Effect of different technological processes on the chemical composition of myrtle (<Emphasis Type="Italic">Myrtus communis</Emphasis> L.) alcoholic extracts

Several technological processes were applied to improve the extraction efficiency in the production of myrtle (Myrtus communis L.) liqueur. The variations in the chemical composition of myrtle hydroalcoholic extracts were monitored in a laboratory scale for 40 days after the application of: double dose of berries; ultrasonic extraction; enzymes, to improve either the color or aroma extraction; and atmosphere saturated with nitrogen to improve the stability against oxidative degradations during extraction. Moreover, freezing at −20 °C was applied to myrtle berries as a technological strategy to prolong the use of berries, and macerates were obtained after 4, 8, and 12 months. Chemical investigation of macerates was performed using different analytical methods such as GC and GC-MS for the volatile compounds, HPLC-PDA for free anthocyanins, and spectrophotometric analysis for CIE L*a*b* coordinates and total anthocyanins. Dry matter and pH were also monitored during maceration. Among the different technological processes, the nitrogen-modified atmosphere was the most suitable technique to be applied in industrial scale. An industrial trial was applied with this process and alcoholic extracts and liqueurs have been obtained. The liqueur maintained a higher amount of anthocyanins, better CIE L*a*b* parameters and superior organoleptic characteristics compared to the traditional storage.     

HPLC/DAD/ESI-MS analyses and anti-radical activity of hydrolyzable tannins from different vegetal species

In the present work, several tannin extracts from myrtle and pomegranate were analyzed and characterized using HPLC/DAD/ESI-MS methods. Both aqueous and hydroalcoholic myrtle leaf extracts were found to be rich in galloyl-glucosides, galloyl-quinic acids, ellagitannins and flavonoids. In these extracts we observed a predominance of galloyl-glucosides and galloyl-quinic derivatives with respect to ellagic derivatives; 87.14% and 12.86%, respectively, average gallic and ellagic derivatives with respect to total tannins content. In pomegranate extracts, substantial differences were found in polyphenol contents between peel and seed extracts with regard to the relative abundance of gallic and ellagic acid derivatives: 28.81% and 71.19%, respectively, as average total gallic and ellagic derivatives in peel extracts; 61.30% and 38.70%, in seed extracts. The antiradical properties were evaluated and compared to those of two commercial extracts of chestnut bark and grape seeds. The collected data could suggest the use of myrtle and pomegranate extracts as nutraceuticals and functional foods for their important antioxidant properties.     

Anthocyanins,Antioxidative, and Antimicrobial Properties of American Cranberry (Vaccinium macrocarpon Ait.) and their Press Cakes

ABSTRACT: Amounts of total phenolics, anthocyanins, and ascorbic acid in 4 American cranberry varieties harvested at 4 stages of maturity were measured. The larger amount of phenolic compounds was found in berries of “Black Veil” cultivar (504 mg/100 g) at II stage of maturity. Significantly larger amounts of anthocyanins were determined in the overripe berries of the cultivars “Ben Lear” and “Black Veil.” The amount of ascorbic acid in berries increased during ripening from I to III stage, and slightly decreased in the overripe berries. The biggest quantities of ascorbic acid were found in the ripe berries of “Ben Lear” cultivar (15.8 mg/100 g). The distribution of anthocyanins pigments was determined by HPLC‐UV/MS in mature berries. The composition of individual anthocyanins in berries was quite similar in all the studied cranberry cultivars. While skins of cranberries are rich in anthocyanins and other phenolic compounds, the extracts of the by‐products of cranberries juice—berry cakes, were analyzed and obtained results were compared with the properties of extracts made from whole berries. The anthocyanins and total phenolics content, radical scavenging activity, antimicrobial activity of the whole berries, and their press cakes extracts were measured. All investigated extracts from berries and their press cakes showed good radical scavenging activity and revealed antimicrobial properties. It was found that Bacillus cereus (ATCC 10876) and Micrococcus luteus (ATCC 9341) were the most sensitive among 10 tested Gram‐negative and Gram‐positive bacteria.     

