Effect of heat treatment on the antioxidant activities of camel milk alpha, beta and total caseins.

This study aimed to evaluate the effect of various heating temperatures on the antioxidant activities of camel milk caseins. The samples were processed with three different heat treatments: Pasteurization at low and high temperatures and boiling. Fresh camel milk (unheated) was used as a control. Camel milk caseins were separated by fast ion exchange liquid chromatography (FPLC) and identified by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS page). The antioxidant activities of caseins were measu- red by three different in vitro methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2, 2'-azino-bis (3-ethylbenzthiazoline-6-sulfonate) (ABTS) radical scavenging activity and ferric reducing power assay (FRAP). The antioxidant activity evaluated by the DPPH assay decreased significantly (p<0.05) with the increase in heat treatment of caseins. However, there was no significant difference in ABTS radical scavenging activity and Ferric Reducing Antioxidant Power assay (FRAP) of heat-treated camel caseins compared to unheated onesStill, a decrease was observed in those activities by the increase of temperature in the different casein concentrations. Besides, whatever the concentration tested and the methods applied, the antioxidant activity of beta-casein (ß-CN) was more pronounced than the alpha-casein (α-CN). Therefore, camel milk casein could be used as a natural source of antioxidants which may have a potential application in the food and nutraceutical industries. Throughout the different heat treatments applied, pasteurization at low temperature could be the most suitable alternative to preserve the antioxidant properties of camel milk.

Metabolome-microbiome signatures in the fermented beverage, Kombucha.

Kombucha is a fermented tea. Here we investigate the fermentation kinetics, metabolite production, microbiome and potential health promoting properties of three different kombucha consortia. Shotgun metagenomic sequencing revealed several dominant bacterial genera such as Komagataeibacter, Gluconacetobacter and Gluconobacter. Brettanomyces and Schizosaccharomyces were the most dominant yeasts identified. Species distribution reflected different patterns of sugar consumption, with S. pombe being present in samples with the highest sugar conversion. Liquid-liquid extractions were performed with organic solvents in order to obtain dried extracts, which were later characterized. HPLC-DAD and GC-MS analysis revealed differences in the production of organic acids, sugars, alcohols and phenolic compounds, where the presence of caffeine, propanoic acid and 2,3 butanediol differ greatly across the three kombuchas. Metabolomic analysis exhibited a link between the microbiota and the production of bioactive compounds in kombucha fermentation. In vitro assays were carried out in order to evaluate potential health-promoting features of the fermented teas, with notable outcomes including antioxidant ability against DPPH radical and against the 15-lipoxygenase enzyme, indicating a potential anti-inflammatory activity. These investigations considerably enhance our understanding of the relationship between the microbiota and metabolites as well as health promoting potential of kombucha and have the potential for the development of future generations of kombucha products in which these relationships are optimized.

Evolution of Polyphenols during Syrah Grapes Maceration: Time versus Temperature Effect.

The effect of maceration time and temperature on the phenolic compounds of Syrah grape musts was studied. Pre-fermentation cold (10 °C) and heat maceration (60, 70 and 80 °C) were applied and compared to traditional maceration (control, 25 °C). The macerations were monitored and the kinetic profile of the maceration was studied by taking samples at 0, 2, 4, 8, 24 and 48 h. The results showed that heat treatment had the most significant effect on the extraction of total polyphenol. A significant loss of anthocyanin content was observed when the maceration was extended beyond eight hours at high temperatures, while longer maceration times seemed to favor the extraction of tannins. A principal component analysis showed that independently of the vinification technique, and for the same grape varieties, different winegrowing regions and harvest years affected the phenolic composition of the grape skin.

Understanding Kombucha Tea Fermentation: A Review.

Kombucha is a beverage of probable Manchurian origins obtained from fermented tea by a microbial consortium composed of several bacteria and yeasts. This mixed consortium forms a powerful symbiosis capable of inhibiting the growth of potentially contaminating bacteria. The fermentation process also leads to the formation of a polymeric cellulose pellicle due to the activity of certain strains of Acetobacter sp. The tea fermentation process by the microbial consortium was able to show an increase in certain biological activities which have been already studied; however, little information is available on the characterization of its active components and their evolution during fermentation. Studies have also reported that the use of infusions from other plants may be a promising alternative. PRACTICAL APPLICATION: Kombucha is a traditional fermented tea whose consumption has increased in the recent years due to its multiple functional properties such as anti-inflammatory potential and antioxidant activity. The microbiological composition of this beverage is quite complex and still more research is needed in order to fully understand its behavior. This study comprises the chemical and microbiological composition of the tea and the main factors that may affect its production.

