Hydrogel Encapsulation of Lactobacillus casei by Block Charge Modified Pectin and Improved Gastric and Storage Stability

Lactobacillus casei (L. casei W8) was encapsulated in pectin methylesterase (PME) charge modified pectin hydrogels; stability and in vitro release were evaluated under simulated gastrointestinal (GI) conditions. PME, 355 U/mL, de-esterified citrus pectin to 35% from 72% degree of esterification (DE). Pectin ζ-potential decreased to about −37 mV and molecular weight decreased from 177 kDa to 143 kDa during charge modification. More than 99% L. casei W8 were encapsulated in block charged, low methoxy pectin (35 mLMP) hydrogels by calcium ionotropic gelation. The integrity of the hydrogels was maintained under simulated GI conditions, and no release of L. casei W8 was observed. Microbial counts of encapsulated L. casei ranged from 6.94 log CFU/g to 10.89 log CFU/g and were 1.23 log CFU/g higher than for unencapsulated L. casei W8. The viability of encapsulated L. casei W8 in wet hydrogels remained the same for 2 weeks, but nearly all flora died after 4 weeks storage at 4 °C. However, freeze dried hydrogels of L. casei W8 were viable for 42 days at 4 °C and 14 days at room temperature. Charge modified pectin hydrogels are potentially good vehicles for colon-targeted delivery carrier for probiotics and longer stability of L. casei W8

Effects of biopolymer ratio and pH value on the complex formation between whey protein isolates and soluble Auricularia auricular polysaccharides

Biopolymer complexes fabricated by proteins and neutral polysaccharides have some specific and innovative functionalities. A better understanding of the interactions among these biopolymers might provide new insight into the applications of the complexes. Therefore, this study aimed to investigate the structural characteristics and molecular interaction mechanisms of whey protein isolates (WPI) and Auricularia auricular polysaccharides (APs). The turbidity analysis confirmed that the pH value and mixing ratio of the two polymers had strong effects on the formation of the APs-WPI complexes. All dispersions formed soluble complexes at approximately pH = 6.0 (pHc). APs-WPI self-assembles exhibited physically cross-linked networks under higher APs proportions, while they formed spherical complexes at higher WPI ratios. The addition of APs could alter the secondary structure of WPI, and the most noticeable changes were located in the regions of β-sheet and β-turn as confirmed by circular dichroism (CD) analysis. A molecular docking study showed that the amino acid residues of β-lactoglobulin complexed with the –COOH and –OH groups of APs. Hydrogen bonds and hydrophobic interactions, which were nonbonding contributions, played a key role in the formation of the APs-WPI complex. This study provided a basis for the development and application of APs in WPI-based beverages

Effects of Growth Period and Germination Treatment on Saponin Content of Different Bean Varieties

In order to improve the processing and utilization value of the Northeast snap beans products by clarifying the saponin content, sites and influencing factors, this study extracted saponins from the seeds and pods of seven kinds of Northeast snap beans, including Golden Crown, Green Crown, and Sheng Crown within 10~40 d after blooming using ultrasonic-assisted methods. 0.4%~1.2% sodium chloride solution was used to conduct germination treatment under salt stress on the saponin content of Golden Crown and Mantangcai seed. Finally, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) was used to identify the saponin species in the seeds of Golden Crown. The results showed that saponin existed mainly in the seeds, and the saponin content increased firstly but then decreased with the increase of growth time. The peak period of saponin content varied with the bean varieties. Compared with the other six varieties of snap beans, the saponin content in the full hall was the highest, with the highest saponin content of Mantangcai whole pods of 23.62±0.14 mg/g at 35 d. The change of saponin content was closely related to the sprouting time of bean seeds and bean varieties. Salt stress treatment could significantly increase the saponin content of Mantangcai seeds from (7.08±0.15) mg/g to (10.15±0.55) mg/g. The UHPLC-Q-TOF-MS analysis showed that there were seven saponins in the crude saponins of the Golden Crown bean, including saikosaponin F, adzuki saponin II and astragaloside IV. This study provides data support for the in-depth development of soybean saponins in Northeast China

