Antioxidant Activity of Isoflavone Aglycone from Fermented Black Soymilk Supplemented with Sucrose and Skim Milk Using Indonesian Indigenous Lactic Acid Bacteria

Black soybeans contain high antioxidant compounds such as isoflavone but mainly in glucoside form, with low antioxidant activities. Fermentation by lactic acid bacteria (LAB) can enhance the antioxidant properties, but its ability is strain-dependent. This study aims to study the ability of Indonesian indigenous LAB, Lactiplantibacillus plantarum WGK 4, Streptococcus thermophilus Dad 11, and Lactiplantibacillus plantarum Dad 13, to enhance the antioxidant properties during black soy milk fermentation. Fermentation was carried out at 37 °C for 24 h. Viable cell, acid production, Folin–Ciocalteu assay, antioxidant activity (DPPH), isoflavone aglycone daidzein and genistein, and β-glucosidase activity were measured every six hours. All LAB strains could grow well during the fermentation of black soy milk. Lactiplantibacillus plantarum WGK 4 produced the highest acid (1.50%). All three LAB strains could enhance antioxidant activity (DPPH) from 24.90% to 31.22–38.20%, followed by increased isoflavone aglycone. All strains could increase daidzein and genistein content, ranging from 61% to 107% and 81% to 132%, respectively. All three Indonesian indigenous LAB enhanced antioxidant properties of black soy milk relatively at the same level and potentially could be used as a starter culture of black soy milk fermentation.

Background and objective Fermented soy products were regarded as healthy foods and hence are considered an essential part of the diet. Lactic acid bacteria isolated from naturally fermented Egyptian food products were screened for their ability to produce β-glucosidase, isoflavone aglycone, phenolics, and antioxidant activity during the formation of soy yogurt. The present research is a preliminary attempt to ascertain soy yogurt production by different strains of lactic acid bacteria and their efficacy for the production of the aforementioned products. Materials and methods A total of 16 probiotic lactic acid bacteria were used for the preparation of soy yogurt and tested for their probiotic properties. Soymilk was prepared and inoculated (1% v/v) with the probiotic strains previously activated in the MRS medium. After fermentation, cell viability, pH, titratable acidity, total phenolic compounds concentration, antioxidant activity, isoflavones aglycone (daidzein and genistein), and extracellular and cell membrane-bound β-glucosidase activity were determined. Results and conclusion A total of 16 probiotic lactic acid bacteria were used for the preparation of soy yogurt. The final pH of the fermented soymilk ranged from 4.92 to 6.6, and their titratable acidity (lactic acid %) ranged from 0.5 to 0.99%. Changes in β-glucosidase, isoflavone aglycone, total phenolics content, and antioxidant activity during the formation of soy yogurt were determined. All bacterial isolates showed positive cell-bound and extracellular β-glucosidase. Their activities ranged from 308.65 to 553 mU/ml. The Lactobacillus strains showed lower extracellular than their cell-bound β-glucosidase, and the opposite was true for the other group. An increase in the content of isoflavone aglycones in soy yogurt could be achieved by aging with bacterial fermentation. Soymilk fermented with Lactobacillus strains showed the highest bioconversion of isoflavone glucosides into isoflavone aglycones than other strains, although they produced less β-glucosidase enzymes. The antioxidant activity is related to changes in total phenolics. All microorganisms were able to increase the total phenols, whereas some Lactobacillus strains were unable to release more phenols compared with unfermented soymilk.

