Bacterial viability, antioxidant stability, antimutagenicity and sensory properties of onion types fermentation by using probiotic starter during storage

Purpose The purpose of this study was to assess the bacterial viability, antioxidative activity, antimutagenicity and sensory evaluation of fermented onion types by using probiotic starters after fermentation at 37 °C for 24 hours and storage in the refrigerator for 28 days. Design/methodology/approach For onion fermentation, Lactobacillus acidophilus (LA-5), Bifidobacterium bifidum (BB-12), and Streptococcus thermophilus (ST) were utilised. This research was conducted on three types of onion: white onion, red onion and scallion. With a 5% brine solution, the onions were sliced into 3-5 cm long and 1-2 cm wide slices. The process of fermentation was achieved by adding 2% (108 CFU/ gm) of fresh probiotic starter and incubating it for 24 hours at 37 °C. The fermented onion samples were kept in the refrigerator for 28 days. After fermentation and storage, the pH and total acidity were estimated, the vitality of probiotic bacteria was evaluated in samples of the onion species. The Gas chromatography-mass spectrometry (GC-MS) technique was used to identify the bioactive components in fermented onion types. The antioxidant activity of fermented onions was measured using the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging activity assay and the hydroxyl radical scavenging activity test. The Ames test was used to detect the antimutagenicity of fermented onion samples. Findings After fermentation, the fermented scallion (p = 0.036) has the highest vitality of all the starter bacteria species. The fermentation of onion types produced a pH of between 4.1–4.7 and 0.19–0.23% total acidity, which is in the range of reduced 3.1–3.5 pH values and 0.42–0.63% total acidity after 28 days. The viability of Lactobacillus acidophilus and Bifidobacterium bifidum in fermented scallions was Log. 7.79 and 7.57 CFU/gm. The GC-MS technique found 14 bioactive compounds in fermented white onions and 13 compounds in fermented white onions, with 15 compounds in scallion fermentation. The majority of these bioactive compounds are strong antioxidants. The antioxidant properties of fermented scallion significantly increased after 28 days of storage time, showing an inhibitory effect on the DPPH assay (p = 0.02) and the scavenging activity of the hydroxyl radical assay (p = 0.01). Sensory evaluation tests revealed that the fermented scallion was a suitable product in terms of appearance, aroma and overall acceptability. Originality/value Commercially accessible probiotic foods account for a sizable portion of the consumer market. Furthermore, as consumer interest in healthy eating grows, so does demand for plant-based goods. All onion types fermented with probiotic bacteria have many chemical compounds that have both antioxidant and carcinogenic activity. The fermented scallion onion sample was significantly superior to the rest of the other types of onions.

A randomised, double-blind, placebo-controlled trial of Bifidobacterium bifidum CCFM16 for manipulation of gut microbiota and relief from chronic constipation

A variety of opinions exist on the potential of probiotics to provide relief from chronic constipation with much focus placed on their mechanism of action and causes of heterogeneity in...

Bifidobacterium bifidum Shows More Diversified Ways of Relieving Non-Alcoholic Fatty Liver Compared with Bifidobacterium adolescentis

The occurrence of non-alcoholic fatty liver disease (NAFLD) is closely related to intestinal microbiota disturbance, and probiotics has become a new strategy to assist in alleviating NAFLD. In order to investigate the effect of Bifidobacterium on NAFLD and the possible pathway, a NAFLD model was established by using a high-fat diet (HFD) for 18 weeks. Fourteen strains of Bifidobacterium were selected (seven Bifidobacterium adolescentis and seven Bifidobacterium bifidum) for intervention. The effects of different bifidobacteria on NAFLD were evaluated from liver cell injury, liver fat deposition, liver inflammatory state and liver histopathology, and were taken as entry points to explore the mitigation approaches of bifidobacteria through energy intake, lipid metabolism, glucose metabolism and intestinal permeability. The results showed that Bifidobacterium exerts species-specific effects on NAFLD. B. bifidum exerted these effects mainly through regulating the intestinal microbiota, increasing the relative abundance of Faecalibaculum and Lactobacillus, decreasing the relative abundance of Tyzzerella, Escherichia-Shigella, Intestinimonas, Osillibacter and Ruminiclostridium, and further increasing the contents of propionic acid and butyric acid, regulating lipid metabolism and intestinal permeability, and ultimately inhibiting liver inflammation and fat accumulation to alleviate NAFLD. B. adolescentis exerted its effects mainly through changing the intestinal microbiota, increasing the content of propionic acid, regulating lipid metabolism and ultimately inhibiting liver inflammation to alleviate NAFLD.

