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1.
Chem Biodivers ; 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34651409

RESUMO

Pomelo seeds (PS) are important by-product of pomelo fruits (Citrus grandis Osbeck). The value-added utilization of PS remains highly challenged. This study aimed to investigate the utilization potential of PS as natural antioxidant, antibacterial, herbicidal agents, and their functional components. The ethanolic extract (EE) of PS and its four fractions as PEE (petroleum ether extract), EtOAcE (ethyl acetate extract), BTE (n-butanol extract), and WE (water extract), were prepared and biologically evaluated. BTE exhibited the best antioxidant activity among all these extracts, in both ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and FRAP (ferric reducing antioxidant power) assays. EtOAcE was superior to other extracts in herbicidal assay against both Festuca elata Keng (IC50 of 0.48 mg mL-1) and Amaranthus retroflexus L. (IC50 of 0.94 mg mL-1). Meanwhile, both EtOAcE and BTE demonstrated inhibitory effects against Bacillus subtilis, Escherichia coli, and Xanthomonas citri subsp. citri, with MIC ranging 2.5-5.0 mg mL-1. Furthermore, the primary chemical components involving naringin, deacetylnomilin, limonin, nomilin, and obacunone, were quantified in all these extracts. PCA (principal component analysis) suggested that naringin might highly contribute to the antioxidant activity of PS, and the herbicidal activity should be ascribed to limonoids. This study successfully identified EtOAcE and BTE as naturally occurring antioxidant, antibacterial, and herbicidal agents, showing application potential in food and cosmetics industries, and organic farming agriculture.

2.
Molecules ; 26(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199966

RESUMO

Nanfeng mandarins (Citrus reticulata Blanco cv. Kinokuni), Xunwu mandarins (Citrus reticulata Blanco), Yangshuo kumquats (Citrus japonica Thunb) and physiologically dropped navel oranges (Citrus sinensis Osbeck cv. Newhall) were used as materials to extract peel essential oils (EOs) via hydrodistillation. The chemical composition, and antibacterial and antioxidant activities of the EOs were investigated. GC-MS analysis showed that monoterpene hydrocarbons were the major components and limonene was the predominate compound for all citrus EOs. The antibacterial testing of EOs against five different bacteria (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium) was carried out using the filter paper method and the broth microdilution method. Kumquat EO had the best inhibitory effect on B. subtilis, E. coli and S. typhimurium with MIC (minimum inhibitory concentration) values of 1.56, 1.56 and 6.25 µL/mL, respectively. All citrus EOs showed the antioxidant activity of scavenging DPPH and ABTS free radicals in a dose-dependent manner. Nanfeng mandarin EO presented the best antioxidant activity, with IC50 values of 15.20 mg/mL for the DPPH assay and 0.80 mg/mL for the ABTS assay. The results also showed that the antibacterial activities of EOs might not be related to their antioxidant activities.


Assuntos
Antibacterianos/química , Antioxidantes/química , Citrus/química , Óleos Voláteis/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Bacillus subtilis/efeitos dos fármacos , Citrus/classificação , Destilação , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos Vegetais/química , Óleos Vegetais/isolamento & purificação , Óleos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
3.
Insect Sci ; 28(3): 718-734, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32428381

RESUMO

The Asian citrus psyllid, Diaphorina citri is the principal vector of huanglongbing, which transmits Candidatus Liberibacter asiaticus. Trehalase is a key enzyme involved in trehalose hydrolysis and plays an important role in insect growth and development. The specific functions of this enzyme in D. citri have not been determined. In this study, three trehalase genes (DcTre1-1, DcTre1-2, and DcTre2) were identified based on the D. citri genome database. Bioinformatic analysis showed that DcTre1-1 and DcTre1-2 are related to soluble trehalase, whereas DcTre2 is associated with membrane-bound trehalase. Spatiotemporal expression analysis indicated that DcTre1-1 and DcTre1-2 had the highest expression levels in the head and wing, respectively, and DcTre2 had high expression levels in the fat body. Furthermore, DcTre1-1 and DcTre1-2 expression levels were induced by 20-hydroxyecdysone and juvenile hormone Ⅲ, but DcTre2 was unaffected. The expression levels of DcTre1-1, DcTre1-2, and DcTre2 were significantly upregulated, which resulted in high mortality after treatment with validamycin. Trehalase activities and glucose contents were downregulated, but the trehalose content increased after treatment with validamycin. In addition, the expression levels of chitin metabolism-related genes significantly decreased at 24 and 48 h after treatment with validamycin. Furthermore, silencing of DcTre1-1, DcTre1-2, and DcTre2 reduced the expression levels of chitin metabolism-related genes and led to a malformed phenotype of D. citri. These results indicate that D. citri trehalase plays an essential role in regulating chitin metabolism and provides a new target for control of D. citri.


