819 resultados para SINENSIS


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The difficulty in adult tissue genetic transformation in woody species is still an obstacle to be overcome, including in most sweet orange cultivars of the Brazilian citrus industry. This work reports that, after in vitro culture adjustments, transgenic adventitious buds of 'Hamlin', 'Pra', and 'Valencia' sweet oranges (Citrus sinensis L. Osbeck) were recovered using adult material as explant source, in genetic transformation experiments via Agrobacterium tumefaciens. The transgenic buds were identified by the GUS histochemical analysis and confirmed by PCR analysis, which indicated the presence of an amplified fragment of 817 bp corresponding to the uidA gene sequence. The efficiencies of genetic transformation for 'Hamlin', 'Pra', and 'Valencia' sweet orange cultivars were 2.5, 1.4, and 3.7%, respectively. Media supplemented with auxins and cytokinins during co-culture, and media with high concentrations of cytokinins (3 mg L-1) during transgenic selection led to the transformation and, consequently, the regeneration of adequate number of adventitious buds for the three cultivars. The use of sonication during the explant disinfection was not effective to reduce endophytic contamination and reduced transformation efficiency.

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The objective of this work was to select adequate early-maturing sweet orange cultivars for the fresh fruit market and for industrial processing using performance indexes. Performance indexes for citrus were established from data collected in an experiment carried out in the southwest region of the state of Sao Paulo, involving 12 early-maturing sweet orange cultivars. New results were obtained by identifying cultivars with superior characteristics. In a comparison with 'Hamlin' sweet orange, a standard early-maturing cultivar, 'Valencia 2' and 'Salustiana' were considered better materials for the fresh fruit market, whereas 'Westin' sweet orange was identified as a superior cultivar for orange juice processing.

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Callogenesis, somatic embryogenesis, and regeneration were obtained from tissues of unfertilized ovaries of sweet orange (Citrus sinensis Osbeck.) cv. Tobias. The influence of two modified basal media, woody plant medium (WPM) and N6 medium, to induce callus formation from pistils was determined. Overall, high frequencies of callogenesis were observed when either medium was used. However, initial culture of explants in WPM medium followed by transfer of callus to N6 medium resulted in higher frequency of callus induction (of 2.30 callus per explant that were larger than 0.5 cm in size), and of subsequent development of embryogenic callus (10%). A total of 125 somatic embryos were obtained. After 6 months of culture, 72% of somatic embryos germinated into plantlets. These plantlets were subsequently micrografted in vitro, and then acclimatized. Ploidy of these plants were determined using flow cytometry and TRAPS molecular markers were used to confirm their maternal origin.

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Four Citrus species (C. sinensis, cvs. Pera and Lima; C. latifolia Tanaka cv. Tahiti; C limettioides Tanaka cv. Sweet lime and C. reticulate, cv. Ponkan) grown in Brazil were characterised in relation to contents of minerals, ascorbic acid, total polyphenols and antioxidant capacity of pulps and peels. In general, the peels demonstrated significantly higher contents of all compounds than the pulps (p < 0.05), with the exception of the Pera orange pulp that presented the highest acid ascorbic content (68 mg/100 ml), while the Tahiti lime peel presented the lowest (8 mg/100 g). Citrus showed high levels of potassium, calcium and magnesium, and the peels were considered sources of these minerals. The Ponkan mandarin peel presented the highest antioxidant capacity. The antioxidant capacity of citrus was correlated both to vitamin C and phenolics. Aside from citrus pulps, the peels are also good sources of bioactive compounds and minerals, and can be explored for their health promoting values in food products. (C) 2012 Elsevier Ltd. All rights reserved.

