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This study aimed to investigate the ability of lactic acid bacteria to remove cholesterol in simulated gastric and intestinal fluids. The findings showed that the amount of cholesterol removed was dependent on the biomass, viability, and bacterial strain. Some cholesterol binding was stable and not released during gastrointestinal transit. The presence of cholesterol affected the fatty acid profile of bacterial cells, potentially influencing their metabolism and functioning. However, adding cholesterol did not significantly impact the survival of lactic acid bacteria during gastrointestinal transit. Storage time, passage, and bacterial culture type did not show significant effects on cholesterol content in fermented dairy products. Variations in cell survival were observed among lactic acid bacteria strains in simulated gastric and intestinal fluids, depending on the environment. Higher milk protein content was found to be more protective for bacterial cells during gastrointestinal transit than fat content. Future research should aim to better understand the impact of cholesterol on lactic acid bacteria metabolism and identify potential health benefits.

A method was devised to assess the impact of short-term pollution. It was demonstrated with a natural toothbrush, known as miswak, which is used as chewing stick in Middle-Eastern countries. To this end, miswak sticks collected from one tree were treated differently. One was immediately placed in a ziplock plastic bag whereas the others were driven 180 km away to a market on the side of a busy road. After a few days, one of the unsold sticks was placed in a ziplock bag. Analysis by inductively coupled plasma mass spectrometry following acid digestion revealed that the polluted miswak had significantly higher concentrations of As, Cd, Pb, Fe and Cu than miswak bagged upon collection. The temporal profiles obtained for Cd and As using on-line leaching of ground miswak with artificial gastro-intestinal fluids (saliva, gastric juice and intestinal juice) at 37 °C, which provide information on bio-accessibility, included a double peak, indicating two different sources. Furthermore, plotting the leaching profiles of the elements against each other confirmed two different sources of As, Cd and Pb. The on-line leaching approach thus provides information that cannot be obtained by batch methods. In this example, bagging miswak upon collection would significantly reduce contamination.

In the present study, the effect of B. subtilis (107cfu/gm) supplemented to the basal diet of two groups of New Zealand rabbit of 28 days (n=15/group) on the count of commensal microflora ( Bifidobacteria and Lactobacilli spp.) and some opportunistic pathogens (E. coli and C. perfringens type A) in the rabbit caeci was investigated. Results indicated that the count of Bifidobacteria and Lactobacilli spp. are significantly increased at all intervals (7, 14, 28 and 40 days post supplementation) in the supplemented group compared with non-supplemented group with P< 0.001. On the other hand, there is a significant decrease in the count of E. coli and C. perfringens specially at 40 days post supplementation from (5.8 log 10 cfu ±0.06) to (3.1 log 10 cfu ±0.07) and from (4.8 log 10 cfu ±0.09) to (2.3 log 10 cfu ±0.09) respectively with P< 0.001. B. subtilis proved to be tolerant to the simulated gastric and intestinal juice for one hour (100% tolerance). However, after two hours, the tolerance to the gastric juice decreased to 70%, with no effect of the artificial intestinal juice on the viability of the organism. In vitro, the antimicrobial effect of B. subtilis on C. perfringens type A by well diffusion method showed an inhibition zone of 10 mm. Results of in vitro effect of B. subtilis on C. perfringens count showed that at 103 dilutions of C. perfringens, its count was reduced 2.1×105 to 3×104 after adding B. subtilis, while at dilution of 102, the count was reduced from 2.4×105 to 7×103cfu/ml after adding B. subtilis. It could be concluded that B. subtilis can be used as a probiotic in rabbits ration due to its ability to increase the commensal microflora count beside its antibacterial effect against some opportunistic pathogens.

The interaction between cucurbit[8]uril (Q[8]) and chloramphenicol (CPE) was investigated using single-crystal X-ray diffraction, spectroscopy, isothermal titration calorimetry (ITC) and UV-Vis, NMR and IR spectroscopy. The effects of Q[8] on the stability, in vitro release performance and antibacterial activity of CPE were also studied. The results showed that CPE and Q[8] formed a 1:1 inclusion complex (CPE@Q[8]) with an inclusion constant of 5.4736 × 105 L/mol. The intervention of Q[8] did not affect the stability of CPE, but obviously reduced the release rate of CPE in artificial gastric and intestinal juice; Q[8] has a slow-release effect on CPE. The antibacterial results showed that the minimum inhibitory concentration (MIC) of CPE and CPE@Q[8] toward Escherichia coli (E. coli) was 1.5 × 10–3 and 1.0 × 10–3 mol/L, respectively, and toward Staphylococcus aureus (SA), the MIC was 2.0 × 10–3 mol/L for both CPE and CPE@Q[8]. Therefore, Q[8] enhanced the inhibitory activity of CPE against E. coli.

