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5-Aminolevulinic acid (ALA), as a novel plant growth regulator, is a critical precursor for the biosynthesis of porphyrin compounds in all organisms. Many studies have reported that exogenous ALA treatment could improve fruit sweetness. However, the mechanism by which ALA promotes the increase in sugar content in fruit remains unclear. In this study, we found that ALA significantly promoted sucrose accumulation and SPS (sucrose phosphate synthase) activity in peach fruit. At 14, 28, 42, 50 and 60 days after ALA treatment, sucrose content of fruit was increased by 23%, 43%, 37%, 40% and 16%, respectively, compared with control treatment, and SPS enzyme activity was increased by 21%, 28%, 47%, 37% and 29%, respectively. Correlation analysis showed that the sucrose content of peach fruit under ALA treatment was significantly positively correlated with SPS activity. Subsequently, bioinformatics was used to identify SPS gene family members in peach fruit, and it was found that there were four members of the PpSPS gene family, distributed on chromosomes 1, 7 and 8, named PpSPS1, PpSPS2, PpSPS3 and PpSPS4, respectively. The results of qRT-PCR showed that PpSPS2 and PpSPS3 were highly expressed in response to ALA during fruit development, and the expression of PpSPS2 was positively correlated with SPS activity and sucrose accumulation in peach fruit. The results of tobacco subcellular localization showed that PpSPS2 was mainly distributed in the cytoplasm and nucleus, while PpSPS3 was mainly distributed in the nucleus. The results of this study will lay the foundation for further study on the functions of PpSPS and the regulation of sugar metabolism during the development and ripening of peach fruit by ALA.
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Understanding bacteria and yeasts communities can reduce unpredictable changes of apple cider. In this study, apple juice inoculated with Saccharomyces cerevisiae WET 136 and fermented spontaneously were compared, the relationships of bacteria, yeasts, organic acids, and volatiles were analyzed. Results showed that microbial diversity affected the fermentation, organic acids and volatiles in apple ciders. In the first four spontaneous fermentation days, LAB (lactic acid bacteria) multiplied and reached 7.89 lg CFU/mL, and then triggered malolactic fermentation (MLF), leading to malic acid decreased by 3880.52 mg/L and lactic acid increased by 4787.55 mg/L. The citric, succinic and fumaric acids content was 2171.14, 701.51 and 8.06 mg/L lower than that in inoculated cider, respectively. Although the yeasts multiplied during spontaneous fermentation, it did not reach 7.50 lg CFU/mL until the 5th day, which led to a long lag period, as well as later and lower production of acetaldehyde and higher alcohols. The inoculated yeast inhibited LAB, acetic acid bacteria, Rahnella, and non-Saccharomyces. Yeasts were the key to produce citric acid, acetaldehyde and 3-methyl-1-butanol in apple cider; while bacteria were closely related to the formation of lactic acid, acetic acid and ethyl acetate. It suggested that low higher alcohols and acetaldehyde can be realized by selecting yeasts, and Leuconostoc pseudomesenteroides can work as candidate to reduce L-malic and citric acids in apple cider.
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Malus , Bebidas Alcoólicas/microbiologia , Leveduras , Álcoois , Fermentação , Saccharomyces cerevisiae , Bactérias , AcetaldeídoRESUMO
Chronic hepatitis B (CHB) remains a significant health challenge worldwide. The current treatments for CHB achieve less than 10% cure rates, majority of the patients are on therapy for life. Therefore, cure of CHB is a high unmet medical need. HBV surface antigen (HBsAg) loss and seroconversion are considered as the key for the cure. RG7834 is a novel, orally bioavailable small molecule reported to reduce HBV antigens. Based on RG7834 chemistry, we designed and discovered a series of dihydrobenzopyridooxazepine (DBP) series of HBV antigen inhibitors. Extensive SAR studies led us to GST-HG131 with excellent reduction of HBV antigens (both HBsAg and HBeAg) in vitro and in vivo. GST-HG131 improved safety in rat toxicology studies over RG7834. The promising inhibitory activity, together with animal safety enhancement, merited GST-HG131 progressed into clinical development in 2020 (NCT04499443).
