Low-molecular-weight components of olive oil mill wastewaters

A new lignan 1-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-6-(3-acetyl-4-hydroxy-5-methoxyphenyl)-3,7-dioxabicyclo[ 3.3.0]octane, the secoiridoid 2H-pyran-4-acetic acid,3-hydroxymethyl-2,3-dihydro-5-(methoxycarbonyl)-2- methyl-, methyl ester, the phenylglycoside 4-[β -D-xylopyranosyl-(1→6)]-β -D-glucopyranosyl-1,4-dihydroxy-2- methoxybenzene and the lactone 3-[1-(hydroxymethyl)-1-propenyl] δ -glutarolactone were isolated and identified on the basis of spectroscopic data including two-dimensional NMR, as components of olive oil mill waste-waters. The known aromatic compounds catechol, 4-hydroxybenzoic acid, protocatechuic acid, vanillic acid, 4-hydroxy- 3,5-dimethoxybenzoic acid, 4-hydroxyphenylacetic acid, 3,4-dihydroxyphenylacetic acid, tyrosol, hydroxytyrosol, 2-(4-hydroxy-3-methoxy)phenylethanol, 2-(3,4-dihydroxy)phenyl-1,2-ethandiol, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, 1-O-[2-(3,4-dihydroxy)phenylethyl]-(3,4-dihydroxy)phenyl-1,2-ethandiol, 1-O-[2-(4- hydroxy)phenylethyl]-(3,4-dihydroxy)phenyl-1,2-ethandiol, D(+)-erythro-1-(4-hydroxy-3-methoxy)-phenyl-1,2,3- propantriol, p-hydroxyphenethyl-β-D-glucopyranoside, 2(3,4-dihydroxyphenyl)ethanol 3β-D-glucopyranoside, and 2(3,4-dihydroxyphenyl)ethanol 4β-D-glucopyranoside were also confirmed as constituents of the waste-waters

Unusual products of the aqueous chlorination of atenolol

The reaction of the drug atenolol with hypochlorite under conditions that simulate wastewater disinfection was investigated. The pharmaceutical reacted in 1 h yielding three products that were separated by chromatographic techniques and characterized by spectroscopic features. Two unusual products 2-(4-(3-(chloro(2-chloropropan- 2-yl)amino)-2-hydroxypropoxy) phenyl) acetamide and 2-(4- (3-formamido- 2-hydroxypropoxy) phenyl) acetamide were obtained along with 2-(4-hydroxyphenyl) acetamide. When the reaction was stopped at shorter times only 2-(4-(3-amino-2-hydroxypropoxy) phenyl) acetamide and the dichlorinated product were detected. Tests performed on the seeds of Lactuca sativa show that chlorinated products have phytotoxic activity

Striking Dependence of Protein Sweetness on Water Quality: The Role of the Ionic Strength

Sweet proteins are the sweetest natural molecules. This aspect prompted several proposals for their use as food additives, mainly because the amounts to be added to food would be very small and safe for people suffering from sucrose-linked diseases. During studies of sweet proteins as food additives we found that their sweetness is affected by water salinity, while there is no influence on protein’s structure. Parallel tasting of small size sweeteners revealed no influence of the water quality. This result is explained by the interference of ionic strength with the mechanism of action of sweet proteins and provides an experimental validation of the wedge model for the interaction of proteins with the sweet receptor

Degradation of lansoprazole and omeprazole in the aquatic environment

Lansoprazole and omeprazole degrade in water leading to sulfides, benzimidazolones and a red complex material. Degradation is accelerated in acid medium and by solar simulator irradiation. Benzimidazoles, dianilines and pyridines have also been identified

Photochemical behavior of the drug atorvastatin in water.

Atorvastatin undergoes a self-sensitized photooxygenation by sunlight in water. The main photoproducts, isolated by chromatographic techniques, have been identified by spectroscopic means. They present a lactam ring arising from an oxidation of pyrrole ring and an alkyl/aryl shift. A mechanism involving singlet oxygen addition and an epoxide intermediate is suggested