Microencapsulation is the most common method in improving probiotic survivability against adverse conditions. In this research, resistant starch was incorporated as prebiotic coating material during the microencapsulation of Lactobacillus rhamnosus GG (LGG) in calcium alginate beads coated with xanthan gum. Three types of microcapsules were produced: LGG only, LGG with resistant starch, and LGG with resistant starch and xanthan gum coating. The size and morphology of microcapsules were measured. Furthermore, the viability for free cells and microencapsulated LGG was tested in the simulated gastric juice (SGJ) (pH 2.0, 2 h) and simulated intestinal juice (SIJ) (pH 7.5, 4 h). The results indicated that 2.0 %(w/v) resistant starch and 0.3 %(w/v) xanthan gum had the highest microencapsulation efficiency (MEE). The morphology for microencapsulated LGG was spherical and white. The mean diameter for all 3 types of microcapsules was in between the range of 562.67 to 614.33 μm and xanthan gum-coated microcapsules had the highest MEE of 84.67 %. The addition of resistant starch and xanthan gum had increased the MEE for encapsulated probiotics. Both encapsulated LGG with and without xanthan gum coating had higher survivability than free cells, which indicated the positive role of resistant starch and xanthan gum in promoting the viability of probiotics during gastrointestinal transit. In general, co-extrusion encapsulation and the addition of resistant starch and xanthan gum coating could protect the viable LGG against the harsh human gastrointestinal condition. HIGHLIGHTS Microencapsulation of Lactobacillus rhamnosus GG using co-extrusion technique LGG encapsulated with resistant starch as wall material and xanthan gum coating Xanthan gum coated-LGG microbead displays highest microencapsulation efficiency Xanthan gum coated-LGG microbeads survives simulated gastrointestinal transit Co-extrusion technique had a positive impact on the viability of LGG GRAPHICAL ABSTRACT

AIM This study aimed to investigate the correlation between the level of exopolysaccharide (EPS) biosynthesis and gastrointestinal tolerance of 12 Lactiplantibacillus plantarum strains. METHODS AND RESULTS In this study, the EPS production and survival rate of 12 strains of L. plantarum under gastrointestinal stress were determined. Results showed that the EPS biosynthesis level of L. plantarum in semi-defined medium ranged from 9.84 to 26.05 mg/L. The survival rates of all strains in simulated gastric juice at pH 3.0 ranged from 43.52% to 112.73%. Among them, eight strains were higher than 90%, while only one strain was lower than 50%. The survival rates of all strains in simulated intestinal juice ranged from 50.36% to 125.39%, among which eight strains were higher than 80%. The survival rates of all strains under 0.1% bile salt stress ranged from 3.39% to 109.34%, among which four strains were higher than 80% and three strains were lower than 60%. Besides, the survival rates of all strains under 0.5% bile salt stress ranged from 0.42% to 95.34%. The results indicated that the 12 L. plantarum strains had good tolerance to simulated gastric juice at pH 3.0, simulated intestinal juice and 0.1% bile salt. Notably, it was observed that the survival rates of L. plantarum strains under simulated gastric juice at pH 3.0 and simulated intestinal juice were significantly positively correlated with EPS biosynthesis (p

Lactobacillus rhamnosus GG (LGG) has low resistance to low pH and bile salt in the gastrointestinal juice. In this study, the gel made from whey protein concentrate (WPC) and pullulan (PUL) was used as the wall material to prepare the microencapsulation for LGG protection. The gelation process was optimized and the properties of gel were also determined. The results showed the optimal gel was made from 10% WPC and 8.0% PUL at pH 7.5, which could get the best protective effect; the viable counts of LGG were 6.61 Log CFU/g after exposure to simulated gastric juice (SGJ) and 9.40 Log CFU/g to simulated intestinal juice (SIJ) for 4 h. Sodium dodecyl sulphite polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that the WPC-PUL gel had low solubility in SGJ, but dissolved well in SIJ, which suggested that the gel can protect LGG under SGJ condition and release probiotics in the SIJ. Moreover, when the gel has highest hardness and water-holding capacity, the viable counts of LGG were not the best, suggesting the relationship between the protection and the properties of the gel was non-linear.

The aim of the experiment was to prepare licorice flavonoids nanoparticles (LFNs) by a liquid antisolvent re-crystallization (LAR) method to improve its oral bioavailability. The experimental data suggested that the saturation solubility of LFNs was 25 times of raw licorice flavonoids (LFs), and at 720 min, the dissolution rates of LFNs in artificial intestinal juice and artificial gastric juice were 9.36 times and 11.66 times of raw LFs, respectively. Furthermore, the antioxidant capacity of LFNs was also superior to raw LFs, and the oral bioavailability of echinatin and licochalcone A in the LFNs was 10.63 times and 6.54 times higher than that of raw LF. LFNs had good biosafety for SD rats at dosages up to 800 mg/kg. Overall, the results manifested that LFNs can be helpful to the enhancement of its oral bioavailability and have a promising application value in the field of food and health care.

