Fermented Soy Product Research Articles

Improved analysis of 230 pesticide residues in three fermented soy products by using automated one-step accelerated solvent extraction coupled with GC–MS/MS

Consumer concerns over healthy diets are increasing as a result of the toxicity and persistence of pesticide residues in foodstuffs. Developing sensitive and high-throughput monitoring techniques for these trace residues is seen as an essential step in ensuring food safety. An automatic and sensitive multi-residue analytical method was developed and validated for the simultaneous determination of 230 compounds, including pesticides and their hazardous metabolites, in fermented soy products. The method included preparing the sample using on-line extraction and clean-up system based on accelerated solvent extraction (ASE), then determining the analytes using GC–MS/MS techniques. The homogenized samples (soy sauce, douchi, and sufu) were automatically extracted at 80 °C and 10.3 MPa and at the same time, in situ cleaned by 300 mg of primary secondary amine (PSA) combined with 20 mg of hydroxylated multi-walled carbon nanotubes in an extraction cell. The method obtained excellent calibration linearity (r > 0.9220) and a satisfactory analysis of the targeted compounds, which were evaluated with matrix-matched calibration standards over the range of 5–500 μg L−1. The limit of detections (LODs) of analytes were in the range of 0.01–1.29 μg kg−1, 0.01–1.39 μg kg−1, and 0.01–1.34 μg kg−1 in soy sauce, douchi, and sufu, respectively. The limit of quantifications (LOQs), which defined as the lowest spiking level, were set at 5.0 μg kg−1. The recoveries were within 70–120 % for over 95 % of the analytes, and the relative standard deviations (RSDs) were below 13.6 %. Moreover, a positive detection rate of 47 % were obtained when the proposed method was used on 15 real fermented soy products. These results suggested that the developed high-throughput method is highly feasible for monitoring of these target analytes in trace level.

Low molecular weight peptides in tauco, a fermented soy product, associated to umami taste through peptidomics‐sensomics approach

SummaryUmami peptides from ultrafiltration fractions of tauco have never been revealed yet. This study's objective was to determine umami peptides by peptidomics‐sensomics approach followed by molecular docking on the ultrafiltration fractions of tauco with MWs <3 kDa from different regions of Indonesia. Sensory evaluation by taste dilution analysis to determine umami intensity and peptide identification by HR‐LC–MS/MS were conducted. Seventeen peptides were revealed to be associated with the intense umami taste of tauco fractions, having molecular weights of 1106–1760 Da. The molecular mechanism and binding energy affinity of the peptides to umami receptor T1R1/T1R3 heterodimer through molecular docking confirmed the result. Peptides IPVNKPGRF, DVFRAIPSEV, and DVTDVTGDRGVTVT are 3 of the 17 identified peptides which have the lowest binding energy to umami receptor T1R1/T1R3 at −9.4, −9.2, and −9.1 kcal mol−1, respectively. In addition, the molecular docking results indicated that His145, Asn68, Val277, and Ser67 of taste receptor type 1 member 3, T1R3 subunit, play critical roles in the binding with identified umami peptides by forming hydrogen bonds and hydrophobic interaction.

Soy Product Consumption and the Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies.

The association between soy product consumption and cancer risk varies among studies. Therefore, this comprehensive meta-analysis of observational studies examines the association between soy product consumption and total cancer risk. This study was conducted following the PRISMA guidelines. Up to October 2023, all eligible published studies were searched through PubMed and Web of Science databases. A total of 52 studies on soy product consumption were included in this meta-analysis (17 cohort studies and 35 case-control studies). High consumption of total soy products (RR: 0.69; 95% CI: 0.60, 0.80), tofu (RR: 0.78; 95% CI: 0.70, 0.86), and soymilk (RR: 0.75; 95% CI: 0.60, 0.93) were associated with reduced total cancer risk. No association was found between high consumption of fermented soy products (RR: 1.18; 95% CI: 0.95, 1.47), non-fermented soy products (RR: 0.95; 95% CI: 0.77, 1.18), soy paste (RR: 1.00; 95% CI: 0.88, 1.14), miso soup (RR: 0.99; 95% CI: 0.87, 1.12), or natto (RR: 0.96; 95% CI: 0.82, 1.11) and cancer risk. A 54 g per day increment of total soy products reduced cancer risk by 11%, a 61 g per day increment of tofu reduced cancer risk by 12%, and a 23 g per day increment of soymilk reduced cancer risk by 28%, while none of the other soy products were associated with cancer risk. Our findings suggest that high total soy product consumption, especially soymilk and tofu, is associated with lower cancer risk. More prospective cohort studies are still needed to confirm the causal relationship between soy product consumption and cancer risk.

