Stability and expression of K-ras mimotopes in freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder during storage in vacuum packaging.

AIMS: This study aims to evaluate the storage stability of the freeze-dried recombinant L. lactis NZ3900-fermented milk powder expressing K-ras (Kristen rat sarcoma viral oncogene homolog) mimotopes targeting colorectal cancer in vacuum packaging. METHODS AND RESULTS: The freeze-dried L. lactis-fermented milk powder stored in 4-ply retortable polypropylene (RCPP)-polyamide (PA)-aluminium (AL)-polyethylene terephthalate (PET) and aluminium polyethylene (ALPE) were evaluated throughout 49 days of accelerated storage (38°C and 90% relative humidity). The fermented milk powder stored in 4-ply packaging remained above 6 log10 CFU g-1 viability, displayed lower moisture content (6.1%), higher flowability (43° angle of repose), water solubility (62%), and survivability of L. lactis after simulated gastric and intestinal digestion (> 82%) than ALPE packaging after 42 days of accelerated storage. K-ras mimotope expression was detected intracellularly and extracellularly in the freeze-dried L. lactis-fermented milk powder upon storage. CONCLUSIONS: This suggests that fermented milk powder is a suitable food carrier for this live oral vaccine.

Comparative genomic and phenotypic analyses of pathogenic fungi Neoscytalidium dimidiatum and Bipolaris papendorfii isolated from human skin scraping.

Neoscytalidium dimidiatum and Bipolaris species are fungal plant pathogens that have been reported to cause human diseases. Recently, we have isolated numerous N. dimidiatum and Bipolaris species from the skin scrapings and nails of different patients. In this work, we have sequenced the genome of one strain of N. dimidiatum. The sequenced genome was compared to that of a previously reported Bipolaris papendorfii genome for a better understanding of their complex lifestyle and broad host-range pathogenicity. Both N. dimidiatum UM 880 (~ 43 Mb) and B. papendorfii UM 226 (~ 33 Mb) genomes include 11,015-12,320 putative coding DNA sequences, of which 0.51-2.49% are predicted transposable elements. Analysis of secondary metabolism gene clusters revealed several genes involved in melanin biosynthesis and iron uptake. The arsenal of CAZymes related to plants pathogenicity is comparable between the species, including genes involved in hemicellulose and pectin decomposition. Several important gene encoding keratinolytic peptidases were identified in N. dimidiatum and B. papendorfii, reflecting their potential pathogenic role in causing skin and nail infections. In this study, additional information on the metabolic features of these two species, such as nutritional profiling, pH tolerance, and osmotolerant, are revealed. The genomic characterization of N. dimidiatum and B. papendorfii provides the basis for the future functional studies to gain further insights as to what makes these fungi persist in plants and why they are pathogenic to humans.

Growth characteristic of probiotic in fermented coconut milk and the antibacterial properties against Streptococcus pyogenes.

This study investigated growth characteristics and antibacterial properties of probiotics in fermented coconut milk (CM) against Streptococcus pyogenes. A total of eight probiotics were screened for their survivability in CM. Antibacterial test against S. pyogenes was carried out on strain with highest growth rate. The survivability of probiotics in CM is strain dependent with S. salivarius ATCC 13419 showing the highest growth rate. Titratable acidity of the CM increased significantly while pH decreased significantly upon 9 h fermentation. The antibacterial properties of CM fermented with S. salivarius ATCC 13419 and K12 against S. pyogenes enhanced by 60.60% and 67.69%, respectively, compared to non-fermented CM. Their ability to metabolise carbohydrates and fats in CM was proven where alpha-glucosidase activity of S. salivarius ATCC 13419 and K12 was 22.42 ± 1.73 and 24.92 ± 7.22 unit/L, respectively, whereas, lipase activity was 1498.29 ± 48.50 and 1749.90 ± 254.28 unit/L, respectively. Lipolytic activity of these strains was further evidenced by GC-MS results whereby lauric acid content (potent antibacterial substance) in CM fermented with S. salivarius ATCC 13419 and K12 increased significantly by 5.03% and 10.74%, respectively. In conclusion, fermented CM provided a new alternative of non-dairy functional product with antibacterial potential against S. pyogenes.

