Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 76
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38639142

RESUMO

The high performance of a multistage thermoelectric cooler (multi-TEC) used in a wide low-temperature range depends on the optimized thermoelectric (TE) performance of materials during the corresponding working temperature range for each stage. Despite decades of research on the commercial TE materials of Bi2Te3, the main research is still focused on temperatures above 300 K, lacking suitable hierarchical low-temperature n-Bi2Te3 for multistage TEC. In this work, we systematically investigated the influence of doping concentration and matrix material compositions on the TE performance of n-Bi2Te3 below room temperature by the high-energy ball milling and hot deformation. Consequently, two hierarchical n-Bi2Te3 materials with excellent mechanical properties working below 248 and around 298 K, respectively, have been screened out. The Bi2Te2.7Se0.3 + 0.03 wt % TeI4 can be adopted in a low-temperature range that exhibits the high average figure of merit (zTave) of 0.61 within 173-248 K. Meanwhile, the Bi2Te2.7Se0.3 + 0.05 wt % TeI4 sample displays a competitive zTave of 0.85 within 248-298 K, which can be applied above 248 K. The research of hierarchical TE materials provides valuable insights into the high-performance design of multistage TE cooling devices.

2.
J Agric Food Chem ; 72(10): 5089-5106, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38416110

RESUMO

Polyamines and their derivatives are ubiquitously present in free or conjugated forms in various foods from animal, plant, and microbial origins. The current knowledge of free polyamines in foods and their contents is readily available; furthermore, conjugated polyamines generate considerable recent research interest due to their potential health benefits. The structural diversity of conjugated polyamines results in challenging their qualitative and quantitative analysis in food. Herein, we review and summarize the knowledge published on polyamines and their derivatives in foods, including their identification, sources, quantities, and health benefits. Particularly, facing the inherent challenges of isomer identification in conjugated polyamines, this paper provides a comprehensive overview of conjugated polyamines' structural characteristics, including the cleavage patterns and characteristic ion fragments of MS/MS for isomer identification. Free polyamines are present in all types of food, while conjugated polyamines are limited to plant-derived foods. Spermidine is renowned for antiaging properties, acclaimed as antiaging vitamins. Conjugated polyamines highlight their anti-inflammatory properties and have emerged as the mainstream drugs for antiprostatitis. This paper will likely help us gain better insight into polyamines and their derivatives to further develop functional foods and personalized nutraceuticals.


Assuntos
Poliaminas , Espectrometria de Massas em Tandem , Animais , Espermidina , Plantas , Espermina
3.
Int J Biol Macromol ; 261(Pt 2): 129918, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309388

RESUMO

This study examined four types of japonica rice from Yangtze River Delta, categorized based on amylose content (AC) and protein content (PC): high AC with high PC, high AC with low PC, low AC with high PC, and low AC with low PC. It systematically explored the effect of starch, protein and their interactions on eating quality of japonica rice. Rheological analysis revealed that increased amylose, long chains amylopectin or protein levels during cooking strengthen starch-protein interactions (hydrogen bonding), forming a firm gel network. Scanning electron microscopy showed that increased amylose, long chains amylopectin or protein levels made protein and starch more stable in combination during cooking, limiting starch structure cleavage. Therefore, the eating quality of high AC in similar PC japonica rice and high PC in similar AC japonica rice were poor. Further, correlation and random-forest analysis (RFA) identified amylose as the most influential factor in starch-protein interactions affecting rice eating quality, followed by amylopectin and protein. RFA also revealed that in high AC japonica rice, the interactions of Fb3 and albumin with amylose were more conducive to forming good eating quality. In low AC japonica rice, the interactions of Fb2 and prolamin with amylose were more beneficial.


