RESUMEN
Although used in in vitro culture to boost secondary metabolite production, UV-B radiation can seriously affect plant growth if not properly dosed. Rosemary callus can be used as an important source of effective ingredients in the food and medicine industry. To balance the positive and negative effects of UV-B on rosmary callus, this study investigated the effects of melatonin on rosemary callus under UV-B radiation. The results showed that melatonin improved rosemary callus growth, with fresh weight and dry weight increased by 15.81% and 8.30%, respectively. The addition of 100 µM melatonin increased antioxidant enzyme activity and NO content in rosemary callus. At the same time, melatonin also significantly reduced membrane lipid damage and H2O2 accumulation in rosemary callus under UV-B stress, with malondialdehyde (MDA) and H2O2 contents reduced by 13.03% and 14.55%, respectively. In addition, melatonin increased the total phenol and rosmarinic acid contents in rosemary callus by 19% and 54%, respectively. Melatonin significantly improved the antioxidant activity of the extracts from rosemary callus. These results suggest that exogenous melatonin can alleviate the adverse effects of UV-B stress on rosemary callus by promoting NO accumulation while further enhancing phenolic accumulation and biological activity.
Asunto(s)
Antioxidantes , Peróxido de Hidrógeno , Melatonina , Fenoles , Rosmarinus , Rayos Ultravioleta , Melatonina/farmacología , Melatonina/metabolismo , Rosmarinus/metabolismo , Rosmarinus/efectos de los fármacos , Rosmarinus/efectos de la radiación , Antioxidantes/metabolismo , Fenoles/metabolismo , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Estrés Fisiológico/efectos de la radiación , Estrés Fisiológico/efectos de los fármacos , Ácido Rosmarínico , Cinamatos/metabolismo , Cinamatos/farmacología , Depsidos/metabolismoRESUMEN
The effect of different hydrodistillation pretreatments, namely, reflux extraction, reflux extraction with the addition of cell wall-degrading enzymes, and ultrasound, on the yield and chemical composition of essential oils of sage, bay laurel, and rosemary was examined. All pretreatments improved essential oil yield compared to no-pretreatment control (40-64% yield increase), while the oil quality remained mostly unchanged (as shown by statistical analysis of GC-MS results). However, enzyme-assisted reflux extraction pretreatment did not significantly outperform reflux extraction (no-enzyme control), suggesting that the observed yield increase was mostly a consequence of reflux extraction and enzymatic activity had only a minute effect. Thus, we show that ultrasound and reflux extraction pretreatments are beneficial in the production of essential oils of selected Mediterranean plants, but the application of enzymes has to be carefully re-evaluated.
Asunto(s)
Aceites Volátiles/química , Hojas de la Planta/química , Aceites de Plantas/aislamiento & purificación , Rosmarinus/química , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/efectos de la radiación , Hojas de la Planta/efectos de la radiación , Aceites de Plantas/química , Aceites de Plantas/efectos de la radiación , Rosmarinus/efectos de la radiación , Ondas UltrasónicasRESUMEN
Thyme (Thymus vidgaris L.), rosemary (Rosmarinus officinalis L.), black pepper (Piper nigrum L.) and cumin (Cuminum cyminum L.) in ground form were packaged in either air or 100% N2 and γ-irradiated at 3 different irradiation levels (7kGy, 12kGy, 17kGy). Total viable bacterial count, yeast and mould count, colour, essential oil yield and essential oil composition were determined. Microbial load was not detectable after 12kGy irradiation of all samples. Irradiation resulted in significant changes in colour values of rosemary and black pepper. The discolouration of the irradiated black pepper was lower in modified atmosphere packaging (MAP) compared to air packaging. Essential oil yield of irradiated black pepper and cumin was lower in air packaging compared to MAP. Gamma-irradiation generally decreased monoterpenes and increased oxygenated compounds, but the effect was lower in MAP. Overall, spices should be irradiated under an O2-free atmosphere to minimise quality deterioration.