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Hepatite B Crônica , Hepatite B , Animais , Ratos , Antígenos de Superfície , Antivirais/farmacologia , Antivirais/uso terapêutico , DNA Viral , Hepatite B/tratamento farmacológico , Antígenos E da Hepatite B/uso terapêutico , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica/tratamento farmacológicoRESUMO
BACKGROUND: Apple wine is a popular alcoholic beverage for its nutrition and fresh taste. However, the methanol existing in apple wine restricts its quality. Unfortunately, there are no methods to reduce the methanol content in fruit wine. To this end, bentonite (B), calcium chloride (CC) and their combination (B&CC) were added into apple juice in this study. The treated juice (0) and supernatant obtained by standing the juice at 25 °C for 24 h were fermented at 25 °C and 10 °C, respectively. RESULTS: Bentonite was an excellent methanol interrupter, a pectin retainer and a wine quality defender both at 25 and 10 °C. The lowest methanol content of 1.41 mg L-1 and higher pectin content of 84.74 mg L-1 were reached in the finished wine by B0 at 10 °C. Calcium chloride decreased pectin content, elevated methanol content and changed the profile of individual organic acids. In fact, the wine by B&CC0 at 25 °C showed dramatic changes in individual organic acids. The content of l-malic acid and succinic acid was only 2.22% and 6.29% of the control, respectively, while the lactic acid content was 17.72 times that of the control. CONCLUSIONS: It is suggested that B0 and fermented at 10 °C was the most effective way to decrease methanol content, retain pectin content and defend wine quality. © 2021 Society of Chemical Industry.
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Bebidas Alcoólicas/análise , Bentonita/química , Cloreto de Cálcio/química , Manipulação de Alimentos/métodos , Malus/química , Fermentação , Manipulação de Alimentos/instrumentação , Frutas/química , Metanol/química , Pectinas/químicaRESUMO
BACKGROUND: The carbohydrates in beer play an important role as they are essential for fermentation. Any change in their composition may influence the sensory characteristics of the beer and so their determination is of great interest. This study compares the carbohydrates in three types of commercial beer - barley malt beer, wheat beer, and barley malt beer with adjuncts - and examines their influence on beer quality, which is important for selecting raw ingredients and production conditions, and for quality control. RESULTS: Among the oligosaccharides in three types of beer, raffinose was the most, followed by maltotetraose, maltotriose and maltose. Monosaccharides were only present in small amounts. Dextrin, oligosaccharides with 2-6 polymerization degree and non-starch polysaccharides (NSP) make up 15.90-34.83%, 17.59-38.63%, and 2.33-7.47% of the total carbohydrates in beer, respectively. The dextrin content and NSP content were significantly (P < 0.05) different in wheat beer and barley malt beer, and their content was significantly (P < 0.01) correlated with the content of extracts in beer. Non-starch polysaccharide, dextrin, trisaccharide, and tetrasaccharide content significantly (P < 0.05) correlated with beer viscosity. These beer samples could be categorized clearly into three groups by principal component analysis. CONCLUSION: The oligosaccharides in beer reflect yeast utilization, depending on the type of beer. Dextrin, oligosaccharides with 2-4 polymerization, and NSP, were major carbohydrates in beer. Their composition and concentration influenced its characteristics and quality, and played an important role in the discrimination of different beer types. © 2020 Society of Chemical Industry.
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Cerveja/análise , Carboidratos/química , Hordeum/microbiologia , Triticum/microbiologia , Cerveja/economia , Metabolismo dos Carboidratos , Fermentação , Hordeum/metabolismo , Humanos , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Controle de Qualidade , Paladar , Triticum/metabolismo , Viscosidade , Leveduras/metabolismoRESUMO
This research was to explore the distribution and some molecular characterization of arabinoxylan in wheat beer (B), beer foam (BF) and defoamed beer (DB) because of the crucial influences of arabinoxylan on wheat beer and its foam. The purified arabinoxylan from B, BF, and DB were fractionated by ethanol of 50%, 67%, 75%, and 80%. The monosaccharide composition, substitution degree (Ara/Xyl ratio, A/X), and average degrees of polymerization (avDP) of arabinoxylan were investigated. Molecular weight and microstructure were also involved in this study by GPC-LLS and SEM, respectively. Under the same ethanol concentration, the arabinoxylan content in the BF was higher than the other two, respectively, and it was precipitated in BF fraction with 50% ethanol which accounted for 80.84% of the total polysaccharides. Meanwhile, the greatest substitution degree (A/X) and highest value of avDP of the arabinoxylan was found in all beer foam fractions regardless of the concentration of ethanol used. The average degrees of polymerization (avDP) of arabinoxylan displayed a significant difference (p < 0.05) among B, BF, and DB. Furthermore, arabinoxylan presented varied microstructure with irregular lamellas and spherical structures and the weight-average molecular weight (Mw) of arabinoxylan showed the lowest values in BF, while the largest values were shown in DB. Therefore, arabinoxylan was more accumulated in beer foam, especially in 50% ethanol, characterised by greater value of A/X and avDP, as well as lower Mw. It was suggested that the arabinoxylan played important roles in maintaining wheat beer foam characteristics.
