고항산화 활성 락티플란티바실러스 플란타룸 JBCC 108의 프로바이오틱 특성 및 브로콜리 새싹 주스 발효에의 적용 = Probiotic potential of Lactiplantibacillus plantarum JBCC 108 with high antioxidant activity and preparation of fermented broccoli sprout juice with enhanced functional properties

다국어 초록 (Multilingual Abstract)

Lactic acid fermentation of natural food matrices represents a promising bioprocessing strategy that aligns with the increasing consumer interest in functional and health-promoting foods. This fermentation method not only enhances the preservation and sensory properties of food but also promotes the formation and stabilization of bioactive compounds through the metabolic activities of lactic acid bacteria. Lactiplantibacillus plantarum JBCC 108, a strain isolated from the traditional Korean fermented vegetable product “Jangajji”, demonstrated remarkable functional properties, including strong antioxidant activities, as evidenced by ABTS (34.5%), DPPH (43.6%), and SOD (42.0%) assays, along with notable cinnamoyl esterase activity capable of converting phenolic esters into biologically available forms. In addition to its metabolic abilities, L. plantarum JBCC 108 exhibited outstanding probiotic characteristics, such as survival under simulated gastrointestinal stress conditions involving acidic pH and bile salts. The strain also possessed broad antibacterial activity and intrinsic antibiotic resistance, as well as high surface hydrophobicity, which is commonly associated with adhesive potential to intestinal epithelial cells. To evaluate the applicability of this strain for food fermentation, we investigated its use in producing a lactic acid–fermented broccoli sprout juice (fBSJ). The fermented product showed a substantial improvement in antioxidant capabilities compared with the non-fermented control (nfBSJ), accompanied by effective suppression of undesirable microbial proliferation during fermentation. Notably, fBSJ contained approximately 2.9-fold higher sulforaphane content (34.91 μg/mL) than nfBSJ (11.79 μg/mL), a result attributed to the hydrolysis of glucoraphanin, the primary glucosinolate prevalent in broccoli sprouts, by enzymatic activity during fermentation. These findings highlight the potential of L. plantarum JBCC 108 as a functional starter culture for developing novel fermented beverages with enhanced nutritional and biological value.

목차 (Table of Contents)

• Abstract 1
• Ⅰ. INTRODUCTION 3
• 1. Antioxidant activity 3
• 2. Lactiplantibacillus plantarum 6
• 3. Probiotics and prebiotics 8
• 4. Broccoli sprout 9
• 5. Aim of study 11
• Ⅱ. MATERIALS AND METHODS 12
• 1. Isolation of lactic acid bacteria strain from Jangajji 12
• 2. Screening antioxidant activity 14
• 2.1. Antioxidant activity 14
• 2.2. CE activity 16
• 3. Identification of the selected strains by 16S rRNA sequencing 18
• 4. Analysis of cytotoxicity and NO production 19
• 5. Technical probiotic properties 20
• 5.1. Acid and bile tolerance 20
• 5.2. Bile salt hydrolase (BSH) activity 21
• 5.3. Antimicrobial activity 22
• 5.4. Antibiotic resistance 23
• 5.5. Cholesterol assimilation 24
• 5.6. Cell surface hydrophobicity analysis 25
• 5.7. Cell adhesion to Caco-2 intestinal epithelial cell 26
• 5.8. Cell auto-aggregation 27
• 5.9. Pro-inflammatory cytokines (TNF-α and IL-6) by ELISA 28
• 6. Preparation of probiotic fermented broccoli sprouts juice(fBSJ) 29
• 6.1. Preparation of fBSJ by lactic acid bacteria 29
• 6.2. pH and titratable acidity of fBSJ 32
• 6.3. Viable cell count of fBSJ 33
• 6.4. Antioxidant activity of fBSJ 34
• 6.5. Sulforaphane analysis of fBSJ by HPLC 35
• 6.6. Volatile compounds analysis of fBSJ by GC-MS 37
• 6.7. Color of fBSJ 38
• 7. Statistical analysis 39
• Ⅲ. RESULTS AND DISCUSSION 40
• 1. Physicochemical properties of strains isolated from hot pepper Jangajji 40
• 2. Identificaton of the selected LAB strains with CE activity 41
• 3. Inhibition activity of nitric oxide (NO) production 44
• 4. Probiotic properties of L.plantarum JBCC 108 46
• 4.1. Acid and bile salt resistance of L.plantarum JBCC 108 46
• 4.2. Antimicrobial activity and antibiotic resistance of L.plantarum JBCC 108 48
• 4.3. Cholesterol-lowering effect of L.plantarum JBCC 108 51
• 4.4. Bacterial adhesion activity of L.plantarum JBCC 108 53
• 4.5. Immunomodulatory capacity of L.plantarum JBCC 108 55
• 5. Physicochemical and function characteristics of fBSJ by L.plantarum JBCC 108 57
• 5.1. pH and titratable acid of fBSJ 57
• 5.2. Viable cell of fBSJ 59
• 5.3. Antioxidant activity of fBSJ 61
• 5.4. Sulforaphane contents of fBSJ 63
• 5.5. Volatile compounds of fBSJ 65
• 5.6. Color of fBSJ 69
• Ⅳ. CONCLUSION 71
• Ⅴ. REFERENCES 72
• 국문초록 84