Assuntos
Oryza , Amido , Amido/química , Amilopectina/química , Amilose/química , Oryza/química , Rios
4.
Chem Biodivers ; : e202400085, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329156

RESUMO

A lesser-known bee product called drone brood homogenate (DBH, apilarnil) has recently attracted scientific interest for its chemical and biological properties. It contains pharmacologically active compounds that may have neuroprotective, antioxidant, fertility-enhancing, and antiviral effects. Unlike other bee products, the chemical composition of bee drone larva is poorly studied. This study analyzed the chemical compostion of apilarnil using several methods. These included liquid chromatography-mass spectrometry (LC-MS/MS) and a combination of gas chromatography/mass spectrometry with solid phase micro-extraction (SPME/GC-MS). Additionally, antioxidant activity of the apilarnil was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. A chemical assessment of apilarnil showed that it has 6.3±0.00, 74.67±0.10 %, 3.65±0.32 %, 8.80±1.01 %, 13.16±0.94 %, and 8.79±0.49 % of pH, moisture, total lipids, proteins, flavonoids, and carbohydrates, respectively. LC-MS/MS analysis and molecular networking (GNPS) of apilarnil exhibited 44 compounds, including fatty acids, flavonoids, glycerophospholipids, alcohols, sugars, amino acids, and steroids. GC-MS detected 30 volatile compounds in apilarnil, mainly esters (24 %), ketones (23.84 %), ethers (15.05 %), alcohols (11.41 %), fatty acids (10.06), aldehydes (6.73 %), amines (5.46), and alkene (5.53 %). The antioxidant activity of apilarnil was measured using DPPH with an IC50 of 179.93±2.46 µg/ml.

5.
Food Res Int ; 178: 113934, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309905

RESUMO

Bee pollen is hailed as a treasure trove of human nutrition and has progressively emerged as the source of functional food and medicine. This review conducts a compilation of nutrients and phytochemicals in bee pollen, with particular emphasis on some ubiquitous and unique phenolamides and flavonoid glycosides. Additionally, it provides a concise overview of the diverse health benefits and therapeutic properties of bee pollen, particularly anti-prostatitis and anti-tyrosinase effects. Furthermore, based on the distinctive structural characteristics of pollen walls, a substantial debate has persisted in the past concerning the necessity of wall-disruption. This review provides a comprehensive survey on the necessity of wall-disruption, the impact of wall-disruption on the release and digestion of nutrients, and wall-disruption techniques in industrial production. Wall-disruption appears effective in releasing and digesting nutrients and exploiting bee pollen's bioactivities. Finally, the review underscores the need for future studies to elucidate the mechanisms of beneficial effects. This paper will likely help us gain better insight into bee pollen to develop further functional foods, personalized nutraceuticals, cosmetics products, and medicine.


Assuntos
Nutrientes , Pólen , Abelhas , Humanos , Animais , Pólen/química , Flavonoides/análise , Glicosídeos/análise , Compostos Fitoquímicos/análise
6.
Sci Rep ; 14(1): 4681, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409441

RESUMO

The preparation process and composition design of heavy-section ductile iron are the key factors affecting its fracture toughness. These factors are challenging to address due to the long casting cycle, high cost and complex influencing factors of this type of iron. In this paper, 18 cubic physical simulation test blocks with 400 mm wall thickness were prepared by adjusting the C, Si and Mn contents in heavy-section ductile iron using a homemade physical simulation casting system. Four locations with different cooling rates were selected for each specimen, and 72 specimens with different compositions and cooling times of the heavy-section ductile iron were prepared. Six machine learning-based heavy-section ductile iron fracture toughness predictive models were constructed based on measured data with the C content, Si content, Mn content and cooling rate as input data and the fracture toughness as the output data. The experimental results showed that the constructed bagging model has high accuracy in predicting the fracture toughness of heavy-section ductile iron, with a coefficient of coefficient (R2) of 0.9990 and a root mean square error (RMSE) of 0.2373.

7.
Plant Physiol Biochem ; 207: 108395, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38290342

RESUMO

Flowering is an important developmental transition that greatly affects the yield of many vegetable crops. In cucumber (Cucumis sativus), flowering is regulated by various factors including squamosa promoter-binding-like (SPL) family proteins. However, the role of CsSPL genes in cucumber flowering remains largely unknown. In this study, we cloned the squamosa promoter-binding-like protein 13A (CsSPL13A) gene, which encodes a highly conserved SBP-domain protein that acts as a transcription factor and localizes to the nucleus. Quantitative real-time PCR (qRT-PCR) analysis showed that CsSPL13A was mainly expressed in flowers, and its expression level increased significantly nearing the flowering stage. Additionally, compared with the wild type(WT), CsSPL13A-overexpressing transgenic cucumber plants (CsSPL13A-OE) showed considerable differences in flowering phenotypes, such as early flowering, increased number of male flowers, and longer flower stalks. CsSPL13A upregulated the expression of the flowering integrator gene Flowering Locus T (CsFT) and the sugar-mediated flowering gene ß-amylase (CsBAM) in cucumber. Yeast one-hybrid and firefly enzyme reporter assays confirmed that the CsSPL13A protein could directly bind to the promoters of CsFT and CsBAM, suggesting that CsSPL13A works together with CsFT and CsBAM to mediate flowering in cucumber. Overall, our results provide novel insights into the regulatory network of flowering in cucumber as well as new ideas for the genetic improvement of cucumber varieties.


