The Comparison of Total Fructose and Flavonoids Concentrations in

Fresh Fruits with Different Glycemic Indexes

Herviana Herviana

, Dono Indarto

1,2 b

and Brian Wasita

Postgraduate Program of Nutrition Sciences, Universitas Sebelas Maret, Surakarta, Indonesia

Department of Physiology, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Indonesia

Department of Anatomical Pathology, Faculty of Medicine, Universitas Sebelas Maret, Surakarta, Indonesia

Keywords: Fructose, Flavonoid, Fresh Fruit, Glycemic Index.

Abstract: Obesity is the main risk factor of cardiovascular and diabetes mellitus diseases, leading to the highest

premature death in the world. Fruits consumption is required to keep balance nutrition by providing

macronutrients, vitamins, minerals and fibers. However, different kind of fruits have different sweet taste with

variable fructose levels and bioactive chemical compounds. Therefore, this study aimed to analyze total

fructose and flavonoids concentrations in some fresh fruits with different glycaemic indexes (GIs) to correlate

between fructose and total flavonoids concentration. We choose 9 fresh fruits from local markets with low,

moderate and high GIs. The Pearson test was used to analyze those correlation. We analyzed total fructose

concentration using the Nelson-Somogyi method while flavonoids concentration used a UV-Vis

spectrophotometer. The highest fructose and flavonoids concentrations of fruits in low, moderate and high GI

grous were Fuji apple (9.88±0.12% and 16.18±0.19mg/100g), Golden banana (9.58±0.60%) and California

papaya (34.38±0.09mg/100g) and ripe Ambon banana (10.69±0.04% and 9.74±0.27mg/100g) respectively.

In conclusion, there is no difference total fructose concentration of fresh fruits among GI classification and

there is differenceflavonoids concentration of fresh fruits among GI classification.

1 INTRODUCTION

Diabetes Mellitus (DM) has become the top 5 causes

of death in the world (Andersson & Vasan, 2018).

Based on data from Indonesian Health Research, the

DM prevalence has increased by 4% in 2018

(Kemenkes RI, 2018b). Excess body weight or obesity

is a major risk factor for DM disease (Scherer & Hill,

2016), which can be prevented by implementation of

healthy diet and balanced nutrition (Brandhorst &

Longo, 2019). The healthy diet consists of high

consumption of non-starchy vegetables, fruits, whole

grains, and legumes (Karageorgou et al., 2019). In

general, whole fresh fruits have antioxidant and anti-

inflammatory effects, which are suitable to overcome

low grade inflammation in obesity (Nani et al., 2021).

Moreover, total flavonoids in whole fresh fruits can

improve endothelial function and glycemic

metabolism through protecting β cells in the pancreas,

https://orcid.org/0000-0002-6110-9670

https://orcid.org/0000-0001-7420-5816

https://orcid.org/0000-0002-5501-3541

increasing insulin sensitivity and reducing blood

glucose levels (Pallazola et al., 2019); (Poolsup et al.,

2019).

Indonesia is one of tropical countries that produces

the highest number of tropical fruits in the world

(Putri & Setiawati, 2015). However, the average of

fruits consumption in Indonesian adults is lower than

the recommended fruits consumption. According to

the Central Statistics Agency, Indonesian people

consume only 67g fruits/day, compared to the

recommended fruits consumption from the Indonesian

Ministry of Health (400g/day) (BPS, 2017; Kemenkes

RI, 2018b). Therefore, it is not surprising that low

fruits consumption has a strong association with high

prevalence of non-communicable diseases (Xaba &

Dlamini, 2020).

The main cause of low fruits consumption is due

to the concerns of sweet taste and their impact to

increase blood glucose levels (Davison & Temple,

2018). Basically, sweet taste of fruits is comes from

Herviana, H., Indarto, D. and Wasita, B.

The Comparison of Total Fructose and Flavonoids Concentrations in Fresh Fruits with Different Glycemic Indexes.