Drug Release by Direct Jump from Poly(ethylene-glycol-b-ε-caprolactone) Nano-Vector to Cell Membrane.

Drug delivery by nanovectors involves numerous processes, one of the most important being its release from the carrier. This point still remains unclear. The current work focuses on this point using poly(ethyleneglycol-b-ε-caprolactone) micelles containing either pheophorbide-a (Pheo-a) as a fluorescent probe and a phototoxic agent or fluorescent copolymers. This study showed that the cellular uptake and the phototoxicity of loaded Pheo-a are ten times higher than those of the free drug and revealed a very low cellular penetration of the fluorescence-labeled micelles. Neither loaded nor free Pheo-a displayed the same cellular localization as the labeled micelles. These results imply that the drug entered the cells without its carrier and probably without a disruption, as suggested by their stability in cell culture medium. These data allowed us to propose that Pheo-a directly migrates from the micelle to the cell without disruption of the vector. This mechanism will be discussed.

Synthesis, cytotoxic, anti-lipoxygenase and anti-acetylcholinesterase capacities of novel derivatives from harmine.

We synthesized two series of new hydrazide harmine derivatives. The reaction of harmine 1 with ethyl acetate chloride afforded the corresponding ethyl ester 2. The treatment of 2 with hydrazine hydrate gave the hydrazide 3 which further converted into hydrazones 4a-j and dihydrazides 5a-c. A series of new triazoles 7a-f has also been prepared from the suitable propargyl harmine 6. The synthesized derivatives were characterized by 1H-NMR, 13C-NMR, and HRMS and evaluated for their activities against MCF7, HCT116 OVCAR-3, acetylcholinesterase and 5-lipoxygenase. The most hydrazones derivatives 4a-j have a good cytotoxic activity against all cell lines, when 4a, 4d, 4f and 4 g are more active than 1 (against OVCAR-3 IC50 16.7-2.5 µM). The compound 6 was the most active (IC50 = 1.9 µM) against acetylcholinesterase. Some compounds exhibited significant activity against 5-lipoxygenase (IC50 = 30.9-63.1 µM).

Antioxidant, 5-lipoxygenase inhibitory and cytotoxic activities of compounds isolated from the Ferula lutea flowers.

A phytochemical investigation of the Ferula lutea (Poir.) Maire flowers has led to the isolation of a new compound, (E)-5-ethylidenefuran-2(5H)-one-5-O-ß-d-glucopyranoside (1), designated ferunide, 4-hydroxy-3-methylbut-2-enoic acid (2), reported for the first time as a natural product, together with nine known compounds, verbenone-5-O-ß-d-glucopyranoside (3), 5-O-caffeoylquinic acid (4), methyl caffeate (5), methyl 3,5-O-dicaffeoylquinate (6), 3,5-O-dicaffeoylquinic acid (7), isorhamnetin-3-O-α-l-rhamnopyranosyl(1→6)-ß-d-glucopyranoside, narcissin (8), (-)-marmesin (9), isoimperatorin (10) and 2,3,6-trimethylbenzaldehyde (11). Compounds 3-10 were identified for the first time in Ferula genus. Their structures were elucidated by spectroscopic methods, including 1D and 2D NMR experiments, mass spectroscopy and X-ray diffraction analysis (compound 2), as well as by comparison with literature data. The antioxidant, anti-inflammatory and cytotoxic activities of isolated compounds were evaluated. Results showed that compound 7 exhibited the highest antioxidant activity with IC50 values of 18 ± 0.5 µmol/L and 19.7 ± 0.7 µmol/L by DPPH radical and ABTS radical cation, respectively. The compound 6 exhibited the highest anti-inflammatory activity with an IC50 value of 5.3 ± 0.1 µmol/L against 5-lipoxygenase. In addition, compound 5 was found to be the most cytotoxic, with IC50 values of 22.5 ± 2.4 µmol/L, 17.8 ± 1.1 µmol/L and 25 ± 1.1 µmol/L against the HCT-116, IGROV-1 and OVCAR-3 cell lines, respectively.

Role of intercalation and redox potential in DNA photosensitization by ruthenium(II) polypyridyl complexes: assessment using DNA repair protein tests.