BIOCHEMISTRY OF UNEVEN RIPENING IN GULABI GRAPE1

Physico-chemical changes, organic acids content and activities of enzymes related to softening, glycolytic, gluconeogenic and organic acids metabolism were studied from 70 to 100 days after anthesis in ripening of berries of Gulabi grape. Uneven ripening was observed in 70 day old clusters. The disorder affected 22.76 and 32.38% of berries in bunches harvested at 90 and 100 days, respectively. Unripe berries had less dry matter, sugars, skin anthocyanins and more seed, fresh weight and acidity compared to ripe berries. Green berries had more malic and less tartaric acid, while brown berries had less malic acid and black berries contained more tartaric acid. Green berries contained more polygalacturonase, cellulase, hexokinase, glucose 6-phosphatase, phosphoenol pyruvate carboxylase, pyruvate decarboxylase and polyphenol oxidase activities than ripe fruit. Brown berries contained the highest phosphofractokinase, malate and glutamate dehydrogenase activities, and black berries had the highest activities of pectinesterase, fructose 1,6-bisphosphatase and malic enzyme. The role of dry matter, malic acid, pectinesterase and certain enzymes of gluconeogenic and organic acids metabolism in uneven ripening is discussed.     

Antioxidant capacity and phenolic compounds in commercially grown native Australian herbs and spices

The antioxidant capacities and phenolic composition in six native, commercially grown, Australian herbs and spices were investigated. Tasmannia pepper leaf, followed by anise myrtle and lemon myrtle contained the highest levels of total phenolics (TP; 102.1; 55.9 and 31.4 mg gallic acid equivalents (GAE)/g dry weight (DW), respectively). Tasmannia pepper leaf exhibited the highest oxygen radical absorbance capacity (ORAC assay) followed by lemon myrtle and anise myrtle. Anise myrtle exhibited the highest total reducing capacity [TRC; Ferric Reducing Antioxidant Power (FRAP) assay], followed by Tasmannia pepper leaf and lemon myrtle. Australian bush tomato, with TP content of 12.4 ± 0.9 mg GAE/gDW and TRC of 206.2 μMol Fe⁺²/gDW, resembled the Chinese Barbary Wolfberry fruit. The TP content of Tasmannia pepper berry (16.86 mg GAE/gDW) was similar to that of black pepper, but it’s TRC was 25% lower. Cinnamic acids and flavonoids, tentatively identified by mass spectrometry, were identified as the main sources of antioxidant activities.     

European elderberry (Sambucus nigra L.) rich in sugars,organic acids,anthocyanins and selected polyphenols

Sugars and organic acids in the fruit of two cultivars and three selections of black elderberry (Sambucus nigra L.): ‘Haschberg’, ‘Rubini’, ‘Selection 13’, ‘Selection 14’ and ‘Selection 25’ were quantified. The anthocyanin as well as quercetin profiles of this plant material were also established by the use of HPLC/MS. Significant differences in the concentration of sugars and organic acids were detected between the widely spread cultivar ‘Haschberg’ and all other cultivars/selections; ‘Haschberg’ was the richest in organic acids (6.38 g kg⁻¹ FW), and it contained the least sugar (68.5 g kg⁻¹ FW). The following major cyanidin based anthocyanins were identified in the fruit of black elderberry: cyanidin 3-sambubioside-5-glucoside, cyanidin 3,5-diglucoside, cyanidin 3-sambubioside, cyanidin 3-glucoside and cyanidin 3-rutinoside. The most abundant anthocyanin in elderberry fruit was cyanidin 3-sambubioside, which accounted for more than half of all anthocyanins identified in the berries. The ‘Rubini’ cultivar had the highest amount of the anthocyanins identified (1265 mg/100 g FW) and the lowest amount was measured in berries of the ‘Selection 14’ (603 mg/100 g FW). The ‘Haschberg’ cultivar contained a relatively low amount of anthocyanins in ripe berries (737 mg/100 g FW). From the quercetin group, quercetin, quercetin 3-rutinoside and quercetin 3-glucoside were identified; the latter prevailing in black elderberry fruit. The cultivar with the highest amount of total quercetins was ‘Selection 25’ (73.4 mg/100 g FW), while the ‘Haschberg’ cultivar contained average amounts of quercetins (61.3 mg/100 g FW). The chemical composition of the ‘Haschberg’ cultivar, the most commonly planted, conforms to the standards for sugars, anthocyanins and quercetins and exceeds them in the content levels of organic acids, the most important parameter in fruit processing.     

