Kg-1 Fresh Weight Research Articles

The Characters and Health Risk Assessment of Vegetable Pb in Jilin Suburb

Abstract 108 vegetable samples were collected from Jilin suburb vegetable production base, and Pb of samples was measured using graphite furnace atomic absorption spectrophotometer (GF- AAS). Results showed that the average Pb of vegetable was 0.06 mg·kg-1 fresh weight, with only 1.5% above the Safety Requirements. Single-factor contaminant index was utilized for assessment. It was found that vegetable Pb order as following: leaf vegetables>fruit vegetables, dark vegetables>light vegetables. The average daily intake (DI) Pb of per standard person was urban 21.6 μg •d-1 and rural 18.7 μg •d-1, as well as economical family 22.1 μg •d-1and poor 18.3 μg •d-1, indicating that vegetable Pb in Jilin suburbs were safety. The Pb health risk was assessed based on the target hazard quotients (THQ). The study showed that THQurban =THQhigh >THQmedium >THQlow =THQrural, indicating the health risk via vegetable consumption in rural was relative lower than that in urban area. Assessment results proved that the vegetables Pb in this area is no health risk to persons.

Bioaccumulation of Microcystins in Lettuce.

The contamination of lettuce (Lactuca sativa L.) by water-borne crude extracts of the cyanobacterium microcystin-producing Microcystis aeruginosa (Kützing) Kützing was investigated. The aim of the study was to determine whether bioaccumulation of microcystins occurs in lettuce foliar tissue when sprayed with solutions containing microcystins at concentrations observed in aquatic systems (0.62 to 12.5μg·L(-1) ). Microcystins were found in lettuce foliar tissues (8.31 to 177.8μg per Kg of fresh weight) at all concentrations of crude extracts. Spraying with water containing microcystins and cyanobacteria may contaminate lettuce at levels higher than the daily intake of microcystins recommended by the World Health Organization (WHO), underscoring the need to monitor such food exposure pathways by public authorities.

Flagellin produced in plants is a potent adjuvant for oral immunization

The aim of this study was to produce adjuvant with high biosafety, efficacy and low cost. Towards this goal, the plant Nicotiana benthamiana transient expression system was successfully used to express Salmonella typhimurium's flagellin (FljB). The yield of the expressed FljB was 280mg per kg of fresh weight (FW) leaves. The lyophilized plant powder containing plant expressing FljB was mixed with ovalbumin (OVA) and used for oral immunization of BALB/c mice. The ELISA analysis showed higher and accelerated OVA-specific serum antibody responses in mice given the mixture when compared to animals receiving OVA alone. Furthermore, FljB elicited a mixed Th1/Th2 response as shown by the presence of specific anti-OVA IgG1, IgG2a and IgG2b isotypes. OVA-specific IgAs were also detected in mice given the mixture. Cell-mediated immune response to OVA was induced by FljB as determined by a spleen lymphocyte specific proliferation test. No immune response was generated against FljB. In conclusion, our results showed for the first time the production of FljB in plants and the efficient use of the crude lyophilized extract as an adjuvant for oral immunization.

Yield and quality of garden cress affected by different nitrogen sources and growing period

The effects of different months of the year and nitrogen sources on garden cress (Lepidium sativum L.) yield, quality and nitrate accumulation were investigated during the years 2002 and 2003. In both years, seeds were sown on the first days of September, October, November, January, February and March. Three different nitrogen sources were used: Farmyard (cattle) manure (100 ton·ha-1), Ca(NO3)2-15.5% N (150 kg N·ha-1) and (NH4)2SO4)-21% N (150 kg N·ha-1). Yield, leaf color, dry matter, vitamin C, total glucosinolate content and nitrate accumulation were assessed. No interaction between sowing date and nitrogen form was observed for any of the assessed parameters. Growing period affected all parameters significantly. Plants obtained from January and February sowings resulted in better yield, leaf color, dry matter and vitamin C content. But the nitrate contents also increased. Highest total glucosinolate content was observed during the warmer months. Nitrate nitrogen application increased yield, leaf greenness, vitamin C and nitrate content while farmyard manure application raised dry matter and total glucosinolate contents. Nitrate content of the garden cress plants did not exceed 391 mg kg-1 fresh weight, which is below the accepted daily intake of 3.7 mg nitrate per kg-1 bodyweight set by European Commission’s Scientific Committee on Food. Key words: Lepidium sativum L., farmyard manure, nitrate, glucosinolate, vitamin C.

