Acid In Strawberries Research Articles

Differences in analytical methods affect the analytical values of soluble solids, free sugar, and organic acid content of strawberries

The present study compares different pre-treatments used to analyze free sugars and organic acids in strawberries. Soluble solid content, free sugars, and organic acid content in strawberries may vary depending on the pre-treatment methods used for analyze. A comparison of freshly squeezed juice and that obtained post freezing and thawing revealed a significant reduction in sucrose content in the once-frozen juice. However, no significant differences were observed in the soluble solids, glucose, and fructose contents. Furthermore, crushed flesh had significantly higher soluble solid, glucose, and fructose levels and lower sucrose content than those of the juice. Crushed flesh exhibited significantly higher citric acid and a lower malic acid content than those in the juice. There was a significant reduction in sucrose content in the freeze-dried samples compared to all other pre-treatments. Contrastingly, citric and malic acid levels were higher in the freeze-dried samples than that in the freshly crushed samples. The sucrose analytical values can be greatly decrease during the pre-treatment process. Therefore, differences in analytical methods should be considered when comparing sucrose content and composition.

Comparative transcriptomic screen identifies expression of key genes involved in pattern-triggered immunity induced by salicylic acid in strawberry

Comparative transcriptomic screen identifies expression of key genes involved in pattern-triggered immunity induced by salicylic acid in strawberry

Pengaruh Penggunaan Madu Kaliandra (Calliandra callothyrsus) Kombinasi Ekstrak Buah Stroberi (Fragaria x ananassa) Konsentrasi 100% sebagai Bahan Alternatif untuk Pemutihan Gigi Secara in Vitro

Tooth discoloration can be overcome by doing bleaching treatment. Bleaching is an act of using chemicals that can whiten teeth using peroxide. The method that can be used is the home bleaching technique or in office bleaching. The use of teeth whitening agents can cause side effects, namely on the mucosa and sensitivity of the teeth so that natural teeth whitening ingredients are needed using calliandra honey and strawberries. The elegat acid and malic acid in strawberries will undergo oxidation where these two acids can bind to substances that can cause discoloration of the enamel. This type of research is an experimental laboratory in vitro. The sample in this study amounted to 32 samples of teeth. The first treatment was soaked in calliandra honey, a combination of strawberry fruit extract with a concentration of 100% and the second treatment group was soaked in distilled water. Immersion was carried out for 14 days with 3 hours of immersion in the morning and 3 hours at night. Taking the number of samples using the Frederer's formula. The results of this study saw the effect of significant color changes before and after immersion using Calliandra honey in combination with 100% concentration of strawberry fruit extract.

CONTENT AND COMPOSITION OF SUGARS AND ORGANIC ACIDS IN STRAWBERRIES, GROWN IN THE RIGHT-BANK FOREST- STEPPE ZONE OF UKRAINE

Garden strawberry is a valuable berry crop in Ukraine, the harmonious taste of its berries depends on the ratio of sugars and organic acids. Among the factors affecting the quantitative and qualitative composition of sugars and organic acids in berries, the area of cultivation and the pomological variety are distinguished. The article presents the results of studies of strawberry berries of Dukat, Honey and Polka varieties grown in the Right-Bank Forest-Steppe zone of Ukraine for the content and composition of sugars and organic acids using the methods of high-performance liquid chromatography on an Agilent Technologies chromatograph (model 1100) using a carbohydrate chromatographic column size 7,8×300 mm, "Supelcogel-C610H". It was found that the sugar content in strawberry berries of the Dukat, Honey and Polka varieties during the research period ranged from 5.0 to 8.6%. Berries of the Honey variety were distinguished by a significantly higher level of sugars – 8.6%. The content of reducing sugars in berries, according to the average data, was 4.9-7.7%. Among the investigated varieties, Polka berries had the lowest minimum amount of reducing sugars – 3.2%. The mass fraction of fructose was 2.1-4.4%, which is 42.0-51.1% of the sum of sugars, while glucose was 1.1-3.5% (22.0-40.7%) for a small amount of sucrose - 0.3-1.3, which is 6.0-15.1% of the total sugar content in berries. According to the results of the dispersion analysis, no significant influence of the pomological variety of berries on the content of reducing sugars was found. The mass fraction of organic acids in the berries of three strawberry varieties during the research period fluctuated within the limits 0.9-1.4% and significantly depended on the pomological variety of berries. The maximum amount of organic acids was found in Dukat berries - 1.4%. Organic acids in strawberries are represented by citric and malic acids with the dominance of citric acid – 57.0-68.1% of the total acid content. A higher level of citric acid was noted in strawberry berries of the Honey variety, while berries of the Ducat variety were distinguished by the level of apple acid. The sugar-acid index in all studied varieties of strawberry exceeded the value of 5.3, which made it possible to determine the taste of the berries as sweet and sour. In berries of the Dukat variety, it was lower due to the high content of organic acids.

