Smenamides A and B,Chlorinated Peptide/Polyketide Hybrids Containing a Dolapyrrolidinone Unit from the Caribbean Sponge Smenospongia aurea. Evaluation of Their Role as Leads in Antitumor Drug Research

An in-depth study of the secondary metabolites contained in the Caribbean sponge Smenospongia aurea led to the isolation of smenamide A (1) and B (2), hybrid peptide/polyketide compounds containing a dolapyrrolidinone unit. Their structures were elucidated using high-resolution ESI-MS/MS and homo- and heteronuclear 2D NMR experiments. Structures of smenamides suggested that they are products of the cyanobacterial metabolism, and 16S rRNA metagenomic analysis detected Synechococcus spongiarum as the only cyanobacterium present in S. aurea. Smenamides showed potent cytotoxic activity at nanomolar levels on lung cancer Calu-1 cells, which for compound 1 is exerted through a clear pro-apoptotic mechanism. This makes smenamides promising leads for antitumor drug design.     

Application of a low-cost camera on a UAV to estimate maize nitrogen-related variables

Precision Agriculture - The development of small unmanned aerial vehicles and advances in sensor technology have made consumer digital cameras suitable for the remote sensing of vegetation. In this...     

Effects of including bioactive legumes in grass silage on digestion parameters,nitrogen balance and methane emissions in sheep

The aim of this work was to investigate the effects of feeding sheep with silage mixtures containing bioactive legumes on intake and digestive parameters. The bioactive legumes used were sainfoin (SF, Onobrychis viciifolia) and red clover (RC, Trifolium pratense), which contain condensed tannins (CT) and polyphenol oxidase respectively. Five treatments were assigned to two groups of sheep according to a replicated 5 × 5 Latin square design. The five types of silages tested were, on a dry matter (DM) basis: pure timothy grass silage (Phleum pratense, control, T), three binary mixtures of T‐SF, T‐RC and RC‐SF (500 g/kg each) and a ternary mixture of T‐RC‐SF (500, 250 and 250 g/kg respectively). The daily voluntary DM intake of silage mixtures containing both SF and RC was greater than for pure T silage, while the presence of SF resulted in lower organic matter digestibility compared to pure T. The rumen disappearance rate measured in situ increased linearly with the presence of SF and RC in silage. The nitrogen (N) digestibility was greater for pure T and T‐RC than for T‐SF, and the amount of N retained daily by the animals was greater for RC‐containing silages than for T and T‐SF. The methane (CH₄) yield was greater for pure T than for the silage mixtures containing SF. We conclude that the presence of RC in silage could boost performances through intake and N retention, while SF‐based mixtures appear to have reduced negative environmental impacts through the reduction of CH₄ emissions.     

Evaluation of the combined effects of enzymatic treatment and aging on lees on the aroma of wine from Bombino bianco grapes

In this study, two different doses of commercial beta-glucanase enzyme preparation were tested to verify their effect on wines aged on lees. These wines were compared with two samples with no enzymatic treatment. The former was aged on lees (control), and the latter was readily filtered off from the yeast cell biomass (standard). Analysis of variance (one-way ANOVA), the Tukey test, and principal component analysis (PCA) were applied to all of the samples, which were analyzed for aroma composition, along with galacturonic acid, total acidity, pH, and color. Results showed a large number of statistically significant differences among samples. In general, wines treated with beta-glucanase were characterized by higher concentration of many volatile compounds. The presence of lees and even more the exogenous enzymatic action enhanced almost all volatile compounds. Besides the high presence of ethyl esters, it is worth mentioning the behavior of hexanol and trans-3-hexenol, which are strongly enhanced by the presence of lees and by enzymatic treatments.     

Synthesis and phytotoxic activity of ozonides

The [4 + 3] cycloaddition of the proper furans with the oxyallyl cation, generated in situ from 2,4-dibromopentan-3-one, produced a series of 8-oxabicyclo [3.2.1]oct-6-en-3-ones. Exposure of the oxabicycles to ozone afforded the corresponding 8,9,10,11-tetraoxatricyclo[5.2.1.1 (2,6)]undecan-4-ones in variable yields (7-100%). The phytotoxic properties of these ozonides (or 1,2,4-trioxolanes) and their oxabicycle precursors were evaluated as the ability to interfere with the growth of Sorghum bicolor and Cucumis sativus seedlings. Among oxabicycles, the highest inhibitory activity was shown by compounds possessing a alpha,beta-unsaturated carbonyl moiety. A differential sensitivity of the two crops was evident with ozonides. The most active compounds were also tested against the weed species Ipomoea grandifolia and Brachiaria decumbens. To the best of our knowledge, this is the first article describing ozonides as potential herbicides.     

Interactions of three s-triazines with humic acids of different structure

The adsorption of three s-triazines (atrazine, terbutylazine, and simazine) on three different humic acids (HAs), before and after acidic hydrolysis, was studied at four diverse pH values from 3 to 4.5. The Freundlich sorption affinity (K(f)) and intensity (1/n) of s-triazines were related to the chemical and structural composition of HA and used in a multivariate statistical analysis. At low pH, the sorption values for s-triazines were not directly justified by the content of carboxyl groups in original HA, while only an increase of phenolic carbons in hydrolyzed HA supported the increased s-triazine adsorption. The structural composition of both s-triazines and humic samples explained 86% of the significance in multivariate analyses, whereas the role of pH remained hidden in only 14% of the statistical significance. Adsorption of s-triazines was mainly related to carbon content, hydrophobicity, and aromaticity of HA, thereby implying a predominant binding role of weak dispersive forces. Steric properties explained the larger adsorption affinity of atrazine and terbutylazine with respect to simazine. The occurrence of charge-transfer interactions between atrazine and mainly hydrolyzed HA was further suggested by the increased number of free radicals detected in atrazine-HA complexes at different pH values. Charge-transfer interactions were postulated to occur when HA conformations became progressively controlled by aromatic components. This work indicates that humic matter rich in hydrophobic and aromatic constituents is more likely to adsorb s-triazines and reduce their environmental mobility.     

