Probiotics are viable nonpathogenic microbes that positively affect host health. Probiotics inhibit infection, activate immunity, and promote mucosal-barrier development. Many microbes have probiotic activity. Nonetheless, the selection of stable strains and their specific mechanism(s) of action are not fully elucidated. Bacteria from ‘Amabere amaruranu’ cultured milk from Kenya were isolated and identified by PCR sequence analysis of the 16S rRNA gene. Isolates were examined for stability to acid and bile, antimicrobial activity, mucin production, and degradation and sensitivity to antibiotics, hence their potential for probiotics. Lactobacillus isolates were acid unstable, bile-stable, nonmucinolytic, and presented antibacterial activity. L. rhamnosus cell fractions increased MUC4 and MUC3 expression in colon cells. Bacillus isolates were acid and bile stable, nonmucinolytic and lacked antimicrobial activity. In conclusion, Lactobacillus isolates that were nonmucinolytic, stable in bile, demonstrated antibacterial activity, sensitive to antibiotics, and stimulated increase MUC4 and MUC3 levels in colon cells could be potential probiotics.

Aerobic and anaerobic performance of the upper body (UB) and lower body (LB) were assessed by arm cranking and treadmill tests respectively in a comparison of national (N) and international (I) male gymnasts. Force velocity and Wingate tests were performed using cycle ergometers for both arms and legs. In spite of a significant difference in training volume (4–12 vs. 27–34 h·wk−1 for N and I, respectively), there was no significant difference between N and I in aerobic and anaerobic performance. Upper body and LB maximal oxygen uptake (JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max) values were 34.44 ± 4.62 and 48.64 ± 4.63 ml·kg−1·min−1 vs. 33.39 ± 4.77 and 49.49 ± 5.47 ml·kg−1·min−1, respectively, for N and I. Both N and I had a high lactic threshold (LT), at 76 and 82% of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max, respectively. Values for UB and LB force velocity (9.75 ± 1.12 and 15.07 ± 4.25 vs. 10.63 ± 0.95 and 15.87 ± 1.25 W·kg−1) and Wingate power output (10.43 ± 0.74 and 10.98 ± 3.06 vs. 9.58 ± 0.60 and 13.46 ± 1.34 W·kg−1) were also consistent for N and I. These findings confirm the consistency of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max values presented for gymnasts in the last 4 decades, together with an increase in peak power values. Consistent values for aerobic and anaerobic performance suggest that the significant difference in training volume is related to other aspects of perfomance that distinguish N from I gymnasts. Modern gymnastics training at N and I levels is characterized by a focus on relative strength and peak power. In the present study, the high LT is a reflection of the importance of strength training, which is consistent with research for sports such as wrestling. Aerobic and anaerobic performance of the upper body (UB) and lower body (LB) were assessed by arm cranking and treadmill tests respectively in a comparison of national (N) and international (I) male gymnasts. Force velocity and Wingate tests were performed using cycle ergometers for both arms and legs. In spite of a significant difference in training volume (4–12 vs. 27–34 h·wk−1 for N and I, respectively), there was no significant difference between N and I in aerobic and anaerobic performance. Upper body and LB maximal oxygen uptake (JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max) values were 34.44 ± 4.62 and 48.64 ± 4.63 ml·kg−1·min−1 vs. 33.39 ± 4.77 and 49.49 ± 5.47 ml·kg−1·min−1, respectively, for N and I. Both N and I had a high lactic threshold (LT), at 76 and 82% of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max, respectively. Values for UB and LB force velocity (9.75 ± 1.12 and 15.07 ± 4.25 vs. 10.63 ± 0.95 and 15.87 ± 1.25 W·kg−1) and Wingate power output (10.43 ± 0.74 and 10.98 ± 3.06 vs. 9.58 ± 0.60 and 13.46 ± 1.34 W·kg−1) were also consistent for N and I. These findings confirm the consistency of JOURNAL/jscr/04.02/00124278-200611000-00029/ENTITY_OV0312/v/2017-07-20T235327Z/r/image-pngO2max values presented for gymnasts in the last 4 decades, together with an increase in peak power values. Consistent values for aerobic and anaerobic performance suggest that the significant difference in training volume is related to other aspects of perfomance that distinguish N from I gymnasts. Modern gymnastics training at N and I levels is characterized by a focus on relative strength and peak power. In the present study, the high LT is a reflection of the importance of strength training, which is consistent with research for sports such as wrestling.

