Dietary intake of yacon roots (Smallanthus sonchifolius) affects gut microbiota and fecal mucin and prevents intestinal inflammation in mice.

Consumption of yacon (Smallanthus sonchifolius) is associated with beneficial effects such as prevention of metabolic diseases. Yacon root is known to contain various bioactive components including indigestible carbohydrates, but the alteration of intestinal environment after treatment with yacon has not been fully investigated. This study investigated yacon-containing diet effects on the intestinal environment in mice, including microbial composition, short-chain fatty acid levels, and mucus content. After mice were administered yacon-containing diet for 4 weeks, 16S rRNA gene sequencing analyses revealed their fecal microbiota profiles. Organic acid concentrations in cecal contents were measured using an HPLC system. Compared to the control group, yacon-containing diet-received mice had significantly higher the concentrations of succinic acid, lactic acid, acetic acid, and propionic acid. The fecal mucin content was also higher in yacon-containing diet-received mice. Results of 16S rRNA gene sequencing analyses showed that the relative abundances of 27 taxa differed significantly in yacon-containing diet-received mice. Furthermore, results show effects of yacon administration on intestinal inflammation using 2,4,6-trinitrobenzene sulfonic acid induced colitis model in mice. Increased colonic damage and myeloperoxidase activity after 2,4,6-trinitrobenzene sulfonic acid treatment were suppressed in yacon-containing diet-received mice. Results suggest that oral intake of yacon root modulates the intestinal environment, thereby inhibiting intestinal inflammation.

Changes in Microbiota During Multiple Fermentation of Kefir in Different Sugar Solutions Revealed by High-Throughput Sequencing.

Kefir is a fermented beverage produced through the activity of its grains, which is constituted by lactic acid and acetic acid bacteria and yeasts. We studied the bacterial succession during multiple fermentation of Argentinian kefir in brown sugar, purified molasses or high-test molasses, using 16S high-throughput sequencing. Firmicutes was dominant (up to 98% of total population) in grains and beverages made from various sugar substrates, except in high-test molasses beverage, which was dominated by Proteobacteria (up to 78% of total population). Major bacterial species in Firmicutes were Liquorilactobacillus nagelii, Lentilactobacillus hilgardii/diolivorans and Lacticaseibacillus casei/paracasei, which are active in lactic acid fermentation. Proteobacteria comprised Acetobacter lovaniensis and Gluconobacter oxydans/roseus as major species, which are presumably responsible for the acetic acid formation in sugary kefir beverages. Bacteria differ in abundance depending on the sugar type, as revealed by the competitive dominances between L. nagelii and A. loveniensis. Purified molasses led to scarce acetic acid bacteria during fermentation, indicating that it is not a suitable substrate for their growth. Our results suggest that acetic acid (and/or ethanol) in sugary kefir modulates the succession and dominance of specific lactic acid bacteria. This study will provide valuable information for designing more sophisticated non-dairy fermented beverages with stable microbial properties.

Juice of Citrullus lanatus var. citroides (wild watermelon) inhibits the entry and propagation of influenza viruses in vitro and in vivo.

Vaccines and various anti-influenza drugs are clinically used to prevent and treat influenza infections. However, with the antigenic mismatch of vaccines and the emergence of drug-resistant viral strains, new approaches for treating influenza are warranted. This study focused on natural foods as potential candidates for the development of new treatment options for influenza infections. The screening of plants from the Cucurbitaceae family revealed that the juice of Citrullus lanatus var. citroides (wild watermelon) had the strongest ability to inhibit the replication of influenza virus in Madin-Darby canine kidney cells. The results of a time-of-addition assay indicated that wild watermelon juice (WWMJ) inhibits the adsorption and late stages of viral replication, suggesting that WWMJ contains multiple constituents with effective anti-influenza activity. A viral adsorption analysis showed that WWMJ reduces the amount of viral RNA in the cells at 37°C but not at 4°C, confirming that WWMJ inhibits viral entry into the host cells at 37°C. These results suggest that a mechanism other than the inhibition of viral attachment is involved in the anti-influenza action of WWMJ, which is perhaps responsible for a reduction in internalization of the virus. Administration of WWMJ into the nasal mucosa of BALB/c mice infected with the A/PR/8/34 mouse-adapted influenza virus was seen to significantly improve the survival rate. The findings of this study, therefore, demonstrate the anti-influenza potential of WWMJ in vitro and in vivo, thereby suggesting the candidature of WWMJ as a functional food product that can be used to develop anti-influenza agents and drugs.

