EQUASS kvaliteedijuhtimissüsteemi juurutamisprotsess MTÜ Noore Vanema Perekeskuse näitel

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Identification and characterization of phenolic compounds in hydromethanolic extracts of sorghum wholegrains by LC-ESI-MSn

Hydromethanolic extracts of brown, red, and white sorghum whole grains were analysed by LC-MSn in negative ESI mode within the range m/z 150–550 amu. Besides the flavonoids already reported in sorghum, a number of flavonoids were also identified in the sorghum grain for the first time, including flavanones, flavonols and flavanonols, and flavan-3-ol derivatives. Various phenylpropane glycerides were also found in the sorghum grain, the majority of them are reported here for the first time, and a few of them were detected with abundant peaks in the extracts, indicating they are another important class of phenolic compounds in sorghum. In addition, phenolamides were also found in sorghum grain, which have not been reported before, and dicaffeoyl spermidine was detected in high abundance in the extracts of all three type sorghum grains. These results confirmed that sorghum is a rich source of various phenolic compounds

Kemijski sastav te antioksidacijski, citotoksični i insekticidni potencijal valerijane Valeriana alliariifolia u Turskoj

Valeriana is a common plant species used for various healing purposes in folk medicine since antiquity. This study investigates the phytochemical profile, antioxidant, cytotoxic, and insecticidal activity of Valeriana alliariifolia Adams, a species that has traditionally been used in Turkey. For the analyses we prepared four root extracts of V. alliariifolia Adams using hexane (HM1), chloroform (CM1), ethanol (EM1), and water (WM1) for maceration. Additionally, two extracts were also prepared from its roots by maceration separately with ethanol (EM2) and water (WM2). One sample was prepared as a water infusion (WI), according to the procedure used in Turkish traditional medicine. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation scavenging activity tests showed that ethanol extracts had the strongest antioxidant activity: EM1 (IC50 – DPPH: 17.694 μg/mL; ABTS: 23.8 μg/mL) and EM2 (IC50 – DPPH: 20 μg/mL; ABTS: 21.5 μg/mL). The hexane extract, HM1, was the most cytotoxic (IC50<10 μg/mL against HepG2 and HUVEC) and EM2 strongly cytotoxic (IC50<10 μg/mL against HepG2 and IC50: 11.96 μg/mL against HUVEC). The extracts with demonstrated cytotoxic activities were further examined to check their insecticidal activity against adult female mosquito Aedes aegypti and first instar Ae. aegypti larvae. HM1 was the most effective (90±10 %), which was consistent with its cytotoxic activity. Because of the high antioxidant, cytotoxic, and insecticidal activities, we ran phytochemical analyses of the HM1, EM1, and EM2 extracts with GC-MS (for HM1) and LC-MS/MS (for EM1 and EM2). We also analysed the composition of the essential oil obtained from V. alliariifolia roots by micro-distillation in order to compare its content with HM1, which contains volatile compounds. Phytochemical analyses revealed that the major compound in HM1 was isovaleric acid (16 %) and in the essential oil 1,8-cineole (2.9 %). EM1 and EM2 contained 5-O-caffeoylquinic acid (chlorogenic acid), verbascoside (acteoside), and 3,5-dicaffeoylquinic acid as major components. In the light of our findings and available literature, we can conclude that V. alliariifolia has a good bioactive potential that could be used for different purposes, including the development of new agents for the treatment of various diseases. The difference in the content between the essential oil and HM1 was remarkable. It suggests that the variability observed in the activity of the samples was a result of composition and that, therefore, the aim of treatment should dictate which type of preparation is to be selected. An added value of our study is that it determined verbascoside and methylquercetin rutinoside for the first time in the Valeriana extracts.Valerijana (odoljen) česta je biljna vrsta koja se zbog svojih ljekovitih svojstava od davnina rabi u narodnoj medicini. U ovome se istraživanju utvrdio fitokemijski profil te antioksidacijsko, citotoksično i insekticidno djelovanje tradicionalne vrste koja se za liječenje rabi u Turskoj – Valeriana alliariifolia Adams. Za analizu je maceracijom pripremljeno šest ekstrakata njezina korijena pomoću heksana (HM1), kloroforma (CM1), etanola (EM1, EM2) i vode (WM1, WM2). Jedan je uzorak pripremljen infuzijom vodom (WI) prema tradicionalnom turskom receptu za ljekovite pripravke. Testovima antioksidacijskoga djelovanja pomoću 2,2-difenil-1-pikrilhidrazila (DPPH) i 2,2’-azino-bis(3-etilbenzotiazolin-6-sulfonične kiseline (ABTS) izdvojeni su sljedeći ekstrakti s najjačim antioksidacijskim djelovanjem: EM1 (IC50 – DPPH: 17,694 μg/mL; ABTS: 23,8 μg/mL) i EM2 (IC50 – DPPH: 20 μg/mL; ABTS: 21,5 μg/mL). Ekstrakt s heksanom, HM1, iskazao je najveću citotoksičnost (IC50<10 μg/mL protiv tumorskih stanica HepG2 i HUVEC), a EM2 snažnu citotoksičnost (IC50<10 μg/mL protiv HepG2 stanica te IC50 11,96 μg/mL protiv HUVEC stanica). Ekstrakte s najsnažnijim citotoksičnim djelovanjem također smo analizirali za insekticidno djelovanje protiv odraslih ženki komarca vrste Aedes aegypti te njihovih ličinki. U skladu sa svojom citotoksičnosti, HM1 se pokazao najdjelotvornijim (smrtnost 90±10 %). Zbog snažnog antioksidacijskog, citotoksičnog i insekticidnog djelovanja, napravili smo i fitokemijsku analizu ekstrakata HM1, EM1 i EM2 služeći se metodama GC-MS (za HM1) i LC-MS/MS (za EM1 i EM2). Također smo analizirali sastav esencijalnoga ulja dobivenoga mikrodestilacijom korijena V. alliariifolia kako bismo ga usporedili sa sastavom HM1, koji je sadržavao hlapljive sastojke. Fitokemijska je analiza pokazala da je glavni sastojak HM1 izovalerijanska kiselina (16 %), a esencijalnoga ulja 1,8-cineol (2,9 %). Glavni sastojci ekstrakata EM1 i EM2 bili su 5-O-kafeoilkvinska kiselina (klorogena kiselina), verbakozid (akteozid) i 3,5-dikafeoilkvinska kiselina. U svjetlu ovih rezultata i dostupne literature, možemo zaključiti da V. alliariifolia ima dobar bioaktivni potencijal, koji se može iskoristiti za različite svrhe poput razvoja novih tvari za liječenje bolesti. Razlika u sadržaju između esencijalnoga ulja i ekstrakta HM1 pokazala se golemom te upućuje na to da su razlike u aktivnosti između uzoraka rezultat sastava, zbog čega primjena/liječenje trebaju uvjetovati koja će se vrsta pripravka odabrati. Dodatna je vrijednost ovoga istraživanja što su se u ekstraktima valerijane prvi put otkrili verbaskozid i metilkvercetin rutinozid