Quality Analysis of Different Varieties of Potato Snowflakes Powder

In this study, 11 varieties of potatoes were selected as raw materials to process whole powder under the same conditions. The quality differences of snowflake whole powder prepared by different varieties of potatoes were studied by measuring components, iodine blue value, chroma, water holding capacity (WHC), oil holding capacity (OHC), freeze-thaw stability and other indicators, so as to clarify the influence of different varieties of potatoes on the quality of whole powder. The results showed that the Longshu 6 had the strongest WHC (9.84 g/g), OHC (1.63 g/g) and coagulation capacity, and the attenuation value (315.2 RVU) was significantlyhigher than that of the other varieties (P<0.05). Longshu 15 had the highest water content (9.20%). Longshu 9 had the highest viscosity (589.4 RVU) and the strongest shear resistance, but the retrogradation value was 33.9 RVU, with strong gelation and easy aging. Longshu 18 had the highest protein content of 12.29 g/100 g, but less starch content (46.24 g/100 g), the highest water absorption rate (0.55%) and the worst freezing resistance, so it is not suitable for processing products that need to be frozen and stored. The reducing sugar content of Atlantic (0.24 g/100 g) was significantly lower than that of other varieties (P<0.05), the iodine blue value (26.28) was the highest, and the free starch content was the highest. Longshu 15 had the largest L* value (91.49) and smaller b* value (14.96), with bright colors and a more marketable appearance. This study would provide data support for the selection of dominant potato varieties for the development of potato whole powder by comparing the relationship between potato quality and varieties

Long-term inducible expression in striatal neurons from helper virus-free HSV-1 vectors that contain the tetracycline-inducible promoter system

Photograph used for a story in the Daily Oklahoman newspaper. Caption: "Expensive rubble piles up on sidewalk in front of Rosenfield's Jewelers, 227 W Main, after a blaze ripped through the building Sunday morning. A fireman is shown digging into the rubble trying to salvage some of the heavy silver that was on display near the front of the store. Jewelry, shina, silver and TV and hi-fi sets were destroyed in the blaze. Lane's Quality Shoes, 223 W Main, and Stevens, 229 W Main, were damaged by some smoke and water. The jewelry store was destroyed, but the loss has not been estimated.

Antibacterial mechanisms, whole genome sequencing and potential functional prediction of Lactoplantibacillus plantarum L3

In our previous study, we have isolated Lactoplantibacillus plantarum L3 (GenBank accession No. MT781360) which can secret bacteriocin L3 with broad-spectrum antibacterial activities. This work aimed to illustrate the antibacterial mechanism of bacteriocin L3 and predict the functionalities of the L. plantarum L3 strain through whole genome analysis. Preliminary exploration of the bacteriostatic mechanism showed that bacteriocin L3 destroyed the cell membrane integrity and led to the extravasation of the cell contents, leading to cell death. The sequencing results showed that the genome of Lactobacillus plantarum L3 was 3 187 020 bp in size, with a GC content of 44.57%. Overall, 3 024 encoding genes were annotated, with a sequence length of 2 679 162 bp, accounting for 84.06% of the total genome length. The strain has strong reproductive and metabolic abilities and high safety. The bacteriocin gene cluster analysis showed that the bacteriocins L3 belonged to the class IIb bacteriocins. This work might provide a theoretical basis for the application of this strain in the food industry, especially its potential use in dairy products

Beneficial Effects of Non-Encapsulated or Encapsulated Probiotic Supplementation on Microbiota Composition, Intestinal Barrier Functions, Inflammatory Profiles, and Glucose Tolerance in High Fat Fed Rats

Development of obesity-associated comorbidities is related to chronic inflammation, which has been linked to gut microbiota dysbiosis. Thus, modulating gut microbiota composition could have positive effects for metabolic disorders, supporting the use of probiotics as potential therapeutics in vivo, which may be enhanced by a microencapsulation technique. Here we investigated the effects of non-encapsulated or pectin-encapsulated probiotic supplementation (Lactobacillus paracasei subsp. paracasei L. casei W8&reg;; L. casei W8) on gut microbiota composition and metabolic profile in high-fat (HF) diet-fed rats. Four male Wistar rat groups (n = 8/group) were fed 10% low-fat, 45% HF, or HF with non-encapsulated or encapsulated L. casei W8 (4 &times; 107 CFU/g diet) diet for seven weeks. Microbiota composition, intestinal integrity, inflammatory profiles, and glucose tolerance were assessed. Non-encapsulated and pectin-encapsulated probiotic supplementation positively modulated gut microbiota composition in HF-fed male rats. These changes were associated with improvements in gut barrier functions and local and systemic inflammation by non-encapsulated probiotics and improvement in glucose tolerance by encapsulated probiotic treatment. Thus, these findings suggest the potential of using oral non-encapsulated or encapsulated probiotic supplementation to ameliorate obesity-associated metabolic abnormalities