Profiles of Sugar and Organic Acid of Fruit Juices: A Comparative Study and Implication for Authentication

A comparison of sugar and organic acid profiles among different fruit juices (including apple, pear, peach, grape, sweet cherry, strawberry, and blueberry with various varieties) was performed to assess the possibility for authentication coupled with chemometrics. It was found that the distribution of each sugar and organic acid in juices showed some specific characteristics related to fruit species, despite the fact that great differences in the content existed among different varieties. Sucrose was the most abundant sugar in peach juice, accounting for 58.26–77.11% of the total sugar content. However, in grape, blueberry, and sweet cherry juice, glucose and fructose were the predominant sugars. Pear juice contained the highest level of sorbitol, which contributed to 15.02–43.07% of the total sugar content. Tartaric acid was detected only in grape juice among the seven species of fruit juice, with a proportion of 57.95–89.68% in the total acid content. Malic acid was the predominant organic acid in apple and sweet cherry juice, accounting for 69.92–88.30% and 97.51–98.73% of the total acid content of each species. Citric acid was the predominant organic acid in strawberry and blueberry juice, which contributed to 62.39–83.73% and 73.36–89.56% of the total acid content of each species. With the aid of principal component analysis and linear discriminant analysis (LDA), the juice samples could be successfully classified according to fruit species by using the sugar and/or organic acid composition as analytical data. Combination of sugar and organic acid composition gave the best differentiation of these seven species of juices, with a 100% correct classification rate for both the original and the cross-validation method in LDA. Adding malic/citric into the dataset of the organic acid content may also improve the differentiation effect. Furthermore, the adulteration of sweet cherry juice, blueberry juice, raspberry juice, and grape juice with apple juice, pear juice, or peach juice could also be distinguished from their corresponding pure juices based on sugar and organic acid composition by LDA.

Effectiveness of Strawberry Extract with 100% Concentration in Cleaning Teeth with Extrinsic Stain at the Academic Community of Poltekkes Kemenkes Jakarta I

Discoloration of teeth can be caused by stains on the surface of the teeth or due to changes in tooth material. Tooth stain can be extrinsic, intrinsic, or age-related. Tooth whitening (bleaching) can be done in the office and at home. Strawberry is a fruit with many benefits, one of which is whitening teeth. The content of malic acid and ellagic acid in strawberries has the effect of tooth whitening. The purpose of this study was to determine the effectiveness of strawberry extract with a concentration of 100% in cleaning teeth with the extrinsic stain on an academic member of the Health Polytechnic Jakarta I. This study was an experiment on 31 people who had upper and lower anterior teeth with the extrinsic stain as samples. Data collection was done by applying strawberry extract with a concentration of 100% on the surface of the anterior teeth, allowed to stand for 5 minutes, then brushed and rinsed with water. This procedure was done 2 times a day for 5 consecutive days. Changes in extrinsic stain were measured using the Lobene Stain Index which measures the intensity and area of the stain, as well as a combined score of both. The average combined score with measurements using the Lobene Stain Index for extrinsic stain before being treated with strawberries was 22.4. The score has decreased every day starting from day 1 to day 5 of treatment. The largest decrease of the average Combined Score was occurred on the 2nd day, namely from a score of 20.0 on the 1st day to 14.6 on the 2nd day with a percentage reduction of 35.0%. Statistical tests showed significant results of 0,000 reducing the Intensity Score and Area Score on day 2 to day 5. It can be concluded that there was a significant decrease in extrinsic stain scores after treatment on day 2. 
 
