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Anthocyanin stability: a chemometrical approach IPB - Escola Superior Agrária
Cabrita, Luís; Fossen, Torgils; Flåten, Geir R.; Andersen, Øyvind M..
The stability of cyanidin 3-glucoside towards five different factors (pH, anthocyanin concentration, sodium chloride concentration, ascorbic acid concentration, Oxygen) was studied during 60 days storage at room temperature using a 2^4-1 reduced factorial design. The influence of each individual parameter on anthocyanin stability was found to vary as a function of time. Sodium chloride and ascorbic acid were, respectively, the variables most contributing to and against anthocyanin stability. Results suggest there may be some degree of interaction between anthocyanin/ascorbic acid, and between pH/Oxygen, affecting anthocyanin degradation.
Tipo: ConferenceObject Palavras-chave: Anthocyanins; Colour stability; HPLC; UV-Vis; Chemometrics; Reduced factorial design.
Ano: 2002 URL: http://hdl.handle.net/10198/3210
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Assessment of physicochemical, textural and microbiological properties of brazilian white mold surface-ripened cheeses: a technological approach Ciência Rural
Pereira,Antonio Carlos Prestes; Judacewski,Priscila; Coelho,Gabriel; Salem,Renata Dinnies Santos; Marinho,Marina Tolentino; Alberti,Aline; Zielinski,Acácio Antonio Ferreira; Demiate,Ivo Mottin; Nogueira,Alessandro.
ABSTRACT: There are no specific technical regulations regarding the identity and quality of white mold surface-ripened cheeses in Brazil. These cheeses are sold both whole (Camembert-type) and in wedges (Brie-type). The aim of the study was to evaluate the physical and chemical properties; technological parameters and microbiological safety of 20 whole cheeses (Camembert-type) and 16 cheese wedges (Brie-type) produced in Brazil. Samples showed a wide range in sodium (91.0-731.0 mg/100 g, cheeses wedges) and calcium (238.0-1100.0 mg/100g, whole cheeses) contents. The cheese groups presented no significant differences in relation to the majority of the analyzed parameters. Listeria monocytogenes was reported in 5% of the whole cheese samples. The other...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Cheese quality; Chemometrics; Camembert-type cheese; Brie-type cheese.
Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000100752
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Best conditions for biodegradation of diesel oil by chemometric tools BJM
Kaczorek,Ewa; Bielicka-Daszkiewicz,Katarzyna; Héberger,Károly; Kemény,Sándor; Olszanowski,Andrzej; Voelkel,Adam.
Diesel oil biodegradation by different bacteria-yeast-rhamnolipids consortia was tested. Chromatographic analysis of post-biodegradation residue was completed with chemometric tools (ANOVA, and a novel ranking procedure based on the sum of ranking differences). These tools were used in the selection of the most effective systems. The best results of aliphatic fractions of diesel oil biodegradation were observed for a yeast consortia with Aeromonas hydrophila KR4. For these systems the positive effect of rhamnolipids on hydrocarbon biodegradation was observed. However, rhamnolipids addition did not always have a positive influence on the biodegradation process (e.g. in case of yeast consortia with Stenotrophomonas maltophila KR7). Moreover, particular...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biodegradation; Chemometrics; Systems ranking; Variance analysis.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822014000100017
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Brachiaria plantaginea as a potential (new) source of shikimic acid: quantification by NIR and PLS regression. Repositório Alice
COSTA, M. C. A.; MATALLO, M. B.; FERREIRA, M. M. C.; QUEIROZ, S. C. do N. de; ALMEIDA, S. D. B.; FRANCO, D. A. S..