Hypericum sp.: essential oil composition and biological activities

Phytochemical composition of Hypericum genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization as well as biological activities of H. perforatum crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett in Nat Prod Commun 5(9):1493–1506, 2010; Bertoli et al. in Global Sci Books 5:29–47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus.Fundação para a Ciência e a Tecnologia (FCT) - project PTDC/AGR AAM/70418/2006, SFRH/BD/ 13283/2003

Reducing capacity, chlorogenic acid content and biological activity in a collection of scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants

Scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants are important vegetables in Sub-Saharan Africa. Few studies have been made on these crops regarding the diversity of phenolic content and their biological activity. We have studied the reducing activity, the chlorogenic acid and other phenolic acid contents in a collection of 56 accessions of scarlet eggplant, including the four cultivated groups (Aculeatum, Gilo, Kumba, Shum) and the weedy intermediate S. aethiopicum-S. anguivi types, as well as in eight accessions of gboma eggplant, including the cultivated S. macrocarpon and its wild ancestor, S. dasyphyllum. A sample of the accessions evaluated in this collection has been tested for inhibition of nitric oxide (NO) using macrophage cell cultures. The results show that there is a great diversity in both crops for reducing activity, chlorogenic acid content and chlorogenic acid peak area (% of total phenolic acids). Heritability (H-2) for these traits was intermediate to high in both crops. In all samples, chlorogenic acid was the major phenolic acid and accounted for more than 50% of the chromatogram peak area. Considerable differences were found among and within groups for these traits, but the greatest values for total phenolics and chlorogenic acid content were found in S. dasyphyllum. In most groups, reducing activity was positively correlated (with values of up to 0.904 in the Aculeatum group) with chlorogenic acid content. Inhibition of NO was greatest in samples having a high chlorogenic acid content. The results show that both crops are a relevant source of chlorogenic acid and other phenolic acids. The high diversity found also indicates that there are good prospects for breeding new scarlet and gboma eggplant cultivars with improved content in phenolics and bioactive properties.This research has been partially funded by Ministerio de Economia y Competitividad and FEDER (Grant AGL2012-34213) and by Conselleria d'Educacio i Esport de la Generalitat Valenciana (Grant ACOMP/2014/191). Pietro Gramazio is grateful to Universitat Politecnica de Valencia for a predoctoral fellowship.Plazas Ávila, MDLO.; Prohens Tomás, J.; Cuñat, A.; Vilanova Navarro, S.; Gramazio, P.; Herraiz García, FJ.; Andújar Pérez, I. (2014). Reducing capacity, chlorogenic acid content and biological activity in a collection of scarlet (Solanum aethiopicum) and gboma (S. macrocarpon) eggplants. International Journal of Molecular Sciences. 15(10):17221-17241. https://doi.org/10.3390/ijms151017221S17221172411510PLAZAS, M., ANDÚJAR, I., VILANOVA, S., HURTADO, M., GRAMAZIO, P., HERRAIZ, F. J., & PROHENS, J. (2013). 