Propolis from Southwest of Parana produced by selected bees: Influence of seasonality and food supplementation on antioxidant activity and phenolic profile

ABSTRACT Propolis produced by selected bees Apis mellifera were collected from March to June of 2013 and in March of 2015 and analyzed in order to evaluate the influence of climate, colony of origin, and food supplementation of colonies on the content of total phenolic and flavonoid by chromatographic analysis and antioxidant activity by radical scavenging of 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods. The Principal Component Analysis (PCA) was carried out with propolis collected in 2013 and two clusters were formed. Propolis produced in the months of March and April showed a higher content of total phenolic compounds (TPC) and antioxidant capacity than those produced in May and June. The results of PCA obtained from samples collected in March of 2013 and 2015 showed two clusters, and propolis collected in 2015 were more bioactive and presented a higher content of TPC. The chromatographic analysis of extracts allowed the identification of phenolic acids p-coumaric, ferulic and caffeic with similar chemical profiles that could be closely related to the botanical origin of propolis. It can be concluded that the season and food supplementation of colonies influenced the chemical composition and the biological activity of samples analysed.

Dinámica de polifenoles en ephedra tweediana fisch & C. A. Mey. emend. J. H. Hunz. (Ephedraceae) / Polyphenol dinamics in ephedra tweediana fisch & C. A. Mey. emend. J. H. Hunz. (Ephedraceae)

Ephedra tweediana (Ephedraceae), conocida como “tramontana”, es empleada en la medicina popular como antiasmático. Se analizaron comparativamente los extractos acuosos de los tallos herbáceos, lignificados y partes subterráneas, provenientes de ejemplares femeninos y masculinos. En los tallos lignificados se determinó la presencia de proapigeninidina (cuya identidad fue corroborada por comparación con un testigo de apigeninidina sometido a estudios de FAB-MS, UV, HPLC, 1H-NMR y espectroscopía IR); mientras que en los órganos subterráneos se determinó la presencia de proapigeninidina y propelargonidina (la identidad de la pelargonidina fue establecida por comparación con un testigo de pelargonidina sometido a estudios de TLC/HPTLC y espectroscopía UV-Visible). Estos compuestos no se observaron en los tallos herbáceos. Los tallos herbáceos presentaron las mayores concentraciones de flavonoides y ácidos hidroxicinámicos totales. Los órganos subterráneos presentaron la mayor concentración de taninos y proantocianidinas. En los tallos herbáceos se detectó una reacción fuertemente positiva para flavonoides. No se observó reacción positiva para proantocianidinas. En el tallo aéreo lignificado se observó una reacción positiva para flavonoides y proantocianidinas a nivel de la peridermis. En los órganos subterráneos, los flavonoides y proantocianidinas se localizaron principalmente en los tejidos más externos. Este trabajo constituye el primer aporte a la dinámica de polifenoles de E. tweediana.

Ephedra tweediana (Ephedraceae), known as "tramontana" is used in folk medicine as antiasthmatic. Aqueous extracts obtained from young stems, woody stems and underground parts were analyzed and compared. In lignified stems was detected proapigeninidin (whose identity was confirmed by comparison with a control apigeninidin subjected to FAB-MS, UV, HPLC, 1H-NMR and IR spectroscopy), while underground organs were detected proapigeninidin and propelargonidin (by comparison with a control pelargonidin whose identity was established by studies of TLC/HPTLC, and UV-visible spectroscopy). These compounds were not observed in the herbaceous stems. The herbaceous stems had the highest concentrations of total flavonoids and hydroxycinnamic acids. Uderground organs had the highest concentration of tannins and proanthocyanidins. In herbaceous stems a strong positive reaction for flavonoids was detected. No positive reaction was observed for proanthocyanidins. In the periderm of woody aerial stem a positive reaction for flavonoids and proanthocyanidins were observed. In the underground organs, flavonoids and proanthocyanidins were located mainly in the more external tissues. This work is the first contribution to the dynamic of E. tweediana polyphenols.

