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Comparative study of bioactive components in
pear genotypes from Ardahan/Turkey
Zehra Tuğba Abacı, Emre Sevindik & Muavviz Ayvaz
To cite this article: Zehra Tuğba Abacı, Emre Sevindik & Muavviz Ayvaz (2016) Comparative study of bioactive components in pear genotypes from Ardahan/Turkey, Biotechnology & Biotechnological Equipment, 30:1, 36-43, DOI: 10.1080/13102818.2015.1095654 To link to this article: https://doi.org/10.1080/13102818.2015.1095654
© 2015 The Author(s). Published by Taylor & Francis.
Published online: 14 Oct 2015.
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ARTICLE; AGRICULTURE AND ENVIRONMENTAL BIOTECHNOLOGY
Comparative study of bioactive components in pear genotypes from Ardahan/
Turkey
Zehra Tugba Abacıa, Emre Sevindikband Muavviz Ayvaz b
aFood Engineering Department, Ardahan University, Ardahan, Turkey;bDepartment of Agricultural Biotechnology, Adnan Menderes University, Aydın, Turkey
ARTICLE HISTORY
Received 15 June 2015 Accepted 15 September 2015
ABSTRACT
In this study, 10 pear genotypes (_Incir, Bal, Nene, Kabak, Banda, Kırmızı, _Imlahor, Baraka, Limon and G€ug€um), which grow in the Ardahan region, were evaluated for their total phenolic content, total anthocyanin content, brix, pH, titratable acidity, total ascorbic acid content and antioxidant activity. According to the results, the pear genotypes used in this study had a high brix8 content, high phenolic, anthocyanin and ascorbic acid contents, as well as high antioxidant activity. It was determined that‘Bal’ pear had the highest total phenolic content and antioxidant activity. In ‘Nene’ and‘Incir’ pears, the quantity of ascorbic acid and anthocyanin, as well as the antioxidant activity were less than those in the other genotypes. Correlations between brixand pH, acidity and pH, peel phenolic content andflesh phenolic content, flesh ascorbic acid content and peel phenolic content, peel antioxidant activity andflesh phenolic content, were found to be significant. As a conclusion, due to the high levels of antioxidants and other bioactive compounds in pears, it is suggested to consume those fruits, especially with their peels. The results from this study will provide new insights into farming, fresh fruit consumption, industrial food processing and future research studies.
KEYWORDS
Pear; antioxidant; phenolic; ascorbic acid; anthocyanin
Introduct
ıon
Pear is an important type of fruit, which is grown in Tor-rid Zones.[1] China is in the first place of pear farming with its 60% share of the pear production in the world. [2] According to 2012 data, Turkey’s annual pear
produc-tion is 387,345 tons.[3] Pear, which is native to Anatolia, Caucasia and Central Asia, has nearly 600 types in our country. In Ardahan region, 38 tons of pears are pro-duced annually in a 34 daa area. However, this amount of pear production provides limited economic profit to farmers compared to other agricultural products in the region.
Fruits, like pear, are important nutritions as carbo-hydrate sources. They contain approximately 54% fructose, 18% sorbitol, 15% sucrose, 13% glucose, low protein (0.5%) and lipid (0.3%) contents and high
inci-dence of fibre (15 28 g/kg). These rates are suitable
for diabetic and obese patients.[4,5] Pear contains
more fibre than many other fruits.[6] In addition to
the high level of carbohydrate and fibre, it contains
other important nutritional elements, such as vita-mins, minerals, anthocyanins and phenolic contents.
[7] Phenolic compounds have a significant importance
in the resistance to mechanical and biological stress. They also have a great importance due to the presence of pharmacological characteristics and factors which reveal the quality of the fruit, such as flavour, colour,
soreness and acidity.[8] Other previously performed
studies showed that fruit consumption reduces the risk of chronic diseases such as cancer and diabetes, as well as cardiovascular and nerve diseases.[9 12] It is stated that the antioxidant effect of phenolic compounds within fruits and vegetables reduces the disease risk. [13] Therefore, consumption of nourishments contain-ing phenolic compounds is essential.[14]
In the human body, free radicals, such as H2O2, can
occur due to various reasons.[15] Free radicals may occur because of two reasons: internal sources, such as ageing and nutrition metabolism, and external sources, such as air pollution.[16,17] It is known that these free radicals can be inactivated by phenolic compounds with antioxi-dant activity, such as ascorbic acid, vitamin E, carote-noids and anthocyanins.[18] Another antioxidant, which is nonenzymatic, is ascorbic acid and it has a great importance in the detoxification of reactive oxygen spe-cies.[19] It is seen that in pear tissues, in which oxidative
CONTACT Muavviz Ayvaz [email protected]
© 2015 The Author(s). Published by Taylor & Francis.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
harm occurs, browning is seen due to the presence of ascorbic acid destruction.[20,21] Ascorbic acid partici-pates in the prevention of plant diseases, browning and decay of the fruits.[22,23] The aim of the present study
was tofind out the nutritional value and to determine
the bioactive compounds in pear genotypes growing in the Ardahan region.