Efficient microencapsulation of probiotics by most existing methods is limited by low throughput. In this work, Saccharomyces boulardii and Enterococcus faecium were microencapsulated by a method based on emulsion and internal gelation. The growth and survival of microencapsulated microbes under different stressors were investigated using free non-encapsulated ones as a control. The results showed that the prepared micro-beads by emulsion and internal gelation exhibited a spherical and smooth shape, with sizes between 300 and 500 μm. Both S. boulardii and E. faecium grew well and survived better when encapsulated in micro-beads. The survival rates were increased 25% and 40% for microencapsulated S. boulardii and E. faecium respectively when compared with non-encapsulated controls under high temperature and high humidity. The increases of survival rates were 60% for microencapsulated S. boulardii and 25% for E. faecium in simulated gastric juice. And the increases were 15% and 20% respectively when the survival rates of the microencapsulated S. boulardii and E. faecium were determined in simulated intestinal juice. The microencapsulation by emulsion and internal gelation offers an effective way to protect microbes in adverse in vitro and in vivo conditions and is promising for the large-scale production of probiotics microencapsulation.

Probiotic viability is generally determined by quantifying its resistance to simulated gastric juice or to simulated intestinal fluid in in vitro tests, which measure microbial survival after given periods of contact. The use of a neutralizing agent is needed to avoid a carry-over of gastric or intestinal juice into the culture media of the subsequent analysis and to avoid any antimicrobial effect extended over the defined period of contact of the test. Neutralization of gastric juice and intestinal juice are of the utmost importance to present data accurately. Failing to do so determines a carry-over of bactericidal activity to the plates used for the enumeration, which further reduces the number of surviving cells. Examples of such incorrect adaptation of the test are available in literature. The purpose of this perspective stems from the discovery that many studies do not adhere to internationally recognized standards, e.g., EN 1040:2005 (European Committee for Standardization [ECS], 2005), to evaluate the basic, bactericidal activity of compounds, especially for the neutralization step.

There is an increasing demand for non-dairy probiotic carriers such as fruit and vegetable juices. Probiotic Lactobacillus sanfranciscensis is predominantly used in the bakery industry, and its efficacy in fruit juices has not been studied sufficiently. Additionally, support from the carrier matrices for maintaining probiotic viability and gastrointestinal tolerance is important in selecting suitable vehicles for probiotic delivery. Three different non-dairy carrier juices (apple, orange and tomato) were tested for their ability to maintain L. sanfranciscensis viable during four weeks of refrigerated storage (4 &deg, C). Their potential protection of L. sanfranciscensis against in vitro gastrointestinal digestion was also evaluated. Results indicated that the probiotics viability in all three juice samples met the recommended level for probiotic food (&gt, 106&ndash, 107 cfu/mL) at the end of storage. However, all three juice samples showed a comparatively lower protective effect (p &lt, 0.05) on the viability of L. sanfranciscensis when exposed to simulated gastric juice (pH = 2) at the end of 60 min and simulated intestinal juice with 0.3% (w/v) bile salt (pH = 8) at the end of 240 min exposure. In general, the three tested juices can be regarded as the potential non-dairy based carriers for L. sanfranciscensis. The future research is needed to improve the modification of the probiotic carriers in order to prolong the viability of L. sanfranciscensis during the gastrointestinal digestion.

This study investigated a possible relationship between exopolysaccharides (EPS) production and the resistance to bile salts and low pH in intestinal strains of Lactobacillus reuteri. The strains displayed a mucoid phenotype, when grown in the presence of 10 % sucrose. Scanning electron microscopy (SEM) revealed strands of exopolysaccharide linking neighbouring cells. The strains (except L. reuteri B1/1) produced EPS in the range from 15.80 to 650.70 mg.l−1. The strains were tested for tolerance to bile salts (0.15; 0.3 %) and low pH (1.5—2.0—2.5—3.0). The survival rate, after the treatment with artificial gastric and intestinal juices, was determined by flow cytometric analysis. The strains of L. reuteri that produced 121—650 mg.l−1 of EPS showed a significantly higher tolerance (P < 0.001) to the gastric juice at pH 3 and 2.5, throughout the entire exposure time, in comparison to the strains that produced less than 20 mg.l−1 of EPS. L. reuteri L26, with the highest production of EPS, exhibited the highest survival rate (60 %) at pH 2 after the 120 minutes of in-cubation and was able to tolerate pH 1.5 for 30 minutes. Higher production of EPS significantly (P < 0.001) increased the strains’ tolerance against the intestinal juice in the presence of 0.15 and 0.3 % bile salts and was time dependent. L. reuteri L26 showed the highest tolerance (P < 0.001) against 0.3 % bile salts. This investigation revealed a positive correlation between the EPS production and the resistance of intestinal L. reuteri to the stress conditions of the gastrointestinal tract (GIT).