Sugars, organic acids, and phenolic compounds of ancient grape cultivars (Vitis vinifera L.) from Igdir province of Eastern Turkey

BACKGROUND: The Eurasian grapevine (Vitis vinifera L.) is the most widely cultivated and economically important horticultural crop in the world. As a one of the origin area, Anatolia played an important role in the diversification and spread of the cultivated form V. vinifera ssp. vinifera cultivars and also the wild form V. vinifera ssp. sylvestris ecotypes. Although several biodiversity studies have been conducted with local cultivars in different regions of Anatolia, no information has been reported so far on the biochemical (organic acids, sugars, phenolic acids, vitamin C) and antioxidant diversity of local historical table V. vinifera cultivars grown in Igdir province. In this work, we studied these traits in nine local table grape cultivars viz. 'Beyaz Kismis' (synonym name of Sultanina or Thompson seedless), 'Askeri', 'El Hakki', 'Kirmizi Kismis', 'Inek Emcegi', 'Hacabas', 'Kerim Gandi', 'Yazen Dayi', and 'Miskali' spread in the Igdir province of Eastern part of Turkey. RESULTS: Variability of all studied parameters is strongly influenced by cultivars (P < 0.01). Among the cultivars investigated, 'Miskali' showed the highest citric acid content (0.959 g/l) while 'Kirmizi Kismis' produced predominant contents in tartaric acid (12.71 g/l). The highest glucose (16.47 g/100 g) and fructose (15.55 g/100 g) contents were provided with 'Beyaz Kismis'. 'Kirmizi Kismis' cultivar had also the highest quercetin (0.55 mg/l), o-coumaric acid (1.90 mg/l), and caffeic acid (2.73 mg/l) content. The highest ferulic acid (0.94 mg/l), and syringic acid (2.00 mg/l) contents were observed with 'Beyaz Kismis' cultivar. The highest antioxidant capacity was obtained as 9.09 μmol TE g-1 from 'Inek Emcegi' in TEAC (Trolox equivalent Antioxidant Capacity) assay. 'Hacabas' cultivar had the highest vitamin C content of 35.74 mg/100 g. CONCLUSIONS: Present results illustrated that the historical table grape cultivars grown in Igdir province of Eastern part of Turkey contained diverse and valuable sugars, organic acids, phenolic acids, Vitamin C values and demonstrated important antioxidant capacity for human health benefits. Further preservation and use of this gene pool will be helpful to avoid genetic erosion and to promote continued agriculture in the region.

Induction of secondary metabolite production by UV-C radiation in Vitis vinifera L. Öküzgözü callus cultures

BACKGROUND: The aim of the present work was to examine the role of UV-C irradiation on the production of secondary metabolites (total phenolic, total flavanols, total flavonols, catechin, ferulic acid and trans-resveratrol in phenolic compounds and α-, ß-, γ- δ-tocopherols) in callus cultures. Studies on the effects of UV-C treatment on callus culture are seldom and generally focused on UV-B. However UV-C radiation play an important role in accumule secondary metabolites. RESULTS: In this study, callus cultures from Öküzgözü grape cultivar were initiated from leaf petiole explants. Calli formed after 6 weeks on the medium supplemented with 0.5 mg L-1 benzylaminopurine (BA), 0.5 mg L-1 indole acetic acid (IAA) on B5 media. Callus tissues were exposed to UV-C irradiation at 10, 20 and 30 cm distances from the UV source for 5 and 10 minutes and samples were collected at hours 0, 24 and 48. CONCLUSIONS: The greatest total phenolic content (155.14 mg 100 g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. 24 h and 48 h incubation times, 30 cm and 5 min were the most appropriate combination of UV-C application in total flavanol content. Maximum total flavonol content (7.12 mg 100 g-1) was obtained on 0 h, 5 min and 20 cm combination. The highest (+)- catechin accumulation (8.89 mg g-1) was found in calli with 10 min UV-C application from 30 cm distance and sampled after 48 h. Ferulic acid content increased 6 fold in Öküzgözü callus cultures (31.37 µg g-1) compared to the control group. The greatest trans-resveratrol content (8.43 µg g-1) was detected in calli exposed to UV-C for 5 min from 30 cm distance and sampled after 24 h. The highest α-tocopherol concentration was found in calli exposed to UV-C for 10 min from 30 cm distance and sampled after 24 h. As a conclusion, it was showed that UV-C radiation had remarkable promoting effects on the accumulation of secondary metabolites in the calli of Öküzgözü grape cultivar.