Physicochemical and functional properties of Alcalase-extracted protein hydrolysate from oil palm leaves.

BACKGROUND: The oil palm tree produces 90% of wastes and the limited usage of these wastes causes a major disposal problem in the mills. Nevertheless, these by-products have a large amount of nutritional components. Thus, the present study aimed to determine the physicochemical and functional properties of protein hydrolysates (PH) from oil palm leaves (OPL) extracted using different concentrations of Alcalase (0-10%) at 2 h of hydrolysis time. RESULTS: Fourier transform infrared spectral analyses showed that the enzymatic hydrolysis altered functional groups of OPL where a secondary amine was present in the PH. Changes were also observed in the thermal stability where the enthalpy heat obtained for PH (933.93-1142.57 J g-1 ) was much lower than OPL (7854.11 J g-1 ). The results showed that the PH extracted by 8% Alcalase exhibited absolute zeta potential, as well as a high emulsifying activity index (70.64 m2  g-1 of protein) and emulsion stability index (60.58 min). Furthermore, this PH showed higher solubility (96.32%) and emulsifying properties compared to other PHs. It is also comparable with commercial plant proteins, indicating that 8% Alcalase is an optimum concentration for hydrolysis. CONCLUSION: In summary, the physicochemical and functional properties of PH extracted from OPL showed good functional properties, suggesting that it can be used as an alternative plant protein in food industries. © 2021 Society of Chemical Industry.

Oral probiotic and its delivery carriers to improve oral health: A review.

In recent years, oral probiotics have been researched on their effectiveness in reducing and preventing oral diseases. Oral probiotics could be introduced into the oral cavity to keep the equilibrium of the microbiome. Hence, the delivery carrier for oral probiotics plays an important factor to ensure a high number of oral probiotics were delivered and released into the oral cavity. This review presents a brief overview of oral microbiota and the role of oral probiotics in reducing oral diseases. Moreover, important aspects of the oral probiotic product such as viability, adherence ability, health effects, safety, and delivery site were discussed. Besides that, the importance of utilizing indigenous oral probiotics was also emphasized. Oral probiotics are commonly found in the market in the form of chewing tablets, lozenges, and capsules. Hence, the oral probiotic carriers currently used in the market and research were reviewed. Furthermore, this review introduces new potential oral probiotic delivery carriers such as oral strip, bucco-adhesive gel, and mouthwash. Their effectiveness in delivering oral probiotics for oral health was also explored.

Molecular epidemiology of respiratory viruses among Malaysian Young children with a confirmed respiratory infection during 2014-2015.

BACKGROUND: In many developing countries, acute respiratory tract infections (ARTIs) are the main cause of morbidity and mortality among young children. This study aims to evaluate the molecular epidemiology of respiratory viruses among Malaysian children with confirmed respiratory infections between July 2014 and July 2015. METHODS: A total of 394 nasopharyngeal swabs were collected prospectively from children age 0-5 years old with ARTIs from hospitals in Kuala Lumpur. Respiratory viral panel (RVP) assay was used to identify the viral aetiology of respiratory infections. RESULTS: From a total of 394 samples, the positive detection rate was 79.9% (n=315). A total of 15 types of RNA viruses and a single type of DNA virus were detected. Enterovirus/rhinovirus (n=112, 28.4%), respiratory syncytial virus (RSV) (n=85, 21.6%), adenovirus (n=64, 16.2%), human bocavirus (n=34, 8.6%), and human metapneumovirus (n=29, 7.4%) were the five predominant viruses. Enterovirus/rhinovirus and RSV constituted most of the viral respiratory infections among young children, especially among children less than 1 year old. No coronavirus was detected among children between 3 and 5 years old. Co-infection caused by 2 or 3 respiratory viruses were detected in 52 patients (13.2%). Enterovirus/rhinovirus, adenovirus, and human bocavirus demonstrated pronounced seasonality. The infection rate peaked during mid-year, while the lowest activity occurred during early of the year. CONCLUSIONS: The use of molecular assay as a routine diagnostic in the hospitals can improve the diagnosis and management of respiratory tract infections among children.