Assuntos
Cucumis sativus , Cucumis sativus/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Flores/metabolismo , Fenótipo , Regiões Promotoras Genéticas/genética , Regulação da Expressão Gênica de Plantas
8.
J Agric Food Chem ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37921636

RESUMO

We aimed to identify the characteristic phytochemicals of safflower, Chinese sumac, and bauhinia honeys to assess their authenticity. We discovered syringaldehyde, riboflavin, lumiflavin, lumichrome, rhusin [(1E,4E)-1,5-diphenylpenta-1,4-dien-3-one-O-cinnamoyl oxime], bitterin {4-hydroxy-4-[3-(1-hydroxyethyl) oxiran-2-yl]-3,5,5-trimethylcyclohex-2-en-1-one}, and unedone as characteristic phytochemicals of these three types of honeys. The average contents of syringaldehyde, riboflavin, lumiflavin, or lumichrome in safflower honey were 41.20, 5.24, 24.72, and 36.72 mg/kg; lumiflavin, lumichrome, and rhusin in Chinese sumac honey were 39.66, 40.55, and 2.65 mg/kg; bitterin, unedone, and lumichrome in bauhinia honey were 8.42, 26.33, and 8.68 mg/kg, respectively. To our knowledge, the simultaneous presence of riboflavin, lumichrome, and lumiflavin in honey is a novel finding responsible for the bright-yellow color of honey. Also, it is the first time that lumiflavin, rhusin, and bitterin have been reported in honey. We effectively distinguish pure honeys from adulterations, based on characteristic components and high-performance liquid chromatography fingerprints; thus, we seem to provide intrinsic markers and reliable assessment criteria to assess honey authenticity.

9.
Front Plant Sci ; 14: 1281309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881617

RESUMO

Nitrogen (N) rate reduction and simplified fertilization can mitigate environmental impacts and reduce the involvement of manual labor in rice (Oryza sativa L.) production. Controlled-release urea (CRU) has been recommended as an effective alternative technique to conventional urea fertilization, and it can improve rice yield and N use efficiency (NUE) and reduce labor costs. However, the information on the effects of one-time fertilization with CRU on maintaining yield and improving NUE under reduced chemical N conditions is limited. In this study, controlled-release bulk blending fertilizer (CRF), consisting of CRU with release periods of 40 and 100 days, mixed with compound fertilizer, was applied as basal fertilizer. Increased ~20% plant density (ID) and rapeseed cake fertilizer (RC, increase 20% organic N) were combined with CRF, respectively. The N treatments with 20% chemical N reduction were as follows: reduced N fertilizer (RNF), CRF, CRF+ID, and CRF+RC. In addition, a conventional split fertilizer application with 300 kg ha-1 N was applied as the control (CK). Rice yield and its components, dry matter accumulation, N uptake, and NUE were investigated to evaluate whether one-time N fertilization realized stable yield and high NUE under reduced 20% chemical N conditions. Compared with CK, the CRF+RC treatment exhibited a comparable grain yield, while the other reduced N treatments (RNF, CRF, and CRF+ID) had a lower grain yield. Moreover, CRF+ID exhibited a higher rice grain yield than RNF or CRF under the same N level. Irrespective of exogenous organic N, CRF+RC exhibited significantly higher NUE than CK. The CRF+ID treatment showed a significantly higher N partial factor productivity (PFN) than CK but comparable N agronomic efficiency (NAE) and N recovery efficiency (NRE). Therefore, a one-time fertilizer application of CRF+RC maintained grain yield and improved the NUE while reducing the N rate and fertilization times, demonstrating its potential application in rice production.