Here we report that the photoreactivity of ruthenium(II) complexes with nucleobases may not only be modulated by their photoredox properties but also by their DNA binding mode. The damage resulting from photolysis of synthetic oligonucleotides and plasmid DNA by [Ru(bpz)3](2+), [Ru(bipy)3](2+) and the two DNA intercalating agents [Ru(bpz)2dppz](2+) and [Ru(bipy)2dppz](2+) has been monitored by polyacrylamide gel electrophoresis and by tests using proteins involved in DNA repair processes (DNA-PKCs, Ku80, Ku70, and PARP-1). The data show that intercalation controls the nature of the DNA damage photo-induced by ruthenium(II) complexes reacting with DNA via an electron transfer process. The intercalating agent [Ru(bpz)2dppz](2+) is a powerful DNA breaker inducing the formation of both single and double (DSBs) strand breaks which are recognized by the PARP-1 and DNA-PKCs proteins respectively. [Ru(bpz)2dppz](2+) is the first ruthenium(II) complex described in the literature that is able to induce DSBs by an electron transfer process. In contrast, its non-intercalating parent compound, [Ru(bpz)3](2+), is mostly an efficient DNA alkylating agent. Photoadducts are recognized by the proteins Ku70 and Ku80 as with cisplatin adducts. This result suggests that photoaddition of [Ru(bpz)2dppz](2+) is strongly affected by its DNA intercalation whereas its photonuclease activity is exalted. The data clearly show that DNA intercalation decreases drastically the photonuclease activity of ruthenium(II) complexes oxidizing guanine via the production of singlet oxygen. Interestingly, the DNA sequencing data revealed that the ligand dipyridophenazine exhibits on single-stranded oligonucleotides a preference for the 5'-TGCGT-3' sequence. Moreover the use of proteins involved in DNA repair processes to detect DNA damage was a powerful tool to examine the photoreactivity of ruthenium(II) complexes with nucleic acids.

Assessment of antioxidant, anti-inflammatory, anti-cholinesterase and cytotoxic activities of pomegranate (Punica granatum) leaves.

This study evaluated antioxidant, anti-inflammatory, anti-cholinesterase and cytotoxic activities of extracts with different polarities (hexane, dichloromethane, ethyl acetate, ethanol and methanol) obtained from Punica granatum leaves. Total phenolics (8.8-127.3mg gallic acid equivalent/g dry weight), flavonoids (1.2-76.9mg quercetin equivalent/g dry weight), tannins (63.7-260.8mg catechin equivalent/kg dry weight) and anthocyanins (0.41-3.73mg cyanidin-3-glucoside equivalent/g dry weight) of different extracts were evaluated. The methanolic extract presented a good IC50 by DPPH and ABTS assays (5.62 and 1.31mg/l respectively). The strongest 5-lipoxygenase (5-LOX), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition activities were obtained for the ethanol extract (IC50 values of 6.20, 14.83 and 2.65mg/l, respectively) and the best cytotoxic activity against MCF-7 cells was obtained for the methanol extract (IC50=31mg/l). These important biological activities showed that P. granatum leaves could be a potential source of the active molecules intended for applications in pharmaceutical industry, but only after additional in vivo experiments.

Global chemical composition and antioxidant and anti-tuberculosis activities of various extracts of Globularia alypum L. (Globulariaceae) leaves.

In this work, an evaluation of the biological activities of Globularia alypum L. extracts and their global chemical composition was realized. Extracts from G. alypum were obtained by two extraction methods. The composition of polyphenols (8.5-139.95 g gallic acid equivalent/Kg of dry mass), tannins (1.39-18.65 g catechin equivalent/Kg of dry mass), anthocyanins (8.17-70.69 mg cyanidin equivalent/Kg of dry mass) and flavonoids (0.31-19.28 g quercetin equivalent/Kg of dry mass) was evaluated. The samples were subjected to a screening for their antioxidant activities using the DPPH* and ABTS*+ assays. For the first time, the anti-tuberculosis activity (H(37)Rv) for G. alypum was tested against Mycobacterium tuberculosis. The strongest antioxidant activity was obtained for the methanol extract (IC(50 ) = 15.58 ± 0.168 mg/L) and the best anti-tuberculosis activity was obtained for the petroleum ether extract (IC(50 )= 77 mg/L). We have found a positive correlation between the total phenolics content and the antioxidant activity R2 = 0.88 (DPPH*) and R2 = 0.97 (ABTS*+). We have found also a positive correlation between the flavonoid content and the antioxidant activity R2 = 0.91 (DPPH*) and R2 = 0.91 (ABTS*+).

Oregano: chemical analysis and evaluation of its antimalarial, antioxidant, and cytotoxic activities.