Assuntos
Hemípteros , Trealase , Animais , Quitina/metabolismo , Regulação da Expressão Gênica , Genes de Insetos , Hemípteros/genética , Hemípteros/metabolismo , Inositol/análogos & derivados , Inositol/farmacologia , Controle de Pragas , Interferência de RNA , Trealase/efeitos dos fármacos , Trealase/genética , Trealase/metabolismo , Trealose/metabolismo
4.
Phytopathology ; : PHYTO09200436R, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-33356429

RESUMO

Huanglongbing (HLB) is a devastating citrus disease worldwide. A three-pronged approach to controlling HLB has been suggested, namely, removal of HLB-symptomatic trees, psyllid control, and replacement with HLB-free trees. However, such a strategy did not lead to successful HLB control in many citrus-producing regions, such as Florida. We hypothesize that this is because of the small-scale or incomprehensive implementation of the program; conversely, a comprehensive implementation of such a strategy at the regional level can successfully control HLB. To test our hypothesis, we investigated the effects of region-wide comprehensive implementation of this scheme to control HLB in Gannan region, China, with a total planted citrus acreage of over 110,000 ha from 2013 to 2019. With the region-wide implementation of comprehensive HLB management, the overall HLB incidence in Gannan decreased from 19.71% in 2014 to 3.86% in 2019. A partial implementation of such a program (without a comprehensive inoculum removal) at the regional level in Brazil resulted in HLB incidence increasing from 1.89% in 2010 to 19.02% in 2019. Using dynamic regression model analyses with data from both Brazil and China, we constructed a model to predict HLB incidence when all three components were applied at 100%. It was predicated that in a region-wide comprehensive implementation of such a program, HLB incidence would be controlled to a level of less than 1%. We conducted economic feasibility analyses and showed that average net profits were positive for groves that implemented the comprehensive strategy, but groves that did not implement it had negative net profits over a 10-year period. Overall, the key for the three-pronged program to successfully control HLB is the large scale (region-wide) and comprehensiveness in implementation. This study provides valuable information to control HLB and other economically important endemic diseases worldwide.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

5.
Insect Sci ; 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33118290

RESUMO

Validamycin has been widely used as a specific competitive inhibitor of trehalase. In our previous research, validamycin significantly inhibited trehalase activity and chitin synthesis in Diaphorina citri, resulting in abnormal phenotypes. However, the mechanism of validamycin's action on D. citri remains unclear. Here, using a comparative transcriptome analysis, 464 differentially expressed genes (DEGs) in D. citri were identified after validamycin treatment. A Gene Ontology enrichment analysis revealed that these DEGs were mainly involved in "small molecule process", "structural molecule activity" and "transition metal ion binding". DEGs involved in chitin metabolism, cuticle synthesis and insecticide detoxification were validated by reverse transcription quantitative polymerase chain reaction. The RNA interference of D. citri chitinase-like protein ENO3 and D. citri cuticle protein 7 genes significantly affected D. citri molting. Moreover, the recombinant chitinase-like protein ENO3 exhibited a chitin-binding property, and an antimicrobial activity against Bacillus subtilis. This study provides a first insight into the molecular changes in D. citri after exposure to validamycin and identifies two effective RNA interference targets for D. citri control.

6.
Molecules ; 25(18)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32916953

RESUMO

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is the only natural vector of bacteria responsible for Huanglongbing (HLB), a worldwide destructive disease of citrus. ACP reproduces and develops only on the young leaves of its rutaceous host plants. Olfactory stimuli emitted by young leaves may play an important role in ACP control and HLB detection. In this study, volatile organic compounds (VOCs) from healthy and HLB-infected young leaves of navel orange and pomelo were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). A total of 36 compounds (including dimers or polymers) were identified and quantified from orange and 10 from pomelo leaves. Some compounds showed significant differences in signal intensity between healthy and HLB-infected leaves and may constitute possible indicators for HLB infection. Principal component analysis (PCA) clearly discriminated healthy and HLB-infected leaves in both orange and pomelo. HS-GC-IMS was an effective method to identify VOCs from leaves. This study may help develop new methods for detection of HLB or find new attractants or repellents of ACP for prevention of HLB.