Comparison of the Microbiological Quality and Safety between Conventional and Organic Vegetables Sold in Malaysia.

Given the remarkable increase of public interest in organic food products, it is indeed critical to evaluate the microbiological risk associated with consumption of fresh organic produce. Organic farming practices including the use of animal manures may increase the risk of microbiological contamination as manure can act as a vehicle for transmission of foodborne pathogens. This study aimed to determine and compare the microbiological status between organic and conventional fresh produce at the retail level in Malaysia. A total of 152 organic and conventional vegetables were purchased at retail markets in Malaysia. Samples were analyzed for mesophilic aerobic bacteria, yeasts and molds, and total coliforms using conventional microbiological methods. Combination methods of most probable number-multiplex polymerase chain reaction (MPN-mPCR) were used to detect and quantify foodborne pathogens, including Escherichia coli O157:H7, Shiga toxin-producing E. coli (STEC), Listeria monocytogenes, Salmonella Typhimurium, and Salmonella Enteritidis. Results indicated that most types of organic and conventional vegetables possessed similar microbial count (P > 0.05) of mesophilic aerobic bacteria, yeasts and molds, and total coliforms. E. coli O157:H7 and S. Typhimurium were not detected in any sample analyzed in this study. Among the 152 samples tested, only the conventional lettuce and organic carrot were tested positive for STEC and S. Enteritidis, respectively. L. monocytogenes were more frequently detected in both organic (9.1%) and conventional vegetables (2.7%) as compared to E. coli O157:H7, S. Typhimurium, and S. Enteritidis. Overall, no trend was shown that either organically or conventionally grown vegetables have posed greater microbiological risks. These findings indicated that one particular type of farming practices would not affect the microbiological profiles of fresh produce. Therefore, regardless of farming methods, all vegetables should be subjected to appropriate post-harvest handling practices from farm to fork to ensure the quality and safety of the fresh produce.

Identification and characterization of Daldinia eschscholtzii isolated from skin scrapings, nails, and blood.

BACKGROUND: Daldinia eschscholtzii is a filamentous wood-inhabiting endophyte commonly found in woody plants. Here, we report the identification and characterization of nine D. eschscholtzii isolates from skin scrapings, nail clippings, and blood. METHODS: The nine isolates were identified based on colony morphology, light microscopy, and internal transcribed spacer (ITS)-based phylogeny. In vitro antifungal susceptibility of the fungal isolates was evaluated by the Etest to determine the minimum inhibitory concentration (MIC). RESULTS: The nine isolates examined were confirmed as D. eschscholtzii. They exhibited typical features of Daldinia sp. on Sabouraud Dextrose Agar, with white felty colonies and black-gray coloration on the reverse side. Septate hyphae, branching conidiophore with conidiogenous cells budding from its terminus, and nodulisporium-like conidiophores were observed under the microscope. Phylogenetic analysis revealed that the nine isolates were clustered within the D. eschscholtzii species complex. All the isolates exhibited low MICs against azole agents (voriconazole, posaconazole, itraconazole, and ketoconazole), as well as amphotericin B, with MIC of less than 1 µg/ml. DISCUSSION: Early and definitive identification of D. eschscholtzii is vital to reducing misuse of antimicrobial agents. Detailed morphological and molecular characterization as well as antifungal profiling of D. eschscholtzii provide the basis for future studies on its biology, pathogenicity, and medicinal potential.