Transfer of elements to owls (Tyto Alba, Strix Aluco)determined using neutron activation and gamma analysis

The IAEA has recently collated data for a handbook on transfer of radionuclides to wildlife (pending publication as a Technical Reports Series (TRS) document, see Howard et al. (2011)). During this process key data deficiencies were identified, one of which is the lack of data for many elements for birds. The majority of the available transfer data for birds are for game species (e.g. Lagopus spp.) and small song birds. The aim of this study was to consider the feasibility of using a predatory bird sample archive to derive whole organism concentration ratio (CRwo-soil) values for owls for a range of elements relevant to radiological assessments. The CRwo-soil is defined here as the ratio between the concentration of an element/radionuclide in owls (whole organism), measured in Bq kg-1 or mg kg-1 fresh weight (fw) and the concentration of the same element/radionuclide in soil, measured in Bq kg-1 or mg kg-1 dry weight (dw). The Barn (Tyto alba) and Tawny (Strix aluco) owls were selected as examples of a widespread, terrestrial, predatory bird for which archived samples from 2008 were available from the Predatory Bird Monitoring Scheme (PBMS). Their predominant habitats are rough grassland, field and watercourse ‘edges’, and grass strips alongside woods. They have an average home range of approximately 3 km2 and their diet is predominantly rodents (especially voles) and small birds (Taylor, 1994). The PBMS scheme (http://pbms.ceh.ac.uk/) is a long-term (1970 onwards), large scale project which holds a sample archive of 32000 tissues and eggs of predatory birds from throughout the UK. Its aim is to quantify accumulation of contaminants and their effects in predatory birds. The birds submitted to the project have been found dead, usually from road accidents.

Assessment of mercury contamination of the Svitava and Svratka rivers and muscle of chub (Leuciscus cephalus L.) in the urban agglomeration of Brno in the Czech Republic

This study focused on the total mercury and methylmercury content in the muscle of chub (Leuciscus cephalusL.), the total mercury in the river sediments and the evaluation of health risks associated with fish contamination. Chub were caught at seven localities on the Svratka and Svitava rivers in the agglomeration of Brno in 2008. The results were compared to those obtained from the same sites in 2007. Total mercury was determined by atomic absorption spectrophotometry using an AMA 245 analyzer, and methylmercury was determined by gas chromatography (using an electron-capture detector) after acid digestion and toluene extraction in chub muscle. The highest concentrations of total mercury and methylmercury (0.12 ± 0.14 and 0.07 ± 0.02 mg·kg-1fresh weight, respectively) were found in Svratka before junction (south of Brno), whereas the lowest concentration of mercury and methylmercury in chub (0.06 ± 0.01 and 0.04 ± 0.01 mg·kg-1) was detected in Svitava before junction with the Svratka River. Total mercury in sediments ranged from 0.01 to 1.05 mg·kg-1dry weight, the highest value was detected in the sediment from Rajhradice. The lowest content (0.01 mg·kg-1) was at Kníničky. Hazard indices calculated for the selected localities showed no health risk for either a standard consumer or a fishing family. Fish from the Svitava and Svratka rivers show very low mercury concentration and hazard index and their consumption poses no health risk from total mercury and methylmercury contamination.

Characterization and Quantification of Polyphenols in Amazon Grape (Pourouma cecropiifolia Martius)

The phenolic profile of Amazon grape fruit (Pourouma cecropiifolia Martius) was investigated by high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS/MS). For this purpose, suitable extraction and liquid chromatographic methods were developed. Anthocyanins, flavonols and chlorogenic acids were found mainly in the peel. Besides the main anthocyanins, i.e. delphinidin 3-glucoside, cyanidin 3-glucoside and cyanidin 3-(6"-malonyl)glucoside, several minor anthocyanins were identified in the peel. Among these, cyanidin 3,5-diglucoside, delphinidin 3-galactoside, cyanidin 3-rutinoside, cyanidin 3-(3"-malonyl)glucoside, malvidin 3-glucoside, pelargonidin 3-glucoside, peonidin 3-glucoside and petunidin 3-glucoside were characterized on the basis of their fragmentation patterns in MS/MS experiments. The total anthocyanin content in the peel was 420.26±3.07 mg kg(-1) fresh weight. The pulp contained mainly 5-O-caffeoylquinic acid (210.39±3.43 mg kg(-1) fresh weight). Rutin was the predominant flavonol found in Amazon grape (peel 155.45 ± 2.06 mg kg(-1) fresh weight and pulp 2.64±1.21 mg kg(-1) fresh weight). Total polyphenols content was higher in the peel than in the pulp.