Materials and methods
Fruit samples
Fruit samples of 10 genotypes (_Incir, Bal, Nene, Kabak, Banda, Kırmızı, _Imlahor, Baraka, Limon and G€ug€um) were harvested at optimum maturity periods (at the begin-ning of the fourth week of September) from the Ardahan region (Figure 1). The samples were stored at 4C in a refrigerator. In every genotype, brix, pH, titratable acid-ity, total phenolic, total anthocyanin and ascorbic acid contents, as well as total antioxidant activity, were ana-lysed. The productivity was also determined. Sensory evaluations on fruit aroma, colour of theflesh and peels were carried out. The measurements were performed in triplicate.
Fruit weight, brix, pH and titratable acidity
For each genotype, the weight of 10 fruits was measured in grams (g). Fruit samples were scaled on digital scales
with an accuracy of 0.05 g. Brixof fruits was determined at 22C with Mettler Toledo 30 P digital refractometer (Mettler-Toledo International Inc., Switzerland) in percen-tages (%). The acidity percenpercen-tages were determined by using a titrimetric method according to Cemeroglu.[24] Purified water (90 mL) was added to 10 mL fruit juice, and it was titrated with 0.1 mol/L sodium hydroxide (NaOH) until the pH level reached 8.1. The obtained titratable acidity was calculated in terms of malic acid in percentages (%).
Total anthocyanin, total phenolic and ascorbic acid contents
Determination of total anthocyanin content of the fruit peel was made by using the method, described by Giusti and Wrolstad.[25] Fruit peel (5 g) was homogenized in 10 mL methanol solution containing 1% (v/v) HCl for two minutes. After keeping for a night, it was filtered
with Whatman No. 2filter paper. The samples’
absorp-tion was measured by using a spectrophotometer (Unico S1205) at a wavelength of 530 nm. The anthocyanin con-tent was measured by using molar absorptivity of cya-nide-3-glucoside. Results were expressed as milligrams of total anthocyanin per 100 grams of fruit peel sample (mg/100 g).
The total phenolic compound content of the fruit peel
and flesh was determined by using Folin Ciocalteu
method.[26] After 14 g of fruit sample (separately for
Figure 1.Location of the Ardahan region.
Map data: US Dept of State Geographer © 2015 Google © 2015 Basarsoft Image Landsat.
fruit peel and fruitflesh) was homogenized with 40 mL ethanol, it was centrifuged at 6000g for 3 min.
Folin Ciocalteu reagent with a quantity of 1000 mL
(1/10 diluted) and 800mL (7.5%) Na2CO3were added to
200 mL supernatant. After incubating for 2 h at room
temperature, the mixture was measured at 750 nm in a spectrophotometer against 50% ethanol water mixture. The total amount of samples’ phenolic compound was measured by using gallic acid standard. The results were expressed as milligrams of total phenolic content per 100 grams of fruit peel orflesh sample (mg/100 g).
Determination of the ascorbic acid content was made by using a spectrophotometric method.[27] Fruit sample (5 g) was homogenized in 50 mL purified water and
cen-trifuged at 4000g for 5 min. Supernatant (100mL) was
obtained and mixed with 400 mL 0.4% (v/v) oxalic acid
and 4.5 mL 2,6-dichlorophenolindophenol solution, and then measured at a wavelength of 520 nm in a spectro-photometer. The amount of ascorbic acid in fruits was measured by using a calibration chart. Results were expressed as milligrams of ascorbic acid content per 100 grams of fruitflesh sample (mg/100 g).