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Cerveja/análise , Triticum/química , Xilanos/análise , Xilanos/química , Fenômenos Químicos , Peso Molecular , Polissacarídeos/análiseRESUMO
Hawthorn wine is rich in anthocyanins, polyphenols, flavonoids and other macromolecular substances, which results in difficulty to rapidly determine organic acids in the wine. An enzymatic method is accurate but expensive and not able to quantify all of the organic acids simultaneously. Therefore, in this study, two HPLC methods were applied to quantify the organic acids in the wine with the enzymatic method as a reference. Seven organic acids were found with the enzymatic method including citric, succinic, l-malic, acetic, lactic, pyruvic, and fumaric acids, in which citric and succinic acid accounted for more than 80% of the total acids. By an 87H column equipped with DAD (diode array) detector at 215 nm (HPLC method 1), only citric and lactic acids were quantified accurately and the elution period was shortened from 100 min to 20 min by removing the impurity in the sample with a LC-18 SPE(solid-phase extraction) tube. While citric, succinic, l-malic, acetic, pyruvic, and fumaric acids were quantified reliably by a dC18 column equipped with DAD detector at 210 nm (HPLC method 2), with the sample requires only dilution and filtration before injection. It was suggested that HPLC method 2 was an effective method to quantify the organic acids in hawthorn wine. The method provides a choice for accurate quantification of organic acids in hawthorn wine or other drinks, and would be helpful for controlling the quality of hawthorn wine.
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Ácidos Carboxílicos/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Crataegus/química , Ácido Cítrico/análise , Ácido Láctico/análise , Vinho/análiseRESUMO
In this work, the n-butanol extract from leaves of Lonicera japonica Thunb. (L. japonica) was reacted with DPPH and subjected to a HPLC analysis for the guided screening antioxidants (DPPH-HPLC experiments). Then, nine antioxidants, including flavonoid glycosides and caffeoylquinic acid derivatives, were isolated and purified from leaves of L. japonica using high speed counter-current chromatography (HSCCC) and prep-HPLC. The n-butanol extract was firstly isolated by HSCCC using methyl tert-butyl ether/n-butanol/acetonitrile/water (0.5% acetic acid) (2:2:1:5, v/v), yielding five fractions F1, F2 (rhoifolin), F3 (luteoloside), F4 and F5 (collected from the column after the separation). The sub-fractions F1, F4 and F5 were successfully separated by prep-HPLC. Finally, nine compounds, including chlorogenic acid (1), lonicerin (2), rutin (3), rhoifolin (4), luteoloside (5), 3,4-Odicaffeoylquinic acid (6), hyperoside (7), 3,5-O-dicaffeoylquinic acid (8), and 4,5-O-dicaffeoylquinic acid (9) were obtained, respectively, with the purities over 94% as determined by HPLC. The structures were identified by electrospray ionization mass spectrometry (ESI-MS), 1H- and 13C-NMR. Antioxidant activities were tested, and the isolated compounds showed strong antioxidant activities.
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Flavonoides/química , Flavonoides/isolamento & purificação , Glicosídeos/química , Glicosídeos/isolamento & purificação , Lonicera/química , Folhas de Planta/química , Ácido Quínico/análogos & derivados , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Flavonoides/farmacologia , Glicosídeos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Ácido Quínico/química , Ácido Quínico/isolamento & purificação , Ácido Quínico/farmacologia , Solventes , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Stable photoluminescence QD light-emitting diodes (QD-LEDs) were made based on hydrophilic CdTe quantum dots (QDs). A quantum dot-inorganic nanocomposite (hydrophilic CdTe QDs incorporating dehydrated silica gel) was prepared by two methods (rotary evaporation and freeze drying). Taking advantage of its viscosity, plasticity and transparency, dehydrated silica gel could be coated on the surface of ultraviolet (UV) light LEDs to make photoluminescence QD-LEDs. This new photoluminescence QD-LED, which is stable, environmentally non-toxic, easy to operate and low cost, could expand the applications of hydrophilic CdTe QDs in photoluminescence.
