Reactions of medicinal gold(III) compounds with proteins and peptides explored by electrospray ionization mass spectrometry and complementary biophysical methods

Electrospray ionization mass spectrometry (ESI MS) is a powerful investigative tool to analyze the reactions of metallodrugs with proteins and peptides and characterize the resulting adducts. Here, we have applied this type of approach to four experimental anticancer gold(III) compounds for which extensive biological and mechanistic data had previously been gathered, namely, Auoxo6, Au2phen, AuL12, and Aubipyc. These gold(III) compounds were reacted with two representative proteins, i.e., human serum albumin (HSA) and human carbonic anhydrase I (hCA I), and with the C-terminal dodecapeptide of thioredoxin reductase. ESI MS analysis allowed us to elucidate the nature of the resulting metal–protein adducts from which the main features of the occurring metallodrug–protein reactions can be inferred. In selected cases, MS data were integrated and supported by independent 1HNMR and UV–Vis absorption measurements to gain an overall description of the occurring processes. From data analysis, it emerges that most of the investigated gold(III) complexes, endowed with an appreciable oxidizing character, undergo quite facile reduction to gold(I); the resulting gold(I) species tightly associate with the above proteins/peptides with a remarkable selectivity for free cysteine residues. In contrast, in the case of the less-oxidizing Aubipyc complex, the gold(III) oxidation state is conserved, and a gold(III) fragment still containing the original ligand is found to be associated with the target proteins. It is notable that the C-terminal dodecapeptide of thioredoxin reductase containing the characteristic –Gly–Cys–Sec–Gly metal-binding motif is able in all cases to trigger gold(III)-to-gold(I) reduction. Our investigation allowed us to identify in detail the nature of the gold fragments that ultimately bind the protein targets and determine the exact binding stoichiometry; some insight on the reaction kinetics was also gained. Notably, a few clear correlations could be established between the structure of the metal complexes and the nature of the resulting protein adducts. The mechanistic implications of these findings are analyzed and thoroughly discussed. Overall, the present results set the stage to better understand the real target biomolecules of these gold compounds and elucidate at the atomic level their interaction modes with proteins and peptides

A New Configuration of Vertical Axis Wind Turbine: Towards the Development of a highly distributed and efficient Wind Power Generation

Preliminary results obtained for a new configuration lift based vertical-axis wind turbine are shown. The turbine rotor is a cross flow fan type made with high curvature aerodynamic profiles. A reduced scale model of the turbine rotor has been designed and preliminary tested at the Department of Aerospace Engineering of the University of Pisa (rotor diameter 250 mm, rotor height 210 mm). The reduced scale model shows an efficiency of about eighteen per cent. The rotor is of a self-starting type. Two-dimensional CFD analyses have been performed applying both the Moving Reference Frame and the Moving Mesh conditions to the grid which surrounds the rotor blades (Fluent® Rel. 6.3 and STAR-CCM+® Rel. 6.04 have been used). Noticeable scale effects have been found numerically, so, the efficiency of a full scale lift based vertical axis multi-blades optimized wind turbine is expected to be comparable with lift based horizontal-axis wind turbines

Greenhouse gas emissions in the agricultural phase of wine production in the Maremma rural district (Tuscany, Italy).

In recent years, there has been an increasing interest from retailers, industries and environmental associations in estimating the life cycle of greenhouse gases emitted in the atmosphere from everyday products and services, also known as carbon footprint (CF). Life cycle assessment (LCA) is the most common methodology used to evaluate the environmental impact of a product. This approach was largely used in many industrial sectors and was also recently applied to quantify the environmental impact of the agri-food chain. Within agri-food products, wine is one of the most analysed, both for its importance in economic production and in the world distribution market. The present study is a part of the Carbon Label Project carried out in the wine production chain in the Maremma rural district (Tuscany, Italy). The project assessed the greenhouse gas (GHG) emissions from wine production for labelling purposes. Here, we evaluated the environmental performances of four high quality wines for carbon labelling. The international standards ISO 14040, ISO 14044, and the Product Category Rules (PCR) Wine from Fresh Grapes (except sparkling wine) and Grape Must for the Environmental Product Declaration (EPD) certification, specifically for Climate Declaration, were used in order to carry out our analyses. The functional unit (FU) used here was one 0.75 L bottle of wine. The system boundaries were set from the vineyard planting to the distribution and waste disposal. The global warming potential (GWP) of four investigated wines was found to lie between 0.6 and 1.3 kg CO2-eq./bottle, showing a value comparable with literature. With all the four wines analysed, the agricultural phase covered, on average, 22% of the total GWP/bottle, while the main impact was in the production of the glass bottle. The results showed that the vineyard-planting phase has a significant impact on the wine CF, thus it has to be considered in the life cycle, while in literature it is frequently omitted. On the contrary, the pre-production phase did not present a relevant impact. The use of nitrogen fertilisers, the grapes’ yield and N2O emissions were the parameters that mostly affected the carbon footprint in the agricultural phase, as underlined by the sensitivity analysis

Influences of postharvest storage and processing techniques on antioxidant and nutraceutical properties of rubus idaeus l.: A mini-review