Significance of Soy-Based Fermented Food and Their Bioactive Compounds Against Obesity, Diabetes, and Cardiovascular Diseases.

Soybean-based fermented foods are commonly consumed worldwide, especially in Asia. These fermented soy-products are prepared using various strains of Bacillus, Streptococcus, Lactobacillus, and Aspergillus. The microbial action during fermentation produces and increases the availability of various molecules of biological significance, such as isoflavones, bioactive peptides, and dietary fiber. These dietary bio active compounds are also found to be effective against the metabolic disorders such as obesity, diabetes, and cardiovascular diseases (CVD). In parallel, soy isoflavones such as genistein, genistin, and daidzin can also contribute to the anti-obesity and anti-diabetic mechanisms, by decreasing insulin resistance and oxidative stress. The said activities are known to lower the risk of CVD, by decreasing the fat accumulation and hyperlipidemia in the body. In addition, along with soy-isoflavones fermented soy foods such as Kinema, Tempeh, Douchi, Cheonggukjang/Chungkukjang, and Natto are also rich in dietary fiber (prebiotic) and known to be anti-dyslipidemia, improve lipolysis, and lowers lipid peroxidation, which further decreases the risk of CVD. Further, the fibrinolytic activity of nattokinase present in Natto soup also paves the foundation for the possible cardioprotective role of fermented soy products. Considering the immense beneficial effects of different fermented soy products, the present review contextualizes their significance with respect to their anti-obesity, anti-diabetic and cardioprotective roles.

Nutraceutical potential of traditional fermented soybean (Hawaijar)

Fermentation not only reduces the toxins but also it is an excellent processing method for improving nutritional and functional properties of soybean due to the increased content of small bioactive compounds. The NEH region of India also has similar traditional fermented soy products. ACE inhibitory activity was found to increase during fermentation and exhibited higher ACE inhibition percent in starter culture strain (H) than starter culture strain (S) of both the soybean used (local small variety and JS-335). Fermentation of soybean with different micro-organisms improve the bio-functional properties due to the increase in free isoflavones and peptides.

Dietary intake and cancer incidence in Korean adults: a systematic review and meta-analysis of observational studies.

Cancer is a major health burden in Korea, and dietary factors have been suggested as putative risk factors for cancer development at various sites. This study systematically reviewed the published literature investigating the associations between dietary factors and cancer incidence among Korean adults, following the Preferred Reporting Items for Systematic Reviews and Meta- Analyses guidelines. We focused on the 5 most studied cancer sites (stomach, colorectum, breast, thyroid, and cervix) as outcomes and dietary exposures with evidence levels greater than limited-suggestive according to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) panel's judgment for any of the cancer sites. This resulted in the inclusion of 72 studies. Pooled estimates of the impact of dietary factors on cancer risk suggested protective associations of fruits and vegetables with risks for gastric cancer (GC), colorectal cancer (CRC), and breast cancer (BC) and dietary vitamin C with the risk of GC, as well as a harmful association between fermented soy products and the risk of GC. Despite the limited number of studies, we observed consistent protective associations of dietary fiber with GC and dietary fiber, coffee, and calcium with CRC. These findings are largely consistent with the WCRF/AICR expert report. However, pooled estimates for the associations of other salt-preserved foods with GC, meat with CRC, and dietary carotenoids and dairy products with BC did not reach statistical significance. Further studies with prospective designs, larger sample sizes, and diverse types of dietary factors and cancer sites are necessary.

Zero Waste Technology of Soybeans Processing

Soybean can be easily digested and is a valuable substitute for animal protein in various applications. That is why soy products are a very important component of a vegan and vegetarian diet. During soymilk processing, large quantities of by-products are generated. Hardly anyone knows that every kilogram of dried soybeans processed into soymilk or tofu gives about 1.2 kg of soybean curd residue, namely, okara, often regarded as a waste. Acting in the spirit of zero waste, a soybean processing technology has been developed that does not generate waste. The developed technology consists of obtaining soymilk followed by filtration to remove the insoluble residues (okara), preparing okara and fermenting to obtain vegan soft cheese. Samples analyzed for physical, chemical, and organoleptic properties. Also, the microbial quality of the obtained products was tested. Soy products produced with the proposed zero waste technology were assessed by the sensory panel and received very good marks. Fermented soy products are characterized with high levels of Lactobacillus spp. (105–108 cfu/mL), thus consuming them can bring health benefits. Cheese made from okara can be an alternative to cheeses currently obtained from soymilk.

