Original Article

J. Functional Water Vol.16(2), pp.1-9, 2022

Comparative Study of Alkaline Electrolyzed Water and Tourmaline Water
in terms of their Enhancing Effect on the Antioxidant Activity of Ascorbic Acid.
Tongjiao Wu1, Masahiro Hiroshima2, Chinatsu Tachibana2, Mizuki Gaja2,
Ayane Nagahama2, Yoshinori Kamitani 1,2*
1

The United Graduate School of Agricultural Sciences, Kagoshima University and2Graduate School of Agricultural, Forestry and Fisheries, Kagoshima University
1-21-24 Korimoto Kagoshima, 890-0065 Japan
2021.11.17 Received、2021.12.10 Accepted

Abstract: Free radicals are causative factors of lifestyle diseases so that the research on free radical scavengers
and the development of their effective utilization methods are particularly necessary. In this context, somefunctional waters have been reported to possess SOD-like activity, which may remove reactive oxygen species,
inhibit tumor angiogenesis, and protect oxidative damage of DNA and RNA. In the present study, alkaline
electrolyzed water (AlEW) and tourmaline water (TW) were examined for their enhancing effect on theantioxidant activity of ascorbic acid. Consequently, the enhancing effects of these waters were confirmed.
Subsequently, the influence of components of AlEW on the antioxidant activity of ascorbic acid was examined.
It turned out that neither EC nor pH showed linear relationship with the SOD activity. Moreover, H2 bubble
water adjusted to the same pH and EC values as those of AlEW showed SOD activity almost equal to that of
the control, indicating no significant roles of these factors.
Keywords:

Alkaline electrolyzed water; antioxidant effect; SOD activity; tourmaline water

1 Introduction

organism, that is, free radical scavengers. Among them,Lifestyle-related diseases are due to risky behaviors

ascorbic acid is a cofactor in numerous physiologicalto health such as poor diet, smoking, alcoholism, or lackreactions and acts as an antioxidant in biological systems5).

1)of exercise . They include hypertension, hyper-lipidemia,

It can protect the compounds in the extra-cellular andhyperuricemia, diabetes, arteriosclerosis as well as cancer.

intracellular spaces, prevent the damage caused by free

The main reason for lifestyle-related diseases is that anradicals to DNA, and scavenge free radicals6). Hence, it isimbalance between generation of reactive oxygen species

meaningful to study the activity enhancement of(ROS) or free radicals and their scavenging system inantioxidants and effective scavenging of free radicals.

cells leads to oxidative stress2). ROS or free radicals3),

Electrolyzed water is a functional water generated bysuch as singlet oxygen ( O2), superoxide anion radical

the electrolysis of aqueous-solution containing chloride(O·2–)hydrogen peroxide (H2O2) and hydroxyl radicalion (Cl-). It includes acidic electrolyzed water and alkaline(·OH) are highly reactive and potentially capable ofelectrolyzed water (AlEW)7). The latter is also called

damaging transient chemical species formed in aerobic

electrolyzed reduced water (ERW), is produced at thestate, and even cause oxidation of biological macro-cathode upon electrolysis and showed capability ofmolecules such as protein, DNA and enzymes in the body,

extraction and anti-oxidation. Moreover, the AlEW with

1

4)

giving rise to several diseases . On the other hand, there

low oxidation-reduction potential (ORP) has reducibility

is an antioxidant system that relies on endogenousthat might result in scavenging free radicals in biologicalantioxidant enzymes and antioxidant substances in thesystems8). Shin et al.9) reported that daily drinking of* Corresponding author: Yoshinori Kamitani (kamitani@agri.kagoshima-u.ac.jp)
1alkaline-reduced water (ARW) for eight weeks improved

2.1.1. Alkaline electrolyzed water (AlEW) was

the quality of life in patients with diarrhea-predominant

generated by the electrolyzed water generator (model

irritable bowel syndrome (IBS). ERW may also inhibit the

ROX-20TA of Hoshizaki Corporation with sometumor angiogenesis

10)

and protect the liver from carbon

modifications by us. The electrolysis voltage was 10V.