The effects of goat milk fractions on the stability of insulin-like growth factor I (IGF-I) digested in the simulated gastrointestinal juice in vitro were investigated. IGF-I concentration was analyzed using an immunological sandwich-type ELISA method. The results showed that the concentration of pure IGF-I in simulated gastrointestinal juice decreased rapidly with the increasing digestion time. However, IGF-I in goat milk was more stable than pure IGF-I either in simulated gastric or intestinal juice. Goat milk and whey and whey supernatant fractions all effectively inhibited the proteolytic degradation of IGF-I in both the simulated gastric and intestinal juices. Dietary derived protease inhibitors, such as soya bean trypsin inhibitor (SBTI), lima bean trypsin inhibitor (LBTI) and egg white protease inhibitor (EWPI) all prevented IGF-I degradation in the simulated gastrointestinal juice, but the whey supernatant fraction represented more effective inhibition than the inhibitors. These results suggested that the whey supernatant fraction might contain specific inhibitors that protect IGF-I from the proteolytic degradation in the simulated gastrointestinal conditions, which was further verified by SDS-PAGE. Therefore, the whey supernatant fraction in goat milk could be a potential resource for the development of the effective oral IGF-I-based products.

For the first time, a continuous leaching method, coupled on-line with inductively coupled plasma mass spectrometry (ICPMS), was used on wheat samples to assess the maximum bio-accessibility of several trace elements. This technique involves the sequential continuous leaching of a mini-column of sample by artificial saliva, gastric juice and intestinal juice, while the effluent from the mini-column flows to the nebulizer of an ICPMS instrument. A larger mini-column than previously used with this method was utilized to improve reproducibility. The results of the continuous on-line leaching method were comparable to those of a conventional batch method despite the fact that it requires 15 min as opposed to several hours by the batch method. They show that bio-accessibility varies from element to element between samples. The bio-accessible fraction of the majority of elements (e.g. As, Fe, Ni, Cu, etc.) was mostly released by saliva and gastric juice. Particular attention was paid to Cd and Pb in wheat, because even a portion of these elements being bio-accessible could have major implications for consumers. The highest bio-accessible concentrations of Pb were found to be 780 ± 90 μg kg−1 and 890 ± 100 μg kg−1 for Safeer wheat and Qassim wheat, respectively, corresponding to 60% and 100% bio-accessibilities. Furthermore, the maximum Cd bio-accessible concentration was 1810 ± 280 μg kg−1 for Qassim wheat samples, corresponding to 100% bio-accessibility, which is a concern for consumption by children.

© 2017, Association of Food Scientists & Technologists (India). Biofortification of crops with exogenous iodine is a novel strategy to control iodine deficiency disorders (IDD). The bioaccessibility of iodine (BI) in the biofortified vegetables in the course of soaking, cooking and digestion, were examined. Under hydroponics, the concentration of iodine in leafstalks of the celery and pakchoi increased with increasing exogenous iodine concentration, 54.8–63.9% of the iodine absorbed by pakchoi was stored in the soluble cellular substance. Being soaked in water within 8 h, the iodine loss rate of the biofortified celery was 3.5–10.4% only. More than 80% of the iodine in the biofortified celery was retained after cooking under high temperature. The highest BI of the biofortified vegetables after digestion in simulated gastric and intestinal juice amounted to 74.08 and 68.28%, respectively. Factors influencing BI included pH, digestion duration, and liquid-to-solid ratio. The high BI of the biofortified vegetables provided a sound reference for the promotion of iodine biofortification as a tool to eliminate the IDD.

Currently, surgical staples are composed of non–biodegradable titanium (Ti) that can cause allergic reactions and interfere with imaging. This paper proposes a novel biodegradable magnesium (Mg) alloy staple and discusses analyses conducted to evaluate its safety and feasibility. Specifically, finite element analysis revealed that the proposed staple has a suitable stress distribution while stapling and maintaining closure. Further, an immersion test using artificial intestinal juice produced satisfactory biodegradable behavior, mechanical durability, and biocompatibility in vitro. Hydrogen resulting from rapid corrosion of Mg was observed in small quantities only in the first week of immersion, and most staples maintained their shapes until at least the fourth week. Further, the tensile force was maintained for more than a week and was reduced to approximately one-half by the fourth week. In addition, the Mg concentration of the intestinal artificial juice was at a low cytotoxic level. In porcine intestinal anastomoses, the Mg alloy staples caused neither technical failure nor such complications as anastomotic leakage, hematoma, or adhesion. No necrosis or serious inflammation reaction was histopathologically recognized. Thus, the proposed Mg alloy staple offers a promising alternative to Ti alloy staples.

Lactobacillus acidophilus NCFM (L-NCFM) was microencapsulated via co-extrusion technique with mannitol. Optimization of coating material, locust bean gum (0% to 2%, w/v) and prebiotic, mannitol (0% to 5%, w/v) was tested on bead size and microencapsulation efficiency. L-NCFM cells microencapsulated in three different forms were tested in simulated gastric juice (pH 2.0) and simulated intestinal juice (pH 7.5) and storage test at 4 °C and 25 °C for 4 weeks. 0.5% (w/v) locust bean gum and 3% (w/v) of mannitol are the optimal concentrations to produce bead size of 570 µm, microencapsulation efficiency of 96.81% and cell count 8.92 log CFU/mL. Microencapsulation of L-NCFM with mannitol protect cells better in acidic environment. The viability of encapsulated L-NCFM with mannitol at 4 °C throughout the storage period for 30 days ranged from 8.62 log cfu/mL to 6.80 log cfu/mL, which met the minimum required for probiotic (106CFU/mL).