Determination of γ-aminobutyric acid in fermented soybean products by HPLC coupled with pre-column derivatization

This study reports a pre-column derivatization HPLC stragety to determine the content of GABA in fermented soybean products. 9-Fluorenylmethyloxycarbonyl chloride (Fmoc-Cl) is employed as the derivative reagent with chromophore linked to GABA, which lacks of chromophore for UV/DAD analysis in its pristine structure. After the detection wavelength was confirmed, the derivatization and analysis conditions were also optimized, including pH and amount of boric acid buffer, amount of derivative reagent, the mobile phases and their gradient. Methodological investigation showed that the derivatized GABA (Fmoc-GABA) has good linearity in the range of 1–100 µg/mL, low limit of quantification (LOQ, at 1 µg/mL) and limit of detection (LOD, at 0.3 µg/mL), and good recoveries of three spiked levels (between 83.8% and 100.8% with RSDs less than 5%). Furthermore, thirty-two commercial fermented soy products in four matrices (soy sauce, soy paste, bean curd, lobster sauce) were analyzed by the proposed method for validation. As a consequence, the concentrations of GABA in these soy products were in the range of 48.4–381 mg/kg.

Association of Fermented Products with Risk of Cancer Recurrence and Mortality among Breast Cancer Survivors: A Prospective Cohort Study

We hypothesized that the intake of fermented soy and dairy products, but not fermented vegetable products, was associated with reduced cancer recurrence and mortality in breast cancer survivors. Women (n = 606) who underwent dietary survey using a 24-h recall within 3 years of breast cancer surgery were recruited, and were followed up for a mean of 89 mo,. Cox proportional hazards regression analysis showed that the risk of cancer recurrence was inversely associated with the intake of fermented soy products (Hazard ratios (HRs):0.976, 95% confidence intervals (CI):0.95–0.99) and fermented dairy products (HRs:0.992, 95% CI:0.98–0.99). Furthermore, the risk of cancer recurrence was inversely associated with the intake of fermented soy products in hormone receptor-positive (HRs:0.296, 95% CI:0.11–0.79), estrogen receptor-positive (HRs:0.971, 95% CI:0.94–0.99), and progesterone receptor-positive (HRs:0.972, 95% CI:0.94–0.99) patients. Mortality was inversely associated with the intake of fermented soy products (HRs:0.967, 95% CI:0.93–0.99). Disease-free survival (P = 0.001) and overall survival (P = 0.004) were positively associated with intake of fermented soy products. Intake of fermented vegetable products had no significant effect on cancer recurrence or mortality. This study suggests that the intake of fermented soy and dairy could be beneficial in preventing cancer recurrence.

Plant-based meat analogue of soy proteins by the multi-strain solid-state mixing fermentation

In order to mitigate or reduce global environmental concerns, health issues, sustainability and animal welfare issues, artificial meat presents a potential solution to consumers' demand for meat. In this study, strains such as Rhodotorula mucilaginosa and Monascus purpureus that can produce meat-like pigments were first identified and used in soy protein plant-base fermentation, where fermentation parameters as well as inoculum size were determined to simulate plant-base meat analogue (PBMA). Meanwhile, the resemblance between the fermented soy products and the fresh meat was examined in terms of color, texture, and flavor characteristics. Furthermore, the addition of Lactiplantibacillus plantarum can perform reassortment and fermentation simultaneously to improve the quality of soy fermentation products in terms of texture and flavor. The results offer a novel way to produce PBMA and also shed light on future research into plant-based meat-like products with the appropriate meat characteristics.

Two sides of the same coin: Meta-analysis uncovered the potential benefits and risks of traditional fermented foods at a large geographical scale.