 Keywords: extrinsic stain; strawberry extract

Optimization and validation of a method based on QuEChERS extraction and liquid chromatographic–tandem mass spectrometric analysis for the determination of perfluoroalkyl acids in strawberry and olive fruits, as model crops with different matrix characteristics

A QuEChERS method was optimized and validated for the LC–MS/MS analysis of perfluoro-n-pentanoic acid (PFPeA), perfluoro-1-butanesulfonic acid (PFBuS), perfluoro-n-hexanoic acid (PFHxA), perfluoro-n-heptanoic acid (PFHpA), perfluoro-1-hexanesulfonic acid (PFHxS), perfluoro-n-octanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA), perfluoro-1-octanesulfonic acid (PFOS) and perfluoro-n-decanoic acid (PFDA) in freeze-dried strawberry and olive, as model fruits characterized by very different chemical compositions. The method was evaluated for apparent recovery, intra-day and inter-day precision, matrix effect and recovery. The method optimized for strawberry provided for most compounds absolute values of matrix effect (|ME%|) ≤ 11%, except for PFHxA, which showed a signal suppression of 22%. The extraction efficiency was tested at the spike levels 500–5000 pg/g d.w. for PFPeA, PFBuS, and PFHxA, and 100–1000 pg/g d.w. for the other target analytes, evidencing as a whole recoveries in the range of 65–89%. For olive fruits, due to their high fat content, an ultrasound-assisted extraction was necessary to obtain an efficient sample disgregation so as to increase the extraction yield and its precision. Moreover, a d-SPE clean-up with GCB allowed to achieve |ME%| ≤ 8% (except for PFBuS, which showed a signal enhancement of 19%) and recoveries calculated at the aforementioned spike levels were in the range 75–97%. The two methods provided very good linearity (R2 ≥ 0.9984) from 10,000 pg/g down to compound specific quantification limits, which were included in the ranges of 2.9–393 pg/g and 2.6–127 pg/g for strawberry and olive fruit, respectively. The methods were applied to the analysis of PFAAs in strawberry and olive fruits commercially available in two Italian supermarkets, as well as obtained under irrigation with various treated wastewaters (TWWs), evidencing in both cases a higher PFAAs occurrence in olives than in strawberry. However, PFAAs concentrations determined in the investigated fruit matrixes were quite low, being their sum 1.9 ng/g d.w. in the worst case (i.e. olive fruits grown under irrigation with TWWs).

The Effectiveness Differences Between Watermelon (Citrullus lanatus) Extract 100% and Carbamide Peroxide Gel 10% in Tooth Whitening (ex vivo)

Introduction: Discoloration can be caused by intrinsic or extrinsic factors. One of the discoloration treatments is teeth whitening. Teeth whitening process usually uses chemicals such as hydrogen peroxide or carbamide peroxide which can cause side effects, namely gingival irritation. Previous research has found that malic acid in strawberries can whiten teeth. Watermelons contain greater malic acid than strawberries. Objective: To analyze the effectiveness of 100% watermelon (Citrullus lanatus) extract on teeth whitening. Methods: The study was a laboratory experimental study with a total of 15 anterior post-extraction teeth which were discolored using black tea, divided into 3 groups. Group 1 was immersed in 100% watermelon extract, group 2 was immersed in 10% carbamide peroxide as positive control and group 3 was immersed in sterile aquades as negative control, for 56 hours, measured using a shade guide and spectrophotometer. Data were analyzed using one way Anova. Results: The 100% watermelon extract was effective for teeth whitening. There was a significant difference between 100% watermelon extract compared to negative control (p < 0.05). However, there was also a significant difference between 100% watermelon extract, and 10% carbamide peroxide gel (p = 0.003). Conclusion: The watermelon extract has the ability as teeth whitening agent. However, further study is still needed to explore this result and determine the proper concentration for teeth whitening.

