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V. myrriNus extracts were examined both qualitatively and quantitatively by UV-VIS spectrophotometry and a new RP-HPLC method. The results and Standardislerung der Anthocyanlne In Heldelbeerextrakten durch RP-HPLC und Spektrophotometrie the problems arising from application of these methods for bilbeny anthocyanins determination are discussed. The quality and purity of various extracts is compared.Die Heidelbeerextrakte werden mit Hilfe der Spektrophotometrie und einer neuen RP-HPLC Methode untersucht. Die Anwendung der beiden Methoden in der Bestimmung der Anthocyane wird diskutiert. Die Qualitiit und die Reinheit der Extrakte verschiedener Produzenten werden verglichen. Fruit of bilberry (Vacciniwn myrtillus L., Ericaceae) contain complex mixtures of anthocyanins, i.e. delphinidin, cyanidin, petunidin, and malvidin glycosides'). From the analytical point of view, the anthocyanins have provided a considerable challenge, mainly because of their relative lability. The methds for separation of these compounds require strong acidic media as anthocyanins are stable in such conditions in the form of mi flavylium ions2).The solutions of anthocyanins in acidified methanol or acidified ethanol absorb in the UV-region (maximum about 280 nm) and exhibit a characteristic maximum in the visible region (within the range of 510-560 m~)~) .The results of UV-VIS spectrophotometry of bilberry extracts are shown in Table 1. The extracts varied considerably in the anthocyanin content. The qualities of extracts R and F were much lower than those of extracts P and I. Absorbance values in the W depend also on the presence of other compounds (phenolic acids, tannins etc.). Relatively high values of A"lm of extracts R and F suggest the presence of large amounts of other polyphenols in these samples.Successful separation of phenolic acids and flavonoids by Rp-HPLC led to similar analytical methods for anthocyanidins and anth~cyanins~~). Chromatographic data of anthocyanin separation by our system are specified in Table 2.Phenolic acids, catechins and some proanthocyanidins were eluted during 40 min. The peaks of anthocyanins appeared within the next 50 min. However, when the sample abounded in tannins most of them were eluted together with anthocyanins and the base line drifted.The composition of the extracts, based on RP-HPLC determination, is presented in Table 3. The preponderance of delphinidin glycosides was observed in all the extracts. Extracts I and P had similar composition, moreover we did not find cyanidin-3-0-glucoside in extract P. The,content of

A reversed-phase HPLC methcd is described for the qualitative analysis of HPLC-Analyse der Procyanidine in Crataegus-Extrakt the procyanidin dimer 8-2, oligomeric, and polymeric procyanidins in the Crataegus extract.Eine RP-HPLC Methode fUr die qualitative Bestimmung des dimeren Procyanidins B-2 und der oligomeren und polymeren Procyanidine im Extract von Crataegus wird beschrieben.Flavonoids and oligomeric procyanidins are the main constituents responsible for the biological activity of Crataegus"". Thompson et al?) found (-)-epicatechin, one major procyanidin dimer B-2, a minor procyanidin dimer B-5, a major trimer C-1 and various higher oligomers in hawthorn inflorescence.During storage polymerization of procyanidins occurs and precipitates may be formed in liquid Crataegus preparations6'. These mechanisms are probably due to various interactions between polyphenols and other molecules of the s~lution''~). Polymerization of procyanidins results in reduced therapeutical value of the Crataegus extract and so analytical methods for the evaluation of oligo-and polymers should be developed. A method for separate determination of oligomeric and polymeric procyanidins, based on column chromatography followed by colorimetric measurement was reported by Hiermurzn et al?'.Acidified aqueous solutions of methanol or acetonitrile are common solvents for separation of flavonoids and proanthocyanidins by RP-HPLC'"'. Lea") separated procyanidins in ciders and wines by methanol gradient in aqueous solution of perchloric acid (pH 2.0 -2.5). He estimated the relationship between S (solvent strength) and molecular weight of procyanidins; for lower oligomers S was 3.3, but for polymers the values of S were very high, and the latter compounds were eluted as a broad band after sharp change in gradient steepness. Various proanthocyanidin dimers and trimers were separated by Mulkay et al.I2' and M~Murrough'~).In spite of numerous RP-HPLC studies of Crataegus flav~noids'~-'~), no method for the HPLC analysis of Crataegus procyanidins has been reported. The polyphenolic and polymeric nature of procyanidins raised the question whether they could be successfully separated in the multicomponent mixture of polyphenols. We, therefore, found it of interest to develop a HPLC method for the evaluation of procyanidins in the Crataegus extract. Results and DiscussionInitially, we examined the RP-HPLC solvent systems, consisting of methanol or acetonitrile gradient in 2.5 -5.0% acetic acid. These conditions, though effective in separation of flavonoids, failed in the selective elution of Crataegus procyanidins. We observed that a broad peak of some oligomeric procyanidins overlapped the main peaks of flavonoids. moreover the majority of oligomers and all of the polymers remained on the column, as the concentration of organic modifier in the mobile phase did not exceed 20%.In accordance with Lea's"' results, we found strong acidic conditions and sharp gradient steepness absolutely necessary for the effective elution of Crataegus procyanidin higher ...

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Polish is considered a classic example of a bidirectional stress system with internal lapses. Such systems are typologically rare and were recently hypothesized to be non-existent [1]. Latest studies [2, 3], based on comparisons of paired five-and sixsyllable words, revealed that secondary stress in Polish is iterative and is expressed in terms of onset consonant duration. No acoustic study of Polish words having more than six syllables has been conducted thus far. However, heptasyllabic words, unlike six-syllable words, can be revealing not only about the presence of secondary stress iteration but also about the direction of stress assignment ([(σσ)(σσ)σ(σσ)] vs. *[σ(σσ)(σσ)(σσ)]). The present paper reports on an acoustic study of heptasyllabic words compared to segmentally matched five-and six-syllable words (eight triplets, e.g. acetylenowego acetylenuacetylenowy, collected from eight native speakers of Polish). Four parameters are investigated: onset consonant duration, vowel duration, intensity and fundamental frequency. The results point to the presence of stress on the third syllable of heptasyllabic words, manifested in terms of longer onset consonant duration. This supports traditional descriptions of Polish as a bidirectional stress system.