Development of a Multifunction Set Yogurt Using Rubus suavissimus S. Lee (Chinese Sweet Tea) Extract.

Rubus suavissimus S. Lee leaves, also known as Chinese sweet tea or Tiancha, are used in folk medicine in southern China. This study evaluated the impact of the addition of Chinese sweet tea extract (0.25%, 0.5%, and 1%) on the chemical composition, organoleptic properties, yogurt culture viability, and biological activities (i.e., antioxidant, anticancer, and antihypertensive activities) of yogurt. Seven phenolic compounds were reported in Chinese sweet tea for the first time. The numbers of the yogurt culture were similar across all yogurt treatments. The yogurt supernatant with 0.25%, 0.5%, and 1% Chinese sweet tea extract had a total phenolic content that was 3.6-, 6.1-, and 11.2-fold higher, respectively, than that of the control yogurt. The biological activities were significantly increased by the addition of Chinese sweet tea extract: Yogurt with the addition of 1% Chinese sweet tea extract had the highest biological activities in terms of the antioxidant activity (92.43%), antihypertensive activity (82.03%), and inhibition of the Caco-2 cell line (67.46%). Yogurt with the addition of 0.5% Chinese sweet tea extract received the highest aroma and overall acceptability scores. Overall, Chinese sweet tea extract is a promising food ingredient for producing functional yogurt products that may substantially contribute to reducing the risk of developing chronic diseases such as cancer and cardiovascular disease.

Improving the Functional Activities of Curcumin Using Milk Proteins as Nanocarriers.

Curcumin is one of the most common spices worldwide. It has potential benefits, but its poor solubility and bioavailability have restricted its application. To overcome these problems, this study aimed to assess the efficacy of sodium caseinate (SC), α-lactalbumin (α-La), ß-lactoglobulin (ß-lg), whey protein concentrate (WPC) and whey protein isolate (WPI) as nanocarriers of curcumin. Furthermore, the antioxidant, anticancer and antimicrobial activities of the formed nanoparticles were examined. The physicochemical characteristics of the formed nanoparticles as well as the entrapment efficiency (%) and the in vitro behavior regarding the release of curcumin (%) were examined. The results showed that the formation of curcumin-milk protein nanoparticles enhanced both the entrapment efficiency and the in vitro behavior release of curcumin (%). Cur/ß-lg nanoparticles had the highest antioxidant activity, while SC and WPC nanoparticles had the highest anticancer effect. The antimicrobial activity of the formed nanoparticles was much higher compared to curcumin and the native milk proteins.

Chemical, Microbiological, and Functional Characterization of Kefir Produced from Cow's Milk and Soy Milk.

Kefir is a functional beverage that contains lactic and acetic acid bacteria (LAB, AAB) and yeasts. This work's aim was to study the chemical, microbial, and functional characteristics of kefir produced from cow's milk and soy milk. After fermentation, free amino acids were 20.92 mg 100 mL-1 and 36.20 mg 100 mL-1 for cow's milk and soy milk kefir, respectively. Glutamic acid was majority in both, suggesting that microbial proteolysis leads to an increase in free amino acids including glutamic acid. 108-109 CFU mL-1 LAB, 106-107 CFU mL-1 AAB, and 106-107 CFU mL-1 yeasts were counted in cow's milk kefir, whereas soy milk kefir contained greatly lower yeasts and AAB. Lactococcus lactis, Kazachstania unispora, and Saccharomyces cerevisiae were isolated as major microorganisms in both kefirs. Acetobacter orientalis only existed in cow's milk kefir. Cow's milk and soy milk showed ACE inhibitory activity, which significantly increased after fermentation. Both kefirs also exhibited antioxidant activity and bactericidal activity against Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus.