A challenge study to validate a 5 log10 CFU/g reduction of non-O157 Shiga-toxin producing Escherichia coli (STEC) in dry fermented sausage (DFS) was performed. A 4.49 ± 0.474 log10 CFU/g was achieved over two trials. The results indicated that the process was not effective in reducing the pathogen to the level required of most pathogens by the USDA. Lactobacillus salivarius L28 (L28) was screened in vitro for the ability to inhibit STEC utilizing the paper disk diffusion method. This strain is a known bacteriocin producer. The results revealed that L28 would be a good candidate for use as a protective culture as large zones of inhibition were noted against the STEC. No zones of inhibition were noted against the commercial starter culture; therefore, it would not adversely impact the quality of the DFS. The supplementary L28 strain was added to a commercial starter culture to provide an additional hurdle in the protection against STEC. The sausage trial showed the additional strain did not offer a significant difference in reduction of the pathogen (p > 0.05). Further study will be required before L28 could be considered for use as a bioprotective culture.

Probiotics are marketed throughout the world to promote the health of the consumer by improving the microorganisms that normally occur in the intestinal tract (Tannock, 1997). It has also been suggested that probiotics can prevent pathogen infections by adhering to the intestinal mucosa (Lee, Lim, Teng, Ouwehand, Tuomola, & Salminen, 2000). While probiotics can be delivered to the infected areas in multiple fashions, microencapsulation is a newer form of delivering probiotics straight to the infected area. A whey protein microcapsule is thought to protect the probiotics from stomach acid and delivers the treatment to the affected area. To ensure this microencapsulation treatment is affective, the microcapsules will be stained and imaged to see if the microcapsules are constructed in a way which is consistent with the theory: a whey protein microcapsule surrounding bacteria and fat droplets. Through these experiments, it was shown that the microcapsule was not constructed as previously thought. Instead of a thin layer of protein surrounding the bacteria, it more closely resembled a solid ball of protein with bacteria and fat trapped inside. The bacteria are able to survive stomach like conditions (0.1M HCl for 8 hours) due to other forms of microencapsulation.

The metabolic pathways required for adenosine triphosphate (ATP) production within the cell are well understood, however recent publications suggest that metabolic pathways are closely linked to immune cell activation and inflammatory diseases. There has been little examination of the metabolic pathways that modulate mast cell activation and the feedback regulator lactic acid. Here we examine metabolic pathways and regulation within mast cells in the context of lipopolysaccharide (LPS) and interleukin (IL-33) activation, for which there has been little to no reported studies. First, we examine the effects of lactic acid, previously considered only a by-product of glycolysis and now understood to act as a negative feedback regulator of inflammation in the context of LPS activation and sepsis. Lactic acid is elevated in septic patients and associated with mortality, potentially due to suppressive effects on LPS signaling and contribution to late phase immunosuppression. By attenuating glycolysis and reducing ATP availability for signaling and cytokine transcription, lactic acid impairs the function of immune cells to fight the initial or subsequent infections. We support this with in vitro and in vivo data. Additionally, our lab has published that lactic acid can suppress IL-33 activation, potentially by metabolic modulation as with LPS activation; however there has been no study of the metabolic requirements for IL-33 activation. We report here that glycolysis is required for ATP and reactive oxygen species (ROS) production to augment signaling and cytokine production downstream of the IL-33 receptor. Together, these studies examine the contribution of metabolism to mast cell activation and may provide potential targets for treatments of diseases that involve LPS- or IL-33-dependent mast cell activation.

In the field of maxillofacial surgery, the treatment for the recovery of the fracture at condyle region of the mandible has been carried out using Bio-metals such as Titanium, Cobalt, Stainless-Steel because they were considered the standard materials for Implant plate devices for fracture fixation. Using these materials have led to undesired disturbances where the patient must undergo secondary surgery after recovery leading to exposure of the fracture site to the surrounding, metal-ion release into the human system, stress-shielding and interruption during imaging i.e. (Computerized tomography scans). The healing of the mandible requires a delicate and stable fixation procedure for the bone structure to heal. Bio-resorbable materials are the renovation for substituting metals for recovery of the fracture. The main dis-advantage using resorbable plates is absence of mechanical strength and stability. Bio-composites are the innovation for the treatment of the fractures the main study for this thesis is comparing the combination bio-ceramic and bio-resorbable materials using Finite Element Analysis software.