ORGANİK OLARAK YETİŞTİRİLEN ÇİLEK VE YABANMERSİNİ MEYVELERİNİN FENOLİK BİLEŞEMİNİN İNCELENMESİ

The present study aimed to investigate phenolic compounds of strawberry which is organically-grown in Bursa region and blueberry in Trabzon region. The phenolic acids and flavonoids were detected by RP-HPLC according to their retention times with the help of diode array detector at 280 nm, 320 nm and 360 nm. Investigated compounds were gallic acid, epigallocatechin, catechin, epicatechin, epicatechin gallate, 2 coumaric acid, 3 coumaric acid, 4 coumaric acid, chlorogenic acid, cafeic acid, neochlorogenic acid, trans resveratrol, ferulic acid, quercetin, kaempferol and myricetin. According to results it was determined that bluberry fruit contains high amounts of chlorogenic acid (644.25 mg/kg) and among the phenolic acids in strawberries, 4 coumaric acid is regarded as major phenolic compound (3.76 mg/kg). The highest level of myricetin compounds was measured in blueberry (14.41 mg/kg), on the contrary, myricetin was not identified in strawberry fruits but this fruit is especially rich in catechins (58.34 mg/kg).

Change of the main components of a chemical composition of frozen strawberries under previous treatment in solutions with structure-retaining properties

The objective of the research lies in the study of the main indices of the chemical composition of strawberries during freezing and storage under its previous treatment in solutions with structure-retaining properties. The main indices of the chemical composition of strawberries during freezing and a six-month storage under previous treatment in the solutions with structure- retaining properties were studied, namely in 1 %, 2 % and 3 % solutions of potato starch and 1 % and 2 % sugar-pectin solution.The main components of the chemical composition were identified. The content of soluble solids was determined using refractometer, sugar content was measured by means of ferricyanide method, organic acids were identified by alkali titration, ascorbic acid content was determined by iodometric method.It has been found that during freezing and storage of frozen strawberries there are losses of the main components of chemical composition, the amount of which considerably depends on the type and concentration of the solution for treatment.Application of the previous treatment of strawberries before freezing helps to retain the main components of chemical composition of strawberries during freezing and storage. Losses of soluble solids of previously treated strawberries during freezing were by 0,9 – 1,2 % lower compared to control. Sugar content went down to1,8 – 3,3 % as the result of freezing. Previous treatment of berries before freezing promotes their preservation by 0,1-0,7 %. Organic acids content in strawberries remained practically unchanged. Ascorbic acid content during freezing of strawberries suffered essential losses that made up 43,8 – 50,3 % under the lowest in the sample that were previously treated in 2 % sugar-pectin solution and by 13 % lower than in control. During storage the losses of ascorbic acid in strawberries without previous treatment were by 4,4 – 7,6 % higher

Ellagic acid in strawberry (Fragaria spp.): Biological, technological, stability, and human health aspects

Ellagic acid in strawberry (Fragaria spp.): Biological, technological, stability, and human health aspects

Formation of β-glucogallin, the precursor of ellagic acid in strawberry and raspberry.

Ellagic acid/ellagitannins are plant polyphenolic antioxidants that are synthesized from gallic acid and have been associated with a reduced risk of cancer and cardiovascular diseases. Here, we report the identification and characterization of five glycosyltransferases (GTs) from two genera of the Rosaceae family (Fragaria and Rubus; F. × ananassa FaGT2*, FaGT2, FaGT5, F. vesca FvGT2, and R. idaeus RiGT2) that catalyze the formation of 1-O-galloyl-β-D-glucopyranose (β-glucogallin) the precursor of ellagitannin biosynthesis. The enzymes showed substrate promiscuity as they formed glucose esters of a variety of (hydroxyl)benzoic and (hydroxyl)cinnamic acids. Determination of kinetic values and site-directed mutagenesis revealed amino acids that affected substrate preference and catalytic activity. Green immature strawberry fruits were identified as the main source of gallic acid, β-glucogallin, and ellagic acid in accordance with the highest GT2 gene expression levels. Injection of isotopically labeled gallic acid into green fruits of stable transgenic antisense FaGT2 strawberry plants clearly confirmed the in planta function. Our results indicate that GT2 enzymes might contribute to the production of ellagic acid/ellagitannins in strawberry and raspberry, and are useful to develop strawberry fruit with additional health benefits and for the biotechnological production of bioactive polyphenols.