The growth of agricultural mechanization has promoted an increase in raspberry production, and for this reason, the best postharvest storage and processing techniques capable of maintaining the health beneficial properties of these perishable berry fruits have been widely studied. Indeed, raspberries are a rich source of bioactive chemical compounds (e.g., ellagitannins, anthocyanins, and ascorbic acid), but these can be altered by postharvest storage and processing techniques before consumption. Although there are clear differences in storage times and techniques, the content of bioactive chemical compounds is relatively stable with some minor changes in ascorbic acid or anthocyanin content during cold (5◦C) or frozen storage. In the literature, processing techniques such as juicing or drying have negatively affected the content of bioactive chemical compounds. Among drying techniques, hot air (oven) drying is the process that alters the content of bioactive chemical compounds the most. For this reason, new drying technologies such as microwave and heat pumps have been developed. These novel techniques are more successful in retaining bioactive chemical compounds with respect to conventional hot air drying. This mini-review surveys recent literature concerning the effects of postharvest storage and processing techniques on raspberry bioactive chemical compound content

Differences in pigment circadian rhythmicity in green- and red-leafed tree species in the sun and shade

Light flux and quality are crucial factor for setting endogenous plant circadian rhythms. Evaluating the daily rhythmicity of leaf chlorophyll content is an effective method to monitor the plant physiological endogenous clock in response to environmental signals such as light availability/quality. Here, we used a leaf-clip sensor to monitor diurnal rhythms in the content of chlorophyll and flavonoids such as flavonols and anthocyanins in three green- (Ailanthus altissima, Tilia platyphyllos and Platanus x acerifolia) and two red-leafed (Acer platanoides cv. Crimson King and Prunus cerasifera var. pissardii) tree species, adapted to sun (L) or shade (S). Significant differences in chlorophyll content (Chl) and its variations during the day were observed among treatments in all the analyzed species. S-plants had more Chl than L-plants irrespective of leaf color, and Chl variations were more distinct during the day than in L-plants. In particular, contents were lowest in the morning (9:00) and in the middle of the day (at 12:00 and 15:00), and the highest at dusk (21:00). The less evident trends in Chl variation in L-plants were attributed to a decrease in Chl content in high light, which likely masked any increases in the shaded counterparts during the afternoon. Daily flavonol levels did not vary no notably during the day. In sun-exposed red leaves, anthocyanins partially screened mesophyll cells from incident light, and its levels were similar to the Chl dynamics in the shaded counterparts. This study provides new bases for further work on endogenous rhythms of plant pigments and improves our understanding of plant physiology in the context of day/night rhythmicity

Application of Vis/Nir spectroscopy to establish peach ripening as affected by rootstock

The objective of this paper was to monitor peach ripeness of “Chimarrita” and “Maciel” cultivars, grafted on different rootstocks, using the pulp firmness parameter, as an indicator of harvest time through equipment based on Vis/Nir spectroscopy. The orchard was installed in 2005, has a "V" conduction system with spacing of 5.0 x 1.5 m, and the cultivars are grafted on seven rootstocks: “Capdeboscq”, “Flordaguard”, “Nemaguard”, “Okinawa”, “Tsukuba”, “Umezeiro” and “Viamão”. After harvesting, the fruits were evaluated by the NIR CASE spectrophotometer, establishing categories of pulp firmness, between 40N and 60N for fruits consumed in a long term and <40N for immediate consumption. The analyzed rootstocks alter the peach ripeness of the “Chimarrita” and “Maciel” cultivars. The “Umezeiro” rootstock anticipates harvest for the “Chimarrita” cultivar. The “Nemaguard”/ “Maciel” combination provides fruits with a superior harvest period than the other ones evaluated. The Vis/Nir Spectroscopy is a useful tool to monitor the harvest of “Chimarrita” and “Maciel” cultivars

Nutritional and nutraceutical properties of raw and traditionally obtained flour from chestnut fruit grown in Tuscany

The study of local chestnut and traditional techniques related to their use and consumption are considered of primary importance to promote their nutritional/nutraceutical values. Fruit of four local chestnut cultivars (‘Carpinese’, ‘Pontecosi’, ‘Capannaccia’ and ‘Morona’) from Garfagnana (Italy) were analysed under nutritional and antioxidant aspects and compared with their flour obtained through a traditional thermal-drying process. Raw fruit contained significative amounts of P, K and Mg (~ 149, 1960 and 50&nbsp;mg 100&nbsp;g−1 dry weight, respectively) and they were characterised by a good moisture content (~ 49%) and starch (~ 50&nbsp;g 100&nbsp;g−1 dw). The traditional thermal-drying processes affected the carbohydrate content of dried chestnut showing a higher sucrose and lower starch content as compared to raw fruits. Traditional thermal-drying processes negatively influenced also total phenol content (TP) and total antioxidant activity: flours from all cultivars contained lower amounts of TP than raw fruit except for ‘Morona’ in which these compounds remained unchanged. This study provides new useful information about the evaluation of nutritional and nutraceutical characteristics of Tuscany local chestnuts and the effects of a traditional thermal-drying processing method, helping consumers and producers to valorise these “forest products”