Abstract: Shikimic acid is a natural organic compound produced in the biochemical pathways of eukaryotic organisms and is generally utilized as a starting material of the antiviral drug Oseltamivir (Tamiflu®). This study shows the results of shikimic acid accumulation in Brachiaria plantaginea, an abundant, grassy plant found in Brazil and other countries in Africa and America, after glyphosate spraying at three different doses. B. plantaginea plants harvested after 6 days of exposure to the herbicide showed that shikimic acid accumulation increased by 345%, on average, compared to unsprayed plants. The combination of near infrared spectroscopy and multivariate analysis using partial least square regression was applied for the quantification of shikimic...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: NIR spectroscopy; PLS regression; Brachiaria plantaginea; Gramínea; Shikimic acid; Chemometrics.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1066054
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Chalcones and N-acylhydrazones: direct analogues? Exploratory data analysis applied to potential novel antileishmanial agents BJPS
Rando,Daniela Gonçalves; Giarolla,Jeanine; Pasqualoto,Kerly Fernanda Mesquita; Ferreira,Elizabeth Igne.
Leishmaniasis is an important health and social problem for which there is limited effective therapy. Chalcones and N-acylhydrazones have been studied as promising antileishmanial agents in enzymatic inhibition and in vitro assays. Since these chemical classes of compounds also resemble each other structurally, it would be useful to investigate whether they share direct analogy. Exploratory data analysis was applied to a library of chalcones and nitrated N-acylhydrazones assayed against Leishmania donovani to investigate their similarity. Under the conditions applied in the present study, the two classes did not present functional or structural analogy.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chalcones; N-acylhydrazones; Antileishmanial agents; Leishmaniasis; Chemometrics.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-82502010000200019
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Characterization and classification of pequi trees (Caryocar brasiliense Camb.) based on the profile of volatile constituents using headspace solid-phase microextraction - gas chromatography - mass spectrometry and multivariate analysis Ciênc. Tecnol. Aliment.
Belo,Renata França Cassimiro; Augusti,Rodinei; Lopes,Paulo Sérgio Nascimento; Junqueira,Roberto Gonçalves.
In order to determine the variability of pequi tree (Caryocar brasiliense Camb.) populations, volatile compounds from fruits of eighteen trees representing five populations were extracted by headspace solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. Seventy-seven compounds were identified, including esters, hydrocarbons, terpenoids, ketones, lactones, and alcohols. Several compounds had not been previously reported in the pequi fruit. The amount of total volatile compounds and the individual compound contents varied between plants. The volatile profile enabled the differentiation of all of the eighteen plants, indicating that there is a characteristic profile in terms of their origin. The use of Principal Component Analysis...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chemometrics; Biodiversity; Cerrado native fruit.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612013000500018
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Chemo-characterization and optimization of macro and micro nutrients for exopolysaccharides and mycelia growth in pleurotus tuberregium (RUMPH, EX FR) Ciênc. Tecnol. Aliment.
MOYIB,Oluwasayo Kehinde; ADEJOYE,Oluseyi Damilola; SODIQUE,Folake Ramat.
Abstract Exoploysaccharides are potential nutraceutic, probiotic, phamarceutic and cosmesceutic natural products in fungi. Pleurotus tuberregium is an underutilized tropical fungus that is useful as food with recent reports of pharmacological activities. The present study evaluated and characterized environmental conditions and nutrients for optimal P. tuberregium mycelia growth (PtMG) and exopolysaccharides (PtEPS) production using batch culturing and diverse chemometric methods, respectively. Rank-sum analysis categorized the assessed conditions and nutrients into six stimulatory classes and most suitable nutrients and conditions for PtMG and PtEPS were co-identified with analysis of variance. Glucose, yeast, sodium chloride (NaCl) and tricalcium...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chemometrics; Environmental condition and nutrients; P. tuberregium exopolysaccharides (PtEPS); P. tuberregium mycelia growth (PtMG); Stimulant.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612019000200286
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Chemometric characterization of three varietal olive oils (Cvs. cobrancosa, madural and verdeal Transmontana) extracted from olives with different maturation indices. IPB - Escola Superior Agrária
Matos, L.C.; Cunha, S.C.; Amaral, J.S.; Pereira, J.A.; Andrade, P.B.; Seabra, R.M.; Oliveira, M.B.P.P..