Some aspects of the quantitative/qualitative assessment of commercial anthocyanin-rich extracts

Colour assessment of anthocyanin-rich extracts according to the legal CE normative involves some important limitations: Lack of objectivity in the assessment of samples with different moisture contents and/or absorption maximums, and inability to identify possible fraudulence due to copigmentation phenomena. To overcome these limitations the following corrections were introduced: Colour intensity CI=CI_λmax, referred to 1 g dry matter; when Abs₇₈₀ > 0.001, CI=CI_λmax−CI₇₈₀, followed by determination of total anthocyanins (TA) by any method using a known standard reference. Pigment qualities were best described by the use of spectral colorimetric assessment. Best objectivity was achieved by the use of the homogeneous CIELAB colour space. Separation of anthocyanins as monomer, and red and yellow–brown polymer fractions by open column chromatography gave important information about the structure/quality relationships of the anthocyanin pigments. HPLC analysis contributed to the identification of the extracts with high acylated anthocyanin contents, related to high physicochemical stability. Determination of total dry matter and total soluble and suspended solids gave a good indication of the purity of the anthocyanin pigments and the possible haze contamination of the coloured product, whereas determination of total catechins and condensed tannins were indicative of possible taste alterations. The main drawback, limiting the use of most of the examined qualitative parameters, was the lack of normalized reference data for anthocyanin-rich extracts.     

Exclusion of sunlight from Shiraz grapes alters wine colour, tannin and sensory properties

The aim of this study was to determine how changes in grape composition brought about by artificial shading (sunlight exclusion) influence wine properties including colour, flavonoid composition and sensory attributes. Prior to flowering, bunches of Shiraz grapes were enclosed in boxes designed to eliminate light without altering bunch temperature and humidity. This artificial bunch shading had little effect on berry ripening and accumulation of sugar but at harvest the shaded bunches had smaller berries and higher seed weight, juice pH and titratable acidity. The amount of anthocyanins in the fruit was not changed significantly but anthocyanin composition in the shaded berries was shifted towards dioxygenated anthocyanins (the glucosides of cyanidin and peonidin derivatives). Shaded fruit had increased seed tannins and decreased skin tannins but the largest relative change in flavonoids was a marked decrease in flavonols in the shaded fruit, similar to previous studies. Wines made from shaded fruit had lower wine colour density, total phenolics, anthocyanins and tannins when the wine was bottled and after ageing for up to three years. Analysis of potential flavour compounds following acid hydrolysis indicated that the wines made from shaded fruit had decreased levels of glycosides of β-damascenone and 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN). Sensory analysis of the wines indicated no significant difference in aroma attributes but the wines made from shaded fruit were rated lower for astringency, fruit flavour and flavour persistence in-mouth sensory attributes. The results indicate that extreme shading of Shiraz fruit can decrease wine colour, anthocyanins and tannins as well as altering sensory attributes.     

Comparative antioxidant activity and 1H NMR profiling of Mediterranean fruit products

In this study the antioxidant activity of methanol extracts obtained from Mediterranean fruit products (prickly pear fruit jam and cream, myrtle berries jam, orange and mandarin-orange marmalades) was evaluated and compared in several in vitro models of oxidative stress. The compositional profile of methanol extracts (carbohydrates, organic acids, amino acids, and main phenolic compounds) was characterized by ¹H NMR spectroscopy and the total phenol content was estimated by the Folin–Ciocalteu procedure. All extracts showed protective effect against thermal-cholesterol degradation, strictly correlated to total phenols. Extracts from prickly pear cream and myrtle berries jam preserved liposomes from Cu^2 +-induced oxidation, inhibiting the reduction of polyunsaturated fatty acids and the increase of malondialdehyde. Extracts from prickly pear cream and citrus marmalades significantly reduced the reactive oxygen species generation induced by tert-butylhydroperoxide in Caco-2 cell culture. The results of this work qualify all tested Mediterranean fruit preserves as a good source of biologically active components with considerable antioxidant potential.     

Influence of osmotic concentration,continuous high frequency ultrasound and dehydration on antioxidants,colour and chemical properties of rabbiteye blueberries

Rabbiteye blueberries (Vaccinium ashei Reade) were osmoconcentrated in a sucrose solution for 12 h, and for 3 h, with and without high frequency ultrasound (CHFU). Treated and untreated samples were air-dehydrated (70 °C, 10 h). Osmoconcentration decreased titratable acidity and induced a high loss of anthocyanins and phenolics. Approximately 60% of anthocyanins and phenolics were lost during osmoconcentration for 12 h. Air-dehydration further decreased anthocyanins and phenolics, with a higher negative influence on anthocyanins. Dehydration, after osmotic concentration, produced the largest colour differences in comparison to the control. High frequency ultrasound had a negative influence on anthocyanins and phenolics. Antioxidant activity was lowest in osmoconcentrated and dehydrated berries. Combination of high temperature, high sugar concentration and oxygen availability had the largest negative influence on colour and antioxidant properties (anthocyanins and phenolics) of dehydrated rabbiteye blueberries.     