Microencapsulation is an effective way to improve the survival of probiotics in simulated gastrointestinal (GI) conditions and yoghurt. In this study, microencapsulation of Lactobacillus rhamnosus GG (LGG) was prepared by first cross-linking of soy protein isolate (SPI) using transglutaminase (TGase), followed by embedding the bacteria in cross-linked SPI, and then freeze-drying. The survival of microencapsulated LGG was evaluated in simulated GI conditions and yoghurt. The results showed that a high microencapsulation yield of 67.4% was obtained. The diameter of the microencapsulated LGG was in the range of 52.83 to 275.16 μm. Water activity did not differ between free and microencapsulated LGG after freeze-drying. The survival of microencapsulated LGG under simulated gastric juice (pH 2.5 and 3.6), intestinal juice (0.3% and 2% bile salt) and storage at 4 °C were significantly higher than that of free cells. The survival of LGG in TGase cross-linked SPI microcapsules was also improved to 14.5 ± 0.5% during storage in yoghurt. The microencapsulation of probiotics by TGase-treated SPI can be a suitable alternative to polysaccharide gelation technologies.

The aim of this study was to prepare the rosiglitazone sodium enteric-coated tablets and investigate its release rate. The rosiglitazone sodium enteric-coated tablet was prepared by single punch tablet press using substituted hydroxypropyl cellulose and polyvinylpyrrolidone (PVP). The release rate from the enteric-coated tablet of rosiglitazone sodium was evaluated. The release rate study showed that few rosiglitazone sodium was released from enteric coated formulation within 2 h in simulated gastric juice, while it released more than 80% of the labeled amount in 30 min in simulated intestinal juice. The preparing method of rosiglitazone sodium enteric-coated tablets was simple and had a good reproducibility. The release condition and determined methods could be used for the routine determinations of rosiglitazone sodium enteric-coated tablets.

Zuota is regarded as the king of Tibetan medicine. However, the major starting material of Zuota is mercury, which is one very toxic heavy metal. This has aroused serious doubts on the biosafety of Zuota containing drugs. In this study, we quantified the Hg contents in four Zuota samples, monitored the release of Hg in simulated gastric/intestinal juice and evaluated their cytotoxicity to Caco-2 cells. Our results showed that the Hg contents in Zuota samples were in the range of 566-676 mg/g. Fortunately, the release of Hg from Zuota samples was very low in simulated gastric juice, and much lower in simulated intestinal juice. Direct contact of Zuota with Caco-2 cells led to dose-dependent cytotoxicity, including activity loss and membrane leakage. The toxicity was closely related to apoptosis, because the caspase 3/7 levels of Caco-2 cells increased after the exposure to Zuota. Interestingly, Zuota samples inhibited the oxidative stress at low concentrations, but the toxicity could be relived by antioxidants. The possible toxicity should be attributed to the cellular uptake of Zuota particulates. Beyond the cytotoxicity, significant differences among Zuota samples from different institutions were observed, suggesting that the preparation process of Zuota had meaningful influence of its biosafety. The implications to the safety and clinical applications of Zuota are discussed.

The aim of this study was to evaluate the bioaccessibility of Ca, Fe, Mg, Mn, and Zn in cat’s claw plant teas through in vitro gastrointestinal digestion with gastric and intestinal juice solutions. The total concentrations and bioaccessible fractions of Ca, Fe, Mg, Mn, and Zn were measured by flame atomic absorption spectrometry (FAAS). The results obtained showed that Zn was the most bioaccessible element in the teas, contributing a mean of 57.9% by infusion and 62.5% by decoction. Among macroelements, the Ca was less bioaccessible with 17.4% recovery. The bioavailability assessment revealed that daily intake of 200 ml of cat’s claw teas cover about 1.0% of manganese RDA.