Polyphenols in strawberry (Fragaria × ananassa) leaves induced by plant activators.

Strawberry leaves contain high amounts of diverse phenolic compounds potentially possessing defensive activities against microbial pathogens and beneficial properties for human health. In this work, young strawberry plants were treated with two plant activators, S-methylbenzo-1,2,3-thaidiazole-7-carbothiate (BTH) and birch wood distillate. Phenolic compounds from activator-treated and control leaves were subjected to quantitative analyses by HPLC-DAD, HPLC-ESI-MS, and microQTOF ESI-MS. Thirty-two different phenolic compounds were detected and characterized, and 21 different ellagitannins constituted the largest group of compounds in the strawberry leaves (37.88-45.82 mg/g dry weight, 47.0-54.3% of total phenolics). Treatment with BTH resulted in higher levels of individual ellagitannins, whereas treatment with birch wood distillate strongly increased the levels of chlorogenic acid in strawberry leaves compared with the control. The results suggest that different plant activators may be useful tools for the activation of different branches in the phenylpropanoid biosynthesis in strawberry.

Determination of Ellagic Acid in Strawberries, Raspberries and Blackberries by Square-Wave Voltammetry

Determination of Ellagic Acid in Strawberries, Raspberries and Blackberries by Square-Wave Voltammetry

NEW MARKERS FOR THE TRACEABILITY OF ORGANIC FRUIT

The objective of the present research was to define a traceability system for organic fruits (orange, peach and strawberry) to monitor the classical parameters of quality (carpometric characteristics, total soluble solids (TSS), total acidity (TA), and ascorbic acid). We also aimed to monitor the parameters of several plant metabolites, such as synephrine in orange juice, ellagic acid in strawberries, and phenolic and volatile compounds in peaches, whose biosynthesis could be influenced by the use of an organic or conventional cultivation system. In addition, taking into account several specific aspects of the two cultivation methods, such as the different kinds of nitrogen soil fertilization used, a study was carried out to verify the possibility to differentiate between organically and conventionally grown fruit through the detection of markers linked to nitrogen metabolism. The ratio of stable isotopes of nitrogen 15 N/ 14 N in the proteins of pulp (δ 15 N PP) of different fruit species was determined. Our results showed that the cultivation method did not determine relevant differences in the quality parameters in oranges and peaches, whereas in strawberries, differences between organic and conventional fruits were observed. The ascorbic acid content in the three species studied was always higher in the organic fruits. Moreover, the level of bioactive compounds, such as skin anthocyanins in the 'Spring Lady' peach cultivar, was higher in the organically grown fruits. Peaches and oranges from organically managed farms had statistically higher δ 15 N PP values compared with the conventional ones. Therefore, the application of organic fertilizers, which notoriously increase the level of δ 15 N in the soil, also leads to an increase of δ 15 N values in the organic fruit. For that reason, this parameter can be used as a new marker to differentiate organically from conventionally grown fruit. Regarding the δ 15 N level found in strawberry pulp, no difference was observed between organic and conventional fruits because organic fertilizers are often employed even in conventional systems.

Polarographic (DCP & DPP) Determination of Ellagic Acid in Strawberries & Pharmaceutical Formulations

AbstractDirect Current (DC) and Differential Pulse (DP) Polarographic methods have been developed for the qualitative as well as quantitative analysis of ellagic acid in plant products (i.e. strawberries) and pharmaceutical formulations (Ellagic insurance formula). Ellagic acid produces a well‐defined polarographic wave/peak in pyridine hydrochloride at pH 6.8 ± 0.1 with E1/2 /Ep = −1.298 V vs. SCE.The wave/peak height is found to be proportional to the concentration of ellagic acid. The developed procedure was used for the analysis of ellagic acid in an extract of strawberries (Fragaria × ananassa) and pharmaceutical formulations. Statistical treatment of the observed polarographic data revealed high accuracy and good precision of determination.The work has been supplemented by FTIR screening of the sample. The percentage of ellagic acid in pharmaceutical formulations was determined by the developed method, which is in close agreement with the labeled amount.