Elaeocarpus serratus L. leaves (EL) containing phenolic compounds and flavonoids, including myricitrin with pharmacological properties, could be valorized as nutritional additive in foods. In this study, the semi-solid-state fermentation of EL and black soymilk (BS) by Lactobacillus plantarum BCRC 10357 was investigated. Without adding EL in MRS medium, the β-glucosidase activity of L. plantarum quickly reduced to 2.33 ± 0.15 U/mL in 36 h of fermentation; by using 3% EL, the stability period of β-glucosidase activity was prolonged as 12.94 ± 0.69 U/mL in 12 h to 13.71 ± 0.94 in 36 h, showing positive response of the bacteria encountering EL. Using L. plantarum to ferment BS with 3% EL, the β-glucosidase activity increased to 23.78 ± 1.34 U/mL in 24 h, and in the fermented product extract (FPE), the content of myricitrin (2297.06 μg/g-FPE) and isoflavone aglycones (daidzein and genistein, 474.47 μg/g-FPE) at 48 h of fermentation were 1.61-fold and 1.95-fold of that before fermentation (at 0 h), respectively. Total flavonoid content, myricitrin, and ferric reducing antioxidant power in FPE using BS and EL were higher than that using EL alone. This study developed the potential fermented product of black soymilk using EL as a nutritional supplement with probiotics.

The best starter culture for fermented black soymilk was determined. Black soymilk was fermented using Lactobacillus acidophilus ATCC 4356 (LA), Lactobacillus plantarum P8 (LP), and Streptococcus thermophilus S10 (ST). An ST single culture exhibited higher β-glucosidase activities than LAST (LA:ST=1:1, v/v), LPST (LP:ST=1:1, v/v), and LALPST (LA:LP:ST=1:1:1, v/v) mixed cultures. The pH of fermented black soymilk was significantly (p<0.05) decreased during fermentation due to an increase in lactic acid formed by lactic acid bacteria. The β-glucosidase activity of the ST single culture was significantly (p<0.05) higher than for mixed cultures. Black soymilk fermented with ST alone showed significantly (p<0.05) more bioconversion of the isoflavone glycoside to aglycone, compared with controls. Black soymilk fermented with ST resulted in the best antioxidant effect. The ST single culture was best for production of health functional fermented black soymilk.

BACKGROUND: Soy yoghurts containing enhanced bioactive isoflavone aglycones were prepared from combinations of yellow (YS) and black soymilk (BS) (YS:BS = 100:0, 70:30, 50:50 and 0:100, v/v) by fermentation with Streptococcus infantarius 12 and Weisellia sp. 4 at 37 °C for 10 h. Sensory properties of the bioactive soy yoghurts were investigated. Furthermore, other characteristics including the contents of isoflavones, viable cell numbers, pH, colour and DPPH radical scavenging activity were investigated.RESULTS: One hundred percent YS yoghurt showed the highest scores of all sensory attributes while 100% BS yoghurt was the lowest for colour and smoothness. The overall acceptability scores were 5.9 and 5.2 for 100% YS and 100% BS yoghurts, respectively (9‐point scale). The L‐values of soy yoghurts decreased as the percentage BS increased, indicating darkening of soy yoghurts. The contents of bioactive isoflavone aglycones (daidzein and genistein) in soy yoghurts remarkably increased (&gt;1300 mg kg−1) by fermentation. Viable cell numbers and pH of soy yoghurts ranged from 8.4 × 108 to 9.6 × 108 CFU g−1 and 4.43 to 4.54, respectively. DPPH radical scavenging activity significantly increased as the percentage BS increased (P &lt; 0.05).CONCLUSION: One hundred percent YS yoghurt was better for overall sensory properties while 100% BS yogurt was more bioactive in terms of the isoflavone aglycone contents and DPPH radical scavenging activity compared to other yoghurts. Copyright © 2008 Society of Chemical Industry