This study was supported by Drug Applied Research Center, Tabriz University of Medical Sciences. All experiences were done in Microbiology laboratory of Drug Applied Research Center. We thank general laboratory staff and Mr. Vatankhah for his collaboration., Aims: In order to improve survival in gastrointestinal conditions, probiotic bacteria, i.e. we developed a new encapsulation method of probiotics based on zeolite and by calcium-alginate zeolite-starch as an effective method for safer delivery of probiotics. Material and Methods: Lactobacillus casei (ATCC 39392) and Lactobacillus plantarum (ATCC 29521) were used as probiotics. After microorganism’s immobilization on zeolite base, encapsulation was done by calcium-alginate zeolite-starch with the extrusion method. Afterwards, they were incubated in the simulated gastric and intestinal condition. Viability of these bacteria was calculated on the basis of time required to reduce the logarithmic base in the microbial population. SEM techniques were used to study the appearance of the capsules. Results: after incubation for 120 min under simulated gastric condition and 180 min in intestinal juice conditions (pH=8.2), the count of alive L. casei and L. plantarum cells were 6.3 log cfu/ml and 7.3 log cfu/ ml. However, for controlling the cells, this value was zero and 2.1 log cfu/ml respectively. Conclusion: According to the results, we had an increase of the survival rate of L. casei and L. plantarum in gastroesophageal-intestine simulated condition. These results indicated good efficacy and high performance of zeolite for immobilization and microencapsulation of probiotics., Objetivos: Para mejorar la supervivencia en condiciones gastrointestinales de las bacterias probióticas, hemos desarrollado un nuevo método de encapsulación de probióticos a base de zeolita y almidón de zeolita de alginato de calcio como método eficaz para la administración más segura de probióticos. Material y métodos: se utilizaron Lactobacillus casei (ATCC 39392) y Lactobacillus plantarum (ATCC 29521) como probióticos. Después de la inmovilización del microorganismo en la base de zeolita, la encapsulación se realizó mediante zeolita-almidón de alginato de calcio con el método de extrusión. Posteriormente, se incubaron en la condición gástrica e intestinal simulada. La viabilidad de estas bacterias se calculó sobre la base del tiempo requerido para reducir la base logarítmica en la población microbiana. Las técnicas SEM se usaron para estudiar la apariencia de las cápsulas. Resultados: después de la incubación durante 120 minutos bajo condición gástrica simulada y 180 minutos en condiciones de jugo intestinal (pH = 8,2), el recuento de células vivas de L. casei y L. plantarum fue de 6,3 log ufc / ml y de 7,3 log ufc / ml. Sin embargo, para controlar las células, este valor era cero y 2,1 log cfu / ml respectivamente. Conclusión: De acuerdo con los resultados, tuvimos un aumento de la tasa de supervivencia de L. casei y L. plantarum en condiciones simuladas de gastroesofágico-intestino. Estos resultados indicaron buena eficacia y alto rendimiento de zeolita para inmovilización y microencapsulación de probióticos.

To accelerate the response rate of smart hydrogels to the environmental conditions, a novel pH-sensitive p(PEGMA-g-MAA) hydrogel microsphere with the controlled shapes and sizes were developed. Such monodispersed microspheres were synthesized via free radical polymerization under the protection of a multilayer stability system. The pH-responsibility of hydrogel microspheres was tested with the hydrogel bulk as a control. In vitro release studies were conducted in the simulated gastric fluid and intestinal juice with bovine serum albumin (BSA) as a model drug. The large specific surface areas endowed hydrogel microspheres a faster pH-responsibility than that of hydrogel bulk. In vitro release profiles showed that over 90 % BSA were released from hydrogel microspheres under the alkaline conditions (pH 7.4), which was faster than those from hydrogel bulks. In sum, the rapid pH-responsibility and ideal drug release profile could shorten the lag time to steady plasma-drug concentration, which was beneficial to increasing the therapeutic effect of the drugs.

Summary Background & aims Some problems such as gastroesophageal reflux, vomiting and diarrhea are cited complications associated with enteral nutrition. Half-solidified formulas can reduce these problems; however, such formulas cannot be administered through nasogastric tubes, and are, therefore, not as convenient as liquid formulas. To solve these problems, we have developed a new type formula which includes the alginate. It has the functions of both liquid and half-solidified type. In this study, we performed functional evaluations of this new type formula. Methods The state changes of three type formulas in artificial gastric/intestinal juice were compared by evaluating the “solidification rate”. Moreover, in rat stomach, state changes of each formula were evaluated by studying the “intragastric holding rate” and the “intragastric solidification rate”. Results The new type formula could be administered through nasogastric tubes. It changed into a semi-solidified state in artificial gastric juice and liquefied in artificial intestinal juice. In rats, the intragastric solidification rate of the new type formula was 79 ± 3%, and the intragastric holding rate was 80 ± 6%. These results were similar to those observed for the half-solidified formula. Conclusion The new type formula (A) can be administered through nasogastric tubes, (B) changes into the “semi-solidified state” from the liquid state in rat stomach, and (C) changes back to the “liquid state” in intestinal juice. The new type formula changed its state depending on pH. These results suggest that the new type formula has the advantages of both liquid and half-solidified formulas.

Radix Isatidis is a traditional Chinese medicine for treatment of influenza and inflammation in China. In this paper, in order to study the degradation situation of Radix Isatidis polypeptide in artificial gastrointestinal environment, the SDS-PAGE (Sodium dodecyl sulfate-polyacrylamide gel electrophoresis) method was used to detect the degradation of Radix Isatidis polypeptide in artificial intestinal juice and gastric juice, and it showed that Radix Isatidis peptides could be degradated to different degrees. HPLC (High Performance Liquid Chromatography) was used to determine the change of peptides degradation, and it indicated that free amino acid levels did not change significantly. The result after degradation was also detected by BCA method, and it showed that there were still a large number of polypeptides in the liquid. From this experiment we can come to this conclusion that Radix Isatidis polypeptides in artificial gastrointestinal juice mostly degraded into a series of different molecular weight peptides.