Chemical composition and antioxidant activities of Myrtus communis L. berries extracts

Myrtle (Myrtus communis L.) berries extracts were prepared with solvents at different polarity (water, ethanol, and ethyl acetate) and analysed using different in vitro tests in order to evaluate their antioxidant properties. Antiradical and total antioxidant activities were measured with DPPH and FRAP tests, respectively. Their ability to protect biological molecules was assessed using the cholesterol and LDL oxidation assays. In addition, phenolic compounds and unsaturated fatty acids composition was analysed by HPLC–DAD and HPLC–MS/MS. Ethanol and water extracts showed the highest amount of extracted compounds, but the highest antiradical and antioxidant activities were found in ethanol and ethyl acetate extracts. These extracts were also the ones with the highest content of phenolic compounds. In addition, our results showed a highly significant correlation between the amount of total phenols and antiradical (R² = 0.9993) or antioxidant activities (R² = 0.9985) in these extracts. HPLC–DAD and HPLC–MS analyses showed significant quantitative and qualitative differences among these three extracts. The ethyl acetate extract had the highest protective effect in assays of thermal (140 °C) cholesterol degradation and Cu²⁺-mediated LDL oxidation, inhibiting the reduction of polyunsaturated fatty acids and cholesterol, and the increase of their oxidative products. These results suggest that because of these properties, myrtle berries could be used in dietary supplements preparations or as food additives.     

Anthocyanin stability studies in Tibouchina semidecandra L.

The effects of pH, storage period, temperature, light and dark conditions on the stability of anthocyanins extracted from Tibouchina semidecandra flowers of different developmental stages was evaluated. Fully formed but unopened flower bud had the highest amount of total anthocyanin extracted from fresh petals. The anthocyanin contents for all flower developmental stages were stable at pH 0.5–3.0 but the colour of the extracts faded at higher pH values. Degradation percentages of total anthocyanins in the extracts kept at 25 °C were 7–20% lower than that maintained at 31 °C. Extracts stored in darkness at 25 °C maintained their purple colour for 26 days while light exposure reduced it to an average of 10 days. The study shows that suitable storage condition for coloured anthocyanin pigments in extracted form is in acidic conditions in the dark. This implies the potential usage of coloured anthocyanins as natural food colourants and shelf life indicator for acidic foods.     

Anthocyanin composition and anthocyanin pathway gene expression in grapevine sports differing in berry skin colour

The synthesis of anthocyanins was investigated in six grapevine sports with altered skin colour. Cabernet Sauvignon and Shiraz grapes contained anthocyanin monoglucosides as well as acetylated and coumarylated derivatives, predominantly of malvidin, whereas Pinot Noir grapes contained only anthocyanin monoglucosides. Fruit of some sports arising from varieties with black berries either lacked anthocyanins or had much lower levels than their progenitors. A bud sport of Cabernet Sauvignon (Bronze Cabernet) exhibited a 90% reduction in anthocyanin levels, but an anthocyanin composition similar to that of the normal Cabernet Sauvignon fruit. The fruit of a white-coloured bud sport of Bronze Cabernet did not contain anthocyanins. Coloured berries of sports originating on varieties with white-skinned berries also had lower levels of anthocyanins than black grapes, but like Pinot Noir contained very low levels of acylated anthocyanins. The berries of these sports also varied in the proportions of the different types of 3-monoglucosides they contained. The results suggest that control of 3-monoglucoside synthesis and modification vary in the sports. The expression of six genes from the flavonoid biosynthetic pathway was determined. Some genes were expressed in all grapes, even where little or no anthocyanins accumulated, but expression of the gene encoding a UDP glucose-flavonoid 3-o-glucosyl transferase (UFGT) was only detected in coloured grapes that synthesised anthocyanins. Southern and northern analysis of the white grapes indicated that the UFGT gene was present but was not expressed. Thus the lack of anthocyanins in white-skinned varieties or sports correlates with a lack of expression of the UFGT gene, although the expression of some other flavonoid pathway genes was also decreased.     