Black soybean germination or fermentation increases active ingredient bioavailability and anti-oxidative activity. This study investigated the effects of fermented and germinated black soy milk on anti-oxidation and melanogenesis inhibition. The total phenolic content (TPC; 42.66 ± 1.65 mg gallic acid equivalent/g) and total flavonoid content (TFC; 5.43 ± 0.54 mg quercetin equivalent (QE)/g) in ethanol extracts from Lactobacillus plantarum TWK10 (TWK10)-fermented nongermination black soy milk (FNGB) were significantly (p &lt; 0.05) higher than those in ethanol extracts from nonfermented-nongermination black soy milk (NNGB). Although the TPC of ethanol extracts from nonfermented-germination black soy milk (NGB) and fermented-germination black soy milk (FGB) were not significantly different (p &gt; 0.05), the TFC of FGB (1.79 ± 0.08 mg QE/g) was significantly higher than that of NGB (p &lt; 0.05). The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of ethanol extracts from NNGB, FNGB, NGB, and FGB was significantly higher than that of water extracts at 10 mg/mL (p &lt; 0.05). Furthermore, ethanol extracts from both FNGB and FGB significantly reduced the melanin content in zebrafish embryos at 100 µg/mL (p &lt; 0.05) without causing death, malformation or bradycardia. Overall, the antioxidant activity of black soy milk significantly increased after TWK10 fermentation; moreover, ethanol extracts from FNGB and FGB could inhibit melanogenesis, indicating their potential as whitening ingredients.

Synbiotic products are a combination of probiotics and prebiotics in food that work synergistically to enhance the survival of beneficial microbes and provide greater health benefits. Durian contains simple sugars, dietary fiber, and oligosaccharides that can be utilized by probiotics as a nutrient source for their growth. This study aims to evaluate the potential of durian (Durio zibethinus) as a prebiotic ingredient in the formulation of synbiotic yoghurt by observing its effects on fermentation characteristics, including microbiological, chemical, and sensory properties, when combined with different concentrations of skim milk and sugar (0%, 5%, and 10%). Total bacteria, lactic acid bacteria (LAB), and titratable acidity increased, while the pH value of the product decreased during the fermentation process. The addition of skim milk and sugar influenced the sensory profile of the product, with the best treatment observed in skim milk and sugar 5% (P8), ba Synbiotic products are a combination of probiotics and prebiotics in food that work synergistically to enhance the survival of beneficial microbes and provide greater health benefits. Durian contains simple sugars, dietary fiber, and oligosaccharides that probiotics can utilize as a nutrient source for their growth. This study aims to evaluate the potential of durian (Durio zibethinus) as a prebiotic ingredient in the formulation of synbiotic yoghurt by observing its effects on fermentation characteristics, including microbiological, chemical, and sensory properties, when combined with different concentrations of skim milk and sugar (0%, 5%, and 10%). Total bacteria, lactic acid bacteria (LAB), and titratable acidity increased, while the pH value of the product decreased during the fermentation process. The addition of skim milk and sugar influenced the sensory profile of the product, with the best treatment observed in skim milk and sugar 5% (P8), based on hedonic scores for aroma, texture, and taste of the yoghurt after 24 hours of fermentation. Contribution to Sustainable Development Goals (SDGs):SDG 2: Zero HungerSDG 3: Good Health and Well-beingSDG 9: Industry, Innovation, and InfrastructureSDG 12: Responsible Consumption and ProductionSDG 13: Climate Actionased on hedonic scores for aroma, texture, and taste of the yoghurt after 24 hours of fermentation.

Screening of lactic acid bacteria for their potential use as aromatic starters in fermented vegetables

A plastic composite support (PCS) bioreactor was implemented to evaluate the effects on isoflavone deglycosylation in black soymilk fermented by Rhizopus oligosporus NTU 5. Evaluation for the optimal PCS for mycelia immobilisation was conducted, which led to the significant results that the most mycelium weight (0.237 g per PCS, P < 0.05) is held by an S-type PCS; therefore, it was selected for black soymilk fermentation. It was found that the PCS fermentation system without pH control exhibits better efficiency of isoflavone bioconversion (daidzin to daidzein, and genistin to genistein) than the one with pH control at pH 6.5. As for the long-run fermentation, those without pH control indeed accelerate the isoflavone bioconversion by continuously releasing β-glucosidase into soymilk. Deglycosylation can be completed in 8 to 24 h and sustained for at least 34 days as 26 batches. The non-pH-control fermentation system also exhibits the highest total phenolic content (ranged from 0.147 to 0.340 mg GAE mL(-1) sample) when compared to the pH-controlled and suspended ones. Meanwhile, the black soymilk from the 22nd batch with 8 h fermentation demonstrated the highest DPPH radical scavenging effect (54.7%). A repeated-batch PCS fermentation system was established to accelerate the deglycosylation rate of isoflavone in black soymilk. © 2015 Society of Chemical Industry.