10.
Foods ; 12(19)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37835330

RESUMO

Zinc deficiency in rice can lead to reduced nutritional value and taste. This study investigates the potential of zinc oxide nanoparticles (ZnO NPs) as a foliar fertilizer during the jointing stage to improve rice yield, quality, and grain zinc enrichment. Over a two-year field experiment (2019-2020), six doses of ZnO NPs (ranging from 0 to 12 kg hm-2) were applied during the jointing stage (46 days after transplanting). The results revealed that foliar spraying of ZnO NPs increased the number of spikelets per spike and the thousand-grain weight by 7.4% to 9.2% and 4.2% to 7.1%, respectively, resulting in a substantial increase in rice yield. Furthermore, it led to a reduction in chalky white and chalky whiteness by 6.23% to 23.6% and 2.2% to 27.9%. ZnO NPs effectively boosted zinc content in rice grains while decreasing the phytic acid to zinc ratio, indicating improved zinc enrichment. Remarkably, protein and amylose content remained unaffected. These findings underscore the potential of ZnO NPs as a foliar fertilizer to enhance rice production, quality, and zinc enrichment. Further research can explore optimal application strategies and long-term effects for sustainable rice production.

11.
Sci Total Environ ; 905: 167629, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37838042

RESUMO

Integrated rice-crayfish farming is an ecological rice farming mode. However, limited research has examined the comprehensive impacts of greenhouse gas (GHG) emissions, nitrogen (N) uptake, and N utilization in rice under this farming modality. Herein, a dual-factor experiment was performed from 2021 to 2022 to assess the comprehensive impacts of N application and rice farming mode on greenhouse gas (GHG) emissions, N uptake, N utilization, and rice yield in paddy fields. Under N application, the rice-crayfish co-culture exhibits a 2.3 % decrease in global warming potential (GWP) and a 17.3 % increase in greenhouse gas intensity relative to the rice monoculture. Moreover, the N uptake of rice within the rice-crayfish co-culture is 5.2 %-10.4 % higher than that in the rice monoculture. However, owing to low rice yield under the rice-crayfish co-culture, its N partial factor productivity decreases by 5.6 %-22.6 %, while N agronomic efficiency is reduced by 18.3 %-46.9 % compared with the rice monoculture. In addition, N application significantly inhibits CH4 emissions from paddy fields in the rice-crayfish co-culture mode. Compared with no N application, the CH4 emissions and GWP of N-applied treatment are decreased by 12.1 %-31.0 % and 6.0 %-15.8 %, respectively. Hence, N regulation might reduce GHG emissions in rice-aquatic animal co-culturing agriculture. Collectively, the results of this study suggest that switching from a rice monoculture to rice-crayfish co-culture can mitigate GHG emissions and promote rice N uptake; however, continuously improving the productivity of co-culturing agriculture is key to achieving high N utilization efficiency and low environmental impact.


Assuntos
Gases de Efeito Estufa , Oryza , Animais , Gases de Efeito Estufa/análise , Astacoidea , Nitrogênio , Solo , Metano/análise , Óxido Nitroso/análise , Agricultura/métodos , Fertilizantes/análise
12.
Plants (Basel) ; 12(10)2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37653963

RESUMO

There is limited information available to assess the impact of one-time fertilization on the yield, quality, and economic benefits of direct-seeded rice. This study reports the effects of three one-time fertilizer treatments (BBU1, BBU2, and BBU3) on the yield, quality, and economic benefits of direct-seeded rice, where controlled-release nitrogen (N) fertilizer (CRNF) provided 50%, 60%, and 70% of the total N (270 kg N ha-1), and the control treatment (CK) was a split application of conventional urea (CU). The results showed that the yield of direct-seeded rice decreased significantly (p < 0.05) with the increased application ratio of CRNF under one-time fertilization, which was mainly related to N accumulation between the heading time and maturity stages. Compared to CK, the one-time fertilization treatments (BBU1, BBU2, and BBU3) maintained high milling quality, with significantly reduced chalkiness (p < 0.05), which could be related to the slow rate of N release from the CRNF. In addition, the one-time fertilization treatments reduced the protein content and increased the amylose content of the milled rice, which significantly improved the eating quality (p < 0.05). Furthermore, there was no significant difference in yield and economic benefit between BBUI and CK (p > 0.05). Overall, CRNF replacing conventional urea with 50% total N could be helpful to reduce fertilization frequency, achieve high yield and high economic efficiency, and improve rice quality of direct-seeded rice under one-time fertilization.