11)

tetrachloride damage . In 1997, Shirahata et al. first

The physico-chemical properties of AlEW were shown inreported that ERW had SOD-like activity, and could

Table 1. Ec, pH, ORP, EC, DO and DH of AlEW 4A, 8A,

protect DNA from oxidative damage12). Lee et al. reported

12A and 16A were measured respectively with Electricalthat ERW could protect against oxidative damage to DNA,

Conductivity meter (CUSTOM, CD-6021A), pH meter13)

RNA and protein . Hanaoka pointed out that ERW could(TPX-999, Toko Chemical Laboratory), ORP meter

improve the activity of antioxidants to scavenge free(silver-silver chloride electrode: TRX-90, Toko Chemical

radicals and ROS. Besides, the hydrogen peroxide

Laboratory), Dissolved Oxygen meter (Mettler-Toledo,

scavenging activity of ERW may depend on the

SG9-ELK) and Dissolved Hydrogen meter (TRUSTLEX,

concentration of activated hydrogen molecules produced

ENH-2000). The particle size of dissolved hydrogen inin the ERW

14).

AlEW ranged 20~560μm.

Tourmaline stone, a natural borosilicate mineral, is

2.1.2. Pure water was generated by pure water

usually expressed as the following chemical formula;generator (Merck Millipore, Elix Essential UV3) with the

XY3Z6Si6O18(BO3)3W4, where X is Na+, Ca2+, K+, orreverse osmosis membrane and continuous ion exchange

2+

2+

2+

3+

3+

3+

3+

3+

so as to get EC value of 2.0µS/cm or less.

3+

vacancy; Y is Mg , Fe , Mn , Al , Fe , Mn , Cr ,-2.1.3. pH-adjusted waters with pH of 8.5, 9.5, 10.5 andF , or O . The electric property of tourmaline stone is11.5 were prepared with 0.1 M NaOH aqueous solution

4+

+

3+

2+

Ti , or Li ; Z is Al , V , Cr , or Mg ; and W is OH ,-2-

(Nacalai Tesque Co., Ltd.).

15)

excellent in thermoelectricity and piezoelectricity . At
present, there are many products related to tourmaline

2.1.4. EC-adjusted water was obtained by adjusting EC

stone treated water (hereafter tourmaline water or TW) on

to 1.9 mS /cm with NaCl (Salt Industry Center of Japan)

the market. They claim that they show weakly alkaline

to match EC of AlEW 8A as shown in Table 1. The NaClproperty and capability of good extraction and dissolution

concentration of EC-adjusted water was set to 0.03-0.2%

similar to these of alkaline electrolyzed water.

(EC 0.6~3.7 mS/cm).

The purpose of this research is to compare alkaline

2.1.5. H₂ bubble water (HB) was generated by using theelectrolyzed water with tourmaline water in terms of theirpump swirling shear type bubble generator (Shoko Tsusho

enhancing effect on the anti-oxidant activity of ascorbic

Co., Ltd., SK20D). Hydrogen gas was eluted in pureacid by using the SOD assay method.

water at a flow rate of 0.4L/min and stirred at 25 ℃ for
30 min.. The particle size distribution of H2 in hydrogen

2 Materials and Methods

bubble water was determined as described in previous

2.1. Solutions

studies. There were two peaks in the distribution curve.

The following solutions each containing 2 mmol/L

The H₂ existence rate of the first peak was 2%, and theascorbic acid were used for SOD assay.

particle size of the hydrogen bubble was 120 μm. The

Table 1. The physico-chemical properties of AlEW
Ec of AlEWpH

ORP(mV)

EC(mS/cm)

DO(mg/L)

DH(ppm)Temp(℃)

4A

10.13±0.1-762±5.7

0.93±0.13

6.0±0.4

0.49±0.725.2±0.2

8A

10.92±0.1-827±7.2

1.91±0.21

3.7±0.6

0.53±0.1

24.8±0.2

12A

11.18±0.1-848±7.6

2.69±0.30

3.6±0.5

0.54±0.1

24.5±0.4

16A

11.46±0.3-872±4.0

3.97±0.09

3.3±0.0

0.56±0.1

24.5±0.5

Ec of AlEW is the electrolysis current of the AlEW; ORP is Oxidation-Reduction Potential; EC is electricalconductance; DO is dissolved oxygen concentration; DH is dissolved hydrogen concentration; Temp is the temperatureof AlEW. Each value is expressed as the mean value ± standard deviation of three replicates.