Enrichment of two isoflavone aglycones in black soymilk by using spent coffee grounds as an immobiliser for β-glucosidase

Products fermented with lactic acid bacteria based on whole grain flours of red or white sorghum (Sorghum bicolor (L.) Moench) added with malted sorghum flour, or with skim milk (SM) were developed. Composition, protein amino acid profile, total acidity, pH, prebiotic potential, and bio-functional properties after simulation of gastrointestinal digestion were evaluated. In all cases, a pH of 4.5 was obtained in approximately 4.5 h. The products added with SM presented higher acidity. Products made only with sorghum presented higher total dietary fiber, but lower protein content than products with added SM, the last ones having higher lysine content. All products exhibited prebiotic potential, white sorghum being a better ingredient to promote the growth of probiotic bacteria. The addition of malted sorghum or SM significantly increased the bio-functional properties of the products: the sorghum fermented products added with SM presented the highest antioxidant (ABTS•+ inhibition, 4.7 ± 0.2 mM Trolox), antihypertensive (Angiotensin converting enzyme-I inhibition, 57.3 ± 0.5%) and antidiabetogenic (dipeptidyl-peptidase IV inhibition, 31.3 ± 2.1%) activities, while the products added with malted sorghum presented the highest antioxidant (reducing power, 1.6 ± 0.1 mg ascorbic acid equivalent/mL) and antidiabetogenic (α-amylase inhibition, 38.1 ± 0.9%) activities. The fermented whole grain sorghum-based products could be commercially exploited by the food industry to expand the offer of the three high-growth markets: gluten-free products, plant-based products (products without SM), and functional foods. © 2023 Society of Chemical Industry.

In this study, the manufacture of juwet fruit yoghurt was studied with different treatments of adding skim milk and lactic acid bacteria starter. Yogurt is a processed milk product made through bacterial fermentation. Yogurt is known as a good source of protein, calcium, and probiotics, which can support digestive health and the immune system. Juwet fruit has a high antioxidant and vitamin C content so that juwet fruit has interesting potential to be made into yoghurt. Skim milk is used to utilize high lactose and protein so that the growth of lactic acid bacteria can grow optimally. Lactic acid bacteria are used for preservation, providing texture, and adding flavor to yoghurt drinks. The purpose of this study was to determine the addition of skim milk and lactic acid bacteria starter on the physicochemical, microbiological, and organoleptic characteristics of juwet yoghurt. This study used a Completely Randomized Design (CRD) factorial pattern consisting of two factors. Factor 1 addition of skim milk (5%, 7%, 9%). Factor 2 addition of starter (5%, 7%, 9%). Each treatment was repeated three times. The data obtained were analyzed using analysis of variance (ANOVA). If there is a significant difference between treatments, it is continued with the Duncan test (DMRT) and organoleptic test using the Scoring test with 25 trained panelists. The treatment of adding 9% skim milk and 9% starter was the best treatment that produced juwet yoghurt with a protein content of 2.1% ± 0.036, total titratable acid 2.1% ± 0.1, total soluble solids 22.7ºBrix ± 1.53, total lactic acid bacteria 10.5 log CFU/ml ± 0.023, pH 3.7 ± 0.058, antioxidants 34.0% ± 0.117, viscosity 6.8% ± 0.058, Vitamin C 5.8 ± 0.3, and organoleptic tests of color 2.88 (rather like), taste 3.24 (rather like), aroma 2.68 (rather like), texture 3.76 (like).