TOXICITY OF PREDNISOLONE, DEXAMETHASONE AND THEIR PHOTOCHEMICAL DERIVATIVES ON AQUATIC ORGANISMS

Light exposure of aqueous suspensions of prednisolone and dexamethasone causes their partial phototransformation. The photoproducts, isolated by chromatographic techniques, have been identified by spectroscopic means. Prednisolone, dexamethasone and their photoproducts have been tested to evaluate their acute and chronic toxic effects on some freshwater chain organisms. The rotifer Brachionus calyciflorus and the crustaceans Thamnocephalus platyurus and Daphnia magna were chosen to perform acute toxicity tests, while the alga Pseudokircheneriella subcapitata (formerly known as Selenastrum capricornutum) and the crustacean Ceriodaphnia dubia to perform chronic tests. The photochemical derivatives are more toxic than the parent compounds. Generally low acute toxicity was found. Chronic exposure to this class of pharmaceuticals caused inhibition of growth population on the freshwater crustacean C. dubia while the alga P. subcapitata seems to be less affected by the presence of these drugs

The Origin of Unpleasant Aftertastes in Synthetic Sweeteners: A Hypothesis

Most sweeteners are plagued with unwanted unpleasant aftertastes. Here we examined the possibility that one of the main reasons for this is the similarity of sweet and umami receptors. We performed docking calculations on models of sweet and umami receptors using as template the recently determined solid state structure of the first taste receptor, the medaka fish T1R2-T1R3 receptor. Our results show convincingly that sweeteners can be recognized also by the T1R1-T1R3 umami receptor, owing to the similarity of its architecture to that of the sweet receptor. We hypothesize that the T1R1-T1R3 receptor plays a key role in modulating the quality of sweet tastants, hinting at a simple explanation of their aftertaste. The prevailing ideas on taste coding favor strict labeling of taste cells, which would exclude that umami receptors can recognize other taste sensations. If some cross-talk based on the combinatorial model of taste is accepted, some sweet ligands can exert a bitter sensation. However, even if cross-talk is not admitted, direct stimulation of the umami receptor is bound to cause an aftertaste incompatible with good sweet quality

Traces and Echoes: a methodology for the making of embodied performance

This research is an investigation on how movement practice embedded in the creative process from the very beginning can have a radical effect on the resulting performance. My exploration of the consequences of the use of movement as an integral part of the creative process has been conducted specifically through one major performance making project, and four other different performances that allowed me to further research and systematize a personal method of practice that I called “Traces and echoes”. To contextualize my research, I conducted an historical overview of the possible sources of movement practice as part of actor training and of performance making. I complemented my investigation with the analysis of the creative processes of three contemporary theatre makers, coming from very different theatrical backgrounds, but sharing a strong physical awareness in their creative and rehearsal processes: Kellie Hughes, Lluís Homar and Andrés Corchero

An optimized strategy to measure protein stability highlights differences between cold and hot unfolded states

Macromolecular crowding ought to stabilize folded forms of proteins, through an excluded volume effect. This explanation has been questioned and observed effects attributed to weak interactions with other cell components. Here we show conclusively that protein stability is affected by volume exclusion and that the effect is more pronounced when the crowder's size is closer to that of the protein under study. Accurate evaluation of the volume exclusion effect is made possible by the choice of yeast frataxin, a protein that undergoes cold denaturation above zero degrees, because the unfolded form at low temperature is more expanded than the corresponding one at high temperature. To achieve optimum sensitivity to changes in stability we introduce an empirical parameter derived from the stability curve. The large effect of PEG 20 on cold denaturation can be explained by a change in water activity, according to Privalov's interpretation of cold denaturation

The cold denaturation of IscU highlights structure–function dualism in marginally stable proteins

Proteins undergo both cold and heat denaturation, but often cold denaturation cannot be detected because it occurs at temperatures below water freezing. Proteins undergoing detectable cold as well as heat denaturation yield a reliable curve of protein stability. Here we use bacterial IscU, an essential and ancient protein involved in iron cluster biogenesis, to show an important example of unbiased cold denaturation, based on electrostatic frustration caused by a dualism between iron–sulfur cluster binding and the presence of a functionally essential electrostatic gate. We explore the structural determinants and the universals that determine cold denaturation with the aid of a coarse grain model. Our results set a firm point in our understanding of cold denaturation and give us general rules to induce and predict protein cold denaturation. The conflict between ligand binding and stability hints at the importance of the structure–function dualism in protein evolution. Proteins can undergo both heat and cold denaturation, and in marginally stable proteins this is often controlled by electrostatic frustration. Here, the authors find that residues essential for protein function are also structural determinants for cold denaturation