Assuntos
Citrus/química , Doenças das Plantas/microbiologia , Folhas de Planta/química , Compostos Orgânicos Voláteis/análise , Animais , Bactérias , Cromatografia Gasosa , Citrus/classificação , Frutas , Hemípteros , Espectrometria de Mobilidade Iônica , Análise de Componente Principal , Software
7.
J Sci Food Agric ; 100(6): 2664-2674, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31997352

RESUMO

BACKGROUND: Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) is the major navel orange cultivar planted in China. Almost all Newhall navel orange peels produced in that country are currently discarded, which is not only harmful to the environment but also a waste of resources. It is therefore necessary to carry out research to explore the utilization potential of this resource. RESULTS: A 95% ethanol extract (EE) of Newhall orange peel was prepared and fractionated into three subextracts: petroleum ether extract (PEE), ethyl acetate extract (EtOAcE), and water extract (WE) by simple liquid / liquid extractions. These four extracts were then subjected to antioxidant, antibacterial, and tyrosinase inhibition assays. Interestingly, EtOAcE was significantly superior to all other three extracts, exhibiting the best biological effects. The total polyphenol content (TPC), total flavonoid content (TFC), and primary individual flavonoids of these four extracts were analyzed and compared. This was followed by principal component analysis (PCA) and the Pearson's correlation test. The result indicates that the primary bioactive compounds responsible for the biological effects of the EtOAcE are sinensetin, 4',5,6,7-tetramethoxyflavone, nobiletin, 3,3',4',5,6,7-hexamethoxyflavone, and narirutin. In view of its easy preparation and potent biological effects, EtOAcE might demonstrate excellent application potential in various industrial areas. CONCLUSIONS: This study successfully identified EtOAcE as a potent naturally occurring antioxidant, antibacterial, and tyrosinase inhibitory agent, which might add value to the utilization of Newhall navel orange peel in the food, cosmetic, and pharmaceutical industries. © 2020 Society of Chemical Industry.


Assuntos
Citrus sinensis/química , Frutas/química , Extratos Vegetais/química , Antibacterianos/farmacologia , Antioxidantes/análise , Bactérias/efeitos dos fármacos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Resíduos/análise
8.
Molecules ; 25(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948058

RESUMO

Grapefruit essential oil has been proven to have wide range of bioactivities. However, bioactivity of its molecular distillate has not been well studied. In this study, a light phase oil was obtained by molecular distillation from cold-pressed grapefruit essential oil and GC-MS was used to identify its chemical composition. The antimicrobial activity of the light phase oil was tested by filter paper diffusion method, and the anticancer activity was determined by the Cell Counting Kit-8 (CCK-8) assay. Twenty-four components were detected with a total relative content of 99.74%, including 97.48% of terpenes and 1.66% of oxygenated terpenes. The light phase oil had the best antimicrobial effect on Bacillus subtilis, followed by Escherichia coli, Staphylococcus aureus and Salmonellaty phimurium. DPPH and ABTS assays demonstrated that the light phase oil had good antioxidant activity. The CCK-8 assay of cell proliferation showed that the light phase oil had a good inhibitory effect on the proliferation of HepG2 liver cancer cells and HCT116 colon cancer cells.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Citrus paradisi/química , Destilação/métodos , Antibacterianos/efeitos adversos , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/efeitos adversos , Bacillus subtilis/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Células HCT116 , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/efeitos adversos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Óleos Vegetais/efeitos adversos , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos
9.
BMC Plant Biol ; 19(1): 254, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31195973