Hydrolysis of isoflavone glycosides by Bacillus subtilis natto NTU-18 in black soymilk is reported. At the concentration of 3-5% (w/v), black soymilk in flask cultures, the isoflavones, daidzin, and genistin were highly deglycosylated within 24 h. Deglycosylation of isoflavones was further carried out in a 7-l fermenter with 5% black soymilk. During the fermentation, viable cells increased from 10(3) to 10(9) CFU ml(-1) in 15 h, and the activity of beta-glucosidase appeared at 8 h after inoculation and reached a maximum (3.3 U/ml) at 12 h, then decreased rapidly. Deglycosylation of isoflavone glycosides was observed at the same period, the deglycosylation rate of daidzin and genistin at 24 h was 100 and 75%, respectively. It is significantly higher than the previous reports of fermentation with lactic acid bacteria. In accordance with the deglycosylation of isoflavone glycosides, the estrogenic activity of the 24 h fermented black soymilk for ERbeta estrogen receptor increased to threefold; meanwhile, the fermented broth activated ERalpha estrogen receptor to a less extent than ERbeta. These results suggest that this fermentation effectively hydrolyzed the glycosides from isoflavone in black soymilk and the fermented black soymilk has the potential to be applied to selective estrogen receptor modulator products.

Lactic acid bacteria are a group of bacteria capable of producing lactic acid, H2O2, diacetyl and bacteriocins. Isolation purpose of lactic acid bacteria is to produce antimicrobial that will be used to inhibit the growth of pathogenic bacteria in the digestive tract. The study was conducted to isolate indigenous lactic acid bacteria from health broiler intestine and to investigate the ability to inhibit the growth of Salmonella sp. This study used 144 DOC (Day Old Chicken) final stock “Arbor acres CP 707”. Lactic acid bacteria 109 cell · mL–1 administered through drinking water daily and twice per week for 5 wk. The research results showed that the potential as indigenous lactic acid bacteria were Lactobacillus spp., Streptococcus spp., and Bifidobacterium bifidum. The administration of lactic acid bacteria with a frequency of daily was effective to decrease the population of Salmonella sp. in the intestines of broiler chickens.

This study explores microbial selenization as a strategy for delivering selenium (Se) and seleno-nanoparticles (SeNPs) in a mango and passion fruit juice fermented by indigenous lactic acid bacteria (LAB). The fruit juice was fermented by a mixed culture of Se-enriched cells of Fructobacillus tropaeoli CRL2034 and Lactiplantibacillus paraplantarum CRL2051 at 30°C for 24h. The fermented beverages' intracellular Se and SeNPs content, antioxidant activity, microbial ability to survive gastrointestinal conditions, and sensory properties were evaluated. The mixed starter culture grew 2.04 ± 0.17 log CFU/mL in the fruit juice after 24h and produced lactic acid, acetic acid, and mannitol. After gastrointestinal digestion, the fermented juice exhibited high antioxidant activity (14.20 ± 0.19µM TE/mL) and a good survival rate (8.29 ± 0.06 log CFU/mL). The SeNPs were detected after digestion by scanning electron microscopy. The fermented and non-fermented juices were accepted by the consumers indiscriminately and their consumption intention was similar (41.7% and 32.5%, respectively). The juices had a sensory shelf life of 30days. An increase in the Se concentration (from 20.64 to 68.27µg Se/L, P < 0.05) in the fermented juice using selenized cells was observed. This beverage provides 40% of the recommended daily Se intake in a 200mL serving. Combining Se and fermentation by rationally selected LAB offers a promising strategy for enhancing fruit-based beverages' nutritional value and stability. This fermented juice could be used as a dietary supplement of Se, and as a vehicle to deliver potentially probiotic bacteria.