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Compostos de Cádmio/química , Luz , Pontos Quânticos/química , Dióxido de Silício/química , Telúrio/química , Géis , Interações Hidrofóbicas e Hidrofílicas , Luminescência , Processos FotoquímicosRESUMO
BACKGROUND: Arabinoxylans (AXs) are partially water-extractable polymers that cause problems of viscosity and filterability during beer brewing. This study investigated the effects of Kolbach index (KI) on water-extractable AXs (WEAXs). RESULTS: KI had positive correlations with extract (r = 0.845) and free amino nitrogen (FAN) (r = 0.958). The contents of malt WEAXs (WEAXsm), total AXs and wort AXs (WAXs) were 10.8-11.6 g kg⻹, 57.5-60.8 g kg⻹ and 137.5-140.5 mg per 100 mL respectively and the corresponding arabinose/xylose (A/X) ratios were 0.52-0.56, 0.55-0.62 and 0.48-0.50. The molecular weight (Mw) ranged from 4.92 × 104 to 6.93 × 104 Da for WEAXsm and from 1.24 × 104 to 2.90 × 104 Da for WAXs. KI had negative correlations with the average degree of polymerization (avDP) of malt (r = -0.877) and wort (r = -0.978). Wort viscosity showed a positive correlation with the Mw of WEAXsm (Mwm) (r = 0.821). CONCLUSION: Increasing KI can promote the degradation of the xylan backbone, while it cannot affect the branching of the polymer chain and the content and Mw of WEAXs.
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Manipulação de Alimentos , Qualidade dos Alimentos , Germinação , Sementes/química , Triticum/química , Xilanos/análise , Algoritmos , Arabinose/análise , Proteínas de Bactérias/metabolismo , Fenômenos Químicos , China , Glicosídeo Hidrolases/metabolismo , Hidrólise , Fenômenos Mecânicos , Peso Molecular , Polimerização , Sementes/crescimento & desenvolvimento , Solubilidade , Triticum/crescimento & desenvolvimento , Viscosidade , Xilanos/química , Xilanos/metabolismo , Xilose/análise , alfa-Amilases/metabolismoRESUMO
Intense debate persists about the timing and magnitude of the wet phases in the East Asia deserts since the late Pleistocene. Here we show reconstructions of the paleohydrology of the East Gobi Desert since the last interglacial using satellite images and digital elevation models (DEM) combined with detailed section analyses. Paleolakes with a total area of 15,500 km2 during Marine Isotope Stage 5 (MIS 5) were identified. This expanded lake system was likely coupled to an 800-1000 km northward expansion of the humid region in East China, associated with much warmer winters. Humid climate across the Gobi Desert during MIS 5 likely resulted in a dustier MIS 4 over East Asia and the North Pacific. A second wet period characterized by an expanded, albeit smaller, lake area is dated to the mid-Holocene. Our results suggest that the East Asian Summer Monsoon (EASM) might have been much weaker during MIS 3.
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Understanding pectin structure and pectinase activity was important to control methanol content in apple wine. Therefore, this study compared inoculated fermentation (I), spontaneous fermentation (S) and inoculated fermentation combined with CaCl2 treatment (I & CaCl2) to explore their differences in methanol production, pectin peak molecular weight (Mp), and the activities of pectin methyl esterase (PME), pectin lyase (PL) and polygalacturonase (PG). The results showed that the activities of PME, PL and PG were intensively inhibited during fermentation; however, they still retained 3.41-5.84% (PME), 9.46-17.71% (PL) and 9.17-10.31% (PG) of the initial activities after aging for 30 days. Therefore, the methanol content was increased in all three aged wines even aging at 4 °C. CaCl2 promoted the PME and PL activities, and thus accelerated the methanol production. Because the pectin with Mp 3.07 kDa was retained by CaCl2, the highest pectin content was found in wine I & CaCl2 (160.69 mg/L), which was 95.47 mg/L higher than that in wine I, and 107.03 mg/L higher than that in wine S. In group S, the long lag period allowed pectin to withstand the pectinases inherent in apple juice for a long time, which was conducive to the cleavage of pectin to Mp lower than 3 kDa continuously, its further degradation led to the lowest pectin content (53.65 mg/L) in wine. Hence, inhibiting the pectinases activities, or shortening the aging period would play an important role in decreasing the methanol content in apple wine.