To accelerate the response rate of smart hydrogels to the environmental conditions, a novel pH-sensitive hydrogel microsphere with the controlled shapes and sizes were developed. Such monodispersed microspheres were synthesizedviafree radical polymerization under the protection of a multilayer stability system. The pH-responsibility of hydrogel microspheres was tested with the hydrogel bulk as a control.In vitrorelease studies were conducted in the simulated gastric fluid and intestinal juice with bovine serum albumin (BSA) as a model drug. The large specific surface areas endowed hydrogel microspheres a faster pH-responsibility than that of bulk ones. Therefore, such microspheres showed potential applications as the oral protein drugs carrier.

Phycobiliprotein is a kind of bioactive material that is widely used in the fields of food and medicine. However, the usage of phycobiliprotein is limited by its instability. In this study, we firstly developed a kind of phycobiliprotein microcapsulate by chitosan-sodiumalginate encapsulation method. The preparation conditions, stability and controlled release of phycobiliprotein microcapsule were studied and discussed. The results showed that the optimal conditions for preparing the microcapsulates were 3% sodium alginate, 3% CaCl 2 and 0.5% chitosan. After encapsulation, the stabilities of phycobiliprotein to heat, acidity and radiation were greatly improved. Phycobiliprotein in microcapsulate was 5-10 times more endurable than in water solution when heated and 7 times when radiated. Stability under acidity was also improved greatly. It was also found that phycobiliprotein microcapsulate had good stability in the mimic gastric juice and had 90% release rate in the mimic intestinal juice. This suggests that phycobiliprotein microcapsulate can have controlled release and dissolution in intestine.

A core-shell gelatin-alginate composite used for intestine-released oral delivery drug carrier was synthesized through microfluidic technique. At the fixed continuous phase flow rate, the size of the core-shell gelatin-alginate microparticles increases with the dispersed phase flow rate, and monodispersity can be retained (the variation coefficient for the diameter distribution can be kept less than 10%). The fabricated microparticles could remain intact in gastric juice for at least 3 h, indicating that the gelatin core could be well protected by alginate shell in acid environment. However, the alginate shell of the microparticles would swell or collapse in alkali environment in half an hour, assuring the controlled drug release in intestinal juice. The fabricated uniform core-shell gelatin-alginate microparticles were potential as pH-responsive drug carriers.

The survival of Lactobacillus delbrueckii UFV H2b20 was assessed in fermented milk, both during the storage period and after exposure to simulated gastric and intestinal juices, as well the detection of the gene fbpA involved in adherence to human gastrointestinal tract. L. delbrueckii UFV H2b20 remained stable and viable for 28 days under refrigerated storage conditions. After one day of storage, that strain exhibited a one-log population reduction following exposure in tandem to simulated gastric and intestinal juices. After 14 days of storage, a two-log reduction was observed following 90 min of exposure to the simulated gastric conditions. However, the strain did not survive following exposure to the simulated intestinal juice. The observed tolerance to storage conditions and resistance to the simulated gastric and intestinal conditions confirm the potential use of L. delbrueckii UFV H2b20 as a probiotic, which is further reinforced by the detection of fbpA in this strain.

There are no ideal means for the diagnosis of intestinal bleeding diseases as of now, particularly in the small intestine. This study investigated an intelligent intestinal bleeding detection capsule system based on color recognition. After the capsule is swallowed, the bleeding detection module (containing a color-sensitive adsorptive film that changes color when absorbing intestinal juice,) is used to identify intestinal bleeding features. A hue-saturation-light color space method can be applied to detect bleeding according to the range of H and S values of the film color. Once bleeding features are recognized, a wireless transmission module is activated immediately to send an alarm signal to the outside; an in vitro module receives the signal and sends an alarm. The average power consumption of the entire capsule system is estimated to be about 2.1mW. Owing to its simplicity, reliability, and effectiveness, this system represents a new approach to the clinical diagnosis of intestinal bleeding diseases.

Zinc is one of those microelements that are essential for the proper functioning of the human body and must be supplemented in our food at a daily dose of 15 mg. It is well known that mushrooms accumulate elements; thus, in order to determine the extent of accumulation and the level of zinc released from mushrooms, in vitro cultures of Agaricus bisporus were established. The cultures were run on a modified Oddoux medium (a control culture) as well as on the same medium with the addition of zinc hydroaspartate (100 and 200 mg/L) and zinc sulfate (87.23 and 174.47 mg/L). These compounds were chosen to help estimate which form, organic or inorganic, results in a better assimilation of zinc(II) ions by biomass. As the next step, the level of zinc(II) ions released from the lyophilized biomass of in vitro cultures to the digestive juices, under thermal conditions of the human body (37°C), was determined. For this purpose, artificial digestive juices, imitating the composition of human digestive juices, were used. For determination of zinc(II) ions in the digestive tract, an anodic stripping voltammetry method was employed. The amount of zinc released into artificial saliva over 1 minute varied from 0.15 mg/100 g d.w. in the control culture to 2.35 mg/100 g d.w. in the biomass in the medium to which 200 mg/L zinc hydroaspartate had been added. Values were higher in gastric juice and depended on incubation time (2.66 to 30.63 mg/100 g d.w.). In intestinal juice, the highest value of the released zinc grew to 24.20 mg/100 g d.w. (biomass of A. bisporus in vitro cultures in medium with the addition of 200 mg/L zinc hydroaspartate). Total average amount of zinc released into artificial digestive juices was the highest (56.26 mg/100 g d.w.) from A. bisporus biomass of in vitro cultures in the medium to which 200 mg/L zinc hydroaspartate had been added.