Characterization and Quantification of Polyphenols in Amazon Grape (Pourouma cecropiifolia Martius)

The phenolic profile of Amazon grape fruit (Pourouma cecropiifolia Martius) was investigated by high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS/MS). For this purpose, suitable extraction and liquid chromatographic methods were developed. Anthocyanins, flavonols and chlorogenic acids were found mainly in the peel. Besides the main anthocyanins, i.e. delphinidin 3-glucoside, cyanidin 3-glucoside and cyanidin 3-(6”-malonyl)glucoside, several minor anthocyanins were identified in the peel. Among these, cyanidin 3,5-diglucoside, delphinidin 3-galactoside, cyanidin 3-rutinoside, cyanidin 3-(3”-malonyl)glucoside, malvidin 3-glucoside, pelargonidin 3-glucoside, peonidin 3-glucoside and petunidin 3-glucoside were characterized on the basis of their fragmentation patterns in MS/MS experiments. The total anthocyanin content in the peel was 420.26 ± 3.07 mg kg-1 fresh weight. The pulp contained mainly 5-O-caffeoylquinic acid (210.39 ± 3.43 mg kg-1 fresh weight). Rutin was the predominant flavonol found in Amazon grape (peel 155.45 ± 2.06 mg kg-1 fresh weight and pulp 2.64 ± 1.21 mg kg-1 fresh weight). Total polyphenols content was higher in the peel than in the pulp.

Ingestion of U(nat),226Ra,230Th and210Po in vegetables by adult inhabitants of Bagjata uranium mining area, Jharkhand, India

Ingestion of radionuclides through food intake accounts for a substantial part of radiation doses and vegetables constitute essential components of the diet, by contributing protein, vitamins, iron, calcium and other nutrients. Radionuclides can be apprehended in the ecosystem of the East Singhbhum region which is known for its viable grades of uranium. In the present study, vegetables were collected from the villages around the proposed Bagjata mining area and analysed for U(nat), 226 Ra, 230 Th and 210 Po. The geometric mean concentration of U(nat), 226 Ra, 230 Th, and 210 Po were 0.05, 0.09, 0.17 and 1.12 Bq kg-1 fresh weight, respectively. The intake of the radionuclides from vegetables was found to be 49.58 Bq y-1 while the ingestion dose was calculated to be 11.51 µSv y-1 , respectively. The estimated doses are reflecting the natural background dose via the route of ingestion, which is much below the 1 mSv limit set in the new ICRP recommendations. It is lower than the global average annual radiation dose of 2 400 µSv to man from the natural radiation sources as proposed by UNSCEAR. The total cancer risk due to the consumption of vegetables was calculated to be 6.65 × 10-9 which is negligible and much lower than the threshold risk value of 10-6 . The study also reveals that water is more conducive for high radioactivity occurrence in vegetables compared to soil systems.

Content of Selected Flavonoids in 100 Edible Vegetables and Fruits

The objective of this work was to quantify the potential anticancer flavonoids (quercetin, kaempferol, isorhamnetin, apigenin and luteolin) by a rapid, reliable and accurate reverse phase high performance liquid chromatography (RP-HPLC) among 100 edible vegetables and fruits commonly consumed in Harbin city, China. The predominant flavonoids found in the largest abundance in all of the analyzed foods were kaempferol, followed by luteolin and quercetin. The maximum content of quercetin, kaempferol, isorhamnetin, apigenin, luteolin and total flavonoids in foods amounted to 379.7±19.7mg kg-1, 482.0±21.0mg kg-1, 333.6±14.4mg kg-1, 139.3±5.2mg kg-1, 179.5±10.6mg kg-1 and 853.0mg kg-1 fresh weight (FW), respectively. Potherb mustard, lettuce (red), toona leaf, celery leaf, garlic, garlic stalk, apple, date, ginger (with peel) and radish leaf (red root, small) were major food sources of flavonols and flavones. This study contribute to the establishment of China's flavonoid database and provide a basis for the assessment of the daily flavonoid intake.