RESUMO

BACKGROUND: Asian citrus psyllid (ACP) is the primary vector responsible for the transmission of the phloem-limited bacteria Candidatus Liberibacter spp., associated with huanglongbing (HLB), which causes great loss to the citrus industry. Although the roles of leaf color and volatile compounds in the orientation of ACP have been proven, the quantification of color and allelochemicals in the host plant are kept unclear, especially in wild citrus germplasms. RESULTS: Chongyi wild mandarin significantly attracted more ACP than wild Hong Kong kumquat, 'Gannan zao' navel orange and orange jasmine did in the four-choice and olfactometer assays. The color parameters of the tender leaves from Chongyi wild mandarin and 'Gannan zao' were similar. The yellow color in both of them was less saturated than that of the other two plants species, but Chongyi wild mandarin had significant lower carotenoid content (P < 0.05). Notably metabolic profiling differences were observed among the healthy tender shoots from the four tested plants via UPLC-QQQ-MS and GC-MS analyses. Comparing with the other three plant species, 66 and 50 metabolites with significantly different contents in Chongyi wild mandarin were selected as UPLC-identified and GC-identified metabolites of interest (P < 0.05), respectively. Flavonoids accounted for a large group of secondary metabolites of interest, which may function as stimulants or repellents of ACP. Higher content of salicylic acid o-hexoside and lower content of (+)-jasmonic acid in Chongyi wild mandarin may lead to higher amount of methyl salicylate (an ACP attractant) and lower amount of trans-ocimene (an attractant to herbivores' natural enemies) as well as the suppression of JA-mediated wounding response. This kind of synergistic or antagonistic effect among the metabolites differentially accumulated in Chongyi wild mandarin made it a more attractive host plant to ACP. CONCLUSIONS: Less saturated yellow color, high amount of attractants, low amount of repellents and insensitivity of JA-mediated wounding response are the four possible reasons why Chongyi wild mandarin attracted more ACP. This work may shed light on the olfactory and visual response of ACP to wild citrus germplasm hosts, and suggest the feasibility of developing ACP attractants or repellents patterned on potential metabolites.


Assuntos
Hemípteros/fisiologia , Folhas de Planta/metabolismo , Rutaceae/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Citrus/metabolismo , Cor , Flavonoides/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos Voláteis/metabolismo
10.
Mar Drugs ; 17(2)2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30736380

RESUMO

In this study, as part of our continuous search for environmentally-friendly antifoulants from natural resources, subergorgic acid (SA) was identified from the gorgonian coral Subergorgia suberosa, demonstrating non-toxic, significant inhibitory effects (EC50 1.25 µg/mL, LC50 > 25 µg/mL) against the settlement of Balanus amphitrite. To further explore the bioactive functional groups of SA and synthesize more potent antifouling compounds based on the lead SA, the structure-activity relationships of SA were studied, followed by rational design and synthesis of two series of SA derivatives (one being benzyl esters of SA and another being SA derivatives containing methylene chains of various lengths). Our results indicated that (1) both the double bond and ketone carbonyl are essential elements responsible for the antifouling effect of SA, while the acid group is not absolutely necessary for maintaining the antifouling effect; (2) all benzyl esters of SA displayed good antifouling effects (EC50 ranged from 0.30 to 2.50 µg/mL) with the most potent compound being 5 (EC50 0.30 µg/mL, LC50 > 25 µg/mL), which was over four-fold more potent than SA; and (3) the introduction of a methylene chain into SA reduces the antifouling potency while the length of the methylene chain may differently influence the antifouling effect, depending on the functional group at the opposite site of the methylene chain. Not only has this study successfully revealed the bioactive functional groups of SA, contributing to the mechanism of SA against the settlement of B. amphitrite, but it has also resulted in the identification of a more potent compound 5, which might represent a non-toxic, high-efficiency antifoulant.


Assuntos
Antozoários/química , Incrustação Biológica/prevenção & controle , Sesquiterpenos/química , Animais , Compostos de Benzil/síntese química , Compostos de Benzil/farmacologia , Ésteres/síntese química , Ésteres/farmacologia , Estrutura Molecular , Sesquiterpenos/síntese química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Relação Estrutura-Atividade , Thoracica/efeitos dos fármacos
11.
Molecules ; 24(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704118

RESUMO

The essential oil of 'Gannanzao' orange peel was extracted by hydrodistillation, and the extraction conditions were optimized by Box⁻Behnken response surface methodology. The components of essential oil were analyzed by GC-MS. Thirty-nine different components were detected, accounting for 99.59% of the total oil. Limonene (88.07%) was the prominent component. The optimal extraction conditions were as follows: liquid material ratio of 8.4:1 (mL/g), sodium chloride concentration of 5.3%, and distillation time of 3.5 h. The Cell Counting Kit-8 assay showed that 'Gannanzao' orange peel essential oil had good dose-dependent inhibition effect on the proliferation of HepG2 hepatoma cells and HCT116 colorectal cancer cells. When the concentration of the essential oil was 0.6 µL/mL or higher, the viability rate of both cancer cells became lower than 13.0%. The transwell assay indicated the essential oil can inhibit migration of both cancer cells at the concentration of 0.3 µL/mL.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Citrus sinensis/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos Vegetais/química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Células HCT116 , Células Hep G2 , Humanos , Extração Líquido-Líquido , Espectroscopia de Ressonância Magnética , Óleos Vegetais/farmacologia
12.
Pest Manag Sci ; 75(5): 1339-1345, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30367747