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Chlorogenic Acid Improves Neuroprotective Effect of PEP-1-Ribosomal Protein S3 Against Ischemic Insult. Experimental Neurobiology, 20(4), 169. doi:10.5607/en.2011.20.4.169Burgos-Morón, E., Calderón-Montaño, J. M., Orta, M. L., Pastor, N., Pérez-Guerrero, C., Austin, C., … López-Lázaro, M. (2012). The Coffee Constituent Chlorogenic Acid Induces Cellular DNA Damage and Formation of Topoisomerase I– and II–DNA Complexes in Cells. Journal of Agricultural and Food Chemistry, 60(30), 7384-7391. doi:10.1021/jf300999eCOMAN, C., RUGINA, O. D., & SOCACIU, C. (2012). Plants and Natural Compounds with Antidiabetic Action. Notulae Botanicae Horti Agrobotanici Cluj-Napoca, 40(1), 314. doi:10.15835/nbha4017205Zhao, Y., Wang, J., Ballevre, O., Luo, H., & Zhang, W. (2011). Antihypertensive effects and mechanisms of chlorogenic acids. Hypertension Research, 35(4), 370-374. doi:10.1038/hr.2011.195Dos Santos, M. D., Almeida, M. C., Lopes, N. P., & de Souza, G. E. P. (2006). Evaluation of the Anti-inflammatory, Analgesic and Antipyretic Activities of the Natural Polyphenol Chlorogenic Acid. Biological & Pharmaceutical Bulletin, 29(11), 2236-2240. doi:10.1248/bpb.29.2236Stommel, J. R., & Whitaker, B. D. (2003). Phenolic Acid Content and Composition of Eggplant Fruit in a Germplasm Core Subset. Journal of the American Society for Horticultural Science, 128(5), 704-710. doi:10.21273/jashs.128.5.0704Whitaker, B. D., & Stommel, J. R. (2003). Distribution of Hydroxycinnamic Acid Conjugates in Fruit of Commercial Eggplant (Solanum melongenaL.) Cultivars. Journal of Agricultural and Food Chemistry, 51(11), 3448-3454. doi:10.1021/jf026250bProhens, J., Rodríguez-Burruezo, A., Raigón, M. D., & Nuez, F. (2007). Total Phenolic Concentration and Browning Susceptibility in a Collection of Different Varietal Types and Hybrids of Eggplant: Implications for Breeding for Higher Nutritional Quality and Reduced Browning. Journal of the American Society for Horticultural Science, 132(5), 638-646. doi:10.21273/jashs.132.5.638Prohens, J., Whitaker, B. D., Plazas, M., Vilanova, S., Hurtado, M., Blasco, M., … Stommel, J. R. (2013). Genetic diversity in morphological characters and phenolic acids content resulting from an interspecific cross between eggplant,Solanum melongena, and its wild ancestor (S. incanum). Annals of Applied Biology, 162(2), 242-257. doi:10.1111/aab.12017Lester, R. N. (1986). TAXONOMY OF SCARLET EGGPLANTS, SOLANUM AETHIOPICUM L. Acta Horticulturae, (182), 125-132. doi:10.17660/actahortic.1986.182.15Bukenya, Z. R., & Carasco, J. F. (1994). Biosystematic Study of Solanum Macrocarpon—S. Dasyphyllum Complex in Uganda and Relations with Solanum Linnaeanum. East African Agricultural and Forestry Journal, 59(3), 187-204. doi:10.1080/00128325.1994.11663195Polignano, G., Uggenti, P., Bisignano, V., & Gatta, C. D. (2009). 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Enantioselective CE analysis of hepatic ketamine metabolism in different species in vitro

Ketamine, an injectable anesthetic and analgesic consisting of a racemic mixture of S-and R-ketamine, is routinely used in veterinary and human medicine. Nevertheless, metabolism and pharmacokinetics of ketamine have not been characterized sufficiently in most animal species. An enantioselective CE assay for ketamine and its metabolites in microsomal preparations is described. Racemic ketamine was incubated with pooled microsomes from humans, horses and dogs over a 3 h time interval with frequent sample collection. CE data revealed that ketamine is metabolized enantioselectively to norketamine (NK), dehydronorketamine and three hydroxylated NK metabolites in all three species. The metabolic patterns formed differ in production rates of the metabolites and in stereoselectivity of the hydroxylated NK metabolites. In vitro pharmacokinetics of ketamine N-demethylation were established by incubating ten different concentrations of racemic ketamine and the single enantiomers of ketamine for 8 min and data modeling was based on Michaelis-Menten kinetics. These data revealed a reduced intrinsic clearance of the S-enantiomer in the racemic mixture compared with the single S-enantiomer in human microsomes, no difference in equine microsomes and the opposite effect in canine microsomes. The findings indicate species differences with possible relevance for the use of single S-ketamine versus racemic ketamine in the clinic