13.
Front Plant Sci ; 14: 1196201, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662145

RESUMO

Zinc oxide nanoparticles (ZnO NPs) have been widely used in agriculture as a new type of Zn fertilizer, and many studies were conducted to evaluate the effect of ZnO NPs on plant growth. However, there are relatively few studies on the effects of application methods and appropriate dosages of ZnO NPs on rice yield, quality, grain Zn content, and distribution. Therefore, in the 2019 and 2020, field trials were conducted with six ZnO NPs basal application dosages of no ZnO NPs, 3.75 kg hm-2, 7.5 kg hm-2, 15 kg hm-2, 30 kg hm-2, and 60 kg hm-2, and the effects of ZnO NPs application on rice yield, quality, grain Zn content, and distribution were investigated. The results demonstrated that applying ZnO NPs in Zn-deficient soils (available Zn < 1.0 mg kg-1) increased rice grain yield by 3.24%-4.86% and 3.51%-5.12% in 2019 and 2020, respectively. In addition, ZnO NPs improved the quality of rice by increasing the head milling rate, reducing chalky grain percentage, and increasing the taste value and breakdown of rice. In terms of Zn accumulation in rice, ZnO NPs application significantly increased the Zn content in both milled rice and brown rice, compared with no Zn treatment, in 2019 and 2020, Zn content in milled rice significantly increased by 20.46%-41.09% and 18.11%-38.84%, respectively, and in brown rice significantly increased by 25.78%-48.30% and 20.86%-42.00%, respectively. However, the Zn fertilizer utilization gradually decreased with increasing ZnO NPs application dosage. From the perspective of yield, rice quality, Zn fertilizer utilization, and Zn accumulation, basal application of 7.5 kg-30 kg hm-2 ZnO NPs is beneficial for rice yield and quality improvement and rice Zn accumulation. This study effectively demonstrated that ZnO NPs could be a potential high-performed fertilizer for enhancing rice yield, quality, and zinc content of edible grain fraction synergistically.

14.
Rice (N Y) ; 16(1): 36, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37599294

RESUMO

The search for an effective zinc fertilizer and its application method to effectively increase zinc content and enhance aroma in rice grains is a crucial objective. In this study, a 2-year field plot experiment was conducted to investigate the influence of ZnO NPs foliar spraying on rice quality, grain zinc and aroma content, along with exploring the physiological mechanisms underlying these effects. Our results demonstrated that the rice breakdown value and taste value of foliar spraying zinc oxide nanoparticles were improved by 31.0-41.7% and 8.2-13.0% compared with CK (control treatment involved spraying water), improving the tasting and steaming quality of rice. While Fe and Cu content in grains decreased for the application of zinc oxide nanoparticles, zinc oxide nanoparticles foliar spraying significantly increased the zinc content and accumulation of grains by 33.6-65.1% and 37.8-74.7%, respectively. Further analysis showed that the sprayed zinc oxide nanoparticles achieved effective enrichment of zinc in edible parts and increased the final bioavailability of Zn. In addition, foliar spraying of zinc oxide nanoparticles significantly increased activities of nitrate reductase and glutamine synthetase in leaves, which elevated nitrogen content in leaves and grains, and ultimately enhanced 2-acetyl-1-pyrroline (2-AP) content in grains at maturity by 6.1-21.4% compared to CK. Our findings indicated that zinc oxide nanoparticles can be practically applied as a foliar fertilizer at the gestation for quality improvement, zinc enrichment and aroma enhancement of rice grains.

15.
Food Chem X ; 18: 100720, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37397194

RESUMO

The correlation between flavonoids, phenolic metabolites and the total antioxidant capacity is well established. However, specific biomarkers of metabolites with antioxidant properties in purple rice grains remain unidentified. This study integrated nontargeted metabolomics, quantitative detection of flavonoids and phenolic compounds, and physiological and biochemical data to identify metabolite biomarkers of the antioxidant properties of purple rice grains after filling. The findings demonstrated a significant enhancement in the biosynthesis of flavonoids during the middle and late filling stages in purple rice grains. Additionally, the pathways involved in anthocyanin and flavonoid biosynthesis were significantly enriched. Catalase (CAT), phenylalanine ammonia-lyase (PAL), total phenols (TP), flavonoids (FD), and oligomeric proanthocyanidin (OPC) were significantly correlated with philorizin, myricetin 3-galactoside, and trilobatin. Phlorizin, myricetin 3-galactoside, and trilobatin were metabolite biomarkers of antioxidant properties in purple rice grains. This study provides new ideas for the cultivation of high-quality coloured rice varieties with high antioxidant activity.

