RESUMEN
Hyperspectral analysis represents a powerful technique for diagnostics of morphological and chemical information from aboveground parts of the plants, but the real potential of the method in pre-screening of phenolics in leaves is still insufficiently explored. In this study, assessment of the sensitivity and reliability of non-invasive methods of various phenolic compounds, also analyzed by HPLC in chicory plants (Cichorium intybus L.) exposed to various color light pretreatments was done. The hyperspectral records in visible and near infrared (VNIR) spectra were recorded using a handheld spectrometer and relationships between the specific hyperspectral parameters and the contents of tested phenolic compounds in chicory leaves were analyzed. Moreover, the correlations between the hyperspectral parameters and related parameters derived from the multispectral fluorescence records were assessed to compare the sensitivity of both techniques. The results indicated a relatively high correlation of anthocyanin-related parameters (ARI, mARI, mACI indices) with the content of some of tested phenolic compounds (quercetin-3-gluconuride, isorhamnetine-3-gluconuride, etc.), as well as with fluorescence ANTH index. Similar trends were observed in flavonoid parameter based on the near infra-red spectral bands (700, 760 nm), which expressed a high correlation with chlorogenic acid. On the other hand, the most frequently used flavonoid (FLAVI) indices based on UV-to-blue band reflectance showed very weak correlations with phenolic compounds, as well as with fluorescence FLAV index. The detailed analysis of the correlation between reflectance and fluorescence flavonoid parameters has shown that the parameters based on spectral reflectance are sensitive to increase of UV-absorbing compounds from low to moderate values, but, unlike the fluorescence parameter, they are not useful to recognize a further increase from middle to high or very high contents. Thus, our results outlined the possibilities, but also the limits of the use of hyperspectral analysis for rapid screening phenolic content, providing a practical evidence towards more efficient production of bioactive compounds for pharmaceutical or nutraceutical use.
Asunto(s)
Cichorium intybus/química , Luz , Fenoles/análisis , Cichorium intybus/efectos de la radiación , Flavonoides/análisis , Hojas de la Planta/química , Hojas de la Planta/efectos de la radiación , Reproducibilidad de los ResultadosRESUMEN
The presence of arsenic (As) in groundwater is a major problem in several parts of Latin America. In the present work, non-destructive approaches to monitor the effects of As on plants of Cichorium intybus, an herbaceous Asteraceae, were explored. In this sense, the effects of As at different levels of water and radiation were evaluated on these crops. Plants were grown in a greenhouse, watered daily with As solutions and exposed to different water and/or light conditions for four months, using a three-factor (As, water, radiation) and two-level resource (As vs non As, field capacity vs half-field capacity condition, light vs shade condition) factorial design. The parameters most affected by this treatment were the area under the first derivative of the reflectance spectrum in the blue region, chlorophyll concentration, the Fred/Ffar-red fluorescence ratio and the quantum yield for the photophysical decay. These changes indicated the ability of this plant species to be a biomonitor for the presence of arsenic in irrigation water. Interestingly, it was further proved in this work that the biomonitoring capacity was enhanced in the presence of sunlight.
Asunto(s)
Riego Agrícola/métodos , Arsénico/toxicidad , Cichorium intybus/fisiología , Monitoreo del Ambiente/métodos , Luz Solar/efectos adversos , Cichorium intybus/efectos de los fármacos , Cichorium intybus/efectos de la radiación , Clorofila/química , Fluorescencia , Agua/químicaRESUMEN
BACKGROUND: Chicory stems, appreciated both raw and cooked, represent a nutritious and refined food. In this study the effects on the quality of stems cooked by conventional (boiling, steaming and microwaving) and innovative (sous vide) methods were analysed. Several physical, chemical and sensory traits were compared using two local varieties (Galatina and Molfettese) of southern Italy (Puglia region). RESULTS: Independently of the variety, the sous vide method did not significantly affect (redness, yellowness and hue angle) or had the least impact on (lightness and total colour difference) quality parameters among the four methods as compared with the raw product. Following sensory analysis, the sous vide product always showed the highest score among the cooking methods. Moreover, this innovative method did not affect total phenol (TP) content and antioxidant activity (AA) compared with uncooked stems of both varieties. Microwaving increased TP content and AA (though associated with higher weight loss), while different responses depending on the chicory variety were observed after boiling and steaming. CONCLUSION: The results indicate the sous vide technique as optimal to preserve several traits, including organoleptic ones, for the quality of cook-chilled chicory stems. They also provide product-specific information usually required for cooking process strategies in the industrial sector of ready-to-eat vegetables.