2

Table 2. The physico-chemical properties of tourmaline water
Temp of TS

pH

ORP(mV)

EC(μS/cm)

DO(mg/L)

DH(ppm)Temp(℃)

25℃

7.3±0.3

216.3±4.9154.1±6.4

7.1±0.70.025.4±0.1

50℃

7.4±0.1

223.7±9.3

150.3±5.4

8.1±0.70.025.4±0.1

75℃

7.4±0.1

253.7±57149.3±6.4

8.8±0.80.025.3±0.1

100℃

7.3±0.1

255.0±56145.8±127.6±0.3

0.0

25.4±0.2

Temp of TS is the temperature of tourmaline stone; ORP is Oxidation-Reduction Potential; EC is electrical conductance
DO is dissolved oxygen concentration; DH is dissolved hydrogen concentration; Temp is the temperature of tourmaline
water. Each value is expressed as the mean value ± standard deviation of three replicates.

second peak showed 12% in existence rate, and themixer, followed by addition of 20 μl of Enzyme working

particle size of the hydrogen bubble was 677 μm. H₂solution. Then, plates were incubated at 37°C for 20

bubble water was adjusted to pH 10.5 and EC 1.9mS/cm

minutes in order to measure the absorbance at 450 nm

similer to these properties of AlEW 8A.

with a plate reader. The SOD Activity (Inhibition Rate %)2.1.6. Tourmaline water (TW) was prepared as follows.

was calculated by following the supplier’s instruction.

770 g of Brazilian tourmaline stone was heated at 25, 50,
75 and 100 ℃ for 30 min. in a water bath and 7.7 L of

2.3 Statistical analysis

pure water was added and circulated for 30 min. at 2.2~
2.4L/minwithmagnetpump.

Each measurement was carried out three times. The

Physico-chemical

results were analyzed by using the One-Way ANOVA ofproperties of TW were summarized in Table 2.

SPSS (Statistical Package for the Social Sciences; SPSS,

2.1.7. Tourmaline-adjusted water was prepared as

Inc, Chicago, IL) software. Statistical significance was set

follows. Tourmaline water (TW) was adjusted to pH 10.5

at a value of P < 0.05.

and EC 1.9mS/cm to match the properties of AlEW as
shown in Table 1.

3 Results
3.1 Effect of electrolysis current of AlEW on SOD activity

2.2. SOD Assay method

The effect of AlEW with different EC on the SOD

In order to examine the above solutions for theiractivity was shown in Fig.1 (A). AlEW4A and AlEW8A

enhancing effect on the anti-oxidant activity of ascorbic

enhanced markedly the activity of SOD. The highest SOD

acid, the SOD Assay Kit-WST (Dojindo) was employed.

activity was 89.7% in AlEW8A. AlEW12A andIn this assay system, superoxide radical-producing

AlEW16A showed significantly lower SOD activities,

reaction by xanthine oxidase (XO) is coupled with thecompared with PW (control).

reducing reaction by WST-1 (tetrazolium salts), resulting

These results might be due to that high current

in the formation of WST-1 formazan (yellow color) andelectrolysis might cause the reduction or loss of theO2. However, coexistence of SOD, which is capable ofantioxidant ability of ascorbic acid itself.

converting superoxide radicals to O2 and H2O2, inhibits
the above coupling reaction. In addition, if any compound

3.2 Effect of NaCl concentration on SOD activity

with radical scavenging activity such as ascorbic acid

Fig. 1(B) shows the effect of NaCl concentrations

coexists, the SOD activity should be apparently increased.

ranging 0.03-0.2% (EC 0.6-3.7 mS / cm), which were

In our study, ascorbic acid was used as the control

equivalent to those of weakly alkaline to strongly alkaline

and the enhancing effect of AlEW and tourmaline waterelectrolyzed waters. Within this range, the SOD activity

were examined. Actually, the following experimental

was 80% or higher, indicating the enhancing effect in allprocedure was carried out.