GC-FID and GC-MS analysis of essential oil from oregano leaves (Origanum compactum) resulted in the identification of 46 compounds, representing more than 98% of the total composition. Carvacrol was the predominant compound (36.46%), followed by thymol (29.74%) and p-cymene (24.31%). Serial extractions with petroleum ether, ethyl acetate, ethanol, and water were performed on aerials parts of Origanum compactum. In these extracts, different chemical families were characterized: polyphenols (gallic acid equivalent 21.2 to 858.3 g/kg), tannins (catechin equivalent 12.4 to 510.3 g/kg), anthocyanins (cyanidin equivalent 0.38 to 5.63 mg/kg), and flavonoids (quercetin equivalent 14.5 to 54.7 g/kg). The samples (essential oil and extracts) were subjected to a screening for antioxidant (DPPH and ABTS assays) and antimalarial activities and against human breast cancer cells. The essential oil showed a higher antioxidant activity with an IC50=2±0.1 mg/L. Among the extracts, the aqueous extract had the highest antioxidant activity with an IC50=4.8±0.2 mg/L (DPPH assay). Concerning antimalarial activity, Origanum compactum essential oil and ethyl acetate extract showed the best results with an IC50 of 34 and 33 mg/mL, respectively. In addition, ethyl acetate extract (30 mg/L) and ethanol extract (56 mg/L) showed activity against human breast cancer cells (MCF7). The oregano essential oil was considered to be nontoxic.

Chemical composition and anticancer and antioxidant activities of Schinus molle L. and Schinus terebinthifolius Raddi berries essential oils.

Essential oils were obtained by steam distillation from berries of Schinus molle L. and Schinus terebinthifolius Raddi originating from southern of Tunisia and analyzed by GC-FID and GC-MS. Among 57 and 62 compounds (%[mg/100 g dry matter]) identified in these oils, the main were alpha-phellandrene (46.52%[1256.15] and 34.38%[859.60]), beta-phellandrene (20.81%[561.74] and 10.61%[265.15]), alpha-terpineol (8.38%[226.26] and 5.60%[140.03]), alpha-pinene (4.34%[117.29] and 6.49%[162.25]), beta-pinene (4.96%[133.81] and 3.09%[77.30]) and p-cymene (2.49%[67.28] and 7.34%[183.40]), respectively. A marked quantity of gamma-cadinene (18.04%[451.05]) was also identified in the S. terebinthifolius essential oil whereas only traces (0.07%[1.81]) were detected in the essential oil of S. molle. The in vitro antioxidant and antiradical scavenging properties of the investigated essential oils were evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Essential oil of S. terebinthifolius expressed stronger antioxidant activity in the ABTS assay, with an IC(50) of 24 +/- 0.8 mg/L, compared to S. molle (IC(50)= 257 +/- 10.3 mg/L). Essential oils were also evaluated for their anticancer activities against human breast cancer cells (MCF-7). S. terebinthifolius essential oil was more effective against tested cell lines (IC(50)= 47 +/- 9 mg/L) than that from S. molle (IC(50)= 54 +/- 10 mg/L). Suggestions on relationships between chemical composition and biological activities are outlined.

Monomeric pheophorbide(a)-containing poly(ethyleneglycol-b-epsilon-caprolactone) micelles for photodynamic therapy.

Incorporation of unaggregated monomeric molecules of pheophorbide(a) into micelles of poly(ethyleneoxide-b-epsilon-caprolactone) has been characterized by fluorescence spectroscopy, dynamic light scattering, transmission electron microscopy and asymmetric flow field flow fractionation. It was shown that the method used leads to 20 nm micelles, corresponding to approximately 200 molecules of polymer and 4 molecules of monomeric pheophorbide(a) per nano-object which was able to generate (1)O(2) in the medium. They have been used thereafter as nanocarriers for photosensitizers in photodynamic therapy against cancer cells. The encapsulation of photosensitizer has been verified and in vitro tests on human cancerous cells have revealed a ca. 2-fold enhanced photocytotoxicity and cellular uptake compared to free pheophorbide(a).

Synthesis of estradiol-pheophorbide a conjugates: evidence of nuclear targeting, DNA damage and improved photodynamic activity in human breast cancer and vascular endothelial cells.

The synthesis, physico-chemical properties, cellular localization and photocytotoxicity of estradiol-pheophorbide a conjugates in estrogen-dependent cancer and vascular endothelial cells are described with the aim of increasing the photodynamic activity by targeting the nucleus of both tumor and blood vessel cells.

Photoelectron transfer processes with ruthenium(II) polypyridyl complexes and Cu/Zn superoxide dismutase.