Antioxidant activity
The antioxidant activity of the fruit peel andflesh was determined according to 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging factor. Tissue sample (2 g) was homogenized by mixing with 2 mL extraction solution (85% methanol, 15% acetic acid) and incubated for 24 h at 4 C. After this, it was centrifuged at 11,952g for
10 min. DPPH solution (950 mL, 0.1 mol/L) was mixed
with 50mL extract, diluted separately from the fruit flesh and peel. The solution was left for 30 min in a shaker at room temperature in the dark. Afterwards, samples were measured at a standard wavelength of 515 nm with a spectrophotometer. For each sample, fruitflesh and peel were measured separately. The antioxidant activity was measured with the following equation: %DPPH radical
scavenging D (Absorbancecontrol Absorbancesample)/
Absorbancecontrol£ 100.[28,29] The control was
contain-ing all reagents without the sample.
Data analyses
In this study, all analyses were performed in triplicate, and during the evaluation of the obtained data, SPSS 15.0 statistical analysis packaged software was used. Dif-ferences among groups were determined with Duncan’s multiple comparison tests and were considered signifi-cant at p< 0.05. Analysis of relationships between varia-bles was carried out using Pearson’s correlation test on data sets. Cluster analyses were applied for determina-tion of the distance between genotypes.
Results and discussion
Ten different pear genotypes were detected in Ardahan.
It was determined that one of the genotypes, ‘Banda’
pear, belonged to Pyrus salicifolia, whereas the other genotypes belonged to Pyrus communis species. Fruit weight, brix, pH, degree of acidity and some pomologi-cal features of the genotypes are described inTable 1.
Table 1.Fruit weight, brix, pH, acidity and some pomological features of pear genotypes.
Genotype Locality Peel colour Flesh colour Aroma Harvested time _Incir pear Posof Green White Moderate 10.10.14
Bal pear Posof Yellow Cream Moderate 08.10.14
Nene pear ¸Cıldır Yellow Cream Moderate 13.10.14 Kabak pear Posof Light orange Cream Moderate 13.10.14 Banda pear ¸Cıldır Yellow green Cream Moderate 15.10.14 Kırmızı pear Posof Orange green Cream Strong 15.10.14 _Imlahor pear ¸Cıldır Green red Cream Faint 13.10.14 Baraka pear Posof Green brown Cream Faint 13.10.14 Limon pear Posof Yellow light red Cream Moderate 15.10.14 G€ug€um pear Posof Yellow brown Cream Moderate 08.10.14 Genotype Fruit weight (g) Brix(%) Acidity (%) pH Productivity _Incir pear 101.2 14§ 0.02b 0.25§ 0.16e 5.23§ 0.29ab Moderate Bal pear 57.3 16§ 0.12a 0.20§ 0.22e 5.50§ 0.56a High
Nene pear 102.0 14§ 0.32b 0.39§ 0.34c 5.10§ 0.07b Low Kabak pear 92.6 13§ 0.33c 0.42§ 0.04b 4.92§ 0.34c Moderate
Banda pear 53.0 14§ 0.11b 0.46
§ 0.60b 5.00
§ 0.23b High
Kırmızı pear 79.0 13§ 0.09c 0.30§ 0.43d 5.38§ 0.15a Moderate
_Imlahor pear 70.7 12§ 0.22d 0.24§ 0.56e 5.26§ 0.06ab Low
Baraka pear 127.3 14§ 0.07b 0.37§ 0.45c 5.04§ 0.15b Moderate
Limon pear 110.6 11§ 0.05e 0.59§ 0.05a 3.84§ 0.19d Moderate
G€ug€um pear 282.0 12§ 0.10d 0.56§ 0.42a 3.99§ 0.07d Low
Note: Data are presented as mean§ standard deviation (SD) and each value is the mean of three replicates. Different superscript letters within the columns indicate significant differences (p < 0.05).
Statistically significant differences among different geno-types of these parameters were found (p< 0.05).