Effect of chlorocholine chlorid on phenolic acids accumulation and polyphenols formation of buckwheat plants

BACKGROUND: Effect of chlorocholine chloride (CCC) on phenolic acids composition and polyphenols accumulation in various anatomical parts (stems, leaves and inflorescences) of common buckwheat (Fagopyrum esculentum Moench) in the early stages of vegetation period were surveyed. RESULTS: Treatment of buckwheat seeds with 2% of CCC has been increased content of total phenolics in the stems, leaves and inflorescences. On analyzing the different parts of buckwheat plants, 9 different phenolic acids - vanilic acid, ferulic acid, trans-ferulic acid, chlorogenic acid, salycilic acid, cinamic acid, p-coumaric acid, p-anisic acid, methoxycinamic acid and catechins were identified. The levels of identified phenolic acids varied not only significantly among the plant organs but also between early stages of vegetation period. Same changes as in contents of chlorogenic acid, ferulic acid, trans-ferulic acid were found for content of salycilic acid. The content of these phenolic acids has been significant increased under effect of 2% CCC treatment at the phase I (formation of buds) in the stems and at the phase II (beginning of flowering) in the leaves and then inflorescences respectively. The content of catechins as potential buckwheat antioxidants has been increased at the early stages of vegetation period after treatment with 2% CCC. CONCLUSIONS: The obtained results suggest that influence of CCC on the phenolics composition can be a result of various mechanisms of CCC uptake, transforming and/or its translocation in the buckwheat seedlings.

Validação de metodologia analítica para a determinação de derivados do ácido o-hidroxicinâmico de Echinodorus grandiflorus / Validation of analytical methodology for the determination of derivatives of o-hydroxycinnamic acid from Echinodorus grandiflorus

Este artigo descreve o desenvolvimento e a validação de método espectrofotométrico UV-Visível para quantificação de derivados do ácido o-hidroxicinâmico em folhas de Echinodorus grandiflorus. O método demonstrou ser linear (r² = 0,9974), preciso (DPR < 15%) na análise de matriz complexa e exata (recuperação = 107,56%).

This paper describes the development and the validation of an UV-Vis spectrophotometric method for the quantification of derivatives of o-hydroxycinnamic acid in leaves of Echinodorus grandiflorus. The method showed to be linear (r² = 0.9974), precise (RSD < 15%) in the analysis of complex matrix and accurate (recovery = 107.56%).

Polifenoles y actividad antioxidante en Equisetum giganteum L. (Equisetaceae) / Polyphenols and antioxidant activity in Equisetum giganteum L. (Equisetaceae)

Equisetum giganteum L. (Equisetaceae) is a species native to South America and Central America, which is used in traditional medicine as a diuretic and in treating of various diseases. The aim of this paper was to study the polyphenol profile and antioxidant activity of extracts obtained from lateral branches and main stem of the plants. Quali- and quantitative differences were detected with higher contents of phenols, tannins, condensed tannins, flavonoids and hydroxicinnamic acids in the lateral branches. The proanthocyanidins propelargonidin and procyanidin only were detected in lateral branches. These extracts showed the highest antioxidant activity. Due to their higher concentration and chemical composition, lateral branches could be considered as a sort of source of compounds that would act as antioxidant.

Equisetum giganteum L. (Equisetaceae) es una especie nativa de Sudamérica y América Central, que es empleada en la medicina tradicional como diurético y en el tratamiento de diversas patologías. El objetivo de este trabajo fue estudiar el perfil de polifenoles y la actividad antioxidante de extractos obtenidos de las ramas laterales (tallos finos), tallos entrenudos y tallos basales. Se detectaron diferencias cuali-cuantitativas, con mayor contenido de fenoles, taninos, taninos condensados, flavonoides y ácidos hidroxicinámicos en las ramas laterales. Las proantocianidinas propelargonidina y procianidina sólo se detectaron en las ramas laterales. En estos extractos se detectó la mayor actividad antioxidante. Debido a la alta concentración y composición química, los tallos laterales podrían ser empleados como fuente de compuestos con actividad antioxidante.

Dinámica de polifenoles de “Cedrón” (Aloysia citrodora Palau -Verbenaceae-) en relación al desarrollo foliar / Polyphenol dinamics on “cedrón” (Aloysia citrodora Palau -Verbenaceae-) according to leave development

Leaf infusions from Aloysia citrodora Palau –Verbenaceae-, known as “cedrón” were analyzed in order to establish the possible influence of their development on polyphenols profile. Chromatographic fingerprints of infusions from young and full expanded leaves were performed and total phenols, total tannins, total flavonoids and total hydroxycinnamic acids were quantified. Young leaves had significative higher total phenols, total flavonoids and total hydroxycinnamic acids concentrations than full expanded leaves. This research suggest that the analyzed parameter should be considered when elaborating products from “cedrón” leaves, as the variation in compound concentration may translate in different biological activities.

