propolis samples collected in an apiary sited at Gerês (G) along four consecutive years. Ethanol extracts of the four propolis samples (G.EEs) display antimicrobial activity, especially against Gram-positive spore forming bacteria. Antioxidant activity, evaluated by three different in vitro assays, was confirmed in vivo by flow cytometry using Saccharomyces cerevisiae as eukaryotic cell model. Cells incubated with G.EEs prior to H 2 O 2 incubation, or incubated with G.EEs and H 2 O 2 simultaneously, display higher viability than cells incubated only with H 2 O 2 , suggesting that G.EEs protect yeast cells against induced oxidative stress. All tested propolis samples exhibit very similar antimicrobial and antioxidant activities. Chemical analysis of G.EEs revealed no significant differences in terms of phenolic profiles, namely in the compounds to which propolis bioactivities are ascribed, thus supporting the more constant behavior evidenced by these propolis samples. This work highlights the valuable properties of this bee product and reveals a constancy of bioactivities in a Portuguese propolis sample over four years, raising awareness to the potentialities of this natural product often regarded as a beekeeping waste. Graphical abstract Unlabelled Image Highlights • Antibacterial activity is shown by all four propolis samples. • Specific spectrum of action was found against gram-positive spore forming bacteria. • All propolis samples show good antioxidant activity both in vitro and in vivo. • Propolis samples exhibit similar biological activities over four years. • Similarities in chemical profiles confirm the constancy of bioactivities. [ABSTRACT FROM AUTHOR]

The present study assessed two different plant parts (leaves and tubers) of Arum italicum species growing in Northeast Algeria for their phytochemical composition and pharmacological effects. The phytochemical content was determined using ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DADESI/MS). The results revealed that the tuber extract was rich in lignans with a fraxiresinol glycoside as the major compound. In contrast, the leaf extract was rich in flavonoid glycosides, described for the first time in the aerial part of this species. The extract’s inhibitory activity against key enzymes was linked to hyperglycemia, α-glucosidase, and α-amylase, and their ability to inhibit the growth of human gastric carcinoma (AGS) and lung carcinoma (A549) cancer cell lines was also assessed. A cell line morphology study was also conducted with the most effective extract. The chromatin status of the cells was evaluated using DAPI, while the cytoplasmic morphology was evaluated using phalloidin. The tuber extract generally inhibited α-glucosidase and α-amylase enzymes more efficiently than the leaf extract. Its inhibition effect against the α-glucosidase was significantly higher when compared to the standard acarbose. The tuber extract also caused more viability loss of AGS and A549 cancer cells than the leaf extract in the cytotoxicity assay. In conclusion, our findings show that, compared to the leaf extract, the tuber extract exhibited more pronounced biological effects. The strong inhibitory potential of the tuber extract against the α-glucosidase enzyme should also be highlighted, which suggests it is a good candidate for discovering new antidiabetic agents. [ABSTRACT FROM AUTHOR]

Cannabis sativa is a multipurpose plant that has been used in medicine for centuries. Recently, considerable research has focused on the bioactive compounds of this plant, particularly cannabinoids and terpenes. Among other properties, these compounds exhibit antitumor effects in several cancer types, including colorectal cancer (CRC). Cannabinoids show positive effects in the treatment of CRC by inducing apoptosis, proliferation, metastasis, inflammation, angiogenesis, oxidative stress, and autophagy. Terpenes, such as β-caryophyllene, limonene, and myrcene, have also been reported to have potential antitumor effects on CRC through the induction of apoptosis, the inhibition of cell proliferation, and angiogenesis. In addition, synergy effects between cannabinoids and terpenes are believed to be important factors in the treatment of CRC. This review focuses on the current knowledge about the potential of cannabinoids and terpenoids from C. sativa to serve as bioactive agents for the treatment of CRC while evidencing the need for further research to fully elucidate the mechanisms of action and the safety of these compounds. [ABSTRACT FROM AUTHOR]

Phototrophic organisms, such as microalgae and cyanobacteria, are known to be major contributors to stone decay. The purpose of this study was to assess the dolomitic limestone colonization by phototrophic organisms, using single vs artificial multispecies, under laboratory conditions. To achieve this aim, dolomitic limestone blocks were inoculated with single phototrophic species previously collected from the Old Cathedral of Coimbra, for a period of three months. In parallel, limestone blocks were also inoculated with a mixture of the same isolated single species, in order to compare the colonization capacities of both conditions. Results were evaluated based on visual inspection, surface covered area, colorimetric and SEM analyses. Results showed that the phototrophic organisms were able to colonize the dolomitic limestone blocks in both conditions (single vs artificial multispecies), but biofilm development was more enhanced when single species, rather than multispecies, were used. The obtained results also allowed to observe the capacity for endolithic colonization and the formation of small cavities by some species. [ABSTRACT FROM AUTHOR]