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The aim of this study was to evaluate the gamma radiation effects on odor volatiles in oolong tea at doses of 0, 5, 10, 15 and 20 kGy. The volatile organic compounds were extracted by hydrodistillation and analyzed by GC/MS. The irradiation has a large influence on oolong tea odor profile, once it was identified 40% of new compounds after this process, the 5 kGy and 20 kGy were the doses that degraded more volatiles found naturally in this kind of tea and the dose of 10 kGy was the dose that formed more new compounds. Statistical difference was found between the 5 kGy and 15 kGy volatile profiles, however the sensorial analysis showed that the irradiation at dose up 20 kGy did not interfere on consumer perception. (C) 2011 Elsevier Ltd. All rights reserved.

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The Gedunin compound (C28H34O6) is a natural product extracted from Trichilia pallida that has shown a wide activity. The crystallographic structure shows two conformers in the asymmetric unit, which differ in a rotation of the furan group. To understand this molecular arrangement, the density functional calculations. Molecular Electrostatic Potential (MEP) and thermodynamic function calculation have been performed at the B3LYP/6-311++g(d,p) level. Both conformers were optimized and the agreement with the experimental structure was very good, making possible further theoretical analysis of the structure. The inter-conversion between two conformers depends on the energy barrier. This process is studied in the vacuum and shows two transition states with a low energetic barrier for a potential energy curve scanning rigid around furan group: 4.37 kcal/mol and 16.52 kcal/mol. As the first transition state has a notably lower energetic barrier, the preferred inter-conversion pathway between the conformers involves the first rather than the second transition state. Understanding this transition state in detail led us to perform its optimization, showing an energetic barrier around 3.66 kcal/mol. The negative free energy and low enthalpy confirm that the process is spontaneous and exothermic. The results show that this requirement makes the existence of the two conformers in the asymmetric unit possible. The structure of molecules in the asymmetric unit is better understood when the MEP is used on the interaction between molecules. For Gedunin, both molecules have shown MEP with well-defined regions, and this behavior contributes to the observed link between molecules and for the negative regions complementing positive regions of another molecule. (C) 2011 Elsevier B.V. All rights reserved.

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O Brasil é considerado o maior produtor de citros e o maior exportador de suco de laranja. Doenças de pós-colheita representam uma grande perda para a citricultura, sendo que para a exportação de frutos são rígidas as exigências com relação a isenção de resíduos químicos nos mesmos. Patógenos de importância em pós-colheita de citros incluem o Penicillium digitatum, agente causal do bolor-verde e o Colletotrichum gloeosporioides, agente causal da antracnose. Dada a importância econômica que representam estas doenças dos frutos cítricos, tanto em termos de comprometimento da qualidade e dificuldade de controle, a busca de alternativas adicionais que possam viabilizar a capacidade produtiva e garantir a obtenção de frutos com excelentes padrões de qualidade torna-se imprescindível. Portanto, estudou-se os efeitos dos extratos aquosos do flavedo de Citrus aurantifolia var. Tahiti, Lentinula edodes, Agaricus subrufescens (syn. Agaricus brasiliensis), albedo de Citrus sinensis var. Valência e do ácido jasmônico no controle póscolheita do bolor verde e da antracnose e na indução de resistência em frutos de laranjeira Valência (Citrus sinensis). Foi possível observar que o extrato aquoso do flavedo (C. aurantifolia) apresentou efeito inibitório sobre os patógenos, quando tratados em pós-colheita, em função da redução dos sintomas e esporulação. Porém, os extratos de albedo (C. sinensis), L. edodes, A. subrufescens e o ácido jasmônico não apresentaram efeitos sobre P. digitatum e C. gloeosporioides.

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Citrus leprosis, caused by Citrus leprosis virus C (CiLV-C), is currently considered the most important viral disease in the Brazilian citrus industry due to the high costs required for the chemical control of its vector, the mite Brevipalpus phoenicis. The pathogen induces a non-systemic infection and the disease is characterized by the appearance of localized lesions on citrus leaves, stems and fruits, premature fruit and leaf drop and dieback of stems. Attempts were made to promote in vitro expression of the putative cell-to-cell movement protein of CiLV-C in Escherichia coli and to produce a specific polyclonal antibody against this protein as a tool to investigate the virus-plant-vector relationship. The antibody reacted strongly with the homologous protein expressed in vitro by ELISA, but poorly with the native protein present in leaf lesion extracts from sweet orange caused by CiLV-C. Reactions from old lesions were more intense than those from young lesions. Western blot and in situ immunolocalization assays failed to detect the native protein. These results suggest low expression of the movement protein (MP) in host tissues. Moreover, it is possible that the conformation of the protein expressed in vitro and used to produce the antibody differs from that of the native MP, hindering a full recognition of the latter.