RESUMO

BACKGROUND: Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, is an important pest of citrus worldwide because it transmits the bacteria causing huanglongbing (HLB). We investigated the effects and persistence of two soil application rates of thiamethoxam on ACP populations in two flushing seasons in the field. Thiamethoxam and clothianidin residues in the fruit were detected to evaluate food safety. RESULTS: Soil application of 50% thiamethoxam water-dispersible granules at concentrations of 4 and 10 g tree-1 significantly decreased ACP populations, and there was a positive correlation between control efficacy and the persistence of thiamethoxam and clothianidin in leaves, providing longer-term protection for up to 90 days in the fall compared with 60 days in the spring. Higher thiamethoxam and clothianidin amounts were observed in new leaves than in old leaves. Thiamethoxam and clothianidin residues at a high rate in fruit were 0.012 and 0.010 mg kg-1 at harvest, respectively, and neither insecticides was detectable at low rates. CONCLUSIONS: These results demonstrate that soil-applied thiamethoxam plays a role in defending ACP, and provides an extended period of control efficacy. This knowledge could provide a reference for the control of ACP by soil application of thiamethoxam to reduce HLB spread. © 2018 Society of Chemical Industry.


Assuntos
Citrus/metabolismo , Hemípteros , Estações do Ano , Solo/química , Tiametoxam/metabolismo , Animais , Transporte Biológico , Citrus/microbiologia , Inocuidade dos Alimentos , Guanidinas/metabolismo , Hemípteros/fisiologia , Resistência a Inseticidas , Limite de Detecção , Modelos Lineares , Neonicotinoides/metabolismo , Resíduos de Praguicidas/metabolismo , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Tiazóis/metabolismo
13.
Nat Commun ; 9(1): 4894, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30459421

RESUMO

Citrus is a globally important, perennial fruit crop whose rhizosphere microbiome is thought to play an important role in promoting citrus growth and health. Here, we report a comprehensive analysis of the structural and functional composition of the citrus rhizosphere microbiome. We use both amplicon and deep shotgun metagenomic sequencing of bulk soil and rhizosphere samples collected across distinct biogeographical regions from six continents. Predominant taxa include Proteobacteria, Actinobacteria, Acidobacteria and Bacteroidetes. The core citrus rhizosphere microbiome comprises Pseudomonas, Agrobacterium, Cupriavidus, Bradyrhizobium, Rhizobium, Mesorhizobium, Burkholderia, Cellvibrio, Sphingomonas, Variovorax and Paraburkholderia, some of which are potential plant beneficial microbes. We also identify over-represented microbial functional traits mediating plant-microbe and microbe-microbe interactions, nutrition acquisition and plant growth promotion in citrus rhizosphere. The results provide valuable information to guide microbial isolation and culturing and, potentially, to harness the power of the microbiome to improve plant production and health.


Assuntos
Citrus/microbiologia , Microbiota/genética , Raízes de Plantas/microbiologia , Rizosfera , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , DNA Espaçador Ribossômico/genética , Fungos/classificação , Fungos/genética , Metagenoma/genética , Metagenômica/classificação , Metagenômica/métodos , Filogenia , RNA Ribossômico 16S/genética
14.
Molecules ; 23(10)2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30347650

RESUMO

Delayed bitterness causes severe economic loss in citrus juice industry worldwide, which is mostly due to the formation of limonoid compounds, especially limonin, in juice. In this study, effects of postharvest time of fruits, heat treatment, pH and filtration of juice on limonin content in Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) juice were investigated. Our research indicated for the first time that: (1) limonin content in juice would gradually increase to a maximal level and then remained almost constant thereafter as storage time going on, whereas the maximum constant value (MCV) of limonin content in juice significantly (p < 0.05) decreased with the increment of postharvest time of fruits being juiced; (2) heat treatment and acidification of juice only speeded up the formation of limonin to the maximal level while without changing the MCV of limonin content; (3) the juice after filtration exhibited much lower MCV of limonin content compared with the unfiltered one. These experimental observations might not only provide useful information for the development of new debitterness method for navel orange juice, but also strongly support the acid-promoted delayed bitterness mechanism, suggesting the formation of delayed bitterness might primary due to the acid-promoted rather than the enzyme-catalyzed lactonization of limonoate A-ring lactone (LARL) to produce limonin in juice of navel orange.


