Dynamic Changes in Anthocyanin Accumulation and Cellular Antioxidant Activities in Two Varieties of Grape Berries during Fruit Maturation under Different Climates

As popularly consumed fruit berries, grapes are widely planted and processed into products, such as raisins and wine. In order to identify the influences of different climatic conditions on grape coloring and quality formation, we selected two common varieties of grape berries, ‘Red Globe’ and ‘Xin Yu’, for investigation. Grapes were separately grown in different climates, such as a temperate continental arid climate and a temperate continental desert climate, in Urumqi and Turpan, China, for five developmental stages. As measured, the average daily temperature and light intensity were lower in Urumqi. Urumqi grape berries had a lower brightness value (L*) and a higher red-green value (a*) when compared to Turpan’s. A RT-qPCR analysis revealed higher transcriptions of key genes related to anthocyanin biosynthesis in Urumqi grape berries, which was consistent with the more abundant phenolic substances, especially anthocyanins. The maximum antioxidant activity in vitro and cellular antioxidant activity of grape berries were also observed in Urumqi grape berries. These findings enclosed the influence of climate on anthocyanin accumulation and the antioxidant capacity of grapes, which might enlarge our knowledge on the quality formation of grape berries and might also be helpful for cultivating grapes with higher nutritional value.

Quality of triticale cupcakes enriched with pumpkin paste

Aims. To study the quality formation of a cupcake made from triticale flour enriched with pumpkin paste. Methods. Laboratory, mathematical and statistical, physicochemical. Results. The article presents the study results of the quality formation of triticale cupcakes (baking, shrinkage, moisute, volume, porosity), enriched with pumpkin paste. It is established that the quality of triticale cupcakes varies significantly from the pumpkin paste content. As a result of research, it was found that the baking rate of cupcakes varied depending on the pumpkin paste content and was 2.77–3.90 %. This indicator is the lowest in the control variant - without pumpkin paste addition – 2.77 %. Variants with the addition of 5, 15, 35 and 40% of pumpkin paste were characterized by high rates, where the baking rate was 3.72, 3.8, 3.85 and 3.9, respectively. In other experiment variants it was at the level of 3.14–3.63 %. Shrinkage of triticale flour cupcakes enriched with pumpkin paste did not change significantly and amounted to 1.0–1.4 %. It was found that with pumpkin paste addition, the moisture of the cupcakes increased from 21.4 with 5% of pumpkin paste to 36.1 % with 50 %. The highest moisture was characterized by variants with a content of 40, 45 and 50 % of pumpkin paste, respectively, 33.4, 33.2 and 36.1 %. When pumpkin paste is added to the dough, cupcake volume increases from 5 to 50 %. It is obvious that the absence of pumpkin gluten in the paste is the main reason for intensity decrease in the processes of dough leavening and increasing its density. Therefore, with pumpkin paste addition, the porosity of baked goods was not developed, the pores are small and thick-walled. Thus, cupcake porosity was 28.4–55.6 %. This figure was the highest with the addition of 5 % of pumpkin paste – 55.6 %, which is 5.4 % more than control. As the amount of pumpkin paste increased, the cupcake porosity also decreased. Conclusions. In the technology of triticale cupcakes, it is optimal to add 25–30 % of pumpkin paste by dough weight.

Effects of High Temperature on Rice Grain Development and Quality Formation Based on Proteomics Comparative Analysis Under Field Warming

With the intensification of global warming, rice production is facing new challenges. Field evidence indicates that elevated temperature during rice grain-filling leads to the further deterioration of grain quality. In order to clarify the potential regulatory mechanism of elevated temperature on the formation of rice quality, the DIA mass spectrometry method under the background of field warming was conducted to investigate the regulatory effects of high temperature on grain development and material accumulation pathways. The results showed that a total of 840 differentially expressed proteins were identified during the grain-filling process under elevated temperature. These differentially expressed proteins participated in carbon metabolism, amino acid biosynthesis, signal transduction, protein synthesis, and alternately affected the material accumulation of rice grains. The significant up-regulation of PPROL 14E, PSB28, granule-bound starch synthase I, and the significant down-regulation of 26.7 kDa heat shock protein would lead to the component difference in grain starch and storage proteins, and that could be responsible for the degradation of rice quality under elevated temperature. Results suggested that proteins specifically expressed under elevated temperature could be the key candidates for elucidating the potential regulatory mechanism of warming on rice development and quality formation. In-depth study on the metabolism of storage compounds would be contributed in further proposing high-quality cultivation control measures suitable for climate warming.

Amino acid transporter (AAT) gene family in foxtail millet (Setaria italica L.): widespread family expansion, functional differentiation, roles in quality formation and response to abiotic stresses

Background Amino acid transporters (AATs) plays an essential roles in growth and development of plants, including amino acids long-range transport, seed germination, quality formation, responsiveness to pathogenic bacteria and abiotic stress by modulating the transmembrane transfer of amino acids. In this study, we performed a genome-wide screening to analyze the AAT genes in foxtail millet (Setaria italica L.), especially those associated with quality formation and abiotic stresses response. Results A total number of 94 AAT genes were identified and divided into 12 subfamilies by their sequence characteristics and phylogenetic relationship. A large number (58/94, 62%) of AAT genes in foxtail millet were expanded via gene duplication, involving 13 tandem and 12 segmental duplication events. Tandemly duplicated genes had a significant impact on their functional differentiation via sequence variation, structural variation and expression variation. Further comparison in multiple species showed that in addition to paralogous genes, the expression variations of the orthologous AAT genes also contributed to their functional differentiation. The transcriptomic comparison of two millet cultivars verified the direct contribution of the AAT genes such as SiAAP1, SiAAP8, and SiAUX2 in the formation of grain quality. In addition, the qRT-PCR analysis suggested that several AAT genes continuously responded to diverse abiotic stresses, such as SiATLb1, SiANT1. Finally, combined with the previous studies and analysis on sequence characteristics and expression patterns of AAT genes, the possible functions of the foxtail millet AAT genes were predicted. Conclusion This study for the first time reported the evolutionary features, functional differentiation, roles in the quality formation and response to abiotic stresses of foxtail millet AAT gene family, thus providing a framework for further functional analysis of SiAAT genes, and also contributing to the applications of AAT genes in improving the quality and resistance to abiotic stresses of foxtail millet, and other cereal crops.