Traditional fermented foods, which are well-known microbial resources, are also bright national cultural inheritances. Recently, traditional fermented foods have received great attention due to their potential probiotic properties. Based on shotgun metagenomic sequencing data, we analyzed the microbial diversity, taxonomic composition, metabolic pathways, and the potential benefits and risks of fermented foods through a meta-analysis including 179 selected samples, as well as our own sequencing data collected from Hainan Province, China. As expected, raw materials, regions (differentiated by climatic zones), and substrates were the main driving forces for the microbial diversity and taxonomic composition of traditional fermented foods. Interestingly, a higher content of beneficial bacteria but a low biomass of opportunistic pathogens and antibiotic resistance genes were observed in the fermented dairy products, indicating that fermented dairy products are the most beneficial and reliable fermented foods. In contrast, despite the high microbial diversity found in the fermented soy products, their consumption risk was still high due to the enrichment of opportunistic pathogens and transferable antibiotic resistance genes. Overall, we provided the most comprehensive assessment of the microbiome of fermented food to date and generated a new view of its potential benefits and risks related to human health.

Fermented Soy Products and Their Potential Health Benefits: A Review.

In the growing search for therapeutic strategies, there is an interest in foods containing natural antioxidants and other bioactive compounds capable of preventing or reversing pathogenic processes associated with metabolic disease. Fermentation has been used as a potent way of improving the properties of soybean and their components. Microbial metabolism is responsible for producing the β-glucosidase enzyme that converts glycosidic isoflavones into aglycones with higher biological activity in fermented soy products, in addition to several end-metabolites associated with human health development, including peptides, phenolic acids, fatty acids, vitamins, flavonoids, minerals, and organic acids. Thus, several products have emerged from soybean fermentation by fungi, bacteria, or a combination of both. This review covers the key biological characteristics of soy and fermented soy products, including natto, miso, tofu, douchi, sufu, cheonggukjang, doenjang, kanjang, meju, tempeh, thua-nao, kinema, hawaijar, and tungrymbai. The inclusion of these foods in the diet has been associated with the reduction of chronic diseases, with potential anticancer, anti-obesity, antidiabetic, anticholesterol, anti-inflammatory, and neuroprotective effects. These biological activities and the recently studied potential of fermented soybean molecules against SARS-CoV-2 are discussed. Finally, a patent landscape is presented to provide the state-of-the-art of the transfer of knowledge from the scientific sphere to the industrial application.

Fermentation of soymilk by Lactobacillus acidipiscis isolated from Chinese stinky tofu capable of efficiently biotransforming isoflavone glucosides to dihydrodaidzein and dihydrogenistein.

The soy isoflavone microbial metabolites dihydrodaidzein (DHD), dihydrogenistein (DHG), equol and 5-hydroxy-equol are generally more biologically active than their precursors daidzein and genistein. Bacteria responsible for isoflavone metabolism have been isolated and identified. Fermented soymilk is a potential functional food; however, there are few lactic acid bacteria capable of metabolizing soy isoflavones. A newly isolated Gram-positive facultative anaerobic bacterium, which was named Lactobacillus acidipiscis HAU-FR7, was isolated from the traditional Chinese fermented soy product 'stinky tofu'. Bacterium strain HAU-FR7 can grow under aerobic conditions and can also convert most of the daidzin and genistin in soymilk into DHD and DHG, respectively. The concentrations of DHD and DHG produced were 183 and 134 μmol L-1 , respectively, after fermentation for 24 h. Strain HAU-FR7 does not produce the biogenic amines cadaverine, putrescine, histamine or tyramine, and an antibiotic susceptibility test showed that HAU-FR7 is sensitive to nine of the ten tested antibiotics, except for vancomycin. Moreover, the 1,1-diphenyl-2- picrylhydrazyl free radical scavenging capacity of soymilk fermented with HAU-FR7 was significantly higher than that of unfermented soymilk. A facultative anaerobic lactic acid bacterium, designated Lactobacillus acidipiscis HAU-FR7, is capable of reducing the soy isoflavone glucosides daidzin and genistin in soymilk to DHD and DHG efficiently, even in the presence of atmospheric oxygen. The biotransformation activity of HAU-FR7 grown in soymilk is higher than that in de Man-Rogosa-Sharpe liquid culture medium. © 2022 Society of Chemical Industry.

Changes in Isoflavone Profile from Soybean Seeds during Cheonggukjang Fermentation Based on High-Resolution UPLC-DAD-QToF/MS: New Succinylated and Phosphorylated Conjugates.