Broccoli by-products from frozen-food industry account for 45% of the initial broccoli heads. They consist on stalks, inflorescences, and leaves, blanched and non-blanched, sharing the nutritional value and bioactive compounds of commercial broccoli heads. However, their high perishability prevents further valorisation. Therefore, in this study microwave hydrodiffusion and gravity (MHG) technology was used to dehydrate broccoli by-products and simultaneously recover the water-soluble diffused compounds for food ingredients use. The hydrodiffusion allowed to obtain a dried material with 12% moisture in 43 min when 550 g of broccoli by-products were used, preserving polysaccharides and proteins. Diffused water contained up to 317 µg/mL gallic acid equivalents of phenolic compounds, 11 mg/mL free sugars, 9 mg/mL amino acids, and 356 µg/mL glucosinolates, depending on the type of by-product used. These results show the potential of MHG technology for valorisation of broccoli by-products by its simultaneous stabilization by dehydration and extraction of bioactive compounds. [ABSTRACT FROM AUTHOR]

Thymus herba-barona, Thymus pseudolanuginosus, and Thymus caespititius decoctions were screened for their phenolic constituents, along with their potential antioxidant, anti-inflammatory, and antibacterial activities. The total phenolic compounds in the extracts of the three plants ranged from 236.0 ± 26.6 mgGAE/g (T. caespititus) to 293.0 ± 30.5 mgGAE/g of extract (T. pseudolanuginosus), being particularly rich in caffeic acid derivatives, namely rosmarinic acid and its structural isomers, as well as flavones, such as luteolin-O-glucuronide. The T. pseudolanuginosus extract presented the best DPPH radical scavenging ability (EC50 = 10.9 ± 0.7 μg/mL), a high reducing power (EC50 = 32.2 ± 8.2 μg/mL), and effectively inhibited the oxidation of β-carotene (EC50 = 2.4 ± 0.2 μg/mL). The extracts also showed NO• scavenging activity close to that of ascorbic acid, and thus might be useful as anti-inflammatory agents. In addition, they exhibited antibacterial activity against gram-negative and gram-positive bacteria. Staphylococcus aureus strains were the most sensitive bacteria to thyme extracts, with minimum inhibitory concentration and minimum bactericidal concentration values in the range of 0.6-3.5 mg/mL. Overall, this work is an important contribution for the phytochemical characterization and the potential antioxidant, anti-inflammatory, and antimicrobial activities of these three Thymus species, which have been poorly explored. [ABSTRACT FROM AUTHOR]

Simple Summary: This study assessed a humane endpoint scoring system to detect animal suffering in a rat model of type 2 diabetes. Sprague-Dawley male rats were divided into control and induced (fructose-fed and streptozotocin (STZ) administration) groups. Induced animals drank 10% fructose for 14 days, then received STZ (40 mg/kg) intraperitoneally. Weekly monitoring of body weight, water, and food consumption, 14 parameters of animal welfare, and blood glucose levels were conducted. Results showed weight loss, polyuria, polyphagia, and polydipsia, as well as lack of grooming, narrowing of the orbital area, curved posture, liquid/pasty diarrhea, and abdominal distension. The most useful parameters to evaluate humane endpoints in this type 2 diabetes rat induction model were dehydration, absence of grooming, the posture of the animals, abdominal visualization and palpation, and fecal appearance. The glycemia was significantly higher in the induced group, validating the animal model of diabetes. The humane endpoints table was suitable for monitoring animal welfare. This work aimed to define a humane endpoint scoring system able to objectively identify signs of animal suffering in a rat model of type 2 diabetes. Sprague-Dawley male rats were divided into control and induced group. The induced animals drink a 10% fructose solution for 14 days. Then, received an administration of streptozotocin (40 mg/kg). Animals' body weight, water and food consumption were recorded weekly. To evaluate animal welfare, a score sheet with 14 parameters was employed. Blood glucose levels were measured at three time points. After seven weeks of initiating the protocol, the rats were euthanized. The induced animals showed weight loss, polyuria, polyphagia, and polydipsia. According to our humane endpoints table, changes in animal welfare became noticeable after the STZ administration. None of the animals hit the critical score limit (four). Data showed that the most effective parameters to assess welfare in this type 2 diabetes rat induction model were dehydration, grooming, posture, abdominal visualization, and stool appearance. The glycemia was significantly higher in the induced group when compared to the controls (p < 0.01). Induced animals' murinometric and nutritional parameters were significantly lower than the controls (p < 0.01). Our findings suggest that in this rat model of type 2 diabetes with STZ-induced following fructose consumption, our list of humane endpoints is suitable for monitoring the animals' welfare. [ABSTRACT FROM AUTHOR]