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Malus , Vinho , Cloreto de Cálcio , Fermentação , Malus/metabolismo , Metanol/análise , Pectinas/metabolismo , Poligalacturonase/metabolismo , Vinho/análiseRESUMO
The development of high-performance electrocaloric (EC) materials is crucial for solid-state refrigeration applied in micro-electromechanical systems. Herein, a large room-temperature EC response is realized in (1 - x)(K0.49Na0.49Li0.02)(Nb0.8Ta0.2)O3-xCaZrO3 (KNLNT-xCZ) benefiting from a relaxor enhancement effect and multilayer ceramic construct. The relaxor enhancement effect is because the long-range order is broken by adding CaZrO3, which is in favor of enhancing the temperature change (ΔT) and broadening the temperature span (Tspan) at room temperature. A ΔT of 0.48 K in the KNLNT-12CZ ceramic is â¼5 times higher than that in the KNLNT-8CZ ceramic at 30 °C. KNLNT-12CZ also exhibits good temperature stability, and the Tspan is up to 65 K. In addition, the multilayer ceramic construct improves the breakdown electric field (Eb) through diminishing defects, leading to a booming ΔT of 3.2 K at 30 °C under 250 kV cm-1 via a direct measurement. The work proposes an avenue for developing high-performance EC materials with a large EC response and broad Tspan in solid-state refrigeration.
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From November 1,2018 to January 31,2019 (OP2018-2019) and from November 1,2019 to January 20, 2020 (OP2019-2020), PM1 measurement was conducted daily for two consecutive years. The concentration of trace elements in the atmospheric PM1 in Qingdao in autumn and winter was analyzed. The observation period was divided into four air quality levels (Level â , Level â ¡, Level â ¢, and Level â £), and the characteristics and sources of the concentration of trace elements in PM1 were analyzed. The non-carcinogenic risks (Zn, Pb, Mn, Cu, and V) and carcinogenic risks (As, Cr, Ni, Cd, and Co) of different people with different air quality levels were evaluated. The results showed that the changes in total metal element concentrations were associated with changes in Ca, K, and Al concentrations at different air quality classes during OP2019-2020 compared to those during OP2018-2019 and were more influenced by dust and biomass combustion sources. Compared with that during OP2018-2019, the V concentration in different air quality levels (Level â , Level â ¡, Level â ¢, and Level â £) during OP2019-2020 decreased by 19.0%, 60.5%, 82.7%, and 77.5%, respectively. This was presumed to be related to the implementation of the Domestic Emission Control Area (DECA) policy for ships, which led to the significant reduction in V concentration due to the change in fuel quality of ships in the waters around Qingdao. The results of the enrichment factor, the ratio method, and the backward trajectory of airflow further indicated that the changes in V concentrations were mainly influenced by the DECA policy. However, after the implementation of the DECA, the V/Ni value as a limit for judging the influence of ship sources in the area required further exploration. The health risk assessment results showed that the risk factor of Mn ranged from 0.07 to 1.22 during OP2018-2019 and OP2019-2020. It was recommended to strengthen the management and control of Mn-containing pollution sources. The lifetime carcinogenic risk (ILCR) value of As and Cd under different air qualities during OP2018-2019 and OP2019-2020 was lower than 10-4 but higher than 10-6, indicating that there was a carcinogenic probability, although it was still at an acceptable level. During OP2018-2019, when the air quality was â £, the ILCR value of Cr was higher than 10-4, and there was a risk of cancer.
