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1.
Front Plant Sci ; 13: 1004069, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684789

RESUMO

Among the Mediterranean horticultural landraces, garlic is one of the crops most threatened by genetic erosion. Due to its sexual sterility and to the incidence of seed-borne diseases, historical varieties have been widely replaced by commercial cultivars. In Catalonia, despite the historical relevance of the crop, solely the Belltall garlic landrace is cultivated for commercial purposes. To assess the genotypic and phenotypic diversity within the Belltall garlic, we evaluated sixteen local accessions and five recognized traditional and modern varieties as controls. Genetic analysis with SSR and InDel markers showed low genetic diversity within the Belltall population, grouping modern and traditional varieties separately. Farmers and consumers were involved in the definition of the landrace ideotype and classified the materials by means of projective mapping. Scant phenotypic diversity was found within the Belltall landrace, which is characterized by its color profile and the small size of bulb and cloves. The Belltall landrace grown outside its area of origin lost the distinctive quality signals that differentiate the landrace from the commercial cultivars (clove appearance), indicating that the high quality of the landrace is under genotype-by-environment effects (i.e. local adaptation). Moreover, the size of the Belltall sowing clove had a strong effect on the harvested bulb size. Our research represents a case study for the description of the variability within garlic landraces and an approach to quantify the phenomenon of local adaptation that currently drives their conservation.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 180: 119-126, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28284157

RESUMO

Even when the feasibility of using near infrared (NIR) spectroscopy combined with partial least squares (PLS) regression for prediction of physico-chemical properties of biodiesel/diesel blends has been widely demonstrated, inclusion in the calibration sets of the whole variability of diesel samples from diverse production origins still remains as an important challenge when constructing the models. This work presents a useful strategy for the systematic selection of calibration sets of samples of biodiesel/diesel blends from diverse origins, based on a binary code, principal components analysis (PCA) and the Kennard-Stones algorithm. Results show that using this methodology the models can keep their robustness over time. PLS calculations have been done using a specialized chemometric software as well as the software of the NIR instrument installed in plant, and both produced RMSEP under reproducibility values of the reference methods. The models have been proved for on-line simultaneous determination of seven properties: density, cetane index, fatty acid methyl esters (FAME) content, cloud point, boiling point at 95% of recovery, flash point and sulphur.


Assuntos
Biocombustíveis/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Análise dos Mínimos Quadrados , Petróleo/análise , Análise de Componente Principal , Padrões de Referência , Reprodutibilidade dos Testes , Espectroscopia de Luz Próxima ao Infravermelho/normas
3.
J Pharm Sci ; 103(9): 2839-2846, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24665039

RESUMO

Evaluation of freeze-dried biopharmaceutical formulations requires careful analysis of multiple quality attributes. The aim of this study was to evaluate the use of near-infrared (NIR) imaging for fast analysis of water content and related physical properties in freeze-dried formulations. Model formulations were freeze-dried in well plates. Samples were imaged with a NIR hyperspectral camera after freeze-drying and upon storage. On the basis of Karl Fischer titration reference values, a univariate quantification model was constructed and used to visualize the distribution of water within freeze-dried samples. Differences observed between samples stored at 11% and 43% relative humidity (RH) were found to be related to the amount of amorphous component in the sample. When stored at 43% RH, the moisture content in samples with high sucrose content increased within 2 days and some degree of localized drying was observed within the samples after 3 days of storage. Further investigations with X-ray powder diffraction confirmed this local drying to be related to crystallization of sucrose. The combination of fast analysis of water content and spatial solid-state information makes NIR imaging a powerful tool for formulation development of freeze-dried samples.


Assuntos
Preparações Farmacêuticas/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Água/química , Química Farmacêutica/métodos , Cristalização/métodos , Dessecação/métodos , Liofilização/métodos , Umidade , Pós/química , Sacarose/química , Difração de Raios X/métodos
4.
J Pharm Anal ; 2(2): 90-97, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29403727

RESUMO

The growing interest of the pharmaceutical industry in Near Infrared-Chemical Imaging (NIR-CI) is a result of its high usefulness for quality control analyses of drugs throughout their production process (particularly of its non-destructive nature and expeditious data acquisition). In this work, the concentration and distribution of the major and minor components of pharmaceutical tablets are determined and the spatial distribution from the internal and external sides has been obtained. In addition, the same NIR-CI allowed the coating thickness and its surface distribution to be quantified. Images were processed to extract the target data and calibration models constructed using the Partial Least Squares (PLS) algorithms. The concentrations of Active Pharmaceutical Ingredient (API) and excipients obtained for uncoated cores were essentially identical to the nominal values of the pharmaceutical formulation. But the predictive ability of the calibration models applied to the coated tablets decreased as the coating thickness increased.

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