Use of lactic acid bacteria to increase antioxidant activities of fruits and tea

beverages Amandine FESSARD, Ashish KAPOOR, Theeshan BAHORUN, Emmanuel BOURDON,

Fabienne REMIZE

Les 5èmes rencontres de l’agroalimentaire en Océan Indien – QualiREG 2016 28 novembre 2016 – 2 décembre 2016

IUT de Saint-Pierre, REUNION

CONTENTS

1. Introduction

2. Materials and methods

3. Results and discussion

4. Conclusion

5. Perspectives

2

PROOXYDANTS

ANTIOXIDANTS

Fruits and vegetables (vitamins,

carotenoid, polyphenols…)

Reactive species (oxygen/nitrogen)

Cardiovascular diseases

Cancer

Dammages (proteins, DNA, lipids)

Neurodegenerative diseases

3

1. Introduction

Food, protection against oxydative stress-related diseases

Environmental factors - Pollution - Radiation - Cigarette smoke - Herbicides

Beverages (Fruit juice, tea,

coffee, wine…)

OXYDATIVE STRESS

Carotenoids Vitamins Polyphenols

4

Food antioxidants

- Vitamin C - Vitamin E

- Beta-carotene - Lycopene - Lutein - Zeaxanthine - Beta-criptoxanthin

- Flavonoids - Phenolics acids - Lignan - Stillbene

1. Introduction

E

Exo-polysaccharides

- Procuced by lactic acid bacteria

- High-molecular mass polymers

- Texturizers, viscosifiers

- Antimicrobial action - Lowering of serum

cholesterol & lipids - Anticancer - Antidiabetic - Antioxidative effect

5

1. Introduction

Food processes

• Most fruits and vegetables are eaten after they have been transformed/processed Physical and chemical changes could affect their antioxidant content Most of the compounds are relatively unstable

• Transformation process can induce: - Decrease of vitamins and polyphenol content (pasteurization, blanching, cooking,

sterilization…) - Modification of nutritional properties (preservatives and neoformed compounds) - Improve antioxidant properties (Lactic acid fermentation)

Fruits carbohydrates Lactic acid

• Lactic acid bacteria

• Lactic acid fermentation

Food preservation (safety, shelf-life) Modification of sensorial properties (aromatic compounds) Removal of anti-nutritional factors (cyanogenic glucosides in cassava roots) Mineral and vitamin preservation Improvement of food digestibility

Improvement of antioxidant properties (white cabbage, tomato, cherry, carrot and green beans

smoothies)

6

Lactic acid fermentation of fruits

1. Introduction

Lactic acid + CO2 + Ethanol

Homo-fermentative

Hetero-fermentative

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Lactic acid fermentation of tea

1. Introduction

• Tea beverage One of the most popular beverage worldwide, consumed by over 2/3 of the world’s population daily Rich in antioxidant : flavonoid, particularly tea catechins

• Lactic acid fermentation of tea Tea flavonoids : low bioavailibility Bioconversion of polyphenols possible by lactic acid bacteria Increase of polyphenol bioavailibility and bioactivity • Kombucha, a fermented tea beverage Fermentation of green or black tea with sugar

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1. Introduction

Autochthonous starters for lactic acid fermentation

Technological Sensorial Nutritionnal

Growth rate

Acidification rate Tolerance to salt

Tolerance to low pH and low temperature

Synthesis of antimicrobial compounds

Tolerance to bile salts

Hetero-fermentative

metabolism Synthesis of aromatic

compounds Sensory properties

Synthesis of exo-polysaccharides

No synthesis of biogenic amines

Increase of antioxidant properties

Depolymerization of phenolic compounds

Autochthonous LAB starters: controlled and safe fermentation

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Our objectives

1. Introduction

1. Characterize the lactic acid bacterial flora present on fruits and vegetables grown in Reunion Island

2. Design new fermented food products from fruits and tea in order to keep/improve nutritional and antioxidant properties

Isolation Characterization Starter

selection Production New Fermented foos

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Isolation of 82 LAB from papaya, tomato and sliced cabbage