Isolation and Characterization of an Atypical Metschnikowia sp. Strain from the Skin Scraping of a Dermatitis Patient.

A yeast-like organism was isolated from the skin scraping sample of a stasis dermatitis patient in the Mycology Unit Department of Medical Microbiology, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia. The isolate produced no pigment and was not identifiable using chromogenic agar and API 20C AUX. The fungus was identified as Metschnikowia sp. strain UM 1034, which is close to that of Metschnikowia drosophilae based on ITS- and D1/D2 domain-based phylogenetic analysis. However, the physiology of the strain was not associated to M. drosophilae. This pathogen exhibited low sensitivity to all tested azoles, echinocandins, 5-flucytosine and amphotericin B. This study provided insight into Metschnikowia sp. strain UM 1034 phenotype profiles using a Biolog phenotypic microarray (PM). The isolate utilized 373 nutrients of 760 nutrient sources and could adapt to a broad range of osmotic and pH environments. To our knowledge, this is the first report of the isolation of Metschnikowia non-pulcherrima sp. from skin scraping, revealing this rare yeast species as a potential human pathogen that may be misidentified as Candida sp. using conventional methods. Metschnikowia sp. strain UM 1034 can survive in flexible and diverse environments with a generalist lifestyle.

Probiotics and the BSH-related cholesterol lowering mechanism: a Jekyll and Hyde scenario.

Probiotic microorganisms have been documented over the past two decades to play a role in cholesterol-lowering properties via various clinical trials. Several mechanisms have also been proposed and the ability of these microorganisms to deconjugate bile via production of bile salt hydrolase (BSH) has been widely associated with their cholesterol lowering potentials in prevention of hypercholesterolemia. Deconjugated bile salts are more hydrophobic than their conjugated counterparts, thus are less reabsorbed through the intestines resulting in higher excretion into the feces. Replacement of new bile salts from cholesterol as a precursor subsequently leads to decreased serum cholesterol levels. However, some controversies have risen attributed to the activities of deconjugated bile acids that repress the synthesis of bile acids from cholesterol. Deconjugated bile acids have higher binding affinity towards some orphan nuclear receptors namely the farsenoid X receptor (FXR), leading to a suppressed transcription of the enzyme cholesterol 7-alpha hydroxylase (7AH), which is responsible in bile acid synthesis from cholesterol. This notion was further corroborated by our current docking data, which indicated that deconjugated bile acids have higher propensities to bind with the FXR receptor as compared to conjugated bile acids. Bile acids-activated FXR also induces transcription of the IBABP gene, leading to enhanced recycling of bile acids from the intestine back to the liver, which subsequently reduces the need for new bile formation from cholesterol. Possible detrimental effects due to increased deconjugation of bile salts such as malabsorption of lipids, colon carcinogenesis, gallstones formation and altered gut microbial populations, which contribute to other varying gut diseases, were also included in this review. Our current findings and review substantiate the need to look beyond BSH deconjugation as a single factor/mechanism in strain selection for hypercholesterolemia, and/or as a sole mean to justify a cholesterol-lowering property of probiotic strains.

Effect of electroporation on bioconversion of isoflavones and probiotic properties of parents and subsequent passages of Bifidobacterium longum.

This study aimed to evaluate the effects of electroporation on growth, bioconversion of isoflavones, and probiotic properties of parent organisms and subsequent passages of Bifidobacterium longum FTDC 8643. Electroporation with the strength of electric field at 7.5 kV cm(-1) for 3.5 ms was applied on B. longum FTDC 8643. The viability of B. longum FTDC 8643 increased significantly upon treatment with electroporation. Such treatment also enhanced the intracellular and extracellular ß-glucosidase activity, leading to enhanced production of bioactive isoflavone aglycones in mannitol-soymilk (P < 0.05). In addition, these treated cells also exhibited better tolerance toward acidic (pH 2 and pH 3) and intestinal bile salt condition compared to the control (P < 0.05). The electroporated cell also possessed better adhesion ability and antimicrobial activity (P < 0.05). However, all these positive effects were only prevalent in the parent cells and were not observed in their subsequent passages of electroporated cells. Our results suggested that electroporation could enhance the bioactive and probiotic potentials of parent cells of B. longum FTDC 8643 and could be used in the production of probiotic foods with enhanced bioactivity.

