RESUMEN
BACKGROUND: Nigella sativa L (NS) is a powerful antioxidant and medicinal plant with many therapeutic applications particularly in traditional medicine for respiratory, gastrointestinal, rheumatic, and inflammatory disorders, as well as cancer. OBJECTIVE: The aim of this study is to extract the active ingredients from the Moroccan Nigella sativa L and determine its antioxidant properties. We hypothesize that the separation of the compounds from Nigella sativa L has either a positive or negative effect on antioxidants. To study this, we explored different methods to simultaneously extract and separate compounds from Nigella sativa L and performed antioxidant tests (ß-carotene and DPPH) for all collected fractions. METHODS: Nigella sativa L was hot-extracted by Soxhlet and mother extracts and was separated using silica column chromatography with adequate eluents. Qualitative phytochemical tests to determine the chemical families in Nigella sativa L seeds were performed on the fractions. They were also identified and characterized by GC-MS and HPLC-DAD. Then, antioxidant activity was examined by ß-carotene bleaching and DPPH radical scavenger tests. Results and Conclusion. The mother extract hexane FH generated eight different fractions (SH1-8) and the acetone extract FA generated 11 fractions (SA1-11). The FH fractions had a high percentage of fatty acids, and the FA fractions had some interesting polyphenols derivative compounds. Phytochemical screening revealed secondary metabolites such as polyphenols flavonoids, alkaloids, steroids, terpenes coumarins, tannins, and saponins. We found that only two solvents (hexane, acetone) of different polarities could easily extract and simultaneously separate the components of Nigella sativa L. The antioxidant fractions that we collected had close activity to reference compounds but were more active than the corresponding mother extracts. Moreover, several IC50 values of fractions from acetone extract were better than those from hexane. Therefore, the antioxidant activity of Nigella sativa L is more attributed to flavonoids and polyphenols than fatty acids. In summary, the separation of hexane extract presents a more pronounced positive effect for antioxidant tests than acetone extract.
Asunto(s)
Antioxidantes/aislamiento & purificación , Flavonoides/aislamiento & purificación , Extracción Líquido-Líquido/métodos , Nigella sativa/química , Fitoquímicos/aislamiento & purificación , Polifenoles/aislamiento & purificación , Semillas/química , Acetona/química , Alcaloides/química , Alcaloides/clasificación , Alcaloides/aislamiento & purificación , Antioxidantes/química , Antioxidantes/clasificación , Compuestos de Bifenilo/antagonistas & inhibidores , Cromatografía Líquida de Alta Presión , Cumarinas/química , Cumarinas/clasificación , Cumarinas/aislamiento & purificación , Flavonoides/química , Flavonoides/clasificación , Hexanos/química , Humanos , Marruecos , Fitoquímicos/química , Fitoquímicos/clasificación , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Plantas Medicinales , Polifenoles/química , Polifenoles/clasificación , Saponinas/química , Saponinas/clasificación , Saponinas/aislamiento & purificación , Solventes/química , Esteroides/química , Esteroides/clasificación , Esteroides/aislamiento & purificación , Taninos/química , Taninos/clasificación , Taninos/aislamiento & purificación , Terpenos/química , Terpenos/clasificación , Terpenos/aislamiento & purificación , beta Caroteno/agonistasRESUMEN
The aim of this paper was to investigate how maturity affects the aroma characteristics of Cabernet Sauvignon wine. A series of four Vitis vinifera cv. Cabernet Sauvignon wines were produced from grapes of different harvest dates. The berries of sequential harvest treatments showed an increase in total soluble solids and anthocyanin and a decrease in titratable acidity. Berry shriveling was observed as berry weight decreased. In the wines, anthocyanin, dry extract, alcoholic strength, and pH were enhanced with the sequential harvest, whereas polyphenol and tannin were decreased. The concentrations of volatile compounds in sequential harvests were found to be at higher levels. Isopentanol, phenylethyl alcohol, ethyl acetate, ethyl lactate, benzaldehyde, citronellol, and linalool significantly increased when harvest was delayed by one or two weeks. Through a principal component analysis, the volatile compounds and phenols characterizing each harvest date were clearly differentiated. These results suggest that sequential harvest may be an optional strategy for winemakers to produce high-quality wine.