Flavonoids and C13-norisoprenoids in Vitis vinifera L. cv. Shiraz: relationships between grape and wine composition,wine colour and wine sensory properties

Background and Aims: This study investigated flavonoid composition and C₁₃-norisoprenoids (β-damascenone and β-ionone) in Shiraz grapes and wines, their relationships and links to wine sensory properties. Methods and Results: Differences in the grape berry flavonoid profile were created by exposing bunches to varying levels of sunlight intensity through canopy manipulation. Grapes were harvested at similar maturity and three replicate wines were made for each treatment in both vintages. Grapes produced under shaded canopy conditions had reduced anthocyanins and skin tannins, but little effect on seed tannins was observed. Pigmented polymers and tannins in wines were related to berry flavonoid composition (anthocyanins, skin and seed tannins, and their ratios). In grapes and wines, no significant effects were observed in response to canopy manipulation for two hydrolytically released C₁₃-norisoprenoids, β-damascenone and β-ionone. Relationships were established for wine flavonoid composition, wine colour density, sensory perception of the astringency-related mouth-feel attributes and a quality scale. A positive relationship between wine quality score and hydrolytically released β-damascenone in both berries and wines was found, but not for free β-damascenone or any quantified forms of β-ionone. Conclusion: Higher concentrations of anthocyanins and skin tannins in berries, coupled with a lower concentration of seed tannins were associated with higher wine quality. The ratio anthocyanins*skin tannins/seed tannins is proposed as an indicator of wine flavonoid composition, wine colour and wine quality. Excessive canopy shade was detrimental to berry and wine composition and intensified sensory detection of ‘straw’ and ‘herbaceous’ characters in the wines. Significance of the Study: This study increases the understanding of the balance and composition of flavonoid compounds and C₁₃-norisoprenoids in berries and their relationship with wine composition and wine sensory properties, but also highlights the importance of a canopy microclimate assessment.     

Elevated temperature decouples anthocyanins and sugars in berries of Shiraz and Cabernet Franc

Background and Aim: We tested the hypothesis that elevated temperature decouples anthocyanins and total soluble solids (TSS) in developing berries and explored the effects of fruit load and water supply on the putative decoupling. Methods and Results: We established three 2² factorial experiments where two thermal regimes (elevated temperature, control) where combined with varieties (Shiraz, Cabernet Franc), fruit loads (bunch removal, control) or water regimes (irrigated, water deficit). The relationship between anthocyanins and TSS had a lag phase where TSS increased with no change in anthocyanins and an approximately linear phase where both traits increased in parallel for TSS > 11.4°Brix. Mean residuals in the linear phase were 0.065 mg/g in controls compared with ?0.064 mg/g in the heated treatment, hence demonstrating the thermal decoupling of anthocyanins and TSS across varieties fruit loads and water regimes (P < 0.0001). Delayed onset of anthocyanin accumulation at elevated temperature explained the decoupling. Water deficit increased the anthocyanin : TSS ratio. Conclusion: Elevated temperature decoupled anthocyanins and sugars in berries by a relative shift in onset rather than rate of accumulation of these berry components. Significance of the Study: Warming trends are likely to disrupt the anthocyanin : sugar ratio in berries with consequences for colour : alcohol balance in red wines. Water deficit established shortly before veraison could partially restore these ratios.     

Relationships between seed and berry development of Vitis Vinifera L. cv Shiraz: Developmental changes in seed morphology and phenolic composition

Berries were collected regularly from fruit set to berry maturity from irrigated (Shiraz) grapevines in a Barossa valley vineyard. Seeds were removed for detailed study of physical attributes (weight, moisture, colour) and phenolic composition (seed tannins). Three phases of seed growth and development were discerned: (1) a phase of seed growth characterised by a steady increase in both fresh weight and dry weight, biosynthesis and accumulation of flavan‐3‐ols and tannins, and green appearance; (2) a transition phase where seed fresh weight and dry weight reached a maximum, but with continuing enlargement of the basal end. Accumulation of flavan‐3‐ols and seed tannins also reached a maximum during phase 2, and was accompanied by an onset of tannin oxidation, and yellow appearance; and finally, (3) a phase of seed drying and maturation defined by a decrease in fresh weight due to water export, a sustained oxidation of tannins, and overall brown appearance. These phases in seed development correspond to particular stages in berry development. Seeds reached maximum fresh seed weight and full size at the beginning of berry colouring (veraison), while maximum dry seed weight coincided with maximum berry weight. Changes in seed phenolics were linked to berry development and maturation. Changes in seed coat colour were also related to developmental changes in berry anthocyanins and total skin phenolics, indicating that the external appearance and colour of the seed coat may be used as an additional indicator of overall berry ripeness. A graduated colour chart was developed to provide an objective index of seed coat colour and thus developmental status of seeds and berry.     