Hypolipidemic effect of Goami-3 rice (Oryza sativa L. cv. Goami-3) on C57BL/6J mice is mediated by the regulation of peroxisome proliferator-activated receptor-α and -γ.

We investigated the hypolipidemic effects of Goami-3 rice (GR; Oryza sativa L. cv. Goami-3), a newly developed strain with high levels of amylose and fibers. Diet-induced obese mice were fed three types of isocaloric diets for 8 weeks: a high-fat diet, a high-fat diet with GR or control rice (CR; O. sativa L. cv. Ilpumbyeo). Mice fed GR exhibited a significant reduction in body fat (-23%), total cholesterol (-20%) and triglyceride concentrations (-30%) compared to mice fed CR. The mice fed GR showed induction of peroxisome proliferator-activated receptor (PPAR)-α and inhibition of γ expressions in the liver and adipose tissue. The reduced adiposity of mice fed GC was supported by changes in the expression of genes related to lipid accumulation and hydrolysis in adipose tissues and the plasma concentrations of insulin, adiponectin and leptin. Principal components analysis with gas chromatography-time-of-flight mass spectrometry-based metabolomic data revealed that the average level of specific plasma metabolites in the GR group was statistically different from that in the other groups after 4weeks. These metabolites included propionic acid, valine, leucine and proline. Based on partial least-squares analysis, the plasma concentrations of valine were inversely correlated with the high-density lipoprotein (HDL) to non-HDL and HDL to total cholesterol ratios. In conclusion, GR feeding for 8 weeks significantly improved dyslipidemia and adiposity in diet-induced obese mice by regulating gene expression of PPARs and its target genes. Key plasma metabolites (including valine) were significantly altered by the hypolipidemic effects of GR.

Synthesis of a novel series of 2-alkylthio substituted naphthoquinones as potent acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors.

We report a new series of naphthoquinone derivatives as potent ACAT inhibitors, which were obtained through structural variations of previously disclosed lead 1. Several analogs represented by 3i-l, 4k-m, 6a-n, 7a, and 7i demonstrated potent human macrophage ACAT inhibitory activity by a cell-based reporter assay with human HepG2 cell lines. In particular, compounds 4l and 6j emerged as highly potent inhibitors, exhibiting significantly high inhibitory potencies with IC50 values of 0.44 µM and 0.6 µM, respectively. Moreover, compound 4l significantly reduced the accumulation of cellular cholesterol in HepG2 cell lines.

Effect of electroporation on viability and bioconversion of isoflavones in mannitol-soymilk fermented by lactobacilli and bifidobacteria.

BACKGROUND: The aim of this study was to evaluate the effect of electroporation (2.5-7.5 kV cm⁻¹ for 3.0-4.0 ms) on the growth of lactobacilli and bifidobacteria, membrane properties and bioconversion of isoflavones in mannitol-soymilk. RESULTS: The viability of lactobacilli and bifidobacteria decreased immediately after electroporation. This was attributed to lipid peroxidation, which led to alterations in the membrane phospholipid bilayer, specifically at the polar head, interface and apolar tail regions. Such alterations also resulted in decreased membrane fluidity and increased membrane permeability upon electroporation (P < 0.05). However, the effect was reversible and treated cells showed better growth than the control upon fermentation for 24 h at 37 °C (P < 0.05). Additionally, electroporation increased the bioconversion of glucosides to bioactive aglycones in mannitol-soymilk, which was attributed to increased intracellular and extracellular ß-glucosidase activities of cells upon treatment (P < 0.05). CONCLUSION: Application of electroporation on lactobacilli and bifidobacteria could be beneficial for the development of fermented soymilk with enhanced bioactivity. Considering the enhanced bioactive aglycones, this soymilk could be useful for the prevention of hormone-dependent disorders.