Melanoma is the deadliest type of skin cancer, with about 61,000 deaths annually worldwide. Late diagnosis increases mortality rates due to melanoma's capacity to metastasise rapidly and patients' resistance to the available conventional therapies. Consequently, the interest in natural products as a strategy for drug discovery has been emerging. Propolis, a natural product produced by bees, has several biological properties, including anticancer effects. Propolis from Gerês is one of the most studied Portuguese propolis. Our group has previously demonstrated that an ethanol extract of Gerês propolis collected in 2018 (G18.EE) and its fractions (n-hexane, ethyl acetate, and n-butanol) decrease melanoma cell viability. Out of all the fractions, G18.EE-n-BuOH showed the highest potential as a melanoma pharmacological therapy. Thus, in this work, G18.EE-n-BuOH was fractioned into 17 subfractions whose effect was evaluated in A375 BRAF-mutated melanoma cells. The subfractions with the highest cytotoxic activity were analysed by UPLC-DAD-ESI/MSn in an attempt to understand which phenolic compounds could account for the anti-melanoma activity. The compounds identified are typical of the Gerês propolis, and some of them have already been linked with antitumor effectiveness. These results reaffirm that propolis compounds can be a source of new drugs and the isolation of compounds could allow its use in traditional medicine. [ABSTRACT FROM AUTHOR]

Fucaceae is the most dominant algae family along the intertidal areas of the Northern Hemisphere shorelines, being part of human customs for centuries with applications as a food source either for humans or animals, in agriculture and as remedies in folk medicine. These macroalgae are endowed with several phytochemicals of great industrial interest from which phlorotannins, a class of marine-exclusive polyphenols, have gathered much attention during the last few years due to their numerous possible therapeutic properties. These compounds are very abundant in brown seaweeds such as Fucaceae and have been demonstrated to possess numerous health-promoting properties, including antioxidant effects through scavenging of reactive oxygen species (ROS) or enhancement of intracellular antioxidant defenses, antidiabetic properties through their acarbose-like activity, stimulation of adipocytes glucose uptake and protection of β-pancreatic cells against high-glucose oxidative stress; anti-inflammatory effects through inhibition of several pro-inflammatory mediators; antitumor properties by activation of apoptosis on cancerous cells and metastasis inhibition, among others. These multiple health properties render phlorotannins great potential for application in numerous therapeutical approaches. This review addresses the major contribution of phlototannins for the biological effects that have been described for seaweeds from Fucaceae. In addition, the bioavailability of this group of phenolic compounds is discussed. [ABSTRACT FROM AUTHOR]

Dicoumarol, a coumarin-like compound, is known for its anticoagulant properties associated with the ability to inhibit vitamin K, being prescribed as a drug for several decades. The pharmaceutical value of dicoumarol turned it into a focus of chemists' attention, aiming its synthesis and of dicoumarol derivatives, bringing to light new methodologies. In recent years, several other bioactive effects have been claimed for dicoumarol and its derivatives, including anti-inflammatory, antimicrobial, antifungal, and anticancer, although the mechanisms of action underlying them are mostly not disclosed and additional research is needed to unravel them. This review presents a state of the art on the chemistry of dicoumarols, and their potential anticancer characteristics, highlighting the mechanisms of action elucidated so far. In parallel, we draw attention to the lack of in vivo studies and clinical trials to assess the safety and efficacy as drugs for later application. [ABSTRACT FROM AUTHOR]

In the present study, two extracts from the aerial parts of the endemic species Satureja hispidula were analyzed for the first time by ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MS) method in order to identify and quantify their phenolic compounds. These extracts' antioxidant, α-glucosidase and α-amylase inhibitory activities were also evaluated. UHPLC-DAD-ESI/MS allowed the identification of 28 and 20 compounds in the ethanolic and aqueous extracts, respectively; among them, 5-O-caffeoylquinic acid was the most abundant in both extracts. The biological assay results indicate that the species S. hispidula, besides its high antioxidant power, is also potentially useful for inhibiting the α-glucosidase enzyme. In both antioxidant and α-glucosidase inhibitory assays, the aqueous extract exhibited the most promising results, significantly better than the standards used as positive controls. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a poor-prognosis type of cancer with high resistance to chemotherapy, making the search for safe drugs a mandatory issue. Plant-derived products have potential to reduce negative side effects of cancer treatments. In this work, ability of a defatted methanolic extract of Alocasia gigantea leaves to fight HCC was evaluated in an animal model. Overall, treatment of HCC-induced mice with the methanolic extract at 150 mg/kg body weight for four consecutive weeks caused induction of autophagy through silencing of the relative expression of autophagy suppressor (mTOR) and inducement of autophagy markers (AMPK, Beclin-1, and LC-3). Moreover, it improved preservation of the hepatic histological architecture of the animals, with minor hepatocytic changes but scattered foci of hepatocytic apoptosis. Chemical profiling of the methanolic extract via ultra-high-performance liquid chromatography coupled to a diode array detector and an electrospray mass spectrometer (UHPLC–DAD–ESI–MS/MS) allowed identification of di-C-glycosyl flavones, mostly represented by 6-C-hexosyl-8-C-pentosyl apigenin isomers, which may possibly be associated with inducement of the autophagy pathway in HCC. Overall, these outcomes gave an initial visualization of the operative effect of some compounds in A. gigantea leaves that are potential treatment for HCC. [ABSTRACT FROM AUTHOR]