Characterization of physicochemical and digestive properties of starches from various "dainagon" adzuki beans (Vigna angularis) cultivated in Japan.

We investigated the physicochemical properties of starches extracted from Vigna angularis variants Noto-dainagon, Kyoto-dainagon, dainagon, and erimo-type adzuki beans. The particle size was larger in the Noto-dainagon starch than in the other starches, but all starches displayed a C-type crystal structure in the X-ray diffraction analysis. The onset and peak temperatures of gelatinization were approximately 7 °C lower in the Noto-dainagon and Kyoto-dainagon starches than in the dainagon and adzuki bean starches. The dainagon and adzuki bean starches also demonstrated lower swelling power at 60 °C than the other starches. The rapid visco-analyser curves of all starches showed no breakdown during the heating process, and the final viscosities of the starches increased with decreasing temperature. The apparent amylose and phosphorus contents were highest in the Noto-dainagon starch (36.6% and 95.6 ppm, respectively). The branched- chain length degree of polymerization 6-12 was lowest in the adzuki bean starch. In vitro and in vivo analyses of the digestive properties indicated that dainagon starch was more indigestible than the other starches. We considered that dainagon starch was a potentially viable health-promoting ingredient.

Bioactive properties of probiotic set-yogurt supplemented with Siraitia grosvenorii fruit extract.

Siraitia grosvenorii fruit (SGF) has been used as a natural sweetener and traditional medicine in China for more than two centuries. This study evaluated the effect of SGF extract supplementation (0.5%, 1%, and 2%) on the chemical, microbial and sensory properties of probiotic yogurt. The antioxidant, angiotensin-converting-enzyme inhibitory (ACE-I) and antibacterial bioactivities were determined. SGF extract supplementation improved some of the chemical and physicochemical characteristics. Probiotic yogurt with the fruit extract had significantly more Lactobacillus casei and Lactobacillus bulgaricus, whereas there was no significant effect on the number of Streptococcus thermophiles. The bioactivities were significantly increased by SGF extract supplementation. Probiotic yogurt with 2% SGF extract showed the highest antioxidant, ACE-I, and antibacterial activities, whereas the one with 1% SGF extract conferred the highest sensory attributes score. Overall, SGF extract offers a promising option as a dietary supplement to produce novel dairy products that have high nutritional and bioactivity values.

Anti-Influenza Virus Activity of Adlay Tea Components.

Our previous study showed anti-influenza virus activity in adlay tea prepared from adlay seeds, naked barley seeds, soybean, and cassia seeds. In this study, we evaluated the anti-influenza virus activity of each component of this tea and analyzed their active ingredients. Each component was roasted and extracted in hot water; the extracts were tested for antiviral activity and their mechanisms of action were studied. All the tea components showed antiviral activity against the H1N1 and H3N2 influenza subtypes and against influenza B. The viral stages inhibited by the components were virus adsorption and replication in proliferative process, suggesting that the action mechanisms of the components might differ from those of oseltamivir acid. Of the tea components, soybean showed the strongest activity. Therefore, we analyzed its active ingredients by liquid chromatography quadruple time-of-flight mass spectrometry (LC/qTOF-MS) and daidzein and glycitein were detected as active ingredients. Here, anti-influenza virus action of glycitein was the first report.

Robust Domination of Lactobacillus sakei in Microbiota During Traditional Japanese Sake Starter Yamahai-Moto Fermentation and the Accompanying Changes in Metabolites.