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A mancha preta dos citros (MPC), causada pelo fungo Guignardia citricarpa, produz lesões em frutos, os quais ficam depreciados para o mercado interno e os restringem para a exportação. O grande período de suscetibilidade dos frutos cítricos, em adição ao fato de G. citricarpa causar infecções latentes, dificulta o entendimento sobre o período de incubação da doença. O objetivo do trabalho foi determinar o período de incubação da MPC inoculando frutos de laranjeira 'Valência' em diferentes estádios fenológicos. Para a inoculação foram empregadas suspensões de conídios de G. citricarpa (10³, 10(4), 10(5) e 10(6) conídios mL-1) em diferentes diâmetros dos frutos (1,5; 2,0; 2,5; 3,0; 5,0 e 7,0 cm). O período de incubação da MPC para os diferentes diâmetros dos frutos inoculados apresentou uma relação polinomial negativa. Em frutos com até 3 cm de diâmetro o período de incubação médio foi superior a 200 dias, enquanto que em frutos com diâmetros superiores a 5 cm o período de incubação médio foi inferior a 84 dias. A MPC apresenta período de incubação variável dependente do estádio fenológico em que os frutos são infectados. A concentração de conídios de G. citricarpa, na infecção, não interfere no período de incubação da doença.

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Als paläoklimatische Archive können unter anderem Stalagmiten und Klappen von Ostrakoden herangezogen werden. Bisher gab es noch keine veröffentlichten Ergebnisse räumlich hochaufgelöster Spurenelementverteilungen in einzelnen Ostrakodenklappen. Das gleiche gilt für die Bestimmung radiogener Blei-Isotope in Stalagmiten. Um klimatische Prozesse vergangener Zeiten zu untersuchen, wurde eine neue LA-ICP-MS (Laserablations – Massenspektrometrie mit induktiv gekoppeltem Plasma) Technik für hochaufgelöste in-situ Messungen von Spurenelementen und Bleiisotopen entwickelt. rnrnZunächst wurden geeignete Materialien für die Kalibrierung der Technik untersucht; als Proben dienten die Silikatreferenzgläser BAM-S005-A und BAM-S005B der Bundesanstalt für Materialforschung und –prüfung (BAM). Die Homogenität dieser Referenzgläser wurde mit LA-ICP-MS und den anderen mikroanalytischen Methoden EPMA (Elektronenmikrosonde) und SIMS (Ionensonde) überprüft. Die Ergebnisse zeigten, dass alle Haupt- und die meisten Spurenelemente in beiden Gläsern selbst im Mikrometerbereich homogen verteilt sind. Ausnahmen sind einige Spurenelemente, wie Cs, Cl, Cr, Mo und Ni, die heterogen in den Gläsern verteilt sind. Die Hauptelementzusammensetzung von BAM-S005-A und BAM-S005-B wurde mit Hilfe der EPMA bestimmt, wobei die Ergebnisse die Referenzwerte des BAM-Zertifikats bestätigten. Mit Ausnahme von Sr, Ba, Ce und Pb, stimmten die LA-ICP-MS-Spurenelementwerte mit den zertifizierten Werten innerhalb der angegebenen Fehlergrenzen überein. Gründe für die Diskrepanz der vier oben erwähnten Elemente sind noch unklar, aber sind möglicherweise durch fehlerhafte Referenzwerte zu erklären. Zusätzlich wurden 22 Spurenelemente gemessen, deren Gehalte von BAM nicht zertifiziert wurden. Aufgrund dieser Untersuchungen konnte festgestellt werden, dass beide BAM-Gläser für mikroanalytische Anwendungen geeignet sind.rnrnUm neuartige paläoklimatische Proxies im Calcit von Ostrakoden aus tibetanischen Seesedimenten zu untersuchen, wurde die Spurenelementvariabilität in einzelnen