Propolis, a natural product made by bees with resins and balsams, is known for its complex chemical composition and remarkable bioactivities. In this study, propolis extraction was studied seeking extracts with strong bioactivities using less orthodox solvents, with some derived from apiary products. For that, a propolis sample collected from Gerês apiary in 2018 (G18) was extracted by maceration with six different solvents: absolute ethanol, ethanol/water (7:3), honey brandy, mead, propylene glycol and water. The solvent influence on the chemical composition and antioxidant and antimicrobial activities of the extracts was investigated. Antioxidant potential was assessed by the DPPH free-radical-scavenging assay and the antimicrobial activity by the agar dilution method. Chemical composition of the extracts was determined in vitro by three colorimetric assays: total ortho-diphenols, phenolics and flavonoids contents and the LC-MS technique. To our knowledge, this is the first time that solvents such as honey brandy and mead have been studied. Honey brandy showed considerable potential to extract propolis active compounds able to inhibit the growth of bacteria such as the methicillin-sensitive Staphylococcus aureus and Propionibacterium acnes (MIC values of 100 and 200 µg/mL, respectively) and the fungi Candida albicans and Saccharomyces cerevisiae (MIC = 500 µg/mL, for both). Mead extracts displayed high antioxidant capacity (EC50 = 1.63 ± 0.27 µg/mL) and great activity against resistant bacteria such as the methicillin-resistant Staphylococcus aureus and Escherichia coli (MIC = 750 µg/mL, for both). The production of such solvents made from beehive products further promotes a diversification of apiary products and the exploration of new applications using eco-friendly solutions. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma is the most lethal cancer of the urological system due to late diagnosis and treatment resistance. Propolis, a beehive product, is a valuable natural source of compounds with bioactivities and may be a beneficial addition to current anticancer treatments. A Portuguese propolis sample, its fractions (n-hexane, ethyl acetate, n-butanol and water) and three subfractions (P1–P3), were tested for their toxicity on A498, 786-O and Caki-2 renal cell carcinoma cell lines and the non-neoplastic HK2 kidney cells. The ethyl acetate fraction showed the strongest toxicity against A498 (IC50 = 0.162 µg mL−1) and 786-O (IC50 = 0.271 µg mL−1) cells. With similar toxicity against 786-O, P1 (IC50 = 3.8 µg mL−1) and P3 (IC50 = 3.1 µg mL−1) exhibited greater effect when combined (IC50 = 2.5 µg mL−1). Results support the potential of propolis and its constituents as promising coadjuvants in renal cell carcinoma treatment. [ABSTRACT FROM AUTHOR]

Melanoma is the most aggressive and life-threatening skin cancer type. The melanoma genome is the most frequently mutated, with the BRAF mutation present in 40–60% of melanoma cases. BRAF-mutated melanomas are characterized by a higher aggressiveness and progression. Adjuvant targeted treatments, such as BRAF and MEK inhibitors, are added to surgical excision in BRAF-mutated metastatic melanomas to maximize treatment effectiveness. However, resistance remains the major therapeutic problem. Interest in natural products, like propolis, for therapeutic applications, has increased in the last years. Propolis healing proprieties offer great potential for the development of novel cancer drugs. As the activity of Portuguese propolis has never been studied in melanoma, we evaluated the antitumoral activity of propolis from Gerês (G18.EE) and its fractions (n-hexane, ethyl acetate (EtOAc), and n-butanol) in A375 and WM9 melanoma cell lines. Results from DPPH•/ABTS• radical scavenging assays indicated that the samples had relevant antioxidant activity, however, this was not confirmed in the cell models. G18.EE and its fractions decreased cell viability (SRB assay) and promoted ROS production (DHE/Mitotracker probes by flow cytometry), leading to activation of apoptotic signaling (expression of apoptosis markers). Our results suggest that the n-BuOH fraction has the potential to be explored in the pharmacological therapy of melanoma. [ABSTRACT FROM AUTHOR]