NaCl concentrations, although no linear relationshipFirst, 20 μl each of sample solutions and the control

between

SOD

activityenhancement

and

NaCl

solution (PW) was filled in wells of the 96-well plate.

concentration was observed. Additionally, there was no

Subsequently, 200 μl of WST working solution was added

significant difference in comparison with the control

to each well and mixed well by pipetting or with plate

(PW).

3

Fig.1. Influence of electrolytic current (A), NaCl concentration (B) and pH (C) on SOD activity.
PW: the control. (A): 4A, 8A, 12A and 16A are Ec. of AlEW (refer to Table 1).
The different letters in (A) indicate significance (p < 0.05). Each value is expressed as the mean value ± standard devitation of three
replicates.

3.3 Effect of pH on SOD activity
The effect of pH on SOD activity was shown in Fig.
1(C). In this experiment, the pH of pH-adjusted water was
targeted at the range of weakly alkaline to strongly
alkaline electrolyzed water. It turned out that the lower the
pH was, the higher the SOD activity. The SOD activity
was highest (87%?) at pH8.5 and lowest (70%) at pH 11.5
that was equivalent to that of PW (control), indicating no
Fig.2. SOD activities of PW, hydrogen bubble water(HB-A) and AlEW 8A.

enhancement effect on the SOD activity. There was no
significant difference between pH8.5 and PW (control).
It was thus unlikely that alkaline pH was not thestability of the HB-A. Dissolved hydrogen (DH)indicator of the antioxidant ability enhancing effect ofconcentration decreased gradually during the storage time

AlEW.

of hydrogen bubble water. However, there was no
significant difference in the SOD activity. Therefore, in

3.4 Effect of hydrogen bubble on SOD activity

this study, hydrogen bubble water was used after

Based on that AlEW 8A (Table1) showed theoperating for 30 minutes at the time of generation.

highest enhancement of SOD activity, hydrogen bubble
100

SOD Activity(%)
1.4

90

those of AlEW 8A was prepared; namely, the pH 10.5, EC
1.9 ms/cm and ORP -557.6±3.2mV. As shown in Fig. 2

DH (ppm)

SOD Activity(%)

80

SOD activities were 67.3%, 67.8% and 89.7% in PW(control), HB-A and AlEW 8A, respectively. Statisticalanalysis indicated that the SOD activities of HB-A and

1.2

70

1

DH (ppm)water (HB-A) with physico-chemical properties similar to

60
0.8

50
40

0.6

30

AlEW 8A were significantly different, whereas no20

substantial difference was observed between PW (control)

10and HB-A, indicating that hydrogen bubble has no

0

0.4
0.2
0
0

30

60

Time (min)substantial effect as an antioxidant.

Fig.3. Stability of SOD activity and dissolved hydrogenconcentration of H2 bubble adjusted water (HB-A).

On the other hand, Fig.3 showed the change of SOD
activity and dissolved hydrogen concentration during the

DH: Dissolved hydrogen concentration, expressed as
the mean value ± standard deviation of three replicates.

storage of hydrogen bubble water. This was to test the

4

(A)

(B)

100

100

a

ab

ab

90
80

SOD Activity (%)

SOD Activity(%)