Ostrakodenklappen durch eine neue LA-ICP-MS-Technik bestimmt. Klappen von Ostrakoden der drei Arten (Leucocytherella sinensis Huang, 1982, ?Leucocythere dorsotuberosa Huang, 1982 und ?L. dorsotuberosa f. postilirata sensu Pang, 1985) wurden aus zwei Sedimentkernen des Nam Co Sees auf dem Hochplateau von Tibet gewonnen. Zwei LA-ICP-MS-Varianten, Spot- bzw. Linienanalyse, wurden verwendet, um die Elementkonzentrationen der Spurenelemente Mg, Sr, Ba, U und die der Seltenen Erdelemente (SEE) in den Klappen einzelner Ostrakoden zu bestimmen. Die Ergebnisse zeigten, dass die Linienanalyse präzisere Daten als die Spotanalyse liefert und sie wurde daher vorgezogen. Signifikante Unterschiede in der Spurenelementzusammensetzung zwischen den verschiedenen Arten der Ostrakoden wurden nicht gefunden. Variationen der Elementverhältnisse Mg/Ca und Sr/Ca in den Klappen stimmen mit veröffentlichten Seenspiegelschwankungen während des Holozäns überein, was zeigt, dass Mg- und Sr-Messungen in den Ostrakoden zur Untersuchung paläohydrochemischer Prozesse in diesem Gebiet herangezogen werden kann. Die gute Korrelation, die in dieser Arbeit zwischen Ba/Ca und Sr/Ca gefunden wurde, ist ein Hinweis darauf, dass der Einbau von Ba und Sr in die Klappen durch den gleichen Mechanismus erfolgte. Eine mögliche Beziehung zwischen dem U/Ca-Verhältnis in den Ostrakoden und den Redoxbedingungen auf dem Boden des Sees in der Vergangenheit wird diskutiert. Relativ geringe und konstante La/Ca-Verhältnisse wurden festgestellt, deren Ursache möglicherweise entweder auf der SEE-Charakteristik des Seewassers, auf biologischen Prozessen in den Ostrakoden oder auf Kontamination von Fe-Mn und/oder organischen Substanzen beruhen. Weitere Untersuchungen an Proben aus diesem Gebiet, speziell Klappen von lebenden Ostrakoden, sind notwendig, um den Gehalt von Ba, U und den SEE in Ostrakoden als paläoklimatische Proxies von Umweltbedingungen zu verwenden.

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Dietary supplements (DS) are easily available and increasingly used, and adverse hepatic reactions have been reported following their intake. To critically review the literature on liver injury because of DSs, delineating patterns and mechanisms of injury and to increase the awareness towards this cause of acute and chronic liver damage. Studies and case reports on liver injury specifically because of DSs published between 1990 and 2010 were searched in the PubMed and EMBASE data bases using the terms 'dietary/nutritional supplements', 'adverse hepatic reactions', 'liver injury'; 'hepatitis', 'liver failure', 'vitamin A' and 'retinoids', and reviewed for yet unidentified publications. Significant liver injury was reported after intake of Herbalife and Hydroxycut products, tea extracts from Camellia sinensis, products containing usnic acid and high contents of vitamin A, anabolic steroids and others. No uniform pattern of hepatotoxicity has been identified and severity may range from asymptomatic elevations of serum liver enzymes to hepatic failure and death. Exact estimates on how frequent adverse hepatic reactions occur as a result of DSs cannot be provided. Liver injury from DSs mimicking other liver diseases is increasingly recognized. Measures to reduce risk include tighter regulation of their production and distribution and increased awareness of users and professionals of the potential risks.