Bioactive compounds and quantification of total ellagic acid in strawberries ( Fragaria x ananassa Duch.)

Strawberries are one of the most popular edible fruits in Brazil and their consumption has increased with the development of new varieties available at almost all seasons. Fruit of seven full-ripened strawberry cultivars (Dover, Camp Dover, Camarosa, Sweet Charlie, Toyonoka, Oso Grande and Piedade) were characterized in relation to the total phenolics, vitamin C, flavonoids, free and total ellagic acid contents and antioxidant capacity. Camp Dover had the lowest values for anthocyanins and total phenolics but the highest total flavonoid content. Dover presented the highest anthocyanin, total phenolics and ellagic acid contents and also elevated antioxidant capacity. The best conditions for the determination of the total ellagic acid content in strawberries were also optimized and the results showed that the extraction with 80% acetone, and hydrolysis using 2 N TFA at 120 °C for 60 min allowed a 99% recovery.

Effects of genotype and environment on total anti-oxidant capacity and the content of sugars and acids in strawberries (Fragaria × ananassa Duch.)

SummaryTotal anti-oxidant capacity (TAC) and the contents of mono- and disaccharides, and organic acids were determined in strawberry fruit from ten genotypes sampled from eight experimental sites in Norway in 2002 and 2003. The difference between genotypes was significant for all recorded traits, and it appeared possible to select for all traits in breeding programmes. On average, the Norwegian bred cultivar ‘Carmen’ had a TAC of 30.07 mmol kg–1 fresh weight (FW), compared to 23.16 mmol kg–1 FW in the standard cultivar ‘Korona’. TAC was negatively correlated with fruit size, rainfall and leaf surface humidity, but was positively correlated with the minimum temperature on the day prior to sampling. Mono- and di-saccharide contents were negatively correlated with both minimum and maximum temperatures, and with wind velocity. It was confirmed that the sugars:organic acids ratio was inversely related to the maximum temperature on the day before harvest, which supports anecdotal claims that strawberries grown in northern areas have, on average, better flavour.

Ellagic acid content in strawberries of different cultivars and ripening stages

AbstractEllagic acid is a phenolic compound which occurs naturally in strawberries. Interest in ellagic acid has increased during the past few years owing to its properties as a micronutrient. The objective of this study was to determine the ellagic acid content in strawberries compared with that in other common fruits and to evaluate its variability, the effects of ripening stage, and the tissue and seasonal variability in selected cultivars widely grown in Argentina. Strawberries showed significantly higher levels of ellagic acid than many other fruits of economic importance, ranging from 0.16 to 2.07 mg g−1 dry weight. The ellagic acid content was highest in green fruit, intermediate in mid‐ripe fruit and lowest in full‐ripe fruit. Cultivars ‘Chandler’ and ‘Camarosa’ contained the highest amounts of ellagic acid in strawberries with edible value (0.78 and 0.70 mg g−1 dry weight respectively), while ‘Oso Grande’ and ‘Milsei’ exhibited the lowest (0.35 and 0.31 mg g−1 dry weight respectively). Moreover, the level of this phytochemical was found to be higher when considering pulp with achenes compared with pulp without achenes. Copyright © 2003 Society of Chemical Industry

Prediction of chromatographic retention, p Ka values and optimization of the separation of polyphenolic acids in strawberries

Polyphenolic acids are a complex group of compounds that have attracted enormous attention in the last few years because of their biological properties. In this work, the proportion of organic modifier and the pH of acetonitrile–water mixtures used as mobile phases were optimized in order to separate a series of polyphenolic compounds. The linear solvation energy relationship formalism based on the single solvent polarity parameter, E N T , was used to predict their chromatographic behavior as a function of the percentage of acetonitrile in the eluent. Moreover, the correlation established between retention and the pH of the aqueous–organic mobile phase was used to optimize the pH of the mobile phase. The optimized mobile phase is composed of acetonitrile and formic acid buffer adjusted to pH 4.25, with 12% (v/v) acetonitrile. Also, the p K a values of polyphenolic acids in acetonitrile–water mixtures were determined using chromatographic data, and in order to validate the optimized conditions, a series of polyphenolic compounds was studied in strawberries.