In this study, thirty-eight isoflavone derivatives were comprehensively identified and quantified from the raw, steamed and fermented seeds of four selected soybean cultivars based on UPLC-DAD-QToF/MS results with reference to the previously reported LC-MS library and flavonoid database, and summarized by acylated group including glucosides (Glu), malonyl-glucosides (Mal-Glu), acetyl-glucosides (Ac-Glu), succinyl-glucosides (Suc-Glu) and phosphorylated conjugates (Phos) in addition to aglycones. Among them, Suc-Glu and Phos derivatives were newly generated due to fermentation by B. subtilis AFY-2 (cheonggukjang). In particular, Phos were characterized for the first time in fermented soy products using Bacillus species. From a proposed roadmap on isoflavone-based biotransformation, predominant Mal-Glu (77.5–84.2%, raw) decreased rapidly by decarboxylation and deesterification into Ac-Glu and Glu (3.5–8.1% and 50.0–72.2%) during steaming, respectively. As fermentation continued, the increased Glu were mainly succinylated and phosphorylated as well as gradually hydrolyzed into their corresponding aglycones. Thus, Suc-Glu and Phos (17.3–22.4% and 1.5–5.4%, 36 h) determined depending on cultivar type and incubation time, and can be considered as important biomarkers generated during cheonggukjang fermentation. Additionally, the changes of isoflavone profile can be used as a fundamental report in applied microbial science as well as bioavailability research from fermented soy foods.

Fermented Soy Drink (Q-CAN® PLUS) Induces Apoptosis and Reduces Viability of Cancer Cells

This study tested the ability of a fermented soy product to induce tumor cell toxicity and to assess if this was due to fermentation of soy, and to the genistein content. Four cancer cell lines were cultured without additive, with fermented soy (Q-CAN® PLUS), nonfermented soy, or genistein, and cell viability was examined at 24 h, 48 h, and 72 h. The sensitivity of the cell lines to apoptosis by Q-CAN PLUS was tested with the Annexin V assay. All cell lines demonstrated a dose and time response reduction in tumor cell viability with exposure to Q-CAN PLUS (IC50 at 24 h 3.8 mg/mL to 9 mg/mL). Unfermented soy did not show reduction in viability of any cell line within the same concentration range. The IC50 of genistein for each of the cell lines was significantly greater than for Q-CAN PLUS. All four tumor cell lines demonstrated apoptosis in response to Q-CAN PLUS. Q-CAN PLUS reduces viability and increases apoptosis of cancer cells in a concentration- and fermentation-dependent manner. Taking into consideration the IC50 of genistein and the concentration of genistein in Q-CAN PLUS, the genistein content of Q-CAN PLUS is not responsible for the majority reduction in tumor cell viability. This suggests that fermentation of soy results in the production of metabolites that reduce cancer cell viability and induce cellular apoptosis, and play a major role in addition to any effects produced by their genistein content.

Integrated Metabolomics and Volatolomics for Comparative Evaluation of Fermented Soy Products.

Though varying metabolomes are believed to influence distinctive characteristics of different soy foods, an in-depth, comprehensive analysis of both soluble and volatile metabolites is largely unreported. The metabolite profiles of different soy products, including cheonggukjang, meju, doenjang, and raw soybean, were characterized using LC-MS (liquid chromatography–mass spectrometry), GC-MS (gas chromatography–mass spectrometry), and headspace solid-phase microextraction (HS-SPME) GC-MS. Principal component analysis (PCA) showed that the datasets for the cheonggukjang, meju, and doenjang extracts were distinguished from the non-fermented soybean across PC1, while those for cheonggukjang and doenjang were separated across PC2. Volatile organic compound (VOC) profiles were clearly distinct among doenjang and soybean, cheonggukjang, and meju samples. Notably, the relative contents of the isoflavone glycosides and DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one) conjugated soyasaponins were higher in soybean and cheonggukjang, compared to doenjang, while the isoflavone aglycones, non-DDMP conjugated soyasaponins, and amino acids were significantly higher in doenjang. Most VOCs, including the sulfur containing compounds aldehydes, esters, and furans, were relatively abundant in doenjang. However, pyrazines, 3-methylbutanoic acid, maltol, and methoxyphenol were higher in cheonggukjang, which contributed to the characteristic aroma of soy foods. We believe that this study provides the fundamental insights on soy food metabolomes, which determine their nutritional, functional, organoleptic, and aroma characteristics.

