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considered as evaluation criteria. The highest yields of hydrophilic extrac- tives were found in barks of grey alder and aspen (36.8 and 22.9%, respectively). In the former, the highest antioxidant activity was found towards free radicals (DPPH• and ABTS•q) and superoxide anion radical. Open chain diaryl- heptanoids, mainly oregonin, were identified as the major constituents of the grey alder hydrophilic extract. In addition to oregonin, the presence of 2 linear diarylheptanoids wpla- typhylloside and 1,7-bis-(3,4-dihydroxyphenyl)-heptane-5- O-b-D-glucopyranosidex was

: Substances used as standards (hirsutanonol-5- O - β - d -glucopyranoside, rubranoside A, oregonin, platyphylloside, alnuside A and hirsutanonol; Figure 1 ) have previously been isolated from the bark of A. glutinosa ( Novaković et al. 2013 ). Ethanol (96%) for extraction of plant material was freshly distilled. Solvents for ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis (chromatographic grade) were purchased from Sigma-Aldrich (St. Louis, USA). Plant material: Field botanical determination of individuals was based on the species

-glucopyranoside, oregonin, hirsutanonol, alnuside A, platyphylloside and rubranoside A) (Figure 3) were isolated from the bark of A. glutinosa ( Novaković et al. 2013 ). The extraction solution (96% EtOH, Reahem, Novi Sad, Serbia) was freshly distilled. Solvents for ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis were of chromatographic grade (Sigma-Aldrich, St. Louis, MO, USA). Plant material Qualitative and quantitative secondary metabolite variation in a species is influenced by several factors, such as plant age and size, tissue type

on the extract) of the extract. The polyphenolic compounds identified are listed in Table 1 with the most abundant ones being catechin, catechin dimer, catechin trimer, hydroxyoregonin and oregonin. All these compounds are biologically active natural antioxidants and antimicrobial agents, which can be used as ingredients in formulation of different medications. The predominant chemical constituents in OPCE from goat willow were catechin and catechin dimer (procyanidin B-type dimer), which explains the high antioxidant activity of this extract (Table 2 ). Table 1

type can be excluded. Biochemical aspects are very important, because enzymatic reactions can occur both in sapwood and to some extent even in heartwood. The orange dis- coloration of Alnus is an example, for Holzforschung / Vol. 45 /1991 / No. 2 Copyright © 1991 Walter de Gruyter · Berlin · New York 80 J. Bauch, H. v.Hundt, G. Weißmann, W. Lange and H. Kübel Holzforschung polyphenoloxidases inducing the production of oregonin (Hrutfiord and Luthi 1981). Chemical reactions are mainly associated with the influence of temperature, moisture and oxygen. Also, metal ion

of oxygen, enzymes and probably an energy-source and buffered conditions. The fact that browning occurred in aqueous extracts with oxygen alone indicates that these other factors are not necessary for the reaction de- scribed above in the blackwood extracts. However, this reaction may produce slightly different products to the in vivo browning reaction given that peak S1 was not formed. In studies of alder wood staining, reactions be- tween epicatechin and oregonin (which produce the characteristic orange stain) occurred slowly with the presence of air or H2O2 but

, namely, diarylheptanoids ( Figure 1 , such as oregonin, hydroxyoregonin, Platyphylloside, and curcumin), should also be included into the study as well-known antioxidants. Linear diarylheptanoids and lignins are biosynthesized by the same pathway. Besides, they have a lot of structural similarities. They contain aliphatic chains, connected with the aromatic ring and similar functional groups (C=O and OH groups on side chains, and OCH 3 groups on aromatic rings). Both isolated lignins and diarylheptanoids are often connected with polysaccharides. The expectation is

, they reinforce the sense of full a¤ectedness of the PATIENT. Consequently, a place partici- pant cannot be cast convincingly as a transitive PATIENT (i.e., an entity acted upon by a causer) without the additional help of a perfective read- ing; alternations of the kind Californians like to shop Oregon/in Oregon are not possible without added prefixation on the verb. This behavior is also consistent with the fact that English-like passive targets most natu- rally perfective verbs: passivization is a semantically restricted process in Czech, applicable only to strongly

made in Beaver- ton, Oregon—in design, materials, assortments, and demand forecasting—have 104 C H A P T E R 6 been reshaped by a commitment to improving conditions in the supply chain.¹⁵ Tough conversations and expansive innovation are signatures of the approach that Nike has developed over the years. The disappointing news is that over the fi rst half of the 2000s, according to Nike’s own auditing measures, most factories did not improve in their compli- ance. However, Locke identifi ed some conditions under which compliance was the highest. In particular