Incorporation of Sukkari Date in Probiotic-Enriched Fermented Camel Milk Improves the Nutritional, Physicochemical, and Organoleptical Characteristics

Camel milk and dates are well-known for their great nutritional and therapeutical benefits. Therefore, the study aimed to combine the benefits of fermented camel milk (FCM) and Sukkari date (SKD) in a naturally sweetened FCM. Six treatments of FCM using ABT-5 cultures with 0, 5, 7.5, 10, 12.5, and 15% SKD were carried out. Chemical, physicochemical, rheological properties were studied, while organoleptical attributes and probiotic strains viability were monitored during cold storage (4 °C) up to 15 days. Results showed that fortification with SKD increased total solids (TS), ash, dietary fiber, and carbohydrate content compared to plain FCM. Water holding capacity (WHC) values increased with low and medium SKD levels then decreased with high SKD levels. Minerals such as K, P, Mg, Zn, Fe, and Cu were significantly increased, while Na was significantly decreased. Increased SKD levels in FCM resulted in significant increases in total phenolic content (TPC), total flavonoids (TF), total flavonols (TFL), and antioxidant activity (AOA). Instrumental color analysis exhibited a significant change in L*, b*, BI, and ∆E due to adding SKD in a dose-dependent manner. The viability of Streptococcus thermophiles, Lactobacillus acidophilus, and Bifidobacterium bifidum was increased by adding low and medium SKD levels, resulting in a higher number than the accepted threshold for a probiotic effect. Adding 10 and 12.5% SKD recorded the best-balanced flavor score at the beginning and after up to 15 days of storage, respectively. Conclusively, the current study revealed that fortification with SKD at 7.5–12.5% improved the nutritional quality without adverse effects on the technological, organoleptic characteristics, and probiotics viability and provided acceptable, nutritious, and healthy benefits to FCM.

Evaluating the Potential of the Defatted By-Product of Aurantiochytrium sp. Industrial Cultivation as a Functional Food

While Aurantiochytrium sp. is an increasingly popular source of polyunsaturated fatty acids (PUFAs), its extraction generates high amounts of waste, including the spent, defatted residue. The composition and bioactivities of this by-product could prove to be a major part of the sustainable valorisation of this organism within the framework of a circular economy. In this study, the defatted biomass of commercial Aurantiochytrium sp. was nutritionally characterised, and its amino acid profile was detailed. Additionally, the antioxidant and prebiotic potentials of an enzymatically digested sample of defatted Aurantiochytrium sp. were evaluated under a set of miniaturised in vitro assays. The nutritional profile of the spent Aurantiochytrium biomass revealed a protein and dietary-fibre rich product, with values reaching 26.7% and 31.0% for each, respectively. It also held high concentrations of glutamic and aspartic acid, as well as a favourable lysine/arginine ratio of 3.73. The digested samples demonstrated significant Weissela cibaria and Bifidobacterium bifidum growth-enhancing potential. Residual ferric reducing antioxidant power (FRAP) activity was likely attributed to antioxidant amino acids or peptides. The study demonstrated that some of the nutritional and functional potential that reside in the defatted Aurantiochytrium sp. waste encourages additional studies and the development of food supplements employing this resource’s by-products under a biorefinery framework.

Improvement of the Transglycosylation Efficiency of a Lacto-N-Biosidase from Bifidobacterium bifidum by Protein Engineering

The lacto-N-biosidase LnbB from Bifidobacterium bifidum JCM 1254 was engineered to improve its negligible transglycosylation efficiency with the purpose of enzymatically synthesizing lacto-N-tetraose (LNT; Gal-β1,3-GlcNAc-β1,3-Gal-β1,4-Glc) in one enzymatic step. LNT is a prebiotic human milk oligosaccharide in itself and constitutes the structural core of a range of more complex human milk oligosaccharides as well. Thirteen different LnbB variants were expressed and screened for transglycosylation activity by monitoring transglycosylation product formation using lacto-N-biose 1,2-oxazoline as donor substrate and lactose as acceptor substrate. LNT was the major reaction product, yet careful reaction analysis revealed the formation of three additional LNT isomers, which we identified to have a β1,2-linkage, a β1,6-linkage, and a 1,1-linkage, respectively, between lacto-N-biose (Gal-β1,3-GlcNAc) and lactose. Considering both maximal transglycosylation yield and regioselectivity as well as minimal product hydrolysis, the best variant was LnbB W394H, closely followed by W465H and Y419N. A high transglycosylation yield was also obtained with W394F, yet the substitution of W394 and W465 of the subsite −1 hydrophobic platform in the enzyme with His dramatically impaired the undesirable product hydrolysis as compared to substitution with Phe; the effect was most pronounced for W465. Using p-nitrophenyl-β-lacto-N-bioside as donor substrate manifested W394 as an important target position. The optimization of the substrate concentrations confirmed that high initial substrate concentration and high acceptor-to-donor ratio both favor transglycosylation.