Se analizaron las infusiones realizadas a partir de las hojas de Aloysia citrodora Palau –Verbenaceae-, conocida vulgarmente como “cedrón”, con el objeto de establecer la influencia del grado de desarrollo foliar en el perfil de polifenoles. Se obtuvieron los perfiles cromatográficos y se cuantificaron los fenoles totales, taninos totales, flavonoides totales y ácidos hidroxicinámicos totales provenientes de los extractos acuosos de las hojas jóvenes y adultas. Se observaron diferencias cuali-cuantitativas en el perfil de polifenoles cuando se comparan las hojas jóvenes con las hojas adultas. En las hojas jóvenes, las concentraciones de fenoles totales, flavonoides totales y ácidos hidroxicinámicos totales resultaron ser significativamente superiores a las determinadas en las hojas adultas. Los estudios realizados sugieren que la variable aquí analizada debe ser considerada al momento de elaborar productos en base a hojas de cedrón, dado que las diferentes concentraciones detectadas podrían traducirse en diferentes actividades biológicas.

Análisis de polifenoles, actividad antioxidante y genotoxicidad en especies argentinas de Lippia y Aloysia (Verbenaceae) / Survey on polyphenols, antioxidant activity and genotoxicity on Argentinean species of Lippia and Aloysia (Verbenaceae)

Three species and a variety from the Verbenaceae belonging to the argentinean flora were analyzed: Aloysia gratissima var. gratissima (Gill. Et Hook) Tronc., Aloysia gratissima var. schulziana (Moldenke) Botta, Aloysia polystachya (Griseb.) Moldenke and Lippia integrifolia (Griseb.) Hieron., the first two known as “cedrón del monte”, the third as “yerba del burro” and the other as “incayuyo”. Their leaves are used as digestive in folk medicine. The research was performed on quantification of polyphenols (total phenols, total flavonoids and total hydroxicinnamic acids) and on determination of antioxidant and genotoxic activities. L. integrifolia showed the highest total phenol concentration and A. polystachya the lowest, but with the highest concentration of hydroxicinnamic acids. When flavonoids were quantified, A. polystachya showed the lowest concentations and A. gratissima var. schultziana the highest. According to quantification of total polyphenols, the lowest antioxidant activity was measured in A. polystachya extracts, followed by those from A. gratissima var. gratissima and A. gratissima var. schulziana, while extracts from L. integrifolia showed the highest antioxidant activity. No genotoxic activity was detected by means of the comet-assay for any of the species. This absence of genotoxicity, added to the relevant antioxidant activity, could justify the use of leaves infusions and decoctions from these species in treatments of those pathologies where antioxidants play an important role. These studies suggest their sure use in folk medicine, in which people include them among their medicinal plants.

Se analizaron 3 especies y una variedad de la familia Verbenaceae de la flora argentina: Aloysia gratissima var. gratissima (Gill. Et Hook) Tronc., Aloysia gratissima var. schulziana (Moldenke) Botta, Aloysia polystachya (Griseb.) Moldenke y Lippia integrifolia (Griseb.) Hieron., conocidas como “cedrón del monte” las dos primeras, “yerba del burro” la tercera e “incayuyo” la restante. De todas ellas se emplean las hojas en la medicina popular como digestivas. Se investigaron los contenidos de polifenoles (fenoles totales, flavonoides totales y ácidos hidroxicinámicos totales) y se determinó la capacidad antioxidante y genotoxicidad de las preparaciones acuosas (infusiones y cocimientos). L. integrifolia fue la especie con mayor contenido de fenoles totales y A. polystachya la menor. En el análisis de los hidroxicinámicos, A. polystachya fue la que mayor concentración mostró. En cuanto a los flavonoides, A. polystachya fue la que poseyó menor concentración en tanto que A. gratissima var. schultziana fue la más rica en estos compuestos. A. polystachya es la especie que presenta los menores valores de actividad antioxidante, seguida por A. gratissima var. gratissima y A. gratissima var. schulziana, mientras que L. integrifolia es la especie con mayor actividad antioxidante, en correlación con los valores de polifenoles totales. Ninguna de las especies analizadas demostró actividad genotóxica en el ensayo del cometa. La ausencia de genotoxicidad, sumada a una marcada actividad antioxidante, justificarían el empleo de las infusiones y cocimientos en el tratamiento de aquellas patologías donde los agentes antioxidantes juegan un importante rol terapéutico. Estos estudios sugieren el empleo seguro en la medicina tradicional de los pueblos y comunidades que las incluyen entre sus plantas medicinales.