Assuntos
Citrus sinensis/química , Sucos de Frutas e Vegetais/análise , Limoninas/química , Paladar , Temperatura Alta , Limoninas/isolamento & purificação
15.
Food Sci Nutr ; 6(6): 1431-1437, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30258585

RESUMO

The present investigation reported the chemical composition of cold pressed Gannan navel orange peel essential oil (EO) and its molecular distillation fraction (light phase EO), and examined their antimicrobial activity against spoiling and pathogenic microorganisms. Gas chromatography-mass spectrometry analysis identified 27 and 20 different chemical constituents in cold pressed EO and light phase EO, respectively. Limonene was the major constituent, accounting for 85.32% of cold pressed EO and 60.44% of light phase EO. Both EOs and some of their constituents showed good antimicrobial activity. Compared to cold pressed EO, light phase EO exhibited the better antimicrobial activity under weak acidic and neutral conditions. The light phase EO presented a higher antimicrobial activity after thermo-treatment at 60-100°C for 20 min than cold pressed EO. These results demonstrated that light phase EO had a potential to be used as a novel antimicrobial agent for food preservation and food processing.

16.
Mar Drugs ; 16(7)2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-29987219

RESUMO

Four new structurally related metabolites, one γ-lactone named gliomasolide F (1), one δ-lactone named gliomasolide G (2), and two medium-chain fatty acids named gliomacids A⁻B (3⁻4), each containing nine carbons in total, were identified from the sponge-associated fungus Gliomastix sp. ZSDS1-F7-2. The planar chemical structures of these novel C9 metabolites were elucidated by nuclear magnetic resonance (NMR) spectroscopic methods, in connection with the analysis of high-resolution mass spectrometry (HRMS) and infrared (IR) data. The absolute configuration of 1, was determined by comparisons of experimental circular dichroism (CD) and optical rotation (OR) value with corresponding ones computed by quantum chemistry. The relative configuration of 2 was determined by the Nuclear Overhauser effect spectroscopy (NOESY) spectrum, while its absolute configuration was tentatively determined in view of the biogenetic and biosynthetic relationships between 1 and 2. Compounds 3⁻4, originally as an inseparable mixture, were successfully isolated after chemical modifications. The stereo-chemistries of compounds 3⁻4 were assumed by comparison of 13C NMR with those of the similar moiety reported in literature, in addition to the biogenetic and biosynthetic relationships with 1. The plausible biosynthetic relationships among these four C9 metabolites were supposed. Biologically, compounds 1⁻4 showed no cytotoxic effect against HeLa cell line at concentrations up to 25 μg/mL, while 1 exhibited moderate antifouling activity against the settlement of Balanus amphitrite larvae with IC50 being 12.8 μg/mL and LC50 > 25 μg/mL. The co-occurrence of macrolides gliomasolides A—E and four C9 metabolites in the same fermentation culture made us assume that these C9 metabolites might be biosynthetic building blocks toward the construction of more complex macrolides such as gliomasolides A—E or other unidentified polyketides.


Assuntos
Ácidos Graxos/química , Hypocreales/metabolismo , Lactonas/química , Poríferos/microbiologia , Animais , Incrustação Biológica/prevenção & controle , Dicroísmo Circular , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/metabolismo , Ácidos Graxos/farmacologia , Células HeLa , Humanos , Concentração Inibidora 50 , Lactonas/isolamento & purificação , Lactonas/metabolismo , Lactonas/farmacologia , Larva/efeitos dos fármacos , Macrolídeos/metabolismo , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rotação Ocular , Policetídeos/metabolismo , Thoracica/efeitos dos fármacos
17.
J Asian Nat Prod Res ; 20(3): 255-262, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28537094

RESUMO

A pair of unusual melibiose esters (1α/1ß) and a pair of unusual raffinose esters (2α/2ß), were isolated from Scrophularia ningpoensis. Structures of them were established by detailed spectroscopic analyses to be 6-O-(E)-cinnamoyl-α-d-galactopyranosyl-(1→6)-α(ß)-d-glucopyranose (1α/1ß) and 6-O-(E)/(Z)-cinnamoyl-α-d-galactopyranosyl-(1→6)-α-d-glucopyranosyl-(1→2)-ß-d-fructofuranose (2α/2ß), respectively. All these compounds were evaluated for antifouling activity against the settlement of Balanus amphitrite larvae, along with the cytotoxic effect against the proliferation of HeLa cell lines.