Genetic, phenotypic and technological characterization

Selection of 29 LAB

Weissella spp

Leuconostoc spp Lactobacillus spp

Fructobacillus spp

Selection of LAB starters

2. Materials & Methods

11

0,000

0,050

0,100

0,150

0,200

0,250

0,300

0,350

0,400

0,450

Gro

wth

(lo

g O

D4

8/O

D0)

Leuconostoc spp

Ability of LAB to grow in apple juice

Weissella spp Lactobacillus spp Fructobacillus spp (77)

Growth in fruit juice

12

Pineapple juice Papaya Mango Green tea Black tea

Fermented tea Catechins oxidized

Not fermented Catechins

Ferulic acid Caffeic acid Para-coumaric acid Protocatechuic acid Chlorogenic acid Rutin Lycopene Β-crytoxanthin

Gallic acid Vanillic acid Protocatechuic acid

Food substrates for lactic acid fermentation

2. Materials & Methods

Para-coumaric acid Caffeic acid Ferulic acid Sinapic acid Hydroxycinnamates Quercétine

13

Lactic acid fermentation of food substrates

2. Materials & Methods

Pasteurized Pineapple juice

(8 LAB isolates + 2 reference strains)

Black tea (21 LAB isolates + 3 reference strains)

Infusion for 5 min (1 tea bag per 250 mL)

+ sucrose

Inoculation DOi = 0.05 UDO/mL

Green tea (17 LAB isolates + 3 reference strains)

Fermentation for 48 h at 30°C

Mango (21 LAB isolates + 3 reference strains)

Papaya (21 LAB isolates + 3 reference strains)

Skin and seeds removal

Inoculation at 1/10

Pasteurization at 80°C for 5 min

Total Polyphenol content (Folin-Ciocalteu assay)

DPPH radical scavenging activity

14

Lactic acid fermentation of food substrates

3. Results & Discussion

0

100

200

300

400

500

600

700

Tota

l po

lyp

hen

ol c

on

ten

t (m

g G

AE/

L)

Results of 3 independent experiments analyzed in triplicate, *** p < 0.001, compared with Control (CTRL)

Lactic acid fermentation of pineapple

0

10

20

30

40

50

60

70

80

FREE

RA

DIC

AL

SCA

VEN

GIN

G A

CTI

VIT

Y (%

DP

PH

RED

UC

ED)

*** *** ***

*** ***

0

5

10

15

20

25

30

Tota

l po

lyp

hen

ol c

on

ten

t (m

g G

AE/

10

0g)

***

75

77

79

81

83

85

87

89

91

93

Free

rad

ical

sca

ven

gin

g ac

tivi

ty (

%

DP

PH

red

uce

d)

15

Lactic acid fermentation of food substrates

3. Results & Discussion

Lactic acid fermentation of papaya

Results of 2 independent experiments analyzed in triplicate, *** p < 0.001, compared with Control (CTRL)

16

Lactic acid fermentation of food substrates

0

20

40

60

80

100

120

140

160

180

Tota

l po

lyp

hen

ol c

on

ten

t (%

of

con

tro

l)

3. Results & Discussion

75

77

79

81

83

85

87

89

91

93

Free

rad

ical

sca

ven

gin

g ac

tivi

ty

(% D

PP

H r

edu

ced

)

* *

Lactic acid fermentation of green tea

Results of 2 independent experiments analyzed in triplicate, * p < 0.05, compared with Control (CTRL)

17

4. Conclusion

82 LAB isolates (Papaya, tomato, sliced cabbage)

21 LAB isolates

Criteria of selection for starters

Lactic acid fermentation

Pineapple juice Papaya Green tea Mango Black tea

5/8 12a, 21, 64: Weissella cibaria

56, DSM20193: Leuc. pseudomesenteroides

1/21 64: W. cibaria

2/21 1,5: Leuc. mesenteroides

0/21 0/21

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5. Perspectives

• Majority of starters used in food insdustries are Lactobacillus species • Weissella and Leuconotoc spp are rarely investigated

Frequently isolated from fruits and vegetables Fast growth High acidifiying activity Produce EPS polymers Tolerent to a multitude of stresses Antioxidant activities

• Weissella and Leuconostoc spp as starters for fruit and tea fermentation ?

19

Acknowledgements