Сравнительное изучение антагонистической активности бифидо- и лактосодержащих пробиотиков

Проведен сравнительный анализ антагонистической активности пробиотических препаратов: монокомпонентных — Бифидумбактерин (Bifidobacterium bifidum), Лактобактерин (Lactobacillus plantarum); поликомпонентных пробиотиков — Бифилакт-БИЛС (L. plantarum, L. acidophilus, B. bifidum), Линекс (L. acidophilus, B. infantis, Enterococcus faecium), Бифиформ (B. longum, E. faecium); на основе сорбированных клеток — Бифидумбактерин форте (B. bifidum, сорбированный на активированном угле) и Имбикапс (B. bifidum, сорбированный на гомогенате бурых водорослей) — методом отсроченного антагонизма (в качестве тест-штамма использовали Escherichia coli 157) и экспресс-теста подавления биолюминесценции индикаторного штамма E. coli lum+. Выявлена высокая чувствительность тест-штаммов E. coli 157 и E. coli lum+ к препаратам Лактобактерин, Бифилакт-БИЛС и Имбикапс. Установлено, что экспресс-тест изменения биолюминесценции штамма E. coli lum+ позволяет оценить антагонистическую активность пробиотического препарата в целом, тогда как метод отсроченного антагонизма дает представление о потенциальных антагонистических свойствах штаммов, входящих в состав препаратов, которую они проявляют в благоприятных условиях. В экспресс-тесте также оценивается метаболитная составляющая препарата, которая играет существенную роль в реализации биологической активности пробиотика. Препараты Лактобактерин, Бифилакт-БИЛС и Имбикапс обладают определенным преимуществом по биологической активности в сравнении с аналогичными отечественными и зарубежными пробиотиками.

Effectiveness of two probiotics in preventing necrotising enterocolitis in a cohort of very-low-birth-weight premature new-borns

According to previous research, the incidence of necrotising enterocolitis (NEC) decreases after supplementation with probiotics. However, few studies have considered the equivalence or otherwise of different strains of probiotics in this respect. Accordingly, this prospective observational study was conducted in a cohort of 245 very-low-birth-weight (VLBW) new-borns to assess the prevalence of NEC after supplementation with the probiotic Inforan® (Berna Biotech, Madrid, Spain) 250 mg capsules containing 109 cfu of Lactobacillus acidophilus (ATCC 4356) and 109 cfu of Bifidobacterium bifidum (ATCC 15696); or with Bivos® (Ferring, Madrid, Spain) containing Lacticaseibacillus (formerly Lactobacillus) rhamnnosus (LGG) (ATCC 53103) (109 cfu); or with no probiotic supplementation. Statistical analysis was performed using multivariant regression for the duration of parenteral nutrition, length of neonatal intensive care unit stay, use of oxygen therapy and presence of chorioamnionitis. Of the VLBW new-borns in the study group, 65 received Infloran, 108 received Bivos and 72 received no probiotic. A significant association was observed between a reduced presence of NEC Stage ≥2 and probiotic supplementation. The odds risk (OR) obtained was 0.174 (95% confidence interval (CI): 0.032-0.936) for Infloran and 0.196 (95%CI: 0.053-0.732) for Bivos. Therefore, both probiotics are associated with a lower prevalence of NEC in VLBW new-borns, with no significant differences.

Multitasking in the gut: the X-ray structure of the multidomain BbgIII from Bifidobacterium bifidum offers possible explanations for its alternative functions

β-Galactosidases catalyse the hydrolysis of lactose into galactose and glucose; as an alternative reaction, some β-galactosidases also catalyse the formation of galactooligosaccharides by transglycosylation. Both reactions have industrial importance: lactose hydrolysis is used to produce lactose-free milk, while galactooligosaccharides have been shown to act as prebiotics. For some multi-domain β-galactosidases, the hydrolysis/transglycosylation ratio can be modified by the truncation of carbohydrate-binding modules. Here, an analysis of BbgIII, a multidomain β-galactosidase from Bifidobacterium bifidum, is presented. The X-ray structure has been determined of an intact protein corresponding to a gene construct of eight domains. The use of evolutionary covariance-based predictions made sequence docking in low-resolution areas of the model spectacularly easy, confirming the relevance of this rapidly developing deep-learning-based technique for model building. The structure revealed two alternative orientations of the CBM32 carbohydrate-binding module relative to the GH2 catalytic domain in the six crystallographically independent chains. In one orientation the CBM32 domain covers the entrance to the active site of the enzyme, while in the other orientation the active site is open, suggesting a possible mechanism for switching between the two activities of the enzyme, namely lactose hydrolysis and transgalactosylation. The location of the carbohydrate-binding site of the CBM32 domain on the opposite site of the module to where it comes into contact with the catalytic GH2 domain is consistent with its involvement in adherence to host cells. The role of the CBM32 domain in switching between hydrolysis and transglycosylation modes offers protein-engineering opportunities for selective β-galactosidase modification for industrial purposes in the future.