Evaluation of garlic ecotypes for allicin and other allyl thiosulphinates

An aqueous extraction method coupled with ultra performance liquid chromatography with photo diode array detection was optimised and validated for screening of 93 garlic ecotypes for allicin and other allyl thiosulphinate contents. Variability in allicin, allyl methyl thiosulphinate and allyl trans-1-propenyl thiosulphinate was observed both on fresh and dry weight basis. Bulb to bulb variation for allicin levels was less in clonal selections followed by commercial varieties, exotic line and landraces, respectively. Five ecotypes on fresh weight basis and all the ecotypes on dry weight basis had allicin contents more than the recommended pharmacological values (?4.5 mg g⁻¹). Cluster analysis and principal component analysis results revealed that geographical origin, breeding status and colour did not play any role in ecotype clustering. This study is useful as a base for selection of garlic ecotypes as a dependable raw material source for pharmaceutical and food processing industries.     

Qualitative und Quantitative Analyse der Anthocyane in Schwarzen Apfelbeeren (Aronia melanocarpa Michx. Ell.) mittels TLC, HPLC und UV/VIS-Spektrometrie

Total anthocyanin content and qualitative and quantitative anthocyanin composition in black chokeberries [Aronia melanocarpa (Michx.) Elliott] were determined by TLC, HPLC and UV/VIS methods. After ethanol extraction and cleaning operations we found, in different varieties of black chokeberries (Nero, Rubina and Viking), between 650 mg and 850 mg total anthocyanins per 100 g dry weight. The anthocyanin composition was analysed; (cyanidin was the only aglycon (anthocyanidin) found and the monosaccharides galactose (68.9%), arabinose (27.5%), xylose (2.3%) and glucose (1.3%) were identified. The quantitative distribution is given in parentheses. In comparison with other berries and fruits, which are rich in anthocyanins, black chokeberries have a simple anthocyanin spectrum, but a many times higher anthocyanin content. For that reason chokeberries are of special interest as a source for a natural colourant.     

‘蓓蕾’蓝靛果中花色苷组成鉴定及抗氧化能力比较分析

对蓝靛果中花色苷的组成进行鉴定,并对其抗氧化能力进行比较分析。实验以蓝靛果（‘蓓蕾’品种）为原料,采用有机溶剂60%乙醇（0.1%盐酸酸化）溶液,超声辅助提取90 min;利用D101大孔树脂对获得的粗提物进行纯化,之后冷冻干燥制得粉末物质。通过pH示差法和福林-酚法分别测定总花色苷含量和总多酚含量,分别为（353.35±0.79）、（474.01±2.12）mg/g;并用高效液相色谱-质谱联用法对花色苷组成进行鉴定,共发现11 种花色苷,其中矢车菊-3-葡萄糖苷为主要花色苷（90.679%）。此外,实验还通过总抗氧化能力测定和2,2’-联氨-二（3-乙基苯并噻唑-6-磺酸）二铵盐自由基、1,1-二苯基-2-三硝基苯肼自由基清除能力测定,比较分析蓝靛果花色苷提取物、矢车菊-3-葡萄糖苷、VC的抗氧化能力,结果表明,3 种物质的抗氧化能力排序为：矢车菊-3-葡萄糖苷＞花色苷提取物＞VC。     

Qualitative und Quantitative Analyse der Anthocyane in Schwarzen Apfelbeeren (Aronia melanocarpa Michx. Ell.) mittels TLC,HPLC und UV/VIS-Spektrometrie

Total anthocyanin content and qualitative and quantitative anthocyanin composition in black chokeberries [Aronia melanocarpa (Michx.) Elliott] were determined by TLC, HPLC and UV/VIS methods. After ethanol extraction and cleaning operations we found, in different varieties of black chokeberries (Nero, Rubina and Viking), between 650 mg and 850 mg total anthocyanins per 100 g dry weight. The anthocyanin composition was analysed; (cyanidin was the only aglycon (anthocyanidin) found and the monosaccharides galactose (68.9%), arabinose (27.5%), xylose (2.3%) and glucose (1.3%) were identified. The quantitative distribution is given in parentheses. In comparison with other berries and fruits, which are rich in anthocyanins, black chokeberries have a simple anthocyanin spectrum, but a many times higher anthocyanin content. For that reason chokeberries are of special interest as a source for a natural colourant.