80

60

40

20

b

b

70
60
50
40
30

20
10

0

0

TW

PW

TW+EC TW+pH TW+HB

TW-A

PW

25℃

75℃

50℃

100℃

Tourmaline stone-treated temperature

Tourmaline waters with adjusted elements

Fig.4. SOD activity of tourmaline waters with various conditions.
(A) PW: control, TW: Tourmaline water produced by treating TS at 25℃, TW+EC: TW with EC-adjusted to that of AlEW,
TW+pH: TW with pH adjusted that of AlEW, TW+HB: H2 bubble adjusted TW with pH 10.5, EC 1.9 mS/cm, TW-A: H2
added TW with the same pH and EC values as those of AlEW.
The different letters indicated significance (P < 0.05). Each value is expressed as the mean value ± standard deviation of
three replicates.
(B) PW: control, 25 ℃~100℃: temperatures for tourmaline stone (TS) treatment for 30 min. to prepare tourmaline waters.

3.5 Effect of tourmaline water on SOD activity

ascorbic acid. The enhancement effect is significantly

The effect of tourmaline water with various elements

different from that of PW (control). Moreover, the SOD

on SOD activity were shown in the Fig.4 (A). Tourmaline

activity of HB-A was significantly lower than that ofwater (TW), tourmaline EC-adjusted water (TW+EC),

AlEW and tourmaline water.

and tourmaline H₂ bubble water (TW+HB) showed SOD
activity (80.4%) higher than that of the PW (control). On
100

water (TW-A) was 68.05%, while tourmaline pH-adjusted

90

water showed the lowest SOD activity. It was therefore

80

SOD Activity (%)

the other hand, the SOD activity of tourmaline-adjusted

suggested that tourmaline water had an enhancing effecton the anti-oxidant activity of ascorbic acid. However theeffect was lowered at the alkaline pH.
The SOD activity of tourmaline water produced by

a

a

a

ab

ab
b

b

70
60
50
40
30
20

treatment at different temperatures of tourmaline stone10

was shown in Fig. 4 (B). SOD activity increased and then0
PW

decreased with the increase of tourmaline treatment
temperature. Based on the results of the significance

HB-A

AlEW
4A

TW
TW
AlEW TW
25℃TW
50℃TWTW
75℃
25℃
50℃
75℃
8A

Fig. 5. SOD activities in H2 bubble adjusted water(HB-A), AlEW and tourmaline waters (TW).

analysis it seemed likely that the SOD activity of TWs(excepted for 100°C) were significantly higher than that

HB-A: H2 bubble adjusted water with pH10.5, EC1.9
mS/cm. AlEW 4A and 8A: AlEW generated underelectrolysis current of 4A and 8A, respectively.
TW25~75℃: tourmaline water (TW) produced by heating
TS at 25~75℃ for 30 min. The different letters indicatedsignificance (P < 0.05). Each value was expressed as themean value ± standard deviation of three replicates.

of the control (PW) group. The peak value 94.25% wasreached with TW 75℃. However, the SOD activity of TW
100 °C was 73.27% indicating no significant difference
from the control group (PW).
3.6 SOD activity comparison of AlEW and TW

4. Discussion

As summarized in Fig. 5, both AlEW and TW

In this study, the enhancing effect of AlEW andenhanced the SOD activity or the antioxidant ability of

tourmaline water on the antioxidant activity of ascorbic

5

acid was examined. The influence of their constituent

consistency of ion species in the solution, NaOH was

factors on the antioxidant activity was also analyzed.

added to pure water as a pH adjuster. A similar conclusion

Consequently, it turned out that both AlEW andin terms of the EC value was obtained. The alkalinity of

tourmaline water were capable of enhancing the anti-

the solutions tested was not a factor for AlEW to enhanceoxidant activity. The SOD activity-enhancing effect of

the antioxidant activity of ascorbic acid.