Asunto(s)
Frutas/química , Odorantes/análisis , Vitis/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Vino/análisis , Antocianinas/biosíntesis , Antocianinas/aislamiento & purificación , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Polifenoles/biosíntesis , Polifenoles/clasificación , Polifenoles/aislamiento & purificación , Análisis de Componente Principal , Taninos/biosíntesis , Taninos/clasificación , Taninos/aislamiento & purificación , Factores de Tiempo , Vitis/crecimiento & desarrollo , Vitis/metabolismo , Compuestos Orgánicos Volátiles/clasificación , Compuestos Orgánicos Volátiles/metabolismoRESUMEN
This study investigated the phytochemical characteristics and antioxidant activity in leaves, roots, stem, flower, and seed parts of Datura alba (D. alba). The study also assessed the heavy metal (Cr, Mn, Zn, and Cu) accumulation in each part of the plant. Among the phytochemicals, alkaloids were found only in leaves while tannins, flavonoids, and phenols were present in all parts of the plant. For antioxidant activity, free radical scavenging assay for 2,2-diphenyl-1-picrylhydrazyl (DPPH) was performed using ascorbic acid as the standard. Higher activity was shown by stem extract in methanol and leaf extract in n-hexane, ethyl acetate, and chloroform. Furthermore, all the target heavy metals were detected in all plant sections with the highest concentration of Zn in leaves and Cu in stem, root, flower, and seed. Due to stronger antioxidant potential and phytochemical composition, D. alba could prove as valuable prospect in pharmaceutical formulations by taking part in the antioxidant defense system against generation of free radicals.
Asunto(s)
Antioxidantes/química , Datura/química , Radicales Libres/antagonistas & inhibidores , Metales Pesados/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Alcaloides/química , Alcaloides/aislamiento & purificación , Antioxidantes/farmacología , Flavonoides/química , Flavonoides/aislamiento & purificación , Metales Pesados/química , Metales Pesados/clasificación , Fenoles/química , Fenoles/aislamiento & purificación , Fitoquímicos/química , Fitoquímicos/clasificación , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Semillas/química , Taninos/química , Taninos/clasificación , Taninos/aislamiento & purificaciónRESUMEN
Attenuated total reflection Fourier transform infrared (FT-IR) spectroscopy was used to characterize 40 commercial tannins, including condensed and hydrolyzable chemical classes, provided as powder extracts from suppliers. Spectral data were processed to detect typical molecular vibrations of tannins bearing different chemical groups and of varying botanical origin (univariate qualitative analysis). The mid-infrared region between 4000 and 520 cm(-1) was analyzed, with a particular emphasis on the vibrational modes in the fingerprint region (1800-520 cm(-1)), which provide detailed information about skeletal structures and specific substituents. The region 1800-1500 cm(-1) contained signals due to hydrolyzable structures, while bands due to condensed tannins appeared at 1300-900 cm(-1) and exhibited specific hydroxylation patterns useful to elucidate the structure of the flavonoid monomeric units. The spectra were investigated further using principal component analysis for discriminative purposes, to enhance the ability of infrared spectroscopy in the classification and quality control of commercial dried extracts and to enhance their industrial exploitation.
Asunto(s)
Espectroscopía Infrarroja por Transformada de Fourier/métodos , Taninos/análisis , Taninos/química , Algoritmos , Análisis de Componente Principal , Taninos/clasificaciónRESUMEN
ABSTRACTSome ichthyotoxic plants are study object aiming to discover promising substances in the field of Biotechnology, in search of plant extracts which can be used or even transformed into natural insecticides. This paper presents a bibliographical survey in order to check the traditional use of ichthyotoxic plants as bioinsecticide. Among the plants identified as ichthyotoxic, the most cited in traditional use are those from the genera Derris, Serjania, Lonchocarpus, Magonia, and Tephrosia. The survey suggests that ichthyotoxic plant extracts can contain classes of chemical compounds such as isoflavonoids and tannins with a bioinsecticidal effect and, thus, they can be used in Biotechnology, contributing to reduce the use of synthetic insecticides that present a high toxicity level.
RESUMOUso de plantas ictiotóxicas como bioinseticida: revisão de literatura. Algumas plantas ictiotóxicas são objeto de estudos com a finalidade de descobrir substâncias promissoras no campo da Biotecnologia, na busca de extratos vegetais que possam ser usados ou mesmo transformados em inseticidas naturais. Esse artigo apresenta uma pesquisa bibliográfica sobre o uso tradicional de plantas ictiotóxicas como bioinseticida. Entre as plantas identificadas como ictiotóxicas, as mais citadas no uso tradicional são as dos gêneros Derris, Serjania, Lonchocarpus, Magonia e Tephrosia. A pesquisa sugere que extratos de plantas ictiotóxicas podem conter classes de compostos químicos, como isoflavonoides e taninos, com efeito bioinseticida e, assim, podem ser usados na Biotecnologia, contribuindo na redução do uso de inseticidas sintéticos que possuem alto nível de toxicidade.