The occurrence of fruit peel colour, such as green, yel-low and brown, is determined by factors like genetic, phenolic andflavonoid contents.[30] In the study, green, yellow and brown peel colours were observed. In some genotypes, red and orange marks were observed on the peel. It was indicated that the weight of the pear geno-types varied from 282 g (‘G€ug€um’ pear) to 53 g (‘Banda’ pear). According to a study conducted in Iran on 10 dif-ferent pear types, the weight of the fruit was the highest in‘Latanz’ type (171 g) and the lowest in ‘Arbakhoj’ type of pear (50.7 g).[29]
The amount of brixand acid in fruits is an indicator offlavour.[29] In our study, it was determined that ‘Bal’ pear had the highest amount of brix(16%) and‘Limon’ pear had the lowest amount of brix(11%). Correspond-ing to the results of brix, it was found that ‘Bal’ pear had the lowest amount of acidity (0.20%) and the
high-est pH value (5.50), and ‘Limon’ pear had the highest
amount of acidity (0.59%) and the lowest pH value (3.84). Similar results were obtained by different researchers. Tanrioven and Eksi [31] reported that brix contents of pear types vary from 8.4% to 13.6%. They also reported that‘Sugar’ type had the highest rate and ‘Starkrimson’ type had the lowest rate.[31] In a
previ-ously conducted study, it was found that ‘Latanz’ had
the highest brixrate (13.44%),‘Zizaling’ had the lowest
one (8.83%), ‘Arbakhoj’ had the highest acidity rate
(0.89%) and ‘Amrud’ had the lowest one (0.22%).[29]
Rahmatian et al. [32] reported that in ‘Faevrit Daglas’ type, the total acidity rate was 0.75% and in‘Shahmive’ type it was 0.18%. Chen et al. [33] found out that the acidity levels of ‘Jingbai’ and ‘Kuerle Fragrant’ were 0.46% and 0.10%, respectively.
It can be seen fromTable 2that pear genotypes con-tain anthocyanin, ascorbic acid and phenolic contents, as well as antioxidant compounds. Statistically significant
differences among different genotypes were found (p< 0.05). The phenolic content differs in accordance with the fruit maturity. It increases during the first three months of fruit development and then it starts to decrease. The amount of phenolic content in the fruit depends on the type and maturity degree. The phenolic content is higher in immature plants.[31] In the present study, it was determined that the amount of phenolic
content in peels was the highest in ‘Bal’ pear
(687.2 mg/100 g) and in‘Limon’ pear (650.3 mg/100 g),
and the lowest amount was in ‘Nene’ pear
(300.1 mg/100 g) and in ‘_Incir’ pear (342.3 mg/100 g). Correspondingly, it was found that the total phenolic content in the fruit flesh was the highest in ‘Bal’ pear
(300 mg/100 g) and in ‘Limon’ pear (230.5 mg/100 g)
and the lowest content was found in ‘Nene’ pear
(112.6 mg/100 g) and in ‘_Incir’ pear (115.9 mg/100 g). Results similar to ours were also discovered by other researchers.[31,34] Chong et al. [35] found out that the total phenolic content in the fruitflesh was 231.7 mg/ 100 g. In some pear peels grown in Iran, the total pheno-lic content was found to be between 261.13 and 135.17 mg/100 g.[29] The total phenolic content was the highest in‘Abkhoj’ and the lowest in ‘Khoj Babaei’. It was reported that the total phenolic content in fruit flesh was between 10.06 and 30.11 mg/100 g. The highest phenolic content was reported in‘Khoj Babaei’ and the lowest one was reported in‘Arbakhoj’.[29] It was found that in‘Nakh’ and ‘Naspati’ pear types, the total phenolic content of the fruit peel was between 601 and 619 mg/
100 g, and that of the fruitflesh was between 333 and
355 mg/100 g.[36] The amount of the phenolic content in plant tissues is affected by environmental conditions, such as ultraviolet light, heat and nutrition.[37 40] Because pear fruits have phenolic contents, they are strong antioxidant sources and have medical features; tumours, inflammations and most of the allergic diseases can be prevented by them.[41,42]
Table 2.Antioxidant activity and anthocyanin, ascorbic acid and total phenolic contents of pear genotypes.