DOI: 10.5220/0010759500003235

In Proceedings of the 3rd International Conference on Social Determinants of Health (ICSDH 2021), pages 88-93

ISBN: 978-989-758-542-5

fructose but not glucose, which does not affect blood

glucose levels (Tappy, 2018; Yuliati & Kurniawati,

2017). A recent study showed that fresh fruits

consumption with different GIs have similar effect on

blood glucose levels in diabetes patients (Fitri, 2019).

The fructose concentration in fruits ranges from 5 to

10% but they do not mention in detail related to the

fruits type whether come from tropical countries or not

(Tey et al., 2017). Therefore, the study aim to analyze

total fructose and flavonoids concentrations in some

fresh fruits with different GIs and to correlate between

fructose and total flavonoids concentration.

2 MATERIALS AND METHODS

2.1 Sample Preparation

Nine fresh fruits, which were bought from a local

market, Jebres, Surakarta city were used in this study.

Fuji apple, Medan orange and red guava were

classified as the fruits with low GI. The fruits with

moderate GI were California papaya, honey pineapple

and ripe golden banana while the fruits with high GI

were melon, ripe Ambon banana and watermelon.

In brief, all fresh fruits were thoroughly washed

and then were peeled off to get their flesh. After that,

sliced fruits were crushed using a blender for several

minutes. Finally, fruits juice was poured into a beaker

glass and was ready to further analysis.

2.2 Determination of Fructose

Concentration

To analyze fructose concentrations in each fruit juice,

we used a standard method, the Nelson-Somogyi

assay. One ml fruit juice was diluted into a 50ml final

concentrations. One ml diluted fresh juice was mixed

with 1ml Nelson solution and the mixed solution was

heated for 30 minutes. Then, 1 ml arsenomolybdate

and 7 ml distilled water solutions was added into the

cooled solution. The absorbance of that suspension

was spectrophotometrically measured at 540nm

wavelength and then the fructose concentrations was

calculated using a regression linear with various

concentrations of standard fructose (Al-kayyis &

Susanti, 2016).

2.3 Determination of Total Flavonoid

Concentration

Total flavonoid concentration in fruit juice was

determined using a colorimetric method. Briefly, 1-

2g each fruit juice was added 10 ml of 96% ethanol

to the test tube. After that, 1ml dilluted fruit juice was

mixed with 5ml FeCl

solution until a red color

formation. The red solution was then diluted with

96% ethanol to reach 10ml final concentration and

was directly read in a spectrophotometer with 520nm

wavelength.

2.4 Statistical Analysis

All data collected in this study were presented as

means±standard deviasion (SD). The Shapiro wilk

test was used to verify the data normality and the

correlation of fructose concentrations with total

flavonoids was analyzed using the Pearson

correlation test. The significant value was <0.05.

3 RESULTS AND DISCUSSION

3.1 Different Fresh Fruits Have

Different Fructose Concentrations

Table 1: Fructose concentrations in fresh fruits with

different GIs.

GI Classification Fruits Mean±SD

(w/w%)

Low

i A

le 9.88±0.12

Medan Oran

e 4.10±0.15

Red Guava 3.51±0.02

Moderate

California

6.26±0.04

Honey

Pineapple

3.44±0.10

Ripe Golden

Banana

9.58±0.60

High

Melon 4.57±0.13

Ripe Ambon

Banana

10.69±0.04

Watermelon 5.68±0.25

In this present study, we obtained fructose

concentrations, which ranged from 3.44±0.10 to

10.69±0.04% (Table 1). From GI view point, there

was no difference of fructose concentration in 9 fresh

fruits. Red guava and honey pineapple had the lowest

fructose concentration whereas golden banana, Fuji

apple and ripe Ambon banana had the highest

fructose concentration. The fructose concentration in

other fresh fruits with different GIs varied between

the lowest and the highest concentrations. In general,

the fructose concentrations in mango fruits ranges

from 5 to 10%. This study is in accordance with our

results except red guava, honey pineapple, Medan

The Comparison of Total Fructose and Flavonoids Concentrations in Fresh Fruits with Different Glycemic Indexes

orange and melon of the fructose concentrations test

carried out.