The Fermented Soy Product ImmuBalanceTM Suppresses Airway Inflammation in a Murine Model of Asthma.

The fermented soy product ImmuBalance contains many active ingredients and its beneficial effects on some allergic diseases have been reported. We hypothesized that ImmuBalance could have potential effects on airway inflammation in a murine model of asthma. Mice sensitized and challenged with ovalbumin developed airway inflammation. Bronchoalveolar lavage fluid was assessed for inflammatory cell counts and levels of cytokines. Lung tissues were examined for cell infiltration and mucus hypersecretion. Oral administration of ImmuBalance significantly inhibited ovalbumin-induced eosinophilic inflammation and decreased Th2 cytokine levels in bronchoalveolar lavage fluid (p < 0.05). In addition, lung histological analysis showed that ImmuBalance inhibited inflammatory cell infiltration and airway mucus production. Our findings suggest that supplementation with ImmuBalance may provide a novel strategy for the prevention or treatment of allergic airway inflammation.

Fatty Acid Composition, Antinutritional Factors, and Oligosaccharides Concentration of Hawaijar (An Ethnic Fermented Soyfood of India) As Affected by Genotype and Bacillus Subtilis Strain

Hawaijar is an ethnic fermented soy product from the North-East region of India. The information on the effect of soybean genotype and the Bacillus subtilis strain used for inoculation for preparing the product on the fatty acid composition, the level of antinutritional factors, such as Kunitz trypsin inhibitor (KTI) and Bowman-Birk inhibitor (BBI), and oligosaccharides is not available. In the present study, Hawaijar was prepared from two soybean genotypes using two different strains of Bacillus subtilis and investigated for the concentration of the above-mentioned biomolecules. The results showed the significant effect of genotype used on oleic, linoleic, and α-linolenic acid of the product. KTI and BBI were found absent in Hawaijar prepared from these two genotypes and two strains. Flatulence-inducing factors like raffinose and stachyose were found in very low concentration irrespective of genotype and strain. Retention of sweetness-imparting sucrose and maltose concentration in Hawaijar was genotype-dependent.

Consumption of Fermented Soy Products Was Inversely Associated With the Risk of Hypertension in Postmenopausal Women and Men Aged ≥50 Years

Abstract Objectives Sodium is known to positively relate with hypertension risk; however, the association of fermented soy products, a major source of salt in Korea, with hypertension risk and blood pressure (BP) has not been reported. The present study aimed to investigate the hypothesis that hypertension risk and BP were inversely associated with the intake of fermented soy products but not with the intake of sodium from fermented soy products. Methods This cross-sectional study was performed using data from the Korea National Health and Nutrition Examination Survey (2013–2018). In total, 11,566 men and postmenopausal women aged ≥50 years were divided according to quintiles of sodium or fermented soy product intake. Results In multivariable adjusted models, the intake of fermented soy products was negatively associated with hypertension risk (odds ratio: 0.81, 95% confidence interval: 0.66–0.98; p-trend = 0.023) and systolic BP (SBP; p-trend = 0.043) in postmenopausal women. Mediation analysis showed significant total and direct effects between the intake of fermented soy products and SBP; however, there was no indirect effect because soy nutrients, such as protein, fiber, calcium, and potassium, had no significant effects on SBP. Among men, fermented soy product intake was not associated with hypertension risk and BP. Additionally, the intake of sodium from fermented soy products was not significantly associated with hypertension risk and BP in both postmenopausal women and men. Conclusions This study suggested that hypertension risk and BP were not associated with the intake of sodium from fermented soy products; further, hypertension risk and BP were inversely associated with fermented soy product intake in postmenopausal women. Further clinical studies are needed to confirm the effect of fermented soy product intake on hypertension risk and BP. Funding Sources This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT).

Fermented Soy Products: Beneficial Potential in Neurodegenerative Diseases

Fermented soybean products, such as cheonggukjang (Japanese natto), doenjang (soy paste), ganjang (soy sauce), and douchi, are widely consumed in East Asian countries and are major sources of bioactive compounds. The fermentation of cooked soybean with bacteria (Bacillus spp.) and fungi (Aspergillus spp. and Rhizopus spp.) produces a variety of novel compounds, most of which possess health benefits. This review is focused on the preventive and ameliorative potential of fermented soy foods and their components to manage neurodegenerative diseases, including Alzheimer’s and Parkinson’s diseases.