The Effect of Propagule Type on Yacon Propagation, Growth and Development in Mississippi

Diet-related chronic diseases such as diabetes, high blood pressure, and colon cancer are growing problems in industrialized countries and obesity is the major cause with 36 million deaths annually in the world. Yacon, Smallanthus sonchifolius, (Poepp. et Endl.) H. Robinson, is a root crop and is a rich source of phenolic compounds and dietetic oligofructans with low glucose content [2]. These constituents have shown efficacy in the treatment and prevention of diet-related chronic diseases, including gastrointestinal disorders and diabetes. The objective of this study is to develop an integrated system that promotes yacon as a sustainable root crop industry in Mississippi, including root and leaf production, as well as processing yacon into value added commodities as functional food. Yacon is native to Peruvian Andes and originally grows at elevation 1800–2800 of meters above sea level (masl) [1]. The purpose of our work is to evaluate Yacon growth in Mississippi during the hot and dry summers at elevation of 137.8 masl. Yacon propagules were produced by tissue culture and by stem cuttings. Miicropropagated plantlets adapted to soil conditions at an average of 90%. A significant difference on plant height, number of roots, leaf and root biomass was noticed for plants cultivated in pots which were produced by tissue culture. Only plants produced from stem cuttings were planted in the field and during the first growing season the average yield reached 0.755 kg of fresh weight per plant. Acknowledgements: Thanks go to Mr. Mark Baker, the resident Director of UM Biological Field Station, for preparing the field for yacon plantings and Ms. Michelle Edwards for taking several pictures. This research work was partially supported by the USDA/ARS Cooperative Research Agreement No. 58-6408-2-009.

Changes in glycoalkaloid composition during potato processing: Simple and reliable quality control by HPTLC

An HPTLC method has been established for analysis of α-solanine and α-chaconine in potatoes during industrial processing. Chromatography is performed on silica gel plates in a horizontal developing chamber. Post-chromatographic derivatization by dipping the plates into antimony(III) chloride solution and subsequent heating results in red chromatographic bands. The reaction products are detected and quantified densitometrically by reflectance scanning at 560 nm. The limit of quantification is approximately 30 ng per zone. Depending on the matrix of the sample, the detection limit for both compounds is between 5 and 20 ng per zone. The calibration plots for α-solanine and α-chaconine are linear in the range 30 to 700 ng. Polynomial regression with low relative standard deviation is possible from 30 to 1500 ng. Easy sample preparation, ruggedness, and high selectivity are outstanding advantages of this method. The method is applicable to samples at all stages of processing - raw, peeled, blanched, cooked, and dried potatoes, and byproducts such as peel, waste mash, and processing waters. After steam-peeling, the total glycoalkaloid (TGA) concentration in the analyzed cultivar Karlena was reduced to approximately 25% of its original content in the whole potato, which can increase to more than 1000 mg TGA kg-1 fresh weight. Because of further leaching during processing, the commercial potato flakes tested contained less than 6 mg TGA kg-1 reconstituted mashed potatoes. Food with TGA concentrations of up to 100 mg kg-1 is regarded as completely safe. The ratio of α-chaconine to α-solanine was between 4:1 to 2:1 for all the samples analyzed.

Yield formation and quality characteristics of early potatoes during a short growing period

The effects of nitrogen fertilization on the yield and quality of early potato (Solanum tuberosum L.) were studied at MTT Agrifood Research Finland during 1996–1997. Cultivars were harvested at three times. The experimental layout was a split-split-plot with harvest times as main plots and nitrogen fertilization and potato cultivars as the subplots. The fertilizer treatments were 60 and 120 kg N ha-1 and the cultivars tested were Timo, Gloria and Van Gogh. The harvest times were 57–62, 70–75 and 85–90 days after planting. Application of 120 kg N ha-1 intensifi ed canopy development and increased leaf area of the stands. At early harvest the tuber yield of all cultivars receiving the higher nitrogen application increased by 0.5–2.5 t ha-1. The highest yielding cultivar was Timo. At last harvest, the higher nitrogen treatment increased yield by 3.0–6.2 t ha-1. The highest yielding cultivars were Timo and Van Gogh. The dry matter content of tubers was very low, 13.8–17.2%, at the fi rst harvest and the higher nitrogen application reduced dry matter content by 0.3–1.0%. The highest fertilizer application rate resulted in the largest tuber size. Nitrogen application, however, affected the quality of potatoes by decreasing the dry matter content. The nitrate content in tubers increased signifi cantly with the increasing level of nitrogen. The range of nitrate content in tubers fl uctuated between 13 and 189 mg kg-1 fresh weight showing good controlling of nitrate values. Harvest time affected sucrose content and the reducing sugar content in tubers, but nitrogen fertilizer did not change the sugar content of tubers. As tuber yield and quality during a short growing season are affected mainly by intercepted radiation, methods to increase tuber yield should focus on reducing the time to emergence, improving haulm growth after emergence and increasing the harvest index.;