AlEW increased firstly and then decreased with theAccording to the generation principle of electrolyzed

increase of electrolytic intensity. Similar results werewater, hydrogen is co-produced and dissolved in waterobtained in the experiment using tourmaline water thatduring electrolysis, resulting in the formation of AlEW

may be weakly alkaline. So far, there are several

having increased DH and lowered ORP values12).

hypotheses about the reasons for such function of

Therefore, in this study, hydrogen bubble water was used

tourmaline water, in spite of that they have not been

to simulate the dissolved hydrogen in AlEW, and thescientifically proven. Nevertheless, "tourmaline water isinfluence of ORP on SOD activity was also analyzed. The

similar to AlEW and is beneficial for health" is being

SOD activity of HB-A was approximately the same as thatadvertised for some products. However, based on ourof PW (pure water), indicating that hydrogen could not be

research, it should be remarked that AlEW had higher pH,

the factor to enhance the antioxidant activity. ComparedEC, DH values and lower ORP value than those ofwith pure water, AlEW had significantly enhanced SOD

tourmaline water, as shown in Tables 1 and 2. On theactivity (Fig.2). Hanaoka reported that the behavior of H2

contrary, when the physical properties of tourmaline

in reduced water, which was activated by a platinum

water were compared with those of pure water without

electrode, was different from that of H2 introduced by

tourmaline treatment, no marked difference was observed

bubbling of hydrogen gas14). Alkaline electrolyzed water

except for the EC value. Interestingly, the SOD activity-and HB-AW had approximately the same pH, EC, and H2enhancing effect of tourmaline water and AlEW was

bubbles. Meanwhile, comparing the ORP values of AlEW,

similar.

HB-AW and tourmaline water, they were -827±7.2, -Another our concern is that the tourmaline water

557.6±3.2 and 253.7±57mV, respectively. However, thewithout addition of any substance showed the same SOD

SOD activity of AlEW and tourmaline water was

activity-enhancing effect. It should be noted that thesignificantly higher than that of HB-AW. In other words,

conductivity of the original water is almost 0 so that it

ORP was not a factor for AlEW to enhance the SOD

would be hard to be electrolyzed. Therefore, it isactivity.

necessary to add NaCl as the auxiliary electrolysis agent

Alkaline electrolyzed water, as a kind of drinking

to the water. This was the reason why we studied the SOD

water, had received a big attention. According to Item 360

activity-enhancing effect of alkaline electrolyzed water inof The Ministry of Health, Labor and Welfare No. 112 inorder to elucidate the mechanism. pH, EC and DH are

Japan, the consecutive daily drinking of AlEW produced

characteristic parameters of AlEW. it was verified

by “Water electrolyzer for home use” (JIS T 2004) would

whether alkalinity, NaCl and dissolved hydrogen might

improve gastro-intestinal symptoms such as indigestion,enhance the antioxidant activity of ascorbic acid.

excessive stomach acid17) and chronic diarrhea9).

The concentration of NaCl influences electricalMoreover, Hanaoka postulated that electrolyzed-reduced

conductivity (EC)16), which is one of the physicalwater (AlEW) showed increased dissolving activity 14).

indicators during electrolysis. In our study, similar EC

Thus, at the same temperature, compared with ordinal

data (EC 0.6~3.7mS/cm) were obtained in the range of thedaily drinking water, AlEW might dissolve the drug better,

NaCl concentration (0.03~0.2%) of AlEW. Although theand therefore may maximize the effect of the drug. Our

SOD activity-enhancing effect of EC adjusted water withpresent study demonstrated that AlEW enhanced thea specific EC value was higher than that of pure water, theantioxidant effect of ascorbic acid. Hence, it might bedifference was not significant (Fig. 1(B)). Therefore, itpossible that drinking AlEW might promote scavenging

was conclusive that the EC value has no effect on the SOD

free radicals in human body so as to improve humanactivity of EC-adjusted water. In order to ensure thehealth.

6

Further study should be necessary to analyze thescavenging

anddetoxification

potentials

ofinfluence of temperature changes and other factors on thelophiraalata stem bark extract. Free Radicals &antioxidant activity-enhancing effect of AlEW in order to

Antioxidants, 2011.

elaborate the basic mechanism and to expand the4) AKBARI E. and NAMAZIAN M. Sulforaphane: A

application of AlEW.

natural product against reactive oxygen species.
Computational and Theoretical Chemistry, 2020,

5 Conclusion

1183: 112850.