Asunto(s)
Biotecnología/instrumentación , Extractos Vegetales/farmacología , Taninos/clasificación , InsecticidasRESUMEN
Wine tannins are fundamental to the determination of wine quality. However, the chemical and sensorial analysis of these compounds is not straightforward and a simple and rapid technique is necessary. We analyzed the mid-infrared spectra of white, red, and model wines spiked with known amounts of skin or seed tannins, collected using Fourier transform mid-infrared (FT-MIR) transmission spectroscopy (400-4000 cm(-1)). The spectral data were classified according to their tannin source, skin or seed, and tannin concentration by means of discriminant analysis (DA) and soft independent modeling of class analogy (SIMCA) to obtain a probabilistic classification. Wines were also classified sensorially by a trained panel and compared with FT-MIR. SIMCA models gave the most accurate classification (over 97%) and prediction (over 60%) among the wine samples. The prediction was increased (over 73%) using the leave-one-out cross-validation technique. Sensory classification of the wines was less accurate than that obtained with FT-MIR and SIMCA. Overall, these results show the potential of FT-MIR spectroscopy, in combination with adequate statistical tools, to discriminate wines with different tannin levels.
Asunto(s)
Biología Computacional , Umbral Sensorial , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Taninos/análisis , Vino/análisis , Vino/clasificación , Análisis Discriminante , Odorantes , Taninos/clasificación , Gusto , Vitis/químicaRESUMEN
Nowadays, many researches have been made on gallotannin biodegradation and have gained great success in further utilization. Some of industrial applications of these findings are in the production of tannase, the biotransformation of tannic acid to gallic acid or pyrogallol and detannification of food and fodder. Although ellagitannins have the typical C-C bound which is more difficult to be degraded than gallotannins, concerted efforts are still in progress to improve ellagitannin degradation and utilization. Currently, more attention is mainly focused on intestinal microflora biodegradation of tannins especially ellagitannins which can contribute to the definition of their bioavailability for both human beings and ruminants. Also there have been endeavours to utilize the tannin-degrading activity of different fungi for ellagitannin-rich biomass, which will facilitate application of tannin-degrading enzymes in strategies for improving industrial and livestock production. Due to the complicated structures of complex tannins and condensed tannins, the biodegradation of them is much more difficult and there are fewer researches on them. Therefore, the researches on the mechanisms of gallotannin and ellagitannin biodegradation can result in the overall understanding to the biodegradation of complex tannins and condensed tannins. Biodegradation of tannins is in an incipient stage and further studies have to be carried out to exploit the potential of various tannins for largescale applications in food, fodder, medicine and tannery effluent treatment.
Asunto(s)
Taninos Hidrolizables/metabolismo , Animales , Bacterias/enzimología , Bacterias/metabolismo , Biodegradación Ambiental , Hidrolasas de Éster Carboxílico/metabolismo , Alimentos , Industria de Alimentos , Hongos/enzimología , Hongos/metabolismo , Ácido Gálico/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Taninos/química , Taninos/clasificación , Taninos/metabolismoRESUMEN
We examined the antibacterial action of several tannins on plasma coagulation by Staphylococcus aureus and the effect of conventional chemotherapy combined with tannic acid below the MIC. Coagulation was inhibited in plasma containing tannic acid (100 mg/L), gallic acid (5000 mg/L), ellagic acid (5000 mg/L), (-)-epicatechin (1500 mg/L), (-)-epicatechin gallate (500 mg/L) or (-)-epigallocatechin gallate (200 mg/L) after incubation for 24 h. All tannins inhibited coagulation at a concentration below the MIC. The MICs of oxacillin and cefdinir for S. aureus were reduced to < or = 0.06 mg/L in Mueller-Hinton agar plates with tannic acid (100 mg/L) at a concentration below the MIC. The antistaphylococcal activity of tannic acid was reduced in plates with 10% rabbit blood, but not in those with 10% rabbit plasma. Membranous structures formed in a culture medium containing equal proportions of plasma and tryptic soy broth after incubation for 24 h. The colony counts of S. aureus in membranous structures in the medium containing oxacillin (40 mg/L) and tannic acid (100 mg/L) were c. 10-fold lower than those in medium containing oxacillin (40 mg/L) alone (P < 0.01). Tannic acid merits further investigation as a possible adjuvant agent against S. aureus skin infections treated with beta-lactam antibiotics.
Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Taninos/farmacología , Antibacterianos/farmacología , Cefdinir , Cefalosporinas/farmacología , Recuento de Colonia Microbiana , Medios de Cultivo , Quimioterapia Combinada , Humanos , Taninos Hidrolizables/farmacología , Pruebas de Sensibilidad Microbiana , Oxacilina/farmacología , Infecciones Estafilocócicas/microbiología , Taninos/clasificaciónRESUMEN
Structure and function of polypehnols with high molecular weights (tannins) were briefly reviewed to better understand the significance of polyphenol-rich foods and beverages. In a survey of bioactive ellagiannins with a macrocyclic structure and/or a gluconic acid core, some new oligomeric ellagitannins (eucarpanins and elaeagnatins) have been found in species of Myrtaceae and Elaeagnaceae, and their structures were elucidated by spectroscopic and chemical methods. Cytotoxic activity against human oral tumor cell lines and antibacterial activity against Helicobacter pylori have been evaluated for the ellagitannins obtained from both plants, and related compounds. The macrocyclic dimers, oentothein B, camelliin B and woodfordin C showed a remarkable cytotoxicity against human oral squamous cell carcinoma, but not against normal cells. These active tannins induced apoptosis of tumor cells. A potent antibacterial activity against Helicobacter pylori was exhibited by monomeric ellagitannins such as tellimagrandin I and stricitinin.
Asunto(s)
Anticarcinógenos/química , Anticarcinógenos/farmacología , Flavonoides , Fenoles/química , Fenoles/farmacología , Polímeros/química , Polímeros/farmacología , Verduras , Antibacterianos/química , Antibacterianos/farmacología , Supervivencia Celular/efectos de los fármacos , Helicobacter pylori/efectos de los fármacos , Humanos , Estructura Molecular , Peso Molecular , Neoplasias de la Boca , Polifenoles , Taninos/química , Taninos/clasificación , Taninos/farmacología , Células Tumorales CultivadasRESUMEN
Tannins (commonly referred to as tannic acid) are water-soluble polyphenols that are present in many plant foods. They have been reported to be responsible for decreases in feed intake, growth rate, feed efficiency, net metabolizable energy, and protein digestibility in experimental animals. Therefore, foods rich in tannins are considered to be of low nutritional value. However, recent findings indicate that the major effect of tannins was not due to their inhibition on food consumption or digestion but rather the decreased efficiency in converting the absorbed nutrients to new body substances. Incidences of certain cancers, such as esophageal cancer, have been reported to be related to consumption of tannins-rich foods such as betel nuts and herbal teas, suggesting that tannins might be carcinogenic. However, other reports indicated that the carcinogenic activity of tannins might be related to components associated with tannins rather than tannins themselves. Interestingly, many reports indicated negative association between tea consumption and incidences of cancers. Tea polyphenols and many tannin components were suggested to be anticarcinogenic. Many tannin molecules have also been shown to reduce the mutagenic activity of a number of mutagens. Many carcinogens and/or mutagens produce oxygen-free radicals for interaction with cellular macromolecules. The anticarcinogenic and antimutagenic potentials of tannins may be related to their antioxidative property, which is important in protecting cellular oxidative damage, including lipid peroxidation. The generation of superoxide radicals was reported to be inhibited by tannins and related compounds. The antimicrobial activities of tannins are well documented. The growth of many fungi, yeasts, bacteria, and viruses was inhibited by tannins. We have also found that tannic acid and propyl gallate, but not gallic acid, were inhibitory to foodborne bacteria, aquatic bacteria, and off-flavor-producing microorganisms. Their antimicrobial properties seemed to be associated with the hydrolysis of ester linkage between gallic acid and polyols hydrolyzed after ripening of many edible fruits. Tannins in these fruits thus serve as a natural defense mechanism against microbial infections. The antimicrobial property of tannic acid can also be used in food processing to increase the shelf-life of certain foods, such as catfish fillets. Tannins have also been reported to exert other physiological effects, such as to accelerate blood clotting, reduce blood pressure, decrease the serum lipid level, produce liver necrosis, and modulate immunoresponses. The dosage and kind of tannins are critical to these effects. The aim of this review is to summarize and analyze the vast and sometimes conflicting literature on tannins and to provide as accurately as possible the needed information for assessment of the overall effects of tannins on human health.