This paper evaluates the usefulness of three chemical parameters (compositions on tocopherols, sterols and fatty acids) as a tool to discriminate three varietal olive oils (Cvs. Cobrançosa, Madural and Verdeal Transmontana), which are permitted cultivars for the production of ‘‘Trás-os-Montes olive oil’’, a Portuguese protected designation of origin (PDO) product. The olives were collected during the year crop 2000/2001 from the same orchard, in order to eliminate the geographical and climatic influences. Lots with different maturation indices were prepared to allow the evaluation of the ripening stage on the characteristics of varietal olive oils produced from each cultivar. Statistical methods such as multivariate analysis of variance (MANOVA), principal...
Tipo: Article Palavras-chave: Portuguese virgin olive oil; Ripening; Chemometrics; PDO.
Ano: 2007 URL: http://hdl.handle.net/10198/754
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Composição de metabólitos primários e perfil de compostos voláteis dos frutos deetnovariedades de gabiroba (Campomanesia xanthocarpa Berg) com ocorrência na floresta nacional da Região Sul do Brasil. Repositório Alice
PAZ, S. A..
bitstream/item/220607/1/TS2020-014-dis-SAP.pdf
Tipo: Tese/dissertação (ALICE) Palavras-chave: Gabiroba; Etnovariedades; RMN; Compostos voláteis; Quimiometria; Ethnovarieties; NMR; Myrtaceae; Aroma; Chemometrics; Volatile compounds.
Ano: 2020 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1129542
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Compostos fenólicos em pedúnculos de clones de cajueiro e a relação com a adstringência e suas subqualidades. Repositório Alice
BRAGA, D. C..
A adstringência é uma sensação tátil, gerada pela redução da lubrificação na cavidade oral, comumente causada pela interação de compostos fenólicos com as proteínas salivares. No pedúnculo do cajueiro, a adstringência é o principal problema que limita a sua aceitabilidade, sendo um dos maiores obstáculos para a expansão do mercado. Este trabalho buscou caracterizar o perfil sensorial e o perfil de compostos fenólicos de pedúnculos de cajueiro, e por meio de quimiometria, correlaciona-los buscando os possíveis marcadores químicos da adstringência do caju. Foram analisados pedúnculos de nove clones da safra 2017. A análise sensorial foi baseada em uma análise descritiva de provadores previamente selecionados e treinados, registrando a intensidade dos...
Tipo: Tese/dissertação (ALICE) Palavras-chave: Anacardium occidentale L; UPLC; Análise sensorial; Chemometrics.
Ano: 2019 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1106803
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Digital Soil Mapping of Soil Properties in the “Mar de Morros” Environment Using Spectral Data Rev. Bras. Ciênc. Solo
Campbell,Patrícia Morais da Matta; Fernandes Filho,Elpídio Inácio; Francelino,Márcio Rocha; Demattê,José Alexandre Melo; Pereira,Marcos Gervasio; and,Clécia Cristina Barbosa Guimarães; Pinto,Luiz Alberto da Silva Rodrigues.
ABSTRACT Quantification of soil properties is essential for better understanding of the environment and better soil management. The conventional techniques of laboratory analysis are sometimes costly and detrimental to the environment. Thus, development of new techniques for soil analysis that do not generate residues, such as spectroscopy, is increasingly necessary as a viable way to estimate a wide range of soil properties. The objective of this study was to predict the levels of organic carbon (OC), clay, and extractable phosphorus (P), from the spectral responses of soil samples in the visible and near infrared (Vis-NIR), medium infrared (MIR), and Vis-NIR-MIR using different preprocessing methods combined with five prediction models. Soil samples were...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Spectral analysis; Reflectance; Chemometrics.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100314
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Espectroscopia no infravermelho próximo para estimativa da densidade básica de madeiras de Pinus. Repositório Alice
LAZZAROTTO, M.; NETIPANYJ, R. R.; MAGALHAES, W. L. E.; AGUIAR, A. V. de.