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Poluentes Atmosféricos , Oligoelementos , Poluentes Atmosféricos/análise , Cádmio , Carcinógenos , Monitoramento Ambiental , Humanos , Medição de Risco , Oligoelementos/análiseRESUMO
The volatile organic compounds emitted by plants significantly impact the atmospheric environment. The impacts of drought stress on the biogenic volatile organic compound (BVOC) emissions of plants are still under debate. In this study, the effects of two drought-rehydration cycle groups with different durations on isoprene emissions from Populus nigra (black poplar) seedlings were studied. The P. nigra seedlings were placed in a chamber that controlled the soil water content, radiation, and temperature. The daily emissions of isoprene and physiological parameters were measured. The emission rates of isoprene (Fiso) reached the maximum on the third day (D3), increasing by 58.0% and 64.2% compared with the controlled groups, respectively, and then Fiso significantly decreased. Photosynthesis decreased by 34.2% and 21.6% in D3 in the first and second groups, respectively. After rehydration, Fiso and photosynthesis recovered fully in two groups. However, Fiso showed distinct inconsistencies in two groups, and the recovery rates of Fiso in the second drought group were slower than the recovery rates of Fiso in the first groups. The response of BVOC emissions during the drought-rehydration cycle was classified into three phases, including stimulated, inhibited, and restored after rehydration. The emission pattern of isoprene indicated that isoprene played an important role in the response of plants to drought stress. A drought-rehydration model was constructed, which indicated the regularity of BVOC emissions in the drought-rehydration cycle. BVOC emissions were extremely sensitive to drought, especially during droughts of short duration. Parameters in computational models related to BVOC emissions of plants under drought stress should be continuously improved.
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Populus , Compostos Orgânicos Voláteis , Populus/fisiologia , Secas , Plântula , Fotossíntese , Plantas , Hidratação , Folhas de PlantaRESUMO
Atmospheric sub-micrometer particles (PM1, particles with an aerodynamic diameter ≤ 1.0 µm) monitoring in Qingdao, a coastal city in Northern China, was conducted for two consecutive years from November 1, 2018 to January 31, 2019 (hereafter referred to as OP2018-2019) and from October 28, 2019 to January 20, 2020 (hereafter referred to as OP2019-2020). The results showed that compared with OP2018-2019, the concentrations of V, Ni, As, Pb, and Cd in PM1 in OP2019-2020 decreased by 61.9%, 31.4%, 49.2%, 25.4%, and 27.1%, respectively. For the indicators of ship emission sources, a significant reduction in V (73.3%) and Ni (22.1%) concentrations were observed after the implementation of the updated Domestic Emission Control Area (DECA 2.0) policy for ships since January 1, 2019 proposed by the Ministry of Transportation. This result demonstrated that the implementation of the DECA 2.0 policy had a significant effect on reducing ship emissions. The Field Emission Scanning Electron Microscope analysis identified the impact of ship emission sources, while the inconsistent distribution of V and Ni revealed other potential sources of Ni. The V/Ni ratios during the pre-policy and post-policy periods decreased by 40.7%. Along with the further implementation of the domestic coastal ship pollution control zone policy, V/Ni ratio should be cautiously used as a parameter for ship emission sources. The positive matrix factorization method identified five source factors: coal combustion/biomass burning (47.8%), crustal sources (21.2%), vehicle exhaust/road dust (15.1%), industrial emissions (11.1%), and ship emissions (4.9%). The contribution rates of ship emission sources before and after the DECA 2.0 policy were analyzed and found to be 5.6% and 3.4%. The potential source contribution factor analysis of As showed that the potential emission source areas were significantly reduced in OP2019-2020, which might be related to the coal fired cleanup operations conducted in Beijing-Tianjin-Hebei and surrounding areas.
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Poluentes Atmosféricos , Oligoelementos , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano , Oligoelementos/análise , Emissões de Veículos/análiseRESUMO
On-skin devices that show both high performance and imperceptibility are desired for physiological information detection, individual protection, and bioenergy conversion with minimal sensory interference. Herein, versatile electrospun micropyramid arrays (EMPAs) combined with ultrathin, ultralight, gas-permeable structures are developed through a self-assembly technology based on wet heterostructured electrified jets to endow various on-skin devices with both superior performance and imperceptibility. The designable self-assembly allows structural and material optimization of EMPAs for on-skin devices applied in daytime radiative cooling, pressure sensing, and bioenergy harvesting. A temperature drop of ~4 °C is obtained via an EMPA-based radiative cooling fabric under a solar intensity of 1 kW m-2. Moreover, detection of an ultraweak fingertip pulse for health diagnosis during monitoring of natural finger manipulation over a wide frequency range is realized by an EMPA piezocapacitive-triboelectric hybrid sensor, which has high sensitivity (19 kPa-1), ultralow detection limit (0.05 Pa), and ultrafast response (≤0.8 ms). Additionally, EMPA nanogenerators with high triboelectric and piezoelectric outputs achieve reliable biomechanical energy harvesting. The flexible self-assembly of EMPAs exhibits immense potential in superb individual healthcare and excellent human-machine interaction in an interference-free and comfortable manner.