In this research, AlEW and tourmaline water were

5)

PHILLIPS

K.M.,

COUNCIL-TROCHE

M.,

examined for their effect on antioxidant activity of

MCGINTY R C et al.: Stability of vitamin C in fruit

ascorbic acid. As results, both functional waters enhanced

and vegetable homogenates stored at different

significantly the antioxidant ability of ascorbic acid. Theirtemperatures. J. Food Composition and Analysis,enhancement was stimulated with increase of Ec (Peak2016, 45: 147-162.

stimulation was 8A) of AlEW and treatment temperature(Peak stimulation was 75℃) of tourmaline stone.

6) KALT W., FORNEY C.F., MARTIN A. et al.:Subsequently, the physical properties of these two

anthocyanins after fresh storage of small fruits. J.

functional waters were compared in order to clarify

Agricultural & Food Chemistry, 1999, 47(11): 4638-

factors that brought the difference in EC, pH, and ORP,

44.

Antioxidant capacity, vitamin C, phenolics, andusing NaCl, NaOH and H2 bubble as candidate regulators.

7) RUI L., JIANXIONG H., HAIJIE L. et al. :It turned out that neither EC nor pH value had no linear

Application of electrolyzed functional water on

relationship with the SOD activity-enhancing effect of the

producing mung bean sprouts. Food Control, 2011,adjusted water. In addition, although HB-AW showed the22(8): 1311-1315.

same pH, EC value and hydrogen bubble as AlEW, the8) WANG B., WANG X., FENG H.: Deconstructing

SOD activity was almost equal to that of PW. Based onrecalcitrant miscanthus with alkaline peroxide andthese results, pH, EC and H2 bubbles were not the mainelectrolyzed water. Bioresource Technology, 2010,

factors that enhanced the activity of SOD.

101(2): 752-760.
9) SHIN D.W., YOON H., KIM H.S. et al.: Effects ofConflict of interest

alkaline-reduced drinking water on irritable bowel

The authors have nothing to declare.

syndrome with diarrhea: A randomized double-blind,placebo-controlled

Acknowledgement

pilot

study.

Evidence-based

complementary and alternative medicine : eCAM,

This work was supported by Japanese Government

2018, 2018: 9147914-9147914.

(MEXT) Scholarship.

10) JUN Y.E., YUPING L.I., HAMASAKI T. et al.:Inhibitory effect of electrolyzed reduced water on

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8

アルカリ性電解水とトルマリン水によるアスコルビン酸の SOD 活性
増強効果の比較検討
呉彤嬌 1、廣島誠浩 2、立花知奈津 2、我謝瑞希 2、長濱綾音 2、紙谷喜則 1,2*
１鹿児島大学連合大学院大学

２農林水産学連合講座

体内発生する活性酸素種は、高血圧、高脂血症、高尿酸血症、糖尿病、動脈硬化症、癌などの生活習慣病の一因であると報告されている。そのため、活性酸素種のスカベンジャー物質の探究や効果的な利用方法の開発が求められている。機能水の中には、活性酸素種を除去し、腫瘍の血管新生を阻害し、酸化的ダメージ
から細胞内の DNA、RNA を守ることができる SOD 様活性を持つことが報告されている。本研究では、Lアスコルビン酸（0.2mM）の抗酸化活性に対するアルカリ性電解水とトルマリン水の増強効果について比較研究した。また、抗酸化活性に対するアルカリ性電解水の構成要素の影響を解析した。その結果、水酸化ナ
トリウム濃度（pH 値）、塩分濃度（EC 値）は SOD 活性に濃度依存的な影響を示さなかった。さらに、アルカリイオン水と同様の pH、EC および水素バブルをもつように調整した水素バブル水の SOD 活性は純水(PW)と変わらなかった。以上のことからこれらの因子は、SOD 活性の増強要因ではないと判断された。結論として、アルカリ性電解水とトルマリン水においてアスコルビン酸の抗酸化作用に対する増強効果がみられた。
* 連絡先：紙谷喜則 (kamitani@agri.kagoshima-u.ac.jp)9