16.
J Sci Food Agric ; 103(15): 7896-7904, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37486857

RESUMO

BACKGROUND: Rapeseed bee pollen has been recognized as a critical treatment for chronic non-bacterial prostatitis (CNP) and it also can modulate gut microbiota and improve gut health. This study aimed to explore the anti-prostatitis effects of rapeseed bee pollen with or without wall-disruption, and to investigate the connection between this treatment and gut microbiota. RESULTS: The results reveal that rapeseed bee pollen can effectively alleviate chronic non-bacteria prostatitis by selectively regulating gut microbiota, with higher doses and wall-disrupted pollen showing greater efficacy. Treatment with a high dose of wall-disrupted rapeseed bee pollen (WDH, 1.26 g kg-1 body weight) reduced prostate wet weight and prostate index by approximately 32% and 36%, respectively, nearly the levels observed in the control group. Wall-disrupted rapeseed bee pollen treatment also reduced significantly (p < 0.05) the expression of proinflammatory cytokines (IL-6, IL-8, IL-1ß, and TNF-α), as confirmed by immunofluorescence with laser scanning confocal microscope. Our results show that rapeseed bee pollen can inhibit pathogenic bacteria and enhance probiotics, particularly in the Firmicutes-to-Bacteroidetes (F/B) ratio and the abundance of Prevotella (genus). CONCLUSION: This is the first study to investigate the alleviation of CNP with rapeseed bee pollen through gut microbiota. These results seem to provide better understanding for the development of rapeseed bee pollen as a complementary medicine. © 2023 Society of Chemical Industry.


Assuntos
Brassica napus , Brassica rapa , Microbioma Gastrointestinal , Prostatite , Humanos , Masculino , Abelhas , Animais , Prostatite/tratamento farmacológico , Prostatite/metabolismo , Pólen/metabolismo , Bactérias/genética
17.
Foods ; 12(12)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37372514

RESUMO

(1) Background: Propolis has attracted attention in recent years due to its important pharmacological effects. The present study aimed to investigate the botanical origins of 39 propolis samples and evaluate their antioxidant activities; (2) Methods: A HPLC-PDA system was used to analyze the phenolic compositions of propolis and poplar bud resin samples. The antioxidant activities of propolis samples were evaluated by oxygen radical absorption capacity (ORAC) and superoxide anion free radical scavenging capacity assay; (3) Results: Our study shows that 17 propolis samples were characterized by five predominant flavonoids, including 5-methoxy pinobanksin, pinobanksin, pinocembrin, pinobanksin-3-acetate, and chrysin, while 22 propolis samples were characterized by four flavonoids (pinobanksin, pinocembrin, pinobanksin-3-acetate, and chrysin). The average contents of characteristic flavonoids reached up to over 70% and 65% of total phenolics, respectively. Furthermore, the botanical origins of the two types of propolis samples were identified as Populus × euramericana cv. 'Neva' and Populus Simonii × P. nigra, respectively; (4) Conclusions: Most notably, our results reveal that these propolis samples presented excellent antioxidant activities due to their high contents of flavonoid. These flavonoid-rich propolis samples can thus be used to develop low-allergen and high-antioxidant nutraceuticals.