Genotype Total phenolic content (P) (mg/100 g) Total phenolic content (F) (mg/100 g) Ascorbic acid content (F) (mg/100 g) Antioxidant activity (P) (%) Antioxidant activity (F) (%) Total anthocyanin content (P) (mg/100 g) _Incir pear 342.3§ 0.30 115.9§ 1.6c 4.4§ 0.76d 20.2§ 0.71e 25.6§ 0.02f 1.4§ 0.02e Bal pear 687.2§ 0.93 300§ 0.99e 9.2 § 0.92ab 65.3 § 0.23a 55.4 § 0.95a 2.3 § 0.00d Nene pear 300.1§ 1.20 112.6§ 1.2cd 6.6§ 0.45cd 43.4§ 0.45d 30.6§ 1.32e 5.8§ 0.23c Kabak pear 655.8§ 0.92 220.1§ 1.3a 10§ 0.67ab 32.6§ 0.62de 42.3§ 1.00c 4.2§ 0.32cd Banda pear 432§ 0.56 203.2§ 1.0b 10.2§ 0.70a 46.1§ 0.07c 44.2§ 0.98bc 9.5§ 0.10bc Kırmızı pear 500.3§ 0.02 216.8§ 0.89ab 7.6§ 0.17c 52.8§ 0.09bc 50§ 0.56b 20.2§ 0.12a _Imlahor pear 567§ 1.00 222§ 0.04ab 6.2§ 1.30cd 55.6§ 0.15b 51.9§ 0.72b 4.4§ 0.05cd Baraka pear 360.1§ 0.87 147§ 0.05d 6.5§ 1.00cd 32.1§ 0.10de 46.2§ 0.65bc 12.6§ 0.60b
Limon pear 650.3§ 0.89 230.5§ 0.12a 10.1§ 0.83a 56.7§ 0.01b 34.5§ 0.04d 4.7§ 0.23cd G€ug€um pear 455§ 0.99 201.1§ 0.56b 8.8§ 0.27b 49.9§ 0.34c 40.2§ 1.32c 2.5§ 0.12d
Note: Data are presented as mean§ SD and each value is the mean of three replicates. Different superscript letters within the columns indicate significant differences (p < 0.05). Fruit peel (P); fruitflesh (F).
Ascorbic acid, which is in abundance in plant cells, has many biological functions. As an antioxidant, it protects plants from oxidative harm derived from internal factors, such as respiration and photosynthesis metabolism, or from external factors, such as environmental pollution. [43] In the present study, it was identified that ascorbic
acid contents were the highest in ‘Banda’ pear
(10.2 mg/100 g) and in‘Limon’ pear (10.1 mg/100 g), and lowest in‘_Incir’ pear (4.4 mg/100 g). Like other biochemi-cal components, the ascorbic acid concentration in fruits differs, depending on the growth conditions, such as light and heat.[44,45] It was reported that ascorbic acid content in pear tissues after the harvest was 7.2 mg/ 100 g.[46] However, after a storage of 199 d in controlla-ble atmosphere conditions, it decreased to 2.3 mg/ 100 g.[46] Similarly, it was indicated that in six varieties of pears, the amount of ascorbic acid was between 2.6 and 5.3 mg/100 g.[47]
The red colour in pears originates from the presence of anthocyanin. Alongside the anthocyanin in fruits, there are also chlorophyll and carotenoids. The colour of the fruit changes according to the concentrations of these pigments and the interactions between them. [48 61] The synthesis of anthocyanin in pears is affected especially by environmental factors, such as light and heat.[52 54] In our study, the highest level of
anthocya-nin in pear peels was found in ‘Kırmızı’ pear
(20.2 mg/100 g) and the lowest one was found in‘_Incir’ pear genotype (1.4 mg/100 g). In a study, conducted in China, it was reported that the amount of anthocyanin in pear types was 10 mg/100 g.[55] In another study, it was reported that it was 8.95 mg/100 g.[34] Steyn et al. [53,54] indicated that the low temperature increases the anthocyanin abundance, and the high temperature decreases it in European pear cultivars. In our study, the obtained average anthocyanin rate was higher than that in other studies. This can be associated with the low temperatures of the Ardahan region.
Fruits and fruit products are rich sources of antioxi-dants.[56] It is known that some nutrition ingredients found in fruits, such as carotenoids, vitamin C, vitamin E, phenolic components, ascorbic acid and anthocyanin, have an antioxidant activity.[18] Phenolic contents in fruits have an effect as free radical scavengers, especially for DPPH radicals.[57] According to the analyses, it was determined that‘_Incir’ pear’s fruit flesh (25.6%) and fruit peel (20.2%) had the lowest antioxidant activity among the genotypes. ‘Bal’ pear’s fruit flesh (55.4%) and fruit peel (65.3%) had the highest antioxidant activity among the studied genotypes. Rezaeirad et al. [29] reported that in pear’s peels, the antioxidant activity was the
high-est in ‘Amrud’ (67.6%) and lowest in ‘Rashtehkhoj’
(64.3%). In the fruitflesh, the antioxidant activity was the
highest in ‘Zizaling’ (73.6%) and lowest in ‘Amrud’
(42.2%).[29] Manzoor et al. [36] observed that the antiox-idant activity in the fruit peel was 50% and it was 29% in the fruitflesh. There is a report that when the antioxi-dant activity increases, the resistance, quality and stor-age endurance of genotypes also increase.[58]
Cluster analysis
Cluster analysis was performed for the determination of the relationship between variables and was presented as a dendrogram. Eleven parameters (fruit weight, brix8, acidity, pH, productivity, total phenolic content of the peel and flesh, ascorbic acid content of the flesh, total antioxidant activity of the peel andflesh, and total antho-cyanin content of the peel) were clustered in the dendro-gram (Figure 2). The cluster analysis identified three main
clusters of pear varieties. There were 1, 6 and 3 geno-types distributed in three clusters. This result indicated that there was a significant difference between the evalu-ated genotypes for pomological and biochemical traits. Cluster 1 included G€ug€um pear. Cluster 2 included Limon, Kabak, _Imlahor, Kırmızı, Banda, Bal pears and cluster 3 included _Incir, Nene and Baraka pears. The first group had the highest fruit weight. The second group had the highest peel andflesh phenolic contents. The third group had the lowest peel andflesh phenolic contents.