The Synechococcales is a large cyanobacterial order comprising both unicellular and filamentous forms, with parietal thylakoid arrangement. Previously, this order has been the subject of taxonomic revisions with new families being erected. During studies of the phototrophic communities on the limestone walls of the Old Cathedral of Coimbra (UNESCO monument), a coccoid Aphanocapsa‐like cyanobacterium was isolated. It was characterized using a polyphasic approach, based on morphology, 16S rRNA phylogenetic and phylogenomic analyses, internal transcribed spacer (ITS) secondary structure, and ecology. The 16S rRNA phylogenetic analyses showed that this strain is placed in a separate and highly supported family‐level clade, as part of a large group comprising the families Prochlorococcaceae and Prochlorotrichaceae, with Lagosinema as the closest (although quite distant) taxon. Additionally, the phylogenomic analysis also placed this strain in a separate lineage, situated distantly apart from the family Thermosynechococcaceae, but with strains assigned to Acaryochloris marina MBIC 11017 and Aphanocapsa montana BDHKU210001 as the closest taxa. Based on these data, as well as on the results from the secondary ITS structure, morphology, and ecology, we here propose the establishment of Petrachlorosaceae fam. nov., along with the description of Petrachloros gen. nov. and Petrachloros mirabilis sp. nov. We also address additional considerations regarding some cyanobacterial taxa within the order Synechococcales, which we believe deserve further revisions. [ABSTRACT FROM AUTHOR]

Abstract: Bioconversions using enzymes immobilized in magnetic supports present significant advantages due to the easy separation of the enzyme from the reaction mixture and the simplicity and low cost of the support preparation. The characterization of the oligosaccharide mixture obtained by the action of β-galactosidase covalently attached, via glutaraldehyde, to a hydrazide–Dacron–magnetite composite is presented. The fractionation of the oligosaccharide mixture by high performance liquid chromatography, followed by the analysis of the purified compounds by mass spectrometry and nuclear magnetic resonance spectroscopy permitted the identification of glucose, galactose, lactose and a hexose disaccharide containing a 1→6 linkage. Also, the following GOS were identified: β-d-Galp-(1→6)-β-d-Galp-(1→4)-Glcp, β-d-Galp-(1→4)-[β-d-Galp-(1→6)]-Glcp and β-d-Galp-(1→6)-β-d-Galp-(1→6)-β-d-Galp-(1→4)-Glcp. When GOS yield (26.2%) and kinetics of biotransformation of lactose by the Dacron immobilized β-galactosidase were compared with values obtained for the enzyme immobilized in other magnetic supports, similar behaviour was observed. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a chronic neurodegenerative disease and represents the major cause of dementia worldwide. Currently, there are no available treatments capable to deliver disease-modifying effects, and the available drugs can only alleviate the symptoms. The exact pathology of AD is not yet fully understood and several hallmarks such as the presence of amyloid-β (Aβ) senile plaques, neurofibrillary tangles (NFTs) as well as the loss of cholinergic function have been associated to AD. Distinct pharmacological targets have been validated to address AD, with acetylcholinesterase (AChE) and β-secretase-1 (BACE-1) being two of the most explored ones. A great deal of research has been devoted to the development of new AChE and BACE-1 effective inhibitors, tackled separately or in combination of both. The multi-factorial nature of AD conducted to the development of multi-target directed ligands (MTDLs), defined as single molecules capable to modulate more than one biological target, as an alternative approach to the old paradigm one-target one-drug. In this context, this review describes a collection of natural and synthetic compounds with dual-inhibitory properties towards both AChE and BACE-1 in the MTDLs context. Furthermore, this review also provides a critical comprehensive analysis of structure-activity relationships (SAR) of the synthetic compounds. [Display omitted] • AChE and BACE-1 are the most interesting AD related targets. • Single target AChE or BACE-1 inhibitors do not provide disease modifying effects. • Combining pharmacophores for AChE and BACE-1 inhibition results in well-balanced dual-inhibitors. • AChE and BACE-1 dual-inhibitors can be of both natural or synthetic origin. • BBB permeability should not be disregarded from the very beginning of any design strategy. [ABSTRACT FROM AUTHOR]

In a study that aimed to fingerprint the phototrophic community of the biodeteriorated walls of the Old Cathedral of Coimbra (UNESCO World Heritage Site), an unknown Nostoc/Komarekiella-like cyanobacterium was isolated. We employed a polyphasic approach based on morphological, ecological and phylogenetic analyses of the partial 16S and the whole 16S-23S ITS rRNA regions to characterize this organism. Our strains shared 16S rRNA gene sequence similarity of 99–100% with GenBank-assigned 'Nostoc sp.' sequences, and 98% similarity with the genera Goleter, Roholtiella, Aulosira and Komarekiella. Despite being morphologically similar to Komarekiella, phylogenetic analyses placed our strains in a separated genus-level clade, distant from Nostoc sensu stricto and with Komarekiella as the closest taxon. Considering all molecular, phylogenetic and ecological data, we here propose Parakomarekiella sesnandensis F.Soares, V.Ramos & A.Portugal, gen. et sp. nov. [ABSTRACT FROM AUTHOR]