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Dispositivos Eletrônicos Vestíveis , Dedos , Humanos , Pele/química , TêxteisRESUMO
To establish a rapid method for analysis of gingerol-related compounds in fresh ginger by using high performance liquid chromatography coupled with electron spray ionization-quadrupole-time of flight mass/mass spectrometry (HPLC-ESI-Q-TOF-MS/ MS). The gingerol-related compounds in fresh ginger was separated by an Inertsil ODS-SP column (4.6 mm x 250 mm, 5 microm) using a binary eluent under gradient conditions. The analytes were detected by ESI-Q-TOF-MS/MS in positive ion mode to obtain MS and MS/MS spectra and to extract molecular weights. From the MS data, the accurate molecular weights of gingerol-related compounds were obtained, and from the MS/MS data, the (+) ESI-Q-TOF-MS/MS fragments were obtained. 25 gingerol-related compounds were identified from fresh ginger by attentive studying on the mass spectra of compounds and comparing with reference data reported in the literature, respectively. This method was certified to be accurate and reliable and can be used for the rapid analysis of gingerol-related compounds in fresh ginger.
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Catecóis/análise , Cromatografia Líquida de Alta Pressão/métodos , Álcoois Graxos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Zingiber officinale/químicaRESUMO
Non-starch polysaccharides (NSPs) in beers attract extensive attention due to their health benefits. The aim of this work was to investigate and compare NSPs including arabinoxylan, arabinogalactan, ß-glucans, and mannose polymers in wheat and barley malt beers as well as the influence on its quality. NSPs in wheat beers (1953-2923 mg/L) were higher than that in barley malt beers (1442-1756 mg/L). Arabinoxylan was the most abundant followed by arabinogalactan. In contrast to barley malt beers, wheat beers contained more mannose polymers (130-182 mg/L) than ß-glucan (26-99 mg/L), indicating that more arabinoxylan, arabinogalactan, and mannose polymers came from wheat malt. The substitution degree of arabinoxylan in wheat beers (0.57-0.66) was lower than that in barley malt beers (0.68-0.72), while the degree of polymerization (38-83) was higher (p < 0.05) than that in barley malt beers (38-48), indicating different structures of arabinoxylan derived from barley malt and wheat malt. NSPs, especially arabinoxylan content, positively correlated (p < 0.01) with real extract and viscosity of beers. Furthermore, wheat and barley malt beers were well separated in groups by principal component analysis.
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The development of natural and biodegradable polymer nanoparticles as Pickering emulsion stabilizers has attracted increasing interest. In this study, antioxidative pectin from hawthorn wine pomace (HP) was first produced. HP and zein-nanoparticles (ZPs) were used to fabricate zein-HP composite nanoparticles (ZHPs) via hydrogen bonding and electrostatic interaction. The ZHP composite at the HP-ZP ratio of 1:1 (w/w) exhibited near-neutral wettability (92.9o ± 1.01), thereby being used for stabilizing Pickering emulsion (ZHPEs). CLSM and cryo-SEM showed the anchoring of ZHPs onto the surface of oil droplets and the gel-like network structure in the continuous-phase. ZHPEs at 0.5-0.7 (v/v) oil fractions were pseudoplastic fluids with elastic-solid characteristics. ZHPEs with 0.6 and 0.7 (v/v) oil fractions showed excellent thermal stability 20-60 °C. The antioxidant capacity of HP helped protect the Pickering emulsion against its lipid oxidation. Therefore, antioxidative polysaccharides could stabilize Pickering emulsions as particle shell-materials while offering protection on lipid components against oxidation. This study has demonstrated the sustainable utilization of food waste for producing value-added products.