Pearson’s correlation analysis
Correlations between pomological and biochemical traits were also observed (Table 3). There were no corre-lations between anthocyanin, productivity and other fruit quality attributes. Correlations between brix and pH, fruit weight and pH, pH and acidity were found to be significant. In general, fruit weight was positively cor-related with pH.[59,60] Negative significant correlations
Figure 2.Dendrogram of pear varieties according to their pomological and biochemical properties.
were also observed between pH and acidity. Viana et al. [61] also found a negative correlation between pH and titratable acidity (rD ¡0.756). pH was positively
corre-lated with brix and these parameters increased with
fruit ripening.[62,63] This increase in the brix also increases the perceived fruit sweetness, thereby strongly influencing the fruit taste.[64]
In the present study,flesh ascorbic acid content and
peel flesh phenolic content, peel flesh antioxidant
activity and flesh phenolic content, peel phenolic con-tent andflesh phenolic content were found significantly correlated. Koh et al. [65] found that total phenolics cor-related positively and highly with ascorbic acid content (r D 0.608). Similar to our research, different research studies found the positive linear correlation between antioxidant activity and total phenolic content and between total phenolic content and ascorbic acid con-tent.[66,67]
Conclusions
As a consequence of this study, it was concluded that pear genotypes growing in the ecological conditions of Ardahan are rich in phenolic substances, anthocyanin and ascorbic acid contents, and have a high antioxidant activ-ity. The highest amount of phenolic substances and the highest antioxidant activity were observed in the‘Bal’ vari-ety of pears. There was a higher content of phenolic sub-stances and antioxidant activity in the pear genotypes’ peels than in theirflesh. Consumption of pear fruit, con-taining rich bioactive compounds, in a balanced diet will be helpful in protecting the body from harmful oxygen radicals. Moreover, it is also suggested that fruits should be consumed with their peels, because it is thought that the antioxidant activity that they have is effective in pro-tecting the health and preventing diseases.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
This research was supported by the Ardahan University [grant number (2012/07)].
ORCID
Muavviz Ayvaz http://orcid.org/0000-0002-1776-0730
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Table 3.Pearson’s correlation coefficients between pomological and biochemical traits.
Fruit
weight Brix Acidity pH Productivity
Total phenolic content (P) Total phenolic content (F) Ascorbic acid content (F) Antioxidant activity (P) Antioxidant activity (F) Brix8 ¡0.4540 1 Acidity 0.5453 ¡0.5874 1 pH 0.6756 0.7374 ¡0.8384 1 Productivity ¡0.5720 0.4829 ¡0.1666 0.2547 1
Total phenolic content (P) ¡0.2673 ¡0.2581 ¡0.0622 ¡0.1715 0.3045 1
Total phenolic content (F) ¡0.2938 ¡0.1405 ¡0.0627 ¡0.1176 0.3485 0.9265 1
Ascorbic acid content (F) ¡0.0884 ¡0.1757 0.5235 ¡0.4276 0.3359 0.6372 0.7191 1
Antioxidant activity (P) ¡0.1914 ¡0.1912 0.0503 ¡0.1772 ¡0.0615 0.5560 0.7251 0.6050 1
Antioxidant activity (F) ¡0.3496 0.1345 ¡0.2813 0.2898 0.2204 0.5659 0.7584 0.4398 0.6296 1 Total anthocyanin (P) ¡0.2186 ¡0.0670 0.2042 0.1668 0.1327 ¡0.1161 0.0389 0.2124 0.2298 0.4136
Correlations significant at p < 0.05.
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