The successful production of sake (Japanese rice wine) is brought about by drastic changes in microbial flora and chemical components during fermentation. In the traditional manufacturing process of sake starter (yamahai-moto), spontaneous growth of lactic acid bacteria suppresses inappropriate microorganisms and prepares the optimum environment for the alcohol fermentative yeast. In this study, we analyzed the changes in bacterial flora and chemical components of yamahai-moto. High-throughput next-generation sequencing (NGS) of the 16S ribosomal RNA gene V4 region revealed that various kinds of bacteria, including nitrate-reducing bacteria, existed in the early fermentation stage; however, Lactobacillus sakei then increased drastically to become dominant in the middle stage. Interestingly, this result was different from that obtained in the previous year at the same manufacturer; the early-stage major bacterium was Lactobacillus acidipiscis. Lactic acid, glucose, isomaltose, and total free amino acids increased throughout the fermentation process, which was attributable to the metabolism of L. sakei and the koji mold. It is noteworthy that significant ornithine accumulation and arginine consumption were observed from the middle to late stages. Thirty-eight percent of the L. sakei isolates from yamahai-moto exhibited significant ornithine production, indicating that the arginine deiminase pathway of L. sakei was working to survive the extremely low pH environment of the moto after the middle stage. This is the first report that includes concurrent analyses of the NGS-based bacterial flora and chemical components of yamahai-moto, providing further knowledge to help understand and improve the process of sake brewing.

Inhibition of influenza virus replication by adlay tea.

BACKGROUND: The present study was conducted aiming to examine the antiviral activity of adlay tea and its components against influenza viruses. We further aimed to clarify the mechanism by which these components regulate virus replication. RESULTS: Adlay tea at a concentration suitable for drinking inhibited the multiplication of influenza viruses. Moreover, our results suggest that individual components of the tea had antiviral activities against the influenza A/PR/8/34 virus. Adlay tea inhibited multiplication of the H1N1, H3N2 and B types of influenza virus, including oseltamivir-resistant viruses. In addition, adlay tea inhibited influenza infection during the periods of virus adsorption to the cell and virus replication. Adlay tea did not suppress hemagglutination inhibition or cell fusion, although it slightly inhibited virus binding to Malin Darby canine kidney cells. Furthermore, our findings suggest that the antiviral compounds included in adlay tea were ingredients other than polyphenols and that there were several types of effective compounds in adlay tea inhibiting several steps of viral replication. CONCLUSION: The results of the present study demonstrate that adlay tea had antiviral effects against influenza viruses. Our findings with respect to adlay tea suggest that the polyphenols might have a small influence on its antiviral activity and that other ingredients might have more influence. © 2017 Society of Chemical Industry.

Characterization of two cryptic plasmids from Kocuria palustris IPUFS-1 and construction of novel Escherichia coli-Kocuria shuttle vector for biocatalysis.

Two cryptic plasmids, designated pKPAL1 and pKPAL2, were identified from the gram-positive bacterium Kocuria palustris IPUFS-1, which was isolated from a fish source. The 2251-bp and 2488-bp circular genomes of pKPAL1 and pKPAL2, respectively, were sequenced. Subsequent open reading frame (ORF) and homology search analyses suggested that pKPAL1 and pKPAL2 possess two and three ORFs, respectively, and encode the putative replication proteins, RepA and RepB, like the genomes of several plasmids in gram-positive bacteria. Thus, pKPAL1 and pKPAL2 were inferred to belong to the ColE2 plasmid family. We constructed novel Escherichia coli-Kocuria shuttle vectors pKITE101-103 based on pKPAL1. The constructed shuttle vector was stably maintained in Kocuria transformant cells, and vector copy number was estimated to be about 60 per cell. Leifsonia sp. S749 alcohol dehydrogenase (LSADH) was efficiently expressed in Kocuria rhizophila DC2201 using the pKITE103P vector under the control of the promoter of glyceraldehyde 3-phosphate dehydrogenase (gapdh). Herein, we demonstrate that the novel shuttle vector is a useful tool for developing biocatalysts based on organic solvent-tolerant Kocuria cells.