The study describes the current state of knowledge on nanotechnology and its utilization in medicine. The focus in this manuscript was on the properties, usage safety, and potentially valuable applications of chitosan-based nanomaterials. Chitosan nanoparticles have high importance in nanomedicine, biomedical engineering, discovery and development of new drugs. The manuscript reviewed the new studies regarding the use of chitosan-based nanoparticles for creating new release systems with improved bioavailability, increased specificity and sensitivity, and reduced pharmacological toxicity of drugs. Nowadays, effective cancer treatment is a global problem, and recent advances in nanomedicine are of great importance. Special attention was put on the application of chitosan nanoparticles in developing new system for anticancer drug delivery. Pre-clinical and clinical studies support the use of chitosan-based nanoparticles in nanomedicine. This manuscript overviews the last progresses regarding the utilization, stability, and bioavailability of drug nanoencapsulation with chitosan and their safety. [ABSTRACT FROM AUTHOR]

• Flavan-3-ols were the main apple native polyphenols in apple pomace. • Hot water extraction reduced flavan-3-ols in 50%. • Oxidation products of polyphenols were part of the polyphenolic pool. • Non-extractable oxidized polyphenols were strongly attached to polysaccharides. Hot water is an easily implementable process for polyphenols extraction. To evaluate the effect of this process on apple pomace, the overall polyphenolic composition was assessed before and after hot water extraction, followed by extractions with aqueous/organic solutions. As determined by UHPLC-DAD, flavan-3-ols were the main apple native polyphenols. Their amount decreased 50% after hot water extraction, while the other classes remained unchanged. Dihydrochalcones and hydroxycinnamic acid oxidation products, were also observed, alongside with non-extractable oxidised procyanidins that represented more than 4-fold the amount of native apple polyphenols in the pomace. Microwave superheated-water extraction of the insoluble cell wall material in water/acetone solutions and the high amounts of polyphenols that were insoluble in water/ethanol solutions suggested that oxidised procyanidins could be covalently linked to polysaccharides. These complexes represented up to 40% of the available polyphenols from apple pomace, potentially relevant for agro-food waste valuation. [ABSTRACT FROM AUTHOR]

This study aimed to obtain a betalain-rich extract (BRE) from Opuntia ficus-indica peels and protect them through a holistic approach involving microencapsulation via spray-drying. To enhance the stability of the microencapsulated betalains, an antioxidant-rich extract (ARE) obtained through hydrothermal extraction from the residual material remaining after the conventional extraction of betalains was used as a stabilizer during the spray-drying process. The antioxidant activity of the ARE was evaluated by measuring its IC 50 value for 2,2-Diphenyl-1-picrylhydrazyl (DPPH) of 65.8 μg/mL, its Trolox equivalent antioxidant capacity (TEAC) of 60.4 g Trolox eq. /100 g, and its reducing power of 16.6 g butylated hydroxytoluene (BHT) eq./100 g. Spray-drying parameters were optimized using a Box-Behnken design to enhance the total betalain content and minimize by-product formation. The results demonstrated that the addition of the ARE significantly improved the stability of betalains during spray-drying, leading to the formation of microparticles with high betalain content and enhanced stability. The optimal conditions (0.72% starch, 1.50% BRE and 0.25% ARE) resulted in microparticles with a maximum concentration of 6.74 ± 0.09 mg Betalains /g. The predictive model exhibited high accuracy in estimating experimental values. This research provides a natural and sustainable solution for food coloring by effectively utilizing discarded Opuntia ficus-indica peel. Moreover, it offers new scientific understanding on the production of betalain-rich microparticles as a possible substitute for food coloring, with considerable benefits in terms of sustainability and high antioxidant capacity. • Holistic approach using O. ficus indica peels for stable, natural colorant. • Antioxidant-rich extract enhances betalain stability, yielding stable microparticles. • Box-Behnken design optimizes spray-drying, maximizing betalain concentration accurately. • Opuntia peels offers sustainable source for betalain-rich microparticles, reducing waste. • Microparticles as alternative for synthetic coloring, with high antioxidant capacity. [ABSTRACT FROM AUTHOR]

In 2013, UNESCO classified the 'University of Coimbra – Alta and Sofia ' (Portugal) as World Heritage site. Some of the limestone monuments that compose the site, such as the Old Cathedral of Coimbra, show clear visual effects of biological colonization by cyanobacteria and microalgae. The aim of this study was to thoroughly characterize the structural diversity of the photoautotrophic community at this site, combining isolation and molecular identification with next-generation sequencing techniques. Culture-dependent approaches resulted on the identification of green microalgae belonging to Prasiolales , Chlorellales , Watanabea , Chlamydomonadales and Sphaeropleales clades, and cyanobacteria belonging to Nostocales and Synechococcales clades. Culture-independent methods using Illumina Platform resulted in the identification of 610 Operational Taxonomic Units (OTUs), revealing the presence of populations within phyla Chlorophyta , Cyanobacteria , Rhodophyta and Stramenopiles / Bacillariophyta. In addition, principal component analysis (PCA) and a network analysis were generated and successfully related the different populations to specific biodeterioration scenarios observed at this monument. The use of culture-dependent and -independent techniques together with PCA and network analysis allowed us to understand the distribution patterns of the photoautotrophic community among the different biofilms observed at this monument, as well as their ecological specifications. This study highlights that both cultivation and metagenomics methodologies should be employed synergistically in similar biodeterioration studies. • Culture-dependent and NGS Illumina sequencing of phototrophic populations at the Old Cathedral of Coimbra. • Predominance of microalgae over cyanobacteria among collected samples. • Distinct phototrophic populations associated with different biofilm patterns. • Cultivation and metagenomics approaches revealed to be complementary. [ABSTRACT FROM AUTHOR]