A continuous leaching method, coupled online with inductively coupled plasma mass spectrometry (ICP-MS) was used on seafood samples to assess the maximum bioaccessibility of several trace elements. The method indeed involves continuous leaching of the food sample by artificial saliva and gastric juice, successively, where this exposition of the food to fresh reagent drives the dissolution equilibrium to the right. Leaching with intestinal juice had to be omitted because it resulted in clogging problems. The experimental apparatus includes a mini-column of powdered sample, which is directly connected to the nebulizer of an ICP-MS instrument. The on-line approach allows a quick assessment of the maximum bioaccessibility of elements of interest by monitoring the real-time release of elements by a given reagent. The method was applied to determine the bioaccessibility of four toxic elements (Al, Cd, Hg, and Pb) and of four essential elements (V, Mn, Cu, and Zn) in certified reference materials and in actual seafood samples. In all cases, mass balance was verified by carrying out the total digestion of the remaining residue from the mini-column and the relationship between total concentration and bioaccessibility was examined.

This study investigated pure Lactobacillus paracasei H9 tolerance to simulated gastrointestinal juices and adhesion to intestinal mucosa cells without yeasts, with viable yeasts (VY) and with different pretreated yeasts. Three models including gastric secretion tolerance (GST), intestinal juice tolerance (IJT) and sequential gastrointestinal tolerance (SGT) were respectively employed to assay the tolerance of L . paracasei H9, whilst Caco-2 cell line was used to investigate the bacterial adhesion. Particularly, the co-aggregation ability of the two strains at pH values of 2.0, 8.0 and 7.2 was originally carried out to study relations to the bacterial probiotic potentials. Results showed that yeast counts in the range from 3.0 to 5.0 log CFU mL − 1 could gradually increase the viability of L . paracasei H9 in SGT. The bacterial viability in the three tolerance models and the adherent number to Caco-2 cells were significantly improved with addition of VY ( P L . paracasei H9 with VY in gastric juice at pH 2.0 and intestinal juice at pH 8.0, respectively, exhibited higher aggregation percentage compared with that of single L . paracasei H9 at 37 °C ( P L . paracasei H9 with VY at pH 7.2, which might contribute to increase the adhesion of the bacteria, also excelled that of L . paracasei H9 ( P L . paracasei H9.

This study was conducted to determine the oxalate contents in common nuts either locally grown or imported into New Zealand. Samples of imported nuts were purchased from supermarkets in Christchurch while locally grown nuts were obtained directly from the growers. In this experiment gastric soluble and intestinal soluble oxalates were extracted from the nuts using an in vitro assay, which involved incubations of the food samples for 2 h at 37 °C in gastric and intestinal juice. The extracted oxalates were then determined by HPLC chromatography. Roasted pistachio nuts and chestnuts contained very low levels (

Received 13 March 2006; accepted 17 October 2006DOI 10.1002/app.25666Published online 25 July 2007 in Wiley InterScience (www.interscience.wiley.com).ABSTRACT: Ultrafine fiber mats of hydroxypropylmethyl cellulose phthalate (HPMCP) were successfullyelectrospun and explored as drug delivery vehicles usingerythromycin as a model drug. The morphology of theelectrospun fiber and the drug release process in the arti-ficial gastric juice and in the artificial intestinal juice wereinvestigated. With the same drug-to-matrix ratio(HPMCP/erythromycin ¼ 9/1), all the fibers were electro-spun into a tape-like or ribbon shape and the averagefiber diameter (AFD) was increased with the HPMCPconcentration. Because of the pH-sensitive property ofHPMCP, erythromycin was released from the erythromy-cin-containing electrospun HPMCP fiber mats by a slowlydiffusion process in the artificial gastric juice, while itwas released in nearly first-order kinetics in the artificialintestinal juice because of the first-order kinetics dissolu-tion of the HPMCP fibers in the artificial intestinal juice.And the rate of erythromycin released in the artificial in-testinal juice was about more than 2.5 times faster thanthat in the artificial gastric juice. The diameter of thefibers plays an important role on the rate and the totalamount of the drug released both in stomach and inintestine, the rate and the total amount of the drugreleased decreasing with increasing AFD.