Mercury and Methylmercury Concentrations in Muscle Tissue of Fish Caught in Major Rivers of the Czech Republic

The aim of the study was to evaluate mercury contamination at twelve outlet sites of rivers in the Czech Republic (Labe, Ohře, Vltava, Berounka, Sázava, Otava, Lužnice, Svratka, Dyje, Morava and Odra). As an indicator, we used muscle tissue of the chub (Leuciscus cephalus) caught at selected sites in 2007. A total of 96 fish were examined. Total mercury was determined by atomic absorption spectrophotometry using the AMA 254 analyzer and methylmercury was determined by gas chromatography with electron-capture detection. Total mercury (THg) and methylmercury (MeHg) concentrations ranged 0.039–0.384 mg kg-1 fresh weight and 0.033–0.362 mg kg-1 fresh weight, respectively. Mercury bound in methylmercury (HgMe) made up on average about 82.2% of total mercury. The highest mercury concentrations were found in fish from Obříství, a site on Labe (THg 0.263 ± 0.086 mg kg-1; MeHg 0.256 ± 0.084 mg kg-1). Mercury concentrations in fish from rivers that cross the borders of the Czech Republic (Labe, Odra and Morava) were low. The Czech Republic therefore does not contribute significantly to river pollution outside its national borders. Hazard indices of the sites monitored were well below 1, and reached 1.365 only in Obříství on Labe for fisherman’s family members (i.e. in the case of annual consumption of 10 kg fish). This indicates possible hazards involved in eating meat of fish caught in that location. Based on PTWI for methylmercury, the maximum amount of fish meat allowed for consumption per week was calculated. The site with the lowest value was Obříství on Labe (0.44 kg). The results of this study present a partial contribution to health risk assessment on the major rivers in Czech Republic.

Hallazgo de mercurio en peces de la Ciénaga de Ayapel, Córdoba, Colombia

Objetivo. Determinar las concentraciones de mercurio total (Hg-T) en algunas especies de peces de la ciénaga de Ayapel (Colombia). Materiales y métodos. Los muestreos fueron realizados desde Julio de 2004 a Junio de 2005, incluyendo las épocas seca y lluviosa. Las muestras fueron analizadas por espectrometría de absorción atómica por vapor frío después de digestión ácida. Resultados. Las concentraciones más altas de Hg-T se observaron para las muestras analizadas de la especie carnívora Ageneiosus caucanus (0.504±0.103 mg Hg kg-1 peso fresco), y las menores concentraciones en la especie Iliófaga Prochilodus magdalenae (0.130±0.056 mg Hg kg-1 peso fresco). Las concentraciones más altas fueron encontradas en las muestras de la época seca. Los niveles promedio de Hg-T en las muestras de peces no excedieron el límite para consumo humano establecido por la Organización Mundial de la Salud (OMS, 0.5 mg Hg Kg-1 peso fresco). Conclusiones. La evaluación del riesgo basado en el índice de peligrosidad sugiere que el consumo de 0.12 kg de pescado por día en la población humana (principalmente carnívoros) podría incrementar el riesgo de envenenamiento por mercurio en la población local.

Appreciation of ethrel on ripening dynamic and on the content of ingredients in processing tomato (Lycopersicon lycopersicum (L.) Karsten) varieties

Tomato (Lycopersicon lycopersicum (L) Karsten) is an important crop cultivated in Hungary. Ethrel has been used to advance maturity and promote uniform ripening of processing tomato since 25-30 years in Hungary. The aims of the present study were 1) to evaluate the effects of two different ethrel concentrations on ripening rate, 2) to investigate lycopene content of different maturity stages, 3) to test the effect of ethrel on lycopene content. It is important to note that the experimental year (in July and August) was very rainy and cool. Ethrel was applied at two rates: 1500 and 3000 ppm. The results clearly indicate that Ethrel can be a useful and effective tool of maturity-enhancement, under present circumstances. Ripening concentration increased significantly by Ethrel. In spite of this, Ethrel treatments did not affect lycopene content of examined varieties significantly. The quality of tomato products are characterised by their lycopene content. Colour is highly important quality factor of food products. The range in lycopene contents from all samples evaluated was 48.7 to 113.0 mg kg-1 fresh weight. Also correlations between lycopene content and colour (a*/b*, and chroma) were investigated also.