Asunto(s)
Cuminum/efectos de la radiación , Irradiación de Alimentos/métodos , Piper nigrum/efectos de la radiación , Rosmarinus/efectos de la radiación , Especias/análisis , Especias/efectos de la radiación , Thymus (Planta)/efectos de la radiación , Cuminum/química , Cuminum/microbiología , Embalaje de Alimentos , Rayos gamma , Piper nigrum/química , Piper nigrum/microbiología , Control de Calidad , Rosmarinus/química , Rosmarinus/microbiología , Especias/microbiología , Thymus (Planta)/química , Thymus (Planta)/microbiologíaRESUMEN
The use of composted biosolids as an amendment for forest regeneration in degraded ecosystems is growing since sewage-sludge dumping has been banned in the European Community. Its consequences on plant terpenes are however unknown. Terpene emissions of both Rosmarinus officinalis (a terpene-storing species) and Quercus coccifera (a non-storing species) and terpene content of the former, were studied after a middle-term exposure to compost at intermediate (50tha(-1): D50) and high (100tha(-1): D100) compost rates, in a seven-year-old post-fire shrubland ecosystem. Some chlorophyll fluorescence parameters (Fv/Fm, ETR, Phi(PSII)), soil and plant enrichment in phosphorus (P) and nitrogen (N) were monitored simultaneously in amended and non-amended plots in order to establish what factors were responsible for possible compost effect on terpenes. Compost affected all studied parameters with the exception of Fv/Fm and terpene content. For both species, mono- and sesquiterpene basal emissions were intensified solely under D50 plots. On the contrary leaf P, leaf N levels reached in D50 were partly responsible of terpene changes, suggesting that optimal N conditions occurred therein. N also affected ETR and Phi(PSII) which were, in turn, robustly correlated to terpene emissions. These results imply that emissions of terpene-storing and non-storing species were under nitrogen and chlorophyll fluorescence control, and that a correct management of compost rates applied on soil may modify terpene emission rate of plants, which in turn has consequences in air quality and plant defense mechanisms.
Asunto(s)
Clorofila/metabolismo , Fluorescencia , Nitrógeno/metabolismo , Quercus/química , Quercus/metabolismo , Rosmarinus/química , Rosmarinus/metabolismo , Suelo , Luz , Fósforo/metabolismo , Fotosíntesis , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de la radiación , Quercus/efectos de la radiación , Rosmarinus/efectos de la radiación , Terpenos/metabolismo , VolatilizaciónRESUMEN
The aim of this study was to examine the effect of ultrasound on the solvent extraction of anti-oxidants from the rosemary herb and to scale up the ultrasonic extraction process. The anti-oxidants of interest were identified using HPLC. Results indicated that, compared with conventional solvent extraction, the use of ultrasound gives a more effective extraction at lower temperatures with less dependence on the extraction solvent employed and that scale up of the process is possible.
Asunto(s)
Antioxidantes/química , Antioxidantes/efectos de la radiación , Rosmarinus/química , Rosmarinus/efectos de la radiación , Ultrasonido , Abietanos/química , Abietanos/efectos de la radiación , Compuestos de Bifenilo , Cinamatos/química , Cinamatos/efectos de la radiación , Depsidos/química , Depsidos/efectos de la radiación , Etanol/química , Metanol/química , Picratos , Extractos Vegetales/química , Extractos Vegetales/efectos de la radiación , Hojas de la Planta/química , Hojas de la Planta/efectos de la radiación , Solventes , Espectrofotometría Ultravioleta , Ácido RosmarínicoRESUMEN
Nine spice and aromatic herb samples (i.e., basil, bird pepper, black pepper, cinnamon, nutmeg, oregano, parsley, rosemary, and sage) were gamma-irradiated at a dose of 10 kGy according to commercial practices. The effects of the disinfection treatment on the content of organic radicals and some nutrients (namely, vitamin C and carotenoids) in the samples were investigated by chromatographic and spectroscopic techniques. Irradiation resulted in a general increase of quinone radical content in all of the investigated samples, as revealed by electron paramagnetic resonance spectroscopy. The fate of these radicals after storage for 3 months was also investigated. The cellulose radical was clearly observed in a few samples. Significant losses of total ascorbate were found for black pepper, cinnamon, nutmeg, oregano, and sage, whereas a significant decrease of carotenoids content was observed for cinnamon, oregano, parsley, rosemary, bird pepper, and sage.