Effect of drought on photosynthesis, total antioxidant capacity, bioactive component accumulation, and the transcriptome of Atractylodes lancea

Background Atractylodes lancea (Thunb.) DC, a medicinal herb belonging to the Asteraceae family, often faces severe drought stress during its growth. Until now, there has been no research on the effect of drought stress on the quality formation of A. lancea. Therefore, the present study aimed to study the effects of drought stress on A. lancea through physical and chemical analysis, and to reveal the related molecular mechanisms via transcriptome analysis. Results The photosynthesis was markedly inhibited under drought stress. There were alterations to photosynthetic parameters (Pn, Gs, Ci) and chlorophyll fluorescence (Fv/Fm, NPQ), and the chlorophyll content decreased. Twenty genes encoding important regulatory enzymes in light and dark reactions, including the Rubisco gene of the Calvin cycle, were significantly downregulated. After exposure to drought stress for more than 4 days, the activities of four antioxidative enzymes (SOD, POD CAT and APX) began to decrease and continued to decrease with longer stress exposure. Meanwhile, most of the genes encoding antioxidative enzymes were downregulated significantly. The downregulation of 21 genes related to the respiratory electron transport chain indicated that the blocked electron transfer accelerated excessive ROS. The MDA content was significantly elevated. The above data showed that 15 days of drought stress caused serious oxidative damage to A. lancea. Drought stress not only reduced the size and dry weight of A. lancea, but also lowered the amount of total volatile oil and the content of the main bioactive components. The total volatile oil and atractylodin content decreased slightly, whereas the content of atractylon and β-eudesmol decreased significantly. Moreover, ten significantly downregulated genes encoding sesquiterpene synthase were mainly expressed in rhizomes. Conclusions After exposed to drought stress, the process of assimilation was affected by the destruction of photosynthesis; stress tolerance was impaired because of the inhibition of the antioxidative enzyme system; and bioactive component biosynthesis was hindered by the downregulation of sesquiterpene synthase-related gene expression. All these had negative impacts on the quality formation of A. lancea under drought stress.

Hydrological paradoxes of phytoplankton distribution in the Novosibirsk reservoir

<p>The ecosystem of the Novosibirsk reservoir - the largest in West Siberia, is the object of this research aimed at studying the mechanisms of water quality formation, which differs in various parts of the reservoir. The research novelty is in simulation of ecological processes occurring in various water areas and in the reservoir as a whole through reproduction of biogeochemical cycles of limiting elements.</p><p>The city of Novosibirsk is the administrative center of the Siberian Federal District, which occupies more than 25% of the territory of Russia. The Novosibirsk reservoir is major source of water supply in Novosibirsk. Still, some features of its water quality formation have been poorly explained.</p><p>For instance, it is believed that relatively shallow and low flow sites of water bodies are most susceptible to eutrophication. In such places, water warms up better and phytoplankton biomass is much higher. In the central part of the reservoir, depth at the left bank is much less than that at the right one, through which most riverbed flow passes (from the Ob river to the dam). However, according to long-term observations, in every August, phytoplankton biomass at the right bank is several times higher than at the left one.</p><p>One more paradox may be considered. Phytoplankton biomass in the surface water layer during the open water period is usually much abundant than at depth characterized by worse penetration of solar radiation. Nevertheless, in the studied period (August 1981), we observed the inverse ratio when phytoplankton biomass at depth significantly exceeded that in the surface layer.</p><p>For better understanding these phenomenon, a comparative assessment of mechanisms of in-water processes was performed through applying 3D simulation methods and reproducing the cycles of biogenic elements transformation.</p><p>Due to simulation and its results analysis, we revealed the following:</p><ul><li>the peculiarities of water exchange influenced by stable wind currents in August-September bring to phytoplankton biomass excess at depth near the right bank in contrast to relatively shallow water area near the left one of the Novosibirsk reservoir;</li> <li>“locking” by thermocline and subsequent fluctuations in vertical water exchange lead to abundant phytoplankton biomass in the water column as compared to the surface layer near the dam.</li> </ul><p>Thus, simulation demonstrates that the above mentioned paradoxes of phytoplankton development in the Novosibirsk reservoir are induced by specific hydrothermal processes.</p><p>The study importance goes beyond only giving insight into the causes of interesting natural phenomena. A detailed analysis of simulation results enables to explain nontrivial features of spatially distributed dynamic ecological processes. The possibilities of forecasting the reservoir ecosystem response to changes in different factors associated with varying external effects have been expanded. To mitigate negative impacts of eutrophication, you can change flow patterns at appropriate times, for example, by selecting a suitable operating mode of a hydro-station. The study demonstrates that contaminated water outflow from some water areas may be executed by directional energy use of natural phenomena.</p>