Carotenoid, chlorophyll, and chlorophyll-derived compounds in grapes and port wines

Carotenoids and chlorophyll-derived compounds in grapes and Port wines were investigated by HPLC-DAD and HPLC-DAD-MS (ESP+) analysis. A total of 13 carotenoid and chlorophyll-derived compounds are formally reported in grapes, 3 are identified for the first time, pheophytins a and b and (13Z)-beta-carotene, and 3 others remain unknown. In Port wines 19 compounds with carotenoid or chlorophyll-like structures are present, 8 still unidentified. The young wines showed higher total carotenoid content and chlorophyll-like compounds compared to aged Ports, with lutein and beta-carotene as major carotenoids. Among samples analyzed of monovarietal Vitis vinifera L. cultivar wines produced with the five most important Douro varieties, Tinta Roriz contained the highest levels of carotenoids and Touriga Franca the lowest. The forced-aging study indicated that lutein was more sensitive to temperature than beta-carotene. Additionally, aged wines showed higher ratios of beta-carotene/lutein concentrations compared to new Ports. Rates of degradation of chlorophyll derivative compounds were higher than those for carotene and lutein.     

DRIS norms and limiting nutrients in banana cultivation in the South of Ecuador

Abstract

Foliar analysis is an effective method to diagnose the nutritional status of plants. However, the mineral concentration in foliar tissue has traditionally been evaluated by assessing the activity of each element, without considering the interactions between them. To address this, dual interactions were calculated using the Diagnosis and Recommendation Integrated System (DRIS) to identify which crop nutrients are most influential in nutrient imbalances and which are the most limiting nutrients for the nutritional status of banana crops in Ecuador. To achieve this, a regional survey of the nutritional status and its productivity levels was conducted for 188 different sites during the crop season in 2017–2018, involving banana cultivars ‘Vallery’ and ‘Williams’, from the Cavendish subgroup. The DRIS calculation method was combined with Beaufils and Jones functions. From the initial 188 foliar samples, 83 samples (representing 44% of the population) were considered to represent the high-yield reference population, with yields of 38–60 t ha^?1. The DRIS method defined the mean nutritional balance index, which was not found to be statistically correlated (p?>?0.05) with productivity, revealing that there was no significant association with the nutritional status of the plants. Specific DRIS norms were obtained and indicated that deficiencies in K, N, Ca, and Fe, and excesses in Mn, B, Cl, Zn, S, Cu, and Mg were the most limiting nutrients for banana cultivars in the south of Ecuador.     

Water activity effects on geranyl acetate synthesis catalyzed by novozym in supercritical ethane and in supercritical carbon dioxide

The esterification reaction of geraniol with acetic acid catalyzed by Novozym was studied in supercritical ethane (sc-ethane) and in supercritical carbon dioxide (sc-CO(2)). Water activity (a(W)) had a very strong effect on enzyme activity, with reaction rates increasing up to a(W) = 0.25 and then decreasing for higher a(W). Salt hydrate pairs could not prevent changes in a(W) during the course of reaction but were able to control a(W) to some extent and had a beneficial effect on both initial rates of esterification and conversion in sc-ethane. The enzyme was more active in sc-ethane than in sc-CO(2), confirming the deleterious effect of the latter already observed with some enzymes. Temperatures between 40 and 60 degrees C did not have a strong effect on initial rates of esterification, although reaction progress declined considerably in that temperature range. For the mixture of 50 mM acetic acid plus 200 mM geraniol, 100% conversion was achieved at a reaction time of 10 h at 40 degrees C, 100 bar, an a(W) of incubation of 0.25, and a Novozym concentration of 0.55 mg cm(-)(3) in sc-ethane. Conversion was below 50% in sc-CO(2) at otherwise identical conditions. With an equimolar mixture of the two substrates (100 mM), 98% conversion was reached at 10 h of reaction in sc-ethane (73% conversion in sc-CO(2)).     

Can Non-fumigant Nematicides Be an Alternative to Fumigation on Carrot Fields?

ABSTRACT

Root-knot nematodes (RKN; Meloidogyne spp.) cause enormous yield reductions in vegetable crops. While nematicides are the most effective method for controlling RKN in carrot (Dacatus carota), the efficacy of non-fumigant nematicides, compared to fumigants, is still not fully understood. The objective of this study was to evaluate the effect of 1,3-dichloropropene, a fumigant nematicide, and fluensulfone, a non-fumigant nematicide, on RKN control and yield of fresh market and processing carrot. Field experiments were conducted in a commercial farm in Lenox, GA. A randomized complete block design (r = 4) was used in a factorial arrangement of 3 nematicide treatments and 2 carrot cultivars. Nematicide treatments were the application of 1,3-dichloropropene, fluensulfone, and untreated control. Carrot cultivars were Baltimore (fresh marketing) and Belgrado (processing). In general, RKN population was low early season, averaging 0.8 RKN 100 cm^?3 of soil. RKN populations increased with crop development and there were significant differences among nematicide treatments. At harvest, RKN populations were lower for fluensulfone (1.1 RKN 100 cm^?3 of soil) and 1,3-dichloropropene (3.2 RKN 100 cm^?3 of soil) compared to Control (26.4 RKN 100 cm^?3 of soil); however, fluensulfone (91,278 kg ha^?1) had higher yield than 1,3-dichloropropene (64,154 kg ha^?1) and Control (61,908 kg ha^?1). Carrot cultivars were similar for RKN population and yield. Overall, the non-fumigant nematicide was more beneficial for carrot production than the fumigant nematicide.     