Toxicidade do níquel em plantas de feijão e efeitos sobre a microbiota do solo

O objetivo deste trabalho foi avaliar o efeito da adição de Ni ao solo (0, 2,3, 10,5, 47 e 210 mg kg-1), na presença e ausência de calcário, sobre: o desenvolvimento do feijoeiro; a fitodisponibilidade de Ni e algumas características biológicas do solo. O experimento foi conduzido em casa de vegetação, em Latossolo Vermelho distrófico. A dose de Ni de 210 mg kg-1 causou a morte de todas as plantas, tanto na presença como na ausência de calcário. Houve aumento da produção de grãos de feijão no tratamento que recebeu calcário. A concentração de Ni dos grãos aumentou com o incremento de Ni no solo, ultrapassando o limite máximo permitido, de 5 mg kg-1 de matéria fresca, na dose de 2,3 mg kg-1, indicando que a aplicação de calcário não foi suficiente para reduzir os teores de Ni no grão de feijão a níveis apropriados para o consumo. Observou-se diminuição da biomassa microbiana do solo nos tratamentos com altas concentrações de Ni, que foi acompanhada por aumento no qCO2. O qCO2 foi um indicador adequado do grau de estresse que teve a comunidade microbiana do solo com a adição de Ni.

Allelopathic Potential of Citrus junos Leaves and Abscisic Acid-Glucose Ester

The allelopathic potential of an aqueous methanol extract of Citrus junos leaves was investigated under laboratory conditions. The extract inhibited the growth of roots and shoots of cress (Lepidium sativum L.), lettuce (Lactuca sativa L.) and alfalfa (Medicago sativa L.) seedlings. Significant reductions in the root and shoot growth were observed as the extract concentration increased. Since abscisic acid -β-D-glucopyranosyl ester (ABA-GE) was found to be a major inhibitor in fruit peel of C. junos, ABA-GE in C. junos leaves was determined and the concentration was 540 μg kg-1 fresh weight in the leaves harvested on September 26, 2002. These results suggest that C. junos leaves possess allelopathic activity and could work as a weed inhibiting agent, which should be investigated further in the field for practical application.

Total Quercetin Content in Onion: Survey of Cultivars Grown at Various Locations

Because of potential benefits on human health, the content of quercetin, the major flavonol found in onion (Allium cepa), could become a selection trait in breeding programs. Total flavonol concentration in onion was examined by spectrophotometric analysis at 374 nm in three long-day hybrid cultivars grown at three locations (Parma, Idaho; Grand Rapids, Mich; Elba, N.Y.), and in three shortday hybrid cultivars grown at one location in Georgia in three different fields. Mean total flavonol concentrations for long-day hybrids ranged from 176 to 232 mg·kg-1 (ppm) fresh weight and 110 to 173 mg·kg-1 fresh weight among short-day cultivars. No significant effect of location (state or field) was detected (P > 0.05). A significant (P > 0.05) cultivar by field interaction was detected in the short-day experiment, with the hybrid `Sweet Vidalia' showing significant differences among fields. Overall, our results suggest that quercetin content in onion, as expressed by the total flavonol content, does not vary depending on the growing origin, and therefore could be evaluated effectively in breeding or commercial material.

Changes of anthocyanins and hydroxycinnamic acids affecting the skin colour during maturation of sweet cherries ( Prunus avium L.)

The content and relative amounts of anthocyanins and hydroxycinnamic acids (HCA) were determined in local sweet cherries (cultivar Petrovka) at 7 stages of maturity, by means of high performance liquid chromatography (HPLC), and compared to instrumentally assessed skin colour of the same sweet cherries. Skin colour of harvested samples was measured using the CIE L *, a *, b * system. The contents of neochlorogenic and 3′- p-coumarylquinnic acids decreased with no significant change in ratio during ripening, except for the first 4 days of maturation, when the ratio changed due to increased content of neochlorogenic acid. The linear increase of total anthocyanins during maturation was observed without the trend of stabilization in the final stages of maturity. The colour change of Petrovka during maturation was influenced by the increase of total anthocyanins, consisting mostly of cyanidin-3-rutinoside and cyanidin-3-glucoside (97–98% of the total). The chroma and L * values appeared to be optimal indicators of anthocyanin accumulation during maturation, and better than the a * value and hue angle. The accumulation of anthocyanins from 507.1 to 1150.9 mg of cyanidin-3-rutinoside/kg of fresh weight (FW) during the second half of maturation caused the formation of a new colour cast of Petrovka, which influenced the decrease of redness and colour intensity, as recognized by CIE L *, a *, b * colour space.