Optimization of solid-liquid extraction of resveratrol and other phenolic compounds from milled grape canes (Vitis vinifera)

Optimization of the solid-liquid extraction conditions for trans-resveratrol, trans--viniferin, ferulic acid, and total phenolics from milled grape canes has been investigated. The temperature and ethanol concentration were found to be major process variables for all responses, whereas the solvent to solid ratio was found not to be significant for any of the responses studied. The yields of trans-resveratrol, trans--viniferin, and total phenolics increased with increasing temperature. Maximum yields of trans-resveratrol (4.25 mg/g dw), trans--viniferin (2.03 mg/g), and total phenolics (9.28 mg/g dw) were predicted from the combination of a moderate ethanol concentration (50-70%) and the highest temperature (83.6 degrees C), whereas an ethanol concentration of 35% at the lowest temperature studied (16.4 degrees C) was optimal for the extraction of ferulic acid (1.05 mg/g dw). Effective diffusivity values of resveratrol in the solid phase, D eff for different extraction conditions, were calculated by fitting the experimental results to a model derived from the Fick's second law. Effective diffusivity of resveratrol in the solid phase varied from 3.1 x 10 (-13) to 26.6 x 10 (-13) m (2) s (-1) with changing extraction conditions. The increase in effective diffusivity of resveratrol was observed with increasing temperature, and the highest predicted level was obtained when using 54% ethanol/water mixture at 83.6 degrees C. The increase in ethanol concentration exhibited the favorable effect up to 50-55%, thereafter effective diffusivity decreased with a further increase in concentration.     

Comparative evaluation of the liver in dogs with a splenic mass by using ultrasonography and contrast-enhanced computed tomography

Evaluation of dogs with splenic masses to better educate owners as to the extent of the disease is a goal of many research studies. We compared the use of ultrasonography (US) and contrast-enhanced computed tomography (CT) to evaluate the accuracy of detecting hepatic neoplasia in dogs with splenic masses, independently, in series, or in parallel. No significant difference was found between US and CT. If the presence or absence of ascites, as detected with US, was used as a pretest probability of disease in our population, the positive predictive value increased to 94% if the tests were run in series, and the negative predictive value increased to 95% if the tests were run in parallel. The study showed that CT combined with US could be a valuable tool in evaluation of dogs with splenic masses.     

Effects of Saccharomyces cerevisiae on in vivo organic matter digestibility and milk yield in buffalo cows

The influence of a dietary supplementation with Saccharomyces cerevisiae (SC) during the first and the second phase of lactation on dry matter (DM) intake, organic matter digestibility, milk yield and quality and haematological profile was evaluated in buffalo cows. Lactating buffaloes (n = 190), 118.7 days in milk (DIM), were randomly divided into Group C (control, n = 95) and Group T (fed diet supplemented with 98 billion CFU of S. cerevisiae, n = 95). Eight buffaloes for each group (Groups T1 and C1), 85.4 DIM, were used to study the in vivo digestibility and the haematological profile. No differences were found for DM intake (16.5 kg·day^− 1) and haematological profile. The SC supplementation increased milk yield (7.9 ± 0.2 vs. 7.4 ± 0.2; P < 0.01) but did not affect milk fat and protein. SC supplementation increased OM digestibility, mainly, in the first phase of lactation (< 135 days), thus allowing a higher energy availability for milk yield and reduced fat mobilization.     

INTRAVENOUS ALFAXALONE ANAESTHESIA IN LEOPARD GECKOS (EUBLEPHARIS MACULARIUS)

Intravenous alfaxalone, administered at a dose of 5 mg/kg in the jugular vein, was evaluated in 20 leopard geckos (Eublepharis macularius) to ascertain its ability to provide anesthesia. The induction time, time to loss of mandibular tone, interval of deep anesthesia, and full recovery time were 27.5 ± 30.7 seconds (10 to 56 seconds), 1.3 ± 1.4 minutes (11 seconds to 4 minutes), 12.5 ± 2.2 minutes (11.11 to 15.39 minutes), and 18.8 ± 12.1 minutes (10.4 to 52.31 minutes), respectively. A significant reduction in heart rate (74 ± 12.9 beats/minute) was recorded between 2 and 24 minutes after alfaxalone administration. A significant decrease in respiratory rate (26.8 ± 10.1 breaths/minute) was recorded 2 minutes after alfaxalone administration, and respiratory rate remained lower than the basal rate (31.4 ± 3.1 breaths/minute) for 24 minutes but without statistical significance. The intravenous administration of alfaxalone in leopard geckos achieved a rapid onset of anesthesia and a suitable recovery time. Based on this investigation, an afaxalone dose of 5 mg/kg intravenously proved to be suitable for sedation before tracheal intubation. Moreover, the administration route via the jugular vein, was acceptable in leopard geckos; a species in which other venipuncture sites can be challenging or inaccessible.