Assuntos
Melibiose/isolamento & purificação , Rafinose/isolamento & purificação , Scrophularia/química , Animais , Incrustação Biológica/prevenção & controle , Ésteres , Células HeLa , Humanos , Larva/efeitos dos fármacos , Melibiose/química , Melibiose/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Rafinose/química , Rafinose/farmacologia , República de Belarus
18.
Molecules ; 22(8)2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28829378

RESUMO

China is one of the leading producers of citrus in the world. Gannan in Jiangxi Province is the top navel orange producing area in China. In the present study, an essential oil was prepared by cold pressing of Gannan navel orange peel followed by molecular distillation. Its chemical composition was analyzed by GC-MS. Twenty four constituents were identified, representing 97.9% of the total oil. The predominant constituent was limonene (74.6%). The anticancer activities of this orange essential oil, as well as some of its major constituents, were investigated by MTT assay. This essential oil showed a positive effect on the inhibition of the proliferation of a human lung cancer cell line A549 and prostate cancer cell line 22RV-1. Some of the oil constituents displayed high anticancer potential and deserve further study.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Óleos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Sobrevivência Celular , Citrus sinensis/química , Cicloexenos/química , Cicloexenos/farmacologia , Frutas/química , Humanos , Limoneno , Óleos Voláteis/química , Extratos Vegetais/química , Óleos Vegetais/química , Terpenos/química , Terpenos/farmacologia
19.
J Econ Entomol ; 110(4): 1556-1562, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28444322

RESUMO

Sweet orange oil fractions were prepared by molecular distillation of cold-pressed orange oil from sample A (Citrus sinensis (L.) 'Hamlin' from America) and sample B (Citrus sinensis Osbeck 'Newhall' from China) respectively, and their fumigant activities against medium workers of red imported fire ants (Solenopsis invicta Buren) were investigated. The volatile composition of the orange oil fractions was identified and quantified using GC-MS. Fractions from sample A (A1, A2, and A3) contained 23, 37, and 48 chemical constituents, and fractions from sample B (B1, B2, and B3) contained 18, 29, and 26 chemical constituents, respectively. Monoterpenes were the most abundant components, accounting for 73.56% to 94.86% of total orange oil fractions, among which D-limonene (65.28-80.18%), ß-pinene (1.71-5.58%), 3-carene (0.41-4.01%), ß-phellandrene (0.58-2.10%), and linalool (0.31-2.20%) were major constituents. Fumigant bioassay indicated that all orange oil fractions exerted good fumigant toxicity against workers of fire ants at 3, 5, 10, and 20 mg/centrifuge tubes, and B1 had the strongest insecticidal potential, followed by A1, B2, A2, B3, and A3. The fractions composed of more high volatile molecules (A1 and B1) showed greater fumigant effects than others. Compounds linalool and D-limonene, which were the constituents of the orange oil, exhibited excellent fumigant toxicity against red imported fire ant workers. Linalool killed red imported fire ant workers completely at 5, 10, and 20 mg/tube after 8 h of treatment, and D-limonene induced >86% mortality at 8 h of exposure.


Assuntos
Formigas/efeitos dos fármacos , Citrus sinensis/química , Fumigação/métodos , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Animais , Óleos Vegetais/farmacologia , Especificidade da Espécie
20.
Nat Prod Res ; 31(20): 2361-2368, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28326841

RESUMO

A new iridoid glycoside, namely 8-O-(threo-2, 3-dihydroxyl-3-phenyl-propionoyl)-harpagide (1), along with a new cinnamoyl glycoside named as cis-sibirioside A (2), were isolated from Scrophularia ningpoensis Hemsl. Their chemical structures were completely established by spectroscopic methods and comparison with related literatures. Compound 1 exhibited moderate antifouling effect against the settlement of Balanus amphitrite larvae with IC50 being 13.5 µg/mL and LC50 > 25 µg/mL.


Assuntos
Incrustação Biológica/prevenção & controle , Glicosídeos Iridoides/farmacologia , Scrophularia/química , Thoracica/efeitos dos fármacos , Animais , China , Glicosídeos Iridoides/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química
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