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Background: Chai hu (Bupleuri radix), one of the most frequently used herbs in Chinese herbal medicine, has 3 major functions, depending on dosage and combination with other herbs. The aim of this study was to investigate how chai hu is prescribed in everyday practice in Switzerland, and whether these prescription patterns reflect its various applications. Methods: A random sample of 1,053 prescriptions was drawn from the database of Lian Chinaherb AG, Wollerau, Switzerland, and analyzed regarding the most frequently used classical formulas containing chai hu, daily dosages and combinations with other herbs. Results: 29.0% of all prescriptions contained chai hu, and 98.0% of these were in granular form. The most frequently used classical formulas were xiao yao san (‘rambling powder’), jia wei xiao yao san (‘augmented rambling powder’) and chai hu shu gan san (‘Bupleurum powder to spread the liver’). In more than half of the prescriptions, chai hu was combined with bai shao (Paeoniae Radix Alba), dang gui (Angelicae sinensis radix) or fu ling (Poria). 51.8% of the prescriptions contained a low daily dosage of chai hu, 24.9% a medium and 15.1% a high dosage. Conclusion: Chai hu was generally prescribed in classic combinations with other herbs and in a medium dosage. Due to the addition of supplementary herbs to classical formulas, its daily dose was often diminished from a high or medium dose to a low dose. This raises the question if chai hu would then still exert its desired function of, e.g., moving liver-qi in these prescriptions

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Introduction According to the Swiss Health Survey 2007, 1.7% of the adult population use traditional Chinese medicine (including Chinese herbal medicine, but excluding acupuncture). In contrast to conventional drugs, that contain single chemically defined substances, prescriptions of Chinese herbs are mixtures of up to 40 ingredients (parts of plants, fungi, animal substances and minerals). Originally they were taken in the form of decoctions, but nowadays granules are more popular. Medium daily dosages of granules range between 8 to 12g. In a recent work we identified the most commonly used Chinese herbs (all ingredients are referred to as herbs for reasons of simplicity) and classical formulas (mixtures). Here we present a short overview and the example of suan zao ren (Ziziphi Spinosae Semen), which is used in the treatment of insomnia and anxiety and contains saponins that have been shown to increase sleep in animal studies. Material and Methods A random sample of 1,053 prescriptions was drawn from the database of Lian Chinaherb AG, Switzerland, and analysed according to the most frequently used individual herbs and classical formulas. Cluster analysis (Jaccard similarity coefficient, complete linkage method) was applied to identify common combinations of herbs. Results The most frequently used herbs were dang gui (Angelicae Sinensis Radix), fu ling (Poria), bai shao (Paeoniae Radix Alba), and gan cao (Glycyrrhizae Radix et Rhizoma); the most frequently used classical formulas were gui pi tang (Restore the Spleen Decoction) and xiao yao san (Rambling Powder). The average number of herbs per prescription was 12.0, and the average daily dosage of granules was 8.7g. 74.3% of the prescriptions were for female, 24.8% for male patients. Suan zao ren was present in 14.2% of all prescriptions. These prescriptions contained on average 13.7 herbs, and the daily dosage of granules was 8.9g. Suan zao ren was more frequently prescribed by practitioners of non-Asian than of Asian origin but equally often for female and male patients. Cluster analysis grouped suan zao ren with yuan zhi (Polygalae Radix), bai zi ren (Platycladi Semen), sheng di huang (Rehmanniae Radix) and dan shen (Salviae Miltiorrhizae Radix et Rhizoma). Discussion Prescriptions including suan zao ren contained on average slightly more herbs than other prescriptions. This might be due to the fact that two of the three most popular classical formulas with suan zao ren are composed of 13 and 12 herbs with the possibility of adding more ingredients when necessary. Cluster analysis resulted in the clustering of suan zao ren with other herbs of the classical formula tian wang bu xin dan (Emperor of Heaven’s Special Pill to Tonify the Heart), indicating the use of suan zao ren for the treatment of insomnia and irritability. Unfortunately, the diagnoses of the patients were unavailable and thus correlations between use of suan zao ren and diseases could not be analysed.