Characterisation of odorants in roasted stem tea using gas chromatography-mass spectrometry and gas chromatography-olfactometry analysis.

Roasted stem tea has a characteristic flavour, which is obtained by roasting tea stems, by-product of green tea production. This research aims to understand the characteristic odorants in roasted stem tea by comparing it to roasted leaf tea. We revealed potent odorants in commercial roasted stem tea using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry with aroma extract dilution analysis (AEDA). The difference between roasted stem and leaf tea derived from the same tea plants were investigated using GC-MS. Pyrazine compounds exhibited a roasted odour and high flavour dilution (FD) factors, as determined via AEDA. Roasted stem tea was richer in these pyrazines than roasted leaf tea. Geraniol and linalool exhibited high FD factors and a floral odour, and roasted stem tea was richer in these compounds than roasted leaf tea. These results may have a positive impact on the development of tea products.

Tracing microbiota changes in yamahai-moto, the traditional Japanese sake starter.

Sake is made from steamed rice, malted rice, and water. Sake production begins with the preparation of a small-scale starter (moto); the quality of moto significantly influences the flavor and richness of sake. In the traditional starter, yamahai-moto, the growth of naturally occurring lactic acid bacteria represses the putrefactive micro-organisms, whereas in the modern starter, sokujo-moto, this is achieved by adding lactic acid. In this study, the successive change in bacterial flora of yamahai-moto was analyzed by pyrosequencing 16S ribosomal RNA genes. Lactobacillus was dominant throughout the process (93-98%). Nitrate-reducing bacteria that have been generally assumed to be the first colonizers of yamahai-moto were scarcely found in the early stage, but Lactobacillus acidipiscis dominated. Lactobacillus sakei drastically increased in the middle stage. This is the first report, though one case study, to show how the early stage microbiota in Japanese yamahai-moto is varyingly controlled without nitrate-reducing bacteria using next-generation sequencing.

The γ-aminobutyric acid-producing ability under low pH conditions of lactic acid bacteria isolated from traditional fermented foods of Ishikawa Prefecture, Japan, with a strong ability to produce ACE-inhibitory peptides.

Many traditional fermented products are onsumed in Ishikawa Prefecture, Japan, such as kaburazushi, narezushi, konkazuke, and ishiru. Various kinds of lactic acid bacteria (LAB) are associated with their fermentation, however, characterization of LAB has not yet been elucidated in detail. In this study, we evaluated 53 isolates of LAB from various traditional fermented foods by taxonomic classification at the species level by analyzing the 16S ribosomal RNA gene (rDNA) sequences and carbohydrate assimilation abilities. We screened isolates that exhibited high angiotensin-converting enzyme (ACE) inhibitory activities in skim milk or soy protein media and produced high γ-aminobutyric acid (GABA) concentrations in culture supernatants when grown in de Man Rogosa Sharpe broth in the presence of 1% (w/v) glutamic acid. The results revealed that 10 isolates, i.e., Lactobacillus buchneri (2 isolates), Lactobacillus brevis (6 isolates), and Weissella hellenica (2 isolates) had a high GABA-producing ability of >500 mg/100 ml after 72 h of incubation at 35 °C. The ACE inhibitory activity of the whey cultured with milk protein by using L. brevis (3 isolates), L. buchneri (2 isolates), and W. hellenica (2 isolates) was stronger than that of all whey cultured with soy protein media, and these IC50 were < 1 mg protein/ml. Three of 10 isolates had high GABA-producing activities at pH 3, suggesting that they could be powerful candidates for use in the fermentation of food materials having low pH.

Removal of cadmium from fish sauce using chelate resin.