The processes that are photoinduced by [Ru(bpz)(3)](2+) (bpz = 2,2'-bipyrazyl) in the presence of Cu/Zn superoxide dismutase (Cu/Zn SOD) are investigated by laser flash photolysis and electron paramagnetic resonance (EPR) spectroscopy; they are compared to those of the system [Ru(bpy)(3)(2+)-Cu/Zn SOD]. Although the mechanism is complicated, primary and secondary reactions can be evidenced. First, the excited [Ru(bpz)(3)](2+) complex is quenched reductively by Cu/Zn SOD with the production of a reduced complex and an oxidized enzyme. The oxidation site of Cu/Zn SOD is proposed to correspond to amino acids located on the surface of the protein. Afterward and only when this reductive electron transfer to the excited complex has produced enough oxidized protein, another electron-transfer process can be evidenced. In this case, however, the charge-transfer process takes place in the other direction, i.e., from the excited complex to the Cu(II) center of the SOD with the formation of Ru(III) and Cu(I) species. This proposed mechanism is supported by the fact that [Ru(bpy)(3)](2+), which is less photo-oxidizing than [Ru(bpz)(3)](2+), exhibits no photoreaction with Cu/Zn SOD. Because Ru(III) species are generated as intermediates with [Ru(bpz)(3)](2+), they are proposed to be responsible for the enhancement of [poly(dG-dC)](2) and [poly(dA-dT)](2) oxidation observed when Cu/Zn SOD is added to the [Ru(bpz)(3)](2+)-DNA system.

Radical trapping properties of imidazolyl nitrones.

The ability of ten imidazolyl nitrones to directly scavenge free radicals (R(*)) generated in polar ((*)OH, O(*)(2)(-), SO(*)(3)(-) cysteinyl, (*)CH(3)) or in apolar (CH(3)-(*)CH-CH(3)) media has been studied. When oxygen or sulfur-centered radicals are generated in polar media, EPR spectra are not or weakly observed with simple spectral features. Strong line intensities and more complicated spectra are observed with the isopropyl radical generated in an apolar medium. Intermediate results are obtained with (*)CH(3) generated in a polar medium. EPR demonstrates the ability of these nitrones to trap radicals to the nitrone C(alpha) atom (alpha radical adduct) and to the imidazol C(5) atom (5-radical adduct). Beside the nucleophilic addition of the radical to the C(alpha) atom, the EPR studies suggest a two-step mechanism for the overall reaction of R(*) attacking the imidazol core. The two steps seem to occur very fast with the (*)OH radical obtained in a polar medium and slower with the isopropyl radical prepared in benzene. In conclusion, imidazolyl nitrones present a high capacity to trap and stabilize carbon-centered radicals.

2-substituted-3H-indol-3-one-1-oxides: preparation and radical trapping properties.

A series of 2-alkyl and 2-aryl substituted-3H-indol-3-one-1-oxides was prepared and evaluated for its radical trapping properties. Spin trapping and electron paramagnetic resonance experiments demonstrate the ability of these indolone-1-oxides to trap hetero- and carbon-centered radicals. The most stable spin adducts (lifetime of several hours) are obtained with 2-alkyl substituted nitrones, the 2-ethyl-5,6-dioxolo-3H-indolone-1-oxide, 5e and the 2-secbutyl-3H-indolone-1-oxide, 5f. These two nitrones are also sensitive to redox reactions in solution. Therefore this indolone-1-oxide series lacking a beta-hydrogen atom gives rise to highly stable adducts with free radicals.

Antioxidant properties of trans-epsilon-viniferin as compared to stilbene derivatives in aqueous and nonaqueous media.

trans-Epsilon-viniferin, the dimer of resveratrol, extracted from Vitis vinifera, has been evaluated for its antioxidant capacity. Its properties have been compared to those of resveratrol and synthetic stilbenic derivatives (4-hydroxystilbene, 4,4'-dihydroxystilbene, 3,5-dihydroxystilbene, and trimethylresveratrol), in regard to their liposolubility using two media with different polarity. The bleaching of beta-carotene by lipoperoxyl (LOO.) radicals in an oil/water (O/W) emulsion and the scavenging of superoxide anions (O(-)(2) in dimethyl sulfoxide (DMSO) using 5,5-dimethyl-1-pyrroline-N-oxide as a spin trap were followed using UV-visible and electron paramagnetic resonance, respectively. Epsilon-viniferin exhibits the best antioxidant capacity in the DMSO/O(-)(2) polar system (IC(50) = 0.14 mM) while 4,4'-dihydroxystilbene presents the highest antioxidant capacity in the O/W/LOO. system (inhibition of beta-carotene bleaching, 82%). Partition coefficients and kinetics of partition between 1-octanol and water were measured to discuss the antioxidant efficiency of the compounds in relation with their chemical structure.