Highlights • Roots and shoots of dill are affected when grown under bicarbonate-induced Fe deficiency. • Shoot biomass was decreased whereas that of roots was not affected. • Reduction of chlorophyll and Fe concentration were registered. • Although distinct polyphenols were found in the plant organs, they were all increased. • This was paralleled by an increment of antioxidant capacity. Abstract This study aimed to investigate the effects of bicarbonate-induced iron deficiency on growth, photosynthetic performance, secondary metabolite content, and related antioxidant capacity in seedlings of Anethum graveolens (L.) grown under controlled conditions in the presence of iron (+Fe) or in induced-iron deficient (+Fe + Bic) media. The main results have shown that dill shoot and plant biomass production significantly decreased under Fe deficiency conditions, whereas that of roots was not affected by such constraint. Moreover, Fe deficiency resulted in a significant reduction of chlorophyll and Fe concentration. Interestingly, when grown under Fe deficiency conditions, A. graveolens was able to increase its shoot iron use efficiency (FeUE). In addition, levels of individual and of total phenolic compounds were shown to be raised in roots as well in leaves. This fact was accompanied by an increased antioxidant activity, as measured through distinct in vitro methods (ABTS+, O 2 −, HO, FRAP and ORAC). The overall data suggests that A. graveolens was able to maintain plant growth and to preserve adequate chlorophyll synthesis under iron-limiting conditions, probably due to its better Fe-use efficiency. The species was also able to modulate secondary metabolites metabolism and its antioxidant capacity, in order to minimize the deleterious effects of reactive oxygen species. [ABSTRACT FROM AUTHOR]

This work focuses on the variability of Retama raetam (Forssk.) Webb bioactive compounds as a function of the plant cycle. The main results showed that it exhibited the highest percentage of polyunsaturated fatty acids, along with superior levels of vitamin C and total phenolic compounds (66.49%, 645.6 mg⋅100 g-1 FW and 23.9 mg GAE⋅g-1, respectively) at the vegetative stage. Instead, at the flowering and mature fruiting stages, R. raetam (Forssk.) Webb exhibited notable contents of proline (25.4 µmol⋅g-1 DW) and carotenoids (27.2 µg⋅g-1 FW), respectively. The gathered data concerning the antioxidant activity highlighted the effectiveness of the vegetative stage in comparison to the other periods. Actually, IC50 and EC50 values of the hydromethanolic extract obtained from the plant shoots at the vegetative stage were of 23, 380, 410, 1160 and 960 µg⋅mL-1 (DPPH· and ABTS·+ radicals scavenging activity, reducing power, chelating power and β-carotene bleaching activity, respectively). Furthermore, the four studied stages showed appreciable antibacterial capacities against human pathogens with a higher efficiency of the vegetative stage extract. Finally, the LC-DAD-ESI/MSn analysis revealed the predominance of isoflavonoids as main class of phenolic compounds and demonstrates that individual phenolic biosynthesis was clearly different as a function of plant growth. These findings highlight that reaching the optimum efficiency of R. raetam (Forssk.) Webb is closely linked to the physiological stage. [ABSTRACT FROM AUTHOR]

Since the first clinical case reported more than 100 years ago, it has been a long and winding road to demystify the initial pathological events underling the onset of Alzheimer’s disease (AD). Fortunately, advanced imaging techniques extended the knowledge regarding AD origin, being well accepted that a decline in brain glucose metabolism occurs during the prodromal phases of AD and is aggravated with the progression of the disease. In this sense, in the last decades, the post-translational modification O -linked β- N -acetylglucosaminylation ( O -GlcNAcylation) has emerged as a potential causative link between hampered brain glucose metabolism and AD pathology. This is not surprising taking into account that this dynamic post-translational modification acts as a metabolic sensor that links glucose metabolism to normal neuronal functioning. Within this scenario, the present review aims to summarize the current understanding on the role of O -GlcNAcylation in neuronal physiology and AD pathology, emphasizing the close association of this post-translational modification with the emergence of AD-related hallmarks and its potential as a therapeutic target. [ABSTRACT FROM AUTHOR]