Changes in photosynthesis and antioxidant metabolism of cotton (Gossypium hirsutum L.) plants in response to manganese stress

ABSTRACT

This study aimed to assess the physiological and biochemical responses of cotton plants to manganese (Mn²⁺) nutrition. Four cotton genotypes (G1 – TMG 47; G2 – FM 975 WS; G3 – TMG 11 WS and G4 – IMA 8405 GLT) were grown in nutrient solution under two Mn²⁺ concentrations (2 and 200 µmol L^?1) for 10 days. No visible symptoms of Mn²⁺ toxicity were observed in the genotypes tested. All genotypes showed a marked increase in leaf chlorophylls, pheophytins, carotenoids, sucrose and total sugars concentration in response to high Mn²⁺ in a nutrient solution. However, the net photosynthetic rate, stomatal conductance, internal carbon dioxide concentration and transpiration decreased in genotypes G1 and G2 growing under 200 µmol L^?1. Antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) activities increased in genotypes G1, G3 and G4. Cotton genotypes showed an increased leaf antioxidant and sugar metabolism as a possible strategy to mitigate oxidative stress. The decrease in the net photosynthetic rate and stomatal conductance; the increased antioxidant enzymes activities (SOD, APX and GR); and the increase in leaf sucrose and total sugar concentration were the main physiological and biochemical responses in cotton plants to Mn²⁺ stress.     

Comparative study of ovatifolin antioxidant and growth inhibition activities

A comparative study on the effect of arturin (1), ovatifolin (3), deacetylovatifolin (5), and their 1-acetoxyarturin (2), 8-acetoxyovatifolin (4), 1,10-epoxyovatifolin (6), and 11,13-dihydroovatifolin (7) derivatives, isolated from Podanthus ovatifolius and Podanthus mitiqui, on the seedling growth, germination, and respiration of several monocot and dicot weedy target species was carried out. In addition to the inhibitory activity on the bleaching of crocin induced by alkoxyl radicals, these compounds also displayed scavenging properties toward DPPH in TLC autographic and spectrophotometric assays. The results indicate that ovatifolin (3), deacetylovatifolin (5), epoxyovatifolin (6), dihydroovatifolin (7), and the CH(2)Cl(2) extract interfere with pre-emergence of seedlings at the level of respiration. These compounds appear to have selective effects on the radicle and shoot growth of Physalis ixocarpa and Trifolium pratense. Their allelopathic effects are comparable to those of parthenolide, a know natural growth inhibitor.     

Free amino acid composition of quince (Cydonia oblonga Miller) fruit (pulp and peel) and jam

Twenty-one free amino acids present in several samples of quince fruit (pulp and peel) and quince jam (homemade and industrially manufactured) were analyzed by GC/FID. The analyses showed some differences between quince pulps and peels. Generally, the highest content in total free amino acids and in glycine was found in peels. As a general rule, the three major free amino acids detected in pulps were aspartic acid, asparagine, and hydroxyproline. For quince peels, usually, the three most abundant amino acids were glycine, aspartic acid, and asparagine. Similarly, for quince jams the most important free amino acids were aspartic acid, asparagine, and glycine or hydroxyproline. This study suggests that the free amino acid analysis can be useful for the evaluation of quince jam authenticity. It seems that glycine percentage can be used for the detection of quince peel addition while high alanine content can be related to pear addition.     

Comprehensive study on the chemical structure of dioxane lignin from plantation Eucalyptus globulus wood

Results of a comprehensive study on the chemical structure of lignin from plantation Eucalyptus globulus Labill are presented. Lignin has been isolated by a modified mild acidolysis method and thoroughly characterized by functional group analysis, by a series of degradation techniques (nitrobenzene oxidation, permanganate oxidation, thioacidolysis, and Py-GC-MS), and (1)H and (13)C NMR spectroscopy. Plantation Eucalyptus globulus lignin was found to be of the S/G type with an extremely high proportion of syringyl (S) units (82-86%) and a minor proportion of p-hydrophenyl propane (H) units (roughly 2-3 mol %). Unknown C-6 substituted and 4-O-5' type syringyl substructures represent about 65% of lignin "condensed" structures. Eucalypt lignin showed high abundance of beta-O-4 (0.56/C(6)) structures and units linked by alpha-O-4 bonds (0.23/C(6)). The proportion of phenylcoumaran structures was relatively low (0.03/C(6)). Different kinds of beta-beta substructures (pino-/syringaresinol and isotaxiresinol types) in a total amount of 0.13/C(6) were detected. ESI-MS analysis revealed a wide molecular weight distribution of lignin with the center of gravity of mass distribution around 2500 u.     

Profiling essential genes in human mammary cells by multiplex RNAi screening

By virtue of their accumulated genetic alterations, tumor cells may acquire vulnerabilities that create opportunities for therapeutic intervention. We have devised a massively parallel strategy for screening short hairpin RNA (shRNA) collections for stable loss-of-function phenotypes. We assayed from 6000 to 20,000 shRNAs simultaneously to identify genes important for the proliferation and survival of five cell lines derived from human mammary tissue. Lethal shRNAs common to these cell lines targeted many known cell-cycle regulatory networks. Cell line-specific sensitivities to suppression of protein complexes and biological pathways also emerged, and these could be validated by RNA interference (RNAi) and pharmacologically. These studies establish a practical platform for genome-scale screening of complex phenotypes in mammalian cells and demonstrate that RNAi can be used to expose genotype-specific sensitivities.