18.
J Sci Food Agric ; 103(12): 5747-5753, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37079446

RESUMO

BACKGROUND: Biochar can play a key role in improving paddy soil and productivity. However, there is limited information on the effects of biochar on rice quality and starch gelatinization. In this study, four rice straw biochar dosage treatments (0, 20, 40 and 60 g kg-1 ; CK, C20, C40 and C60, respectively) were set up to investigate rice yield components, rice processing, appearance and cooking quality, and starch gelatinization. RESULTS: Addition of biochar increased the effective panicle, grain number per panicle and seed setting rate. However, it decreased the 1000-grain weight, resulting in an increase in yield. In 2019, all the biochar treatments improved the head rice rate (9.13-11.42%), whereas in 2020 only the C20 treatment improved. Low biochar dosage had little effect on grain appearance. High biochar dosage significantly decreased the chalky rice rate by 21.47% and chalkiness by 19.44% in 2019. However, it significantly increased the chalky rice rate and chalkiness by 118.95% and 85.45% in 2020, respectively. Biochar significantly lowered the amylose content except for the C20 and C40 treatments in 2020, and the gel consistency. The C40 and C60 treatments significantly increased the peak and breakdown viscosities and decreased the setback viscosity compared with CK. Correlation analysis showed that starch gelatinization characteristics were significantly correlated with the head rice rate, chalky rate and amylose content. CONCLUSION: A lower biochar dosage can improve the yield and milled rice rate and maintain a higher quality of appearance, whereas a higher biochar dosage can significantly improve starch gelatinization. © 2023 Society of Chemical Industry.


Assuntos
Oryza , Amido , Amido/química , Amilose/análise , Oryza/química , Viscosidade , Grão Comestível/química
19.
Sci Total Environ ; 879: 163102, 2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-36966835

RESUMO

Wheat-rice cropping system in China, characterized by smallholder with conventional practice, is energy- and carbon-intensive. Cooperative with scientific practice is a promising practice to increase resource use while reducing environmental impact. However, comprehensive studies of the energy and carbon (C) budgeting of management practices on the actual field-scale production under different production types are lacking. The present research examined the energy and C budgeting of smallholder and cooperative using conventional practice (CP) or scientific practice (SP) at the field scale level in the Yangtze River Plain, China. The SPs and cooperatives exhibited 9.14 % and 6.85 % and 4.68 % and 2.49 % higher grain yields over the corresponding CPs and smallholders, respectively, while maintaining 48.44 % and 28.50 % and 38.81 % and 20.16 % higher net income. Compared to the CPs, the corresponding SPs reduced the total energy input by 10.35 % and 7.88 %, and the energy savings were primarily attributable to reductions in fertilizer, water, and seeds through the use of improved techniques. The total energy input in the cooperatives was 11.53 % and 9.09 % lower than that for the corresponding smallholders due to the mechanistic enhancements and improved operational efficiency. As a result of the increased yields and reduced energy inputs, the SPs and cooperatives ultimately increased energy use efficiency. The high productivity attributed to increased C output in the SPs, which increased C use efficiency and the C sustainability index (CSI) but decreased the C footprint (CF) over the corresponding CPs. The higher productivity and more efficient machinery of cooperatives increased the CSI and reduced the CF compared to the corresponding smallholders. Overall, the SPs coupled with cooperatives were the most energy efficient, C efficient, profitable and productive for wheat-rice cropping systems. In the future, improved fertilization management practices and integration of smallholder farms were effective means for developing sustainable agriculture and promoting environmental safety.

20.
Front Plant Sci ; 14: 1074148, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818874

RESUMO

In view of the significant differences among genotypes in the appearance of soft rice, it is necessary to conduct research on the differences in the appearance quality of soft rice and their mechanisms. It can provide a theoretical basis for the selection and breeding of superior appearance varieties at a later stage. In order to clarify the differences in appearance phenotypes between different soft rice genotypes and structural basis of endosperm structures behind the differences, four soft rice varieties were selected in this study, including two varieties with good-appearance and two varieties with cloudy appearance. The differences in appearance phenotypes and endosperm structure in mature grains of soft rice with different appearance phenotypes were scientifically analyzed. The development process of their endosperm differences at the filling stage was investigated. The results show that the difference in the rice appearance of soft rice varieties mainly lay in the chalk-free seed transparency and chalkiness. These differences were caused by two completely different types of endosperm structure. Fewer and smaller starch grain cavities were responsible for higher chalk-free transparency of soft rice grains, denser starch granules arrangement caused lower chalkiness of soft rice grains. Ten days after flowering, the starch granules in the back and heart of good-appearance soft rice were already significantly fuller and more closely packed than those of cloudy soft rice. At the same time, the number and area of starch granule holes were significantly smaller than those of cloudy soft rice. This difference gradually increased until maturity. Therefore, based on appearance evaluation, soft rice with good-appearance should have higher transparency and lower chalkiness. The endosperm starch granules should be full and tightly arranged. The number of starch grain cavities and the area should be smaller. These differences develop in the early stages of grouting and gradually increase.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...