The potent relation between lycopene intake and reduced incidence of a variety of cancers has an increasing interest. This comprehensive review aims to highlight the in vivo and in vitro research evaluating the anticancer mechanisms of lycopene by underlining the experiment conditions. In addition to these, the general characterization of lycopene has been explained. A collection of relevant scientific pharmacological articles from the following databases PubMed/MedLine, Web of Science, Scopus, TRIP database, and Google Scholar on the mechanisms of anticancer molecular action and cellular effects of lycopene in various types of tumors was performed. The anticancer potential of lycopene has been described by various in vitro cells, animal studies, and some clinical trials. It has been revealed that the anticancer potential of lycopene is mainly due to its powerful singlet-oxygen quencher characteristics, simulation of detoxifying/antioxidant enzymes production, initiation of apoptosis, inhibition of cell proliferation and cell cycle progression as well as modulations of gap junctional communication, the growth factors, and signal transduction pathways. It has been highlighted that the anticancer properties of lycopene are primarily linked to factors including; dose, presence of drug delivery systems, type of cancer, tumor size, and treatment time. [Display omitted] • Lycopene is a fat-soluble red-colored carotenoid with many pharmacological properties. • This review describes the latest data on molecular characterization, anticancer and antitumor molecular mechanisms. • The anticancer activity of lycopene is due to changing many pathways that trigger cell growth or cell death. • Lycopene inhibitis cell proliferation, cell cycle progression and induction of apoptosis [ABSTRACT FROM AUTHOR]

Thymus plants are marketed for diverse usages because of their pleasant odor, as well as high nutritional value and wealth of health-promoting phytochemicals. In this study, Thymuszygis, Thymuspulegioides, and Thymusfragrantissimus grown under organic cultivation regime were characterized regarding nutrients and phenolic compounds. In addition, the antioxidant and antibacterial properties of these species were screened. The plants were particularly notable for their high K/Na ratio, polyunsaturated fatty acids content and low omega-6/omega-3 fatty acids ratios, which are valuable features of a healthy diet. Caffeic acid and/or its derivatives, mainly rosmarinic acid and caffeoyl rosmarinic acid, represented the majority of the phenolic constituents of these plants, although they were less representative in T. pulegioides, which in turn was the richest in flavones. The latter species also exhibited the highest antioxidant capacity (DPPH● EC50 of 9.50 ± 1.98 μg/mL and reducing power EC50 of 30.73 ± 1.48 μg/mL), while T. zygis was the most active towards Gram-positive and Gram-negative bacteria. Overall, the results suggest that the three thyme plants grown in organic farming are endowed with valuable metabolites that give them high commercial value for applications in different industries. [ABSTRACT FROM AUTHOR]

Active coating development for prevention and control of microbial contamination is an extremely challenging technology. In this field, the potential of plant-based compounds to be used as a complement or an alternative to the synthetic preservatives have drawn increasing attention from the food industry. In this study, an active coating containing Origanum virens essential oil (EO-WPC) was applied on the surface of two traditional Portuguese sausages ( paínhos and alheiras ) during industrial production. For 4 months, both products were regularly monitored for their physicochemical properties and total microbial load. Sensory evaluation was also carried out for each sausage type. The application of the EO-WPC caused little variations on the moisture content and texture profile. Higher acidity and protection against color fading was observed particularly in paínhos, while coated alheiras had a significant reduction of the lipid peroxidation. Inhibition of the total microbial load was observed for both coated sausages, resulting in an extension of the shelf life of approximately 20 and 15 days for paínhos and alheiras, respectively. Sensory analysis revealed an overall positive acceptance. These results support the great potential of O. virens EO to be used as food preservative in processed meat products. [ABSTRACT FROM AUTHOR]

To study structure-function relationships of pectic polysaccharides with their immunostimulatory activity, broccoli by-products were used. Pectic polysaccharides composed by 64 mol% uronic acids, 18 mol% Ara, and 10 mol% Gal, obtained by hot water extraction, activated B lymphocytes in vitro (25–250 μg/mL). To disclose active structural features, combinations of ethanol and chromatographic fractionation and modification of the polysaccharides were performed. Polysaccharides insoluble in 80 % ethanol (Et80) showed higher immunostimulatory activity than the pristine mixture, which was independent of molecular weight range (12–400 kDa) and removal of terminal or short Ara side chains. Chemical sulfation did not promote B lymphocyte activation. However, the action of pectin methylesterase and endo -polygalacturonase on hot water extracted polysaccharides produced an acidic fraction with a high immunostimulatory activity. The de-esterified homogalacturonan region seem to be an important core to confer pectic polysaccharides immunostimulatory activity. Therefore, agri-food by-products are a source of pectic polysaccharide functional food ingredients. [Display omitted] • Pectic polysaccharides from broccoli by-products activate B lymphocytes. • Immunostimulation do not rely on terminal arabinose and molecular weight. • Chemical sulfation does not impact immunostimulatory activity. • De-esterified homogalacturonan regions are an important core for activity. [ABSTRACT FROM AUTHOR]