Induction of ABCA1 and ABCG1 expression by the liver X receptor modulator cineole in macrophages.

We investigated the effect of cineole on the expression of genes related to reverse cholesterol transport and hepatic fatty acid metabolism. Cineole, a small aroma compound in teas and herbs, significantly stimulated the transactivation of liver X receptor modulator (LXR)-α and LXR-ß. The mRNA and protein expression of LXRs and their target genes, including ABCA1 and ABCG1, was significantly increased in macrophages stimulated with cineole. This led to the subsequent removal of cholesterol from the cells. Interestingly, cineole showed tissue-selective LXR induction: hepatocytes stimulated with cineole showed significantly reduced expression of LXR-α and LXR-α-responsive genes, including FAS and SCD-1 (P <0.05). Accordingly, hepatocytes treated with cineole displayed reduced cellular lipid accumulation compared with control cells, as assessed by Oil Red O lipid staining and cholesterol quantification. These results suggest that cineole is a selective LXR modulator that regulates the expression of key genes in reverse cholesterol transport in macrophages without inducing lipogenesis in hepatocytes. This selective LXR modulator may have practical implications for the development of hypocholesterolemic or anti-atherosclerotic agents and also suggests.

Growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of Lactobacillus upon ultraviolet radiation.

The objective of this study was to evaluate the effects of ultraviolet (UV) radiation (UVB; 90 J/m²) on growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of L. casei FTDC 2113. UV radiation significantly enhanced (P < 0.05) the growth of parent cells in mannitol-soymilk fermented at 37°C for 24 h. This had led to an enhanced intracellular and extracellular ß-glucosidase activity with a subsequent increase in bioconversion of isoflavones in mannitol-soymilk (P < 0.05). UV radiation also promoted (P < 0.05) the tolerance of parent cells towards acidic condition (pH 2 and 3) and intestinal bile salts (oxgall, taurocholic and cholic acid). In addition, parent treated cells also exhibited better (P < 0.05) adhesion ability to mucin and antimicrobial activity compared to that of the control. All these positive effects of UV radiation were only prevalent in the parent cells without inheritance by first, second and third passage of cells. Although temporary, our results suggested that UV radiation could enhance the bioactive and probiotic potentials of L. casei FTDC 2113, and thus could be applied for the production of probiotic products with enhanced bioactivity.

Enhanced growth and bioconversion of isoflavones in prebiotic-soymilk fermented by UV-treated lactobacilli and bifidobacteria.

The aim of this study was to evaluate the effects of ultraviolet (UV) radiation (ultraviolet A (UVA), ultraviolet B (UVB) and ultraviolet C (UVC) at 30-90 J/m²) on the membrane properties of lactobacilli and bifidobacteria, and their bioconversion of isoflavones in prebiotic-soymilk. UV treatment caused membrane permeabilization and alteration at the acyl chain, polar head and interface region of membrane bilayers via lipid peroxidation. Such alteration subsequently led to decreased (p < 0.05) viability of lactobacilli and bifidobacteria immediately after the treatment. However, the effect was transient where cells treated with UV, particularly UVA, grew better in prebiotic-soymilk than the control upon fermentation at 37°C for 24 h (p < 0.05). In addition, UV treatment also increased (p < 0.05) the intracellular and extracellular ß-glucosidase activity of lactobacilli and bifidobacteria. This was accompanied by an increased (p < 0.05) bioconversion of glucosides to bioactive aglycones in prebiotic-soymilk. Our present study illustrated that treatment of lactobacilli and bifidobacteria with UV could develop a fermented prebiotic-soymilk with enhanced bioactivity.