A densidade básica é uma das mais importantes características das madeiras e usada em programas de melhoramento genético florestal. Este trabalho teve o objetivo de construir um modelo de predição da densidade básica de madeiras de Pinus maximinoi e Pinus tecunumanii, usando a espectroscopia no infravermelho próximo e análise estatística multivariada. O modelo foi construído com 54 amostras usando mínimos múltiplos quadrados (PLS) como tratamento estatístico (com alisamento do sinal, variação normal padrão SNV e primeira derivada). A curva de calibração apresentou coeficiente de determinação (R2) de 0,94 e erro de validação cruzada de aproximadamente 30 kg m-3 para uma densidade básica média de 517 kg m-3. Este modelo foi validado externamente com 27...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: NIR; Quimiometria; Densidade básica; Regressão PLS; PLS regression; Madeira; Qualidade; Pinus; Espécie exótica; Near-infrared spectroscopy; Wood quality; Wood density; Chemometrics.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1062623
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Evaluation of phenolic compounds content and in vitro antioxidant activity of red wines produced from Vitis labrusca grapes Ciênc. Tecnol. Aliment.
Lima,Daniel Braga de; Agustini,Bruna Carla; Silva,Eliz Guimarães da; Gaensly,Fernanda; Cordeiro,Rodrigo Becker; Fávero,Maria Luiza Drechsel; Brand,Debora; Maraschin,Marcelo; Bonfim,Tania Maria Bordin.
Wine production in the northern Curitiba, Paraná, Brazil, specifically the communes of Colombo and Almirante Tamandaré, is based mainly on the utilization of Vitis labrusca grapes var. Bordô (Ives). Total sugar content, pH, and total acidity were analyzed in red wine samples from 2007 and 2008 vintages following official methods of analysis. Moreover, total phenolic, flavonoid, and tannin contents were analyzed by colorimetric methodologies and the antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical methodology. Phenolic compounds were identified by high performance liquid chromatography. The total phenolic content of wine samples presented concentrations varying between 1582.35 and 2896.08 mg gallic acid.L-1 since...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Rural; Winery; Chemometrics; Common wine; HPLC; Viniculture.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612011000300038
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Genotype evaluation of cowpea seeds (Vigna unguiculata) using 1H qNMR combined with exploratory tools and solid-state NMR. Repositório Alice
ALVES FILHO, E. G.; SILVA, L. M. A. e; TEOFILO, E. M.; LARSEN, F. H.; BRITO, E. S. de.
bitstream/item/167028/1/ART17019.pdf
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Genótipo de sementes de caupi; Oligosacarídeos; NMR; Chemometria; CP-MAS; SP/MAS; Cowpea seeds genotype; Chemometrics; Oligosaccharides.
Ano: 2017 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1073517
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Grapevine leaf water potential based upon near infrared spectroscopy Scientia Agricola
Santos,Antonio Odair; Kaye,Oren.
Leaf water potential is a measure commonly used to describe crop water status and water stress dynamics. The established method for determining leaf water potential using a pressure chamber is cumbersome and subject to operator error as well as time/temperature limitations. These limitations prohibit the intensive sampling required to support proactive water management of commercial crops, including vineyards. Particular for grapevines there is need for faster, more precise and more reliable tools for determining leaf water potential in the field. Portable Near-infrared spectroscopy and multivariate data analysis were applied for the modeling and prediction of leaf water potential in grapevines. For field-grown wine grapes the most significant and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: PLS; Irrigation; Spectrometry; Chemometrics.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000300001
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Green method by diffuse reflectance infrared spectroscopy and spectral region selection for the quantification of sulphamethoxazole and trimethoprim in pharmaceutical formulations Anais da ABC (AABC)
Silva,Fabiana E.B. da; Flores,Érico M.M.; Parisotto,Graciele; Müller,Edson I.; Ferrão,Marco F..