Fish sauce that is prepared from squid organs contains cadmium (Cd), which may be present at hazardous concentrations. Cd molecules are predominantly protein bound in freshly manufactured fish sauce, but are present in a liberated form in air-exposed fish sauce. In the present study, we developed a new method for removing both Cd forms from fish sauce using chelate resin and a previously reported tannin treatment. Sixteen-fold decreases in Cd concentrations were observed (0.78-0.05 mg/100 mL) following the removal of liberated Cd using chelate resin treatment, and the removal of protein-bound Cd using tannin treatment. Major nutritional components of fish sauce were maintained, including free amino acids and peptides, and angiotensin I-converting enzyme inhibitory and antioxidant activities.

Microbial and chemical properties of Cambodian traditional fermented fish products.

BACKGROUND: Fermented fish products, commonly consumed in south-east Asia, are used as condiments that contribute to people's nutritional sources and as seasonings to improve food taste and flavour. Among these, the Cambodian products prahok (fish paste), kapi (shrimp paste) and toeuk trey (fish sauce) have not been examined in detail. This is the first study to investigate their chemical and microbial properties. RESULTS: Acetic acid was the most common organic acid with the highest concentration in 10/13 samples (1.9-26.6 g kg(-1)). Lactic acid was also found at high concentrations (0.4-12.9 g kg(-1)). 16S ribosomal RNA gene-dependent phylogenetic analyses indicated that Gram-positive cocci and rods, such as Bacillus, Clostridium, Staphylococcus and Tetragenococcus, were the major microbial populations. High sodium chloride concentrations detected in these products (170-270 g kg(-1)) could be responsible for inhibition of the growth of Gram-negative putrefactive microorganisms. CONCLUSION: This study established a relationship between the chemical and microbial compositions of Cambodian fermented fish products, which provides a basis for preservation and maturation. These data could be beneficial in the manufacturing of these products in terms of microbial control and quality stabilisation.

Pyrosequencing analysis of microbiota in Kaburazushi, a traditional medieval sushi in Japan.

The processing of archetypal Japanese sushi involves microbial fermentation. The traditional sushi kaburazushi, introduced in the middle ages, is made by fermenting salted yellow tail, salted turnip, and malted rice, and is distinguished from the ancient sushi narezushi, made from fish and boiled rice. In this study, we examined changes in the microbial population during kaburazushi fermentation by pyrosequencing the 16S ribosomal RNA genes (rDNA) of the organisms in the fermentation medium. Ribosomal Database Project Classifier analysis identified 31 genera, among which Lactobacillus drastically increased during fermentation (150-fold increment over 8 d), while the relative populations of the other gram-positive bacteria (Staphylococcus and Bacillus) decreased. Basic Local Alignment Search Tool analysis revealed the dominant species to be L. sakei. This organism constituted approximately 90% of Lactobacillus and 79% of total microbiota. The taxonomic diversity and species richness (assayed by Shannon-Weiner Index and Chao 1, respectively) were not significantly different between middle-ages kaburazushi and ancient narezushi. Both types were characterized by the preferential growth of Lactobacillales.

Quantification of major royal jelly protein 1 in fresh royal jelly by indirect enzyme-linked immunosorbent assay.

Rabbit polyclonal antibody produced by a major royal jelly protein 1 (MRJP1) specific peptide reacted only with a MRJP1. Indirect ELISA with the antibody revealed a MRJP1 level of 4.12-4.67 g/100 g in different company's royal jelly, which almost agreed with that of a hexametric form of MRJP1 (apisin) measured by high performance liquid chromatography. These results suggest that MRJP1 exists mainly as apisin in royal jelly.

Effective removal of cadmium from fish sauce using tannin.

Fish sauce prepared from squid organs contains cadmium (Cd), which may be present at hazardous concentrations. In this study, we report a new, inexpensive, and acceptable method for removing Cd from fish sauce using tannin, which is an approved food additive in Japan. Decreases in Cd concentrations of 13-fold were observed (0.39-0.03 mg/100 mL) by incorporating the soluble Cd into a precipitate generated by tannin treatment. The total nitrogen content, free amino acid content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and angiotensin I-converting enzyme inhibitory activity of the treated fish sauce were the same as those of the untreated fish sauce.