Effect of ultrasound on the growth of probiotics and bioconversion of isoflavones in prebiotic-supplemented soymilk.

The objective of the present study was to evaluate the effects of ultrasound on the growth of probiotics and bioconversion of isoflavones in prebiotic-soymilk. Previous studies have shown that ultrasound elevated microbial enzymatic activity and growth by altering cellular membranes. The growth of probiotics was significantly decreased (P < 0.05) immediately after ultrasound treatment, attributed to membrane permeabilization, cell lysis, and membrane lipid peroxidation upon ultrasound treatment. The ultrasound treatment also caused alteration at the acyl chain, polar head, and interface region of the probiotic membrane phospholipid bilayers. The cells treated with ultrasound showed recovery from injury with subsequent increase in growth upon fermentation in soymilk (P < 0.05). Ultrasound treatment at 100 W for 2 and 3 min also enhanced (P < 0.05) the intracellular and extracellular ß-glucosidase activity of probiotics, leading to increased (P < 0.05) bioconversion of glucosides to aglycones in the prebiotic-soymilk. Our present study illustrated that ultrasound treatment could produce bioactive synbiotic-soymilk with increased concentrations of bioactive aglycones.

Effect of prebiotics on viability and growth characteristics of probiotics in soymilk.

BACKGROUND: Soy products have attracted much attention lately as carriers for probiotics. This study was aimed at enhancing the growth of probiotics in soymilk via supplementation with prebiotics. RESULTS: Lactobacillus sp. FTDC 2113, Lactobacillus acidophilus FTDC 8033, Lactobacillus acidophilus ATCC 4356, Lactobacillus casei ATCC 393, Bifidobacterium FTDC 8943 and Bifidobacterium longum FTDC 8643 were evaluated for their viability and growth characteristics in prebiotic-supplemented soymilk. In the presence of fructooligosaccharides (FOS), inulin, mannitol, maltodextrin and pectin, all strains showed viability exceeding 7 log(10) colony-forming units mL(-1) after 24 h. Their growth was significantly (P < 0.05) increased on supplementation with maltodextrin, pectin, mannitol and FOS. Additionally, supplementation with FOS, mannitol and maltodextrin increased (P < 0.05) the production of lactic acid. Supplementation with FOS and maltodextrin also increased the alpha-galactosidase activity of probiotics, leading to enhanced hydrolysis and utilisation of soy oligosaccharides. Finally, prebiotic supplementation enhanced the utilisation of simpler sugars such as fructose and glucose in soymilk. CONCLUSION: Supplementation with prebiotics enhances the potential of soymilk as a carrier for probiotics.

Angiotensin I-converting enzyme inhibitory activity and bioconversion of isoflavones by probiotics in soymilk supplemented with prebiotics.

Lactobacillus sp. FTDC 2113, L. acidophilus FTDC 8033, L. acidophilus ATCC 4356, L. casei ATCC 393, Bifidobacterium FTDC 8943 and B. longum FTDC 8643 were incorporated into soymilk supplemented with fructooligosaccharides (FOS), inulin, mannitol, maltodextrin and pectin. The objective of the present study was to evaluate the effects of prebiotics on the bioactivity of probiotic-fermented soymilk. Proteolytic activity was increased in the presence of FOS, while the supplementation of inulin and pectin increased the angiotensin I-converting enzyme inhibitory activity accompanied by lower IC(50) values. The beta-glucosidase activity was also enhanced in the presence of pectin. This led to higher bioconversion of glucosides to aglycones by probiotics, especially genistin and malonyl genistin to genistein. Results from this study indicated that the supplementation of prebiotics enhanced the in-vitro antihypertensive effect and production of bioactive aglycones in probiotic-fermented soymilk. Therefore, this soymilk could potentially be used as a dietary therapy to reduce the risks of hypertension and hormone-dependent diseases such as breast cancer, prostate cancer and osteoporosis.