An alternative method for the quantification of sulphametoxazole (SMZ) and trimethoprim (TMP) using diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS) and partial least square regression (PLS) was developed. Interval Partial Least Square (iPLS) and Synergy Partial Least Square (siPLS) were applied to select a spectral range that provided the lowest prediction error in comparison to the full-spectrum model. Fifteen commercial tablet formulations and forty-nine synthetic samples were used. The ranges of concentration considered were 400 to 900 mg g-1SMZ and 80 to 240 mg g-1 TMP. Spectral data were recorded between 600 and 4000 cm-1 with a 4 cm-1 resolution by Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). The proposed...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chemometrics; Diffuse reflectance infrared Fourier transform spectroscopy; Green analytical method; High performance liquid chromatography; Interval partial least squares (iPLS); Synergy partial least squares (siPLS).
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652016000100001
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High-resolution prediction of organic matter concentration with hyperspectral imaging on a sediment core ArchiMer
Jacq, Kévin; Perrette, Yves; Fanget, Bernard; Sabatier, Pierre; Coquin, Didier; Martinez-lamas, Ruth; Debret, Maxime; Arnaud, Fabien.
In the case of environmental samples, the use of a chemometrics-based prediction model is highly challenging because of the difficulty in experimentally creating a well-ranged reference sample set. In this study, we present a methodology using short wave infrared hyperspectral imaging to create a partial least squares regression model on a cored sediment sample. It was applied to a sediment core of the well-known Lake Bourget (Western Alps, France) to develop and validate a model for downcore high resolution LOI550 measurements used as a proxy of the organic matter. In lake and marine sediment, the organic matter content is widely used, for example, to reconstruct carbon flux variations through time. Organic matter analysis through routine analysis methods...
Tipo: Text Palavras-chave: Hyperspectral imaging; Chemometrics; Near-infrared spectroscopy; High resolution analysis; Organic matter.
Ano: 2019 URL: https://archimer.ifremer.fr/doc/00478/59018/61636.pdf
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Near-Infrared Spectroscopy for Non-Destructive Prediction of Maturity and Eating Quality of ‘Carabao’ Mango (Mangifera indica L.) Fruit CIGR Journal
Polinar, Yvonne Q.; Yaptenco, Kevin Fernandez; Peralta, Engelbert K.; Agravante, Josephine U..
Near-infrared (NIR) spectroscopy was assessed in predicting maturity and eating quality of ‘Carabao’ mango fruit. A total of 1,200 fruits were harvested at the green stage at four different harvest dates [100, 110, 120 and 125 days after flower induction (DAFI)]. Fruits were scanned at the green and table-ripe stage (TRS) using NIR reflectance spectroscopy. The fruits were then measured destructively for the determination of dry matter (DM) content at the green stage, total soluble solids (TSS) and sensory attributes at the TRS. The best calibration models were achieved using partial least square regression (PLSR) analysis for predicting DM, TSS and maturity in the short wavelength region of 700 - 990 nm at 2-nm increment. Principal component...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Agricultural / biosystems engineering; Chemometrics; Horticulture Near-infrared; Mango; Sweetness; Maturity; Eating quality; Philippines.
Ano: 2019 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/5152
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NMR and LC-MS assessment of compound variability of common bean (Phaseolus vulgaris) stored under controlled atmosphere. Repositório Alice
COELHO, S. R. M.; ALVES FILHO, E. DE G.; SILVA, L. M. A. e; BISCHOFF, T. Z.; RIBEIRO, P. R. V.; ZOCOLO, G. J.; CANUTO, K. M.; BASSINELLO, P. Z.; BRITO, E. S. de.
bitstream/item/208901/1/ART19114.pdf
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Metabolitos primários; Metabólitos secundários; Quimiometria; Primary metabolites; Phaseolus Vulgaris; Phaseolus vulgaris endornavirus; Pea early-browning virus; Chemometrics.
Ano: 2020 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1118833
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Pattern recognition applied applied to mineral characterization of Brazilian coffees and sugar-cane spirits. Repositório Alice
FERNANDES, A. P.; SANTOS, M. C.; LEMOS, S. G.; FERREIRA, M. M. C.; NOGUEIRA, A. R. de A.; NÓBREGA, J. A..
2005
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Coffee; Sugar-cane spirit; Chemometrics; Pattern recognition.
Ano: 2005 URL: http://www.alice.cnptia.embrapa.br/handle/doc/47045
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