According to Stricker et al (2021), pure fructose

has a lower GI than pure glucose so that our research

findings are in line with the Stricker’s study (Stricker

et al., 2021). In addition, fructose concentration in

fresh fruits is strongly related to the ripe stage. One

recent study stated that fructose in kepok banana

(Musa paradisiaca L) is reducing sugar that becomes

a main substrate for respiration during fruit ripening

process (Irfianti & Sunarharum, 2019; Putra et al.,

2015). Ripe kepok banana has higher fructose

concentration than unripe kepok banana. In our study,

we used ripe fruits such as Ambon banana, golden

banana and Fuji apple while California papaya, honey

pineapple, red guava and melon were half ripe. In

contrast, we used ripe watermelon and Medan orange,

which had low fructose concentration because high

water concentration in both fruit (Kemenkes RI,

2018a). Besides ripening process, Yuliati and

Kurniawati (2017) reported that the different fructose

concentration in each fruit is also influenced by

growth factors, soil type, and nutrient availability

(Yuliati & Kurniawati, 2017). The limitation of our

study is we do not quantify soluble fiber and water

content in fresh fruits, which also affect the fructose

concentration.

3.2 Total Flavonoids in Fresh Fruits

Concentrations

Table 2: Total flavonoid in fresh fruits with different GIs.

GI Classification Fruits Mean±SD

(

/100

Low

i A

le 16.18±0.09

Medan Orange 12.27±0.08

Red Guava 13.98±0.07

Moderate

California

Papaya

34.38±0.09

Honey

Pinea

23.89±0.08

Ripe Golden

Banana

13.46±0.37

High

Melon 5.36±0.15

Ripe Ambon

Banana

9.74±0.27

Watermelon 7.32±0.87

Flavonoids, a member of polyphenols are a bioactive

chemical compound in plants and are also found in

fresh fruits. These compounds generally have

antioxidant activity (Calado et al., 2015). In this

study, we analyzed total flavonoids in 9 different

fresh fruit with low, moderate or high GI. Table 2

indicated that the highest total flavonoids were

detected in the each GI group. Fuji apple, California

papaya and ripe Ambon banana represented the

highest total flavonoids in low, moderate and high

GIs respectively. Moreover, Fuji apple and ripe

Ambon banana had the highest concentration of

fructose and total flavonoids. There were 3 fresh

fruits (melon, watermelon and ripe Ambon banana),

which had the lowest total flavonoids among other

fresh fruits (<10%) but they had the highest GI.

Overall, the highest total flavonoids were found in

California papaya (34.48±0.09%) without GI

consideration.

The results of our study are different from

previous research studies conducted in Indonesia,

Malaysia, and China. Fresh papaya had the lowest

total flavonoids compared to fresh mangoes, bananas

and apples (Khandaker et al., 2018). The second

highest total flavonoids concentrations was honey

pineapple with a total of 23.89%. Based on a research

study carried out in Indonesia, total flavonoids in

pineapple flesh extract was 0.73g QE/100g, higher

than total flavonoids in pineapple peel extract (0.17g

QE/100g) (Fidrianny et al., 2018). In addition,

another study reported that 8 tropical fruits such as

orange, guava, tamarind, strawberry, papaya, mango,

Malang apple and avocado had higher total

flavonoids than 9 tropical fruits in our study. The

highest total flavonoids were observed in fresh

avocado (0.94%) and fresh mango had the lowest

total flavonoids (0.06%) (Febrianti & Sari, 2016).

From a recent study, Fuji apple had 89.7mg/100g

total flavonoids, higher than total flavonoid in our

study (16.18mg/100g) (Li et al., 2020). As mentioned

above, the different total flavonoids in fresh fruits can

be influenced by several factors such as flavonoid

solubility, variety, ripe fruit level, soil type and

altitude (Sholekah, 2017).

3.3 Comparison Total Fructose and

Flavonoids Concentration among

GI Classification

Table 3: Comparison of Total Fructose and Flavonoids

Concentrations among fresh fruits with different GIs.

Classification

Fructose

(w/w%)

Flavonoids

(mg/100g)

Low 5.83±3.51 14.14±1.96

Moderate 6.42±3.07 23.91±10.46

h 6.98±3.2 7.47±2.19

0.914 0.049*

*p-value one way anova

In general, 9 fresh fruits with low, moderate and high

GIs had a different pattern of fructose and total

ICSDH 2021 - International Conference on Social Determinants of Health

flavonoids concentrations (Table 3). The higher GI

classification had the higher mean of fructose

concentration but it was not significant difference

(p=0.914) (Table 3). Theoretically, fructose

concentration in fresh fruits does not affect the GI

because the GI value is defined as the amount of

carbohydrates in fresh fruits that are digested,

absorbed, and metabolized in the human body so that

it affects the increase in blood glucose levels

(Augustin et al., 2015). Therefore, some health

experts suggest that daily consumption of various

fresh fruits help normalize blood glucose levels in

people with type 2 diabetes (Cozma et al., 2012).

Based on Table 3, there are differences flavonoids

concentration in fresh fruits among GI classfication

(p=0,049). Perhaps, that differences in flavonoid

concentrations can be influenced by different types of

fruit and fruit pigments. Fruit pigments such as red

and yellow tend to have higher concentrations of

flavonoids (Wang et al., 2018). In addition to the type

of fruit used, the concentration of flavonoids can be

influenced by nutrients and where a plant grows

(Vicente & Boscaiu, 2018).

3.4 Fructose Concentration Negatively

Correlated with Total Flavonoids

Table 4: Correlations of Fructose Concentration with Total

Flavonoids Concentration in fresh fruits with different GIs

Variable r*

Fructose -0.09 0.80

*correlation coeficient, **p-value Pearson

Table 4 showed that fructose concentration

negatively correlated with total flavonoids in fresh

fruits with different GIs. However, the correlation

was very weak and not statistically significant. From

authors knowledge, we do not find yet any

publication related to fructose and total flavonoids

concentrations. The amount of fruit pigment also

affects the concentration of total flavonoids. For

example, a recent study has compared 16 different

species of cherry fruits. The cherry fruits with red

peel and flesh have the higher concentration of total

flavonoids (Wang et al., 2018). In contrast to the

Wang study, we did not examine the amount of fruit

pigment in 9 fresh fruits. Therefore, we can not

speculate that color pigment in 9 fresh fruits also

affect the total flavonoids concentration.

4 CONCLUSIONS

Fuji apple (9.88±0.12%), Golden banana

(9.58±0.60%) and ripe Ambon banana (10,69±0,04%)

have similar fructose concentrations by which it does

not correlate with GIs. However, California papaya

with lower fructose concentration has the highest total

flavonoids concentration (34.38±0.09mg/100g). There

is no difference total fructose concentration of fresh

fruits among GI classification and there is

differenceflavonoids concentration of fresh fruits

among GI classification. Further pharmacological

analysis of fructose and total flavonoids in fresh fruits

is required to understand their beneficial effects in the

human body.

ACKNOWLEDGEMENTS

We would like to thank all staff in the Laboratory of

Food and Nutrition Study Center, Gadjah Mada

University, Yogyakarta for analyze flavonoid

concentrations. We also appreciate staff in the

Laboratory Food and Nutrition, Agriculture Faculty,

Sebelas Maret University, Surakarta for analyze

fructose concentrations.

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The Comparison of Total Fructose and Flavonoids Concentrations in Fresh Fruits with Different Glycemic Indexes