The effects of whey-based and milk -based starter media, and low concentrations (0.02% each) of citrate, phosphate and calcium upon various milk coagulation properties were measured. Samples inoculated with milk-based starter medium had shorter coagulation times, faster rate of curd formation, and greater final curd firmness than those inoculated with externally neutralized whey-based starter. Starter medium treatment was statistically interacted with calcium for coagulation time and rate of curd formation. Citrate addition caused longer coagulation times, slower rates of curd formation, and weaker final coagula. Citrate interacted with calcium and phosphate for several of the parameters measured. Addition of phosphate did not affect any of the measured parameters but was involved in several significant two-factor interactions as was calcium addition.

A new innovative product, stewsticks, made with beef, pork, spices, and dehydrated vegetables, was developed as a nutritious snack. Lactic or citric acid was added at pH 5.2 or 4.6 to both meatsticks and stewsticks. Meatsticks and stewsticks were prepared by mixing ingredients until a cohesive mass was obtained. This mixture was then extruded into sticks that were cooked to about 50% of original weight. Sticks were then cut to desired length, packaged, and stored. Then meatsticks (beef, pork, and spices) were compared to stewsticks for appearance, texture, flavor, and overall acceptability. The stewsticks had excellent shelf life due to combined hurdles of pH 5.2, water activity of 0.95 or less, salt, and vacuum packaging. Compared to meatsticks, one serving (2 ounces) of stewsticks had less fat (9 vs 11 g respectively), less cholesterol (75 vs 90 mg) and more dietary fiber (4 vs 2 g), carbohydrates (20 vs 4 g), vitamin A (11 vs 2% RDA), and vitamin c {32 vs 1% RDA). The type of acid did not affect panel preference, but the samples at pH 5.2 were preferred over samples at pH 4.6. overall, meatsticks were preferred by the consumer panel over stewsticks although there were 25% of them who rated stewsticks as moderately acceptable or higher.

A Spiral Plater and a Microtiter system were used to isolate and evaluate cultures for a paired strain culture program. Bacteriophage and temperature sensitivity data of 43 Streptococcus cremoris strains were introduced into a computer cluster program to pair the least similar strains. Selected pairs were challenged with phage. Resistant mutants were developed. Characteristics of proteinase positive and proteinase negative variants were examined. Proteinase positive isolates produced more changes in pH, cell mass and more generations in milk than their counter-parts. Paired proteinase negative cultures produced more change in pH and cell mass and more generations in milk than single strains. Whey based medium under pH control was superior to commercial internal pH control medium for proteinase negative culture propagation. Proteinase negative isolates achieved 90% of the cell mass obtained by their counterparts in nonfat dry milk-yeast medium. Proteinase negative starter culture endured significantly higher phage titers than proteinase positive cells. Proteinase negative variants sustained activity comparable with phage-free controls when challenged for seven cycles with high phage titers. Proteinase positive cells had impaired activity after the second cycle. Pairing of proteinase positive strains was advantageous for phage protection. Erythromycin, streptomycin and penicillin adversely affected the activity of both cell types, yet proteinase positive cells were significantly more inhibited. Pairing neither variant enhanced activity. Cheddar cheese was exclusively manufactured with 2% inoculum of proteinase negative cultures compared to 1.5% usage of the proteinase positive paired strains. Cheese quality and cheese making times were normal. Over 4200 consecutive vats of Cheddar cheese were made in 1982 employing one pair of proteinase positive culture. Acid control and cheese quality were improved. The cheese making times were more uniform. Smaller inocula volumes could successfully be used for bulk starter in cheese plants utilizing pH controlled starter propagation. A needle/syringe system for inoculating starter tanks provided better protection against contamination during inoculation.

We explored using de-oiled algal biomass (algal cake) as a low-value substrate for production of lactic acid in fermentations with Lactobacillus casei, and strategies for increasing lactic acid production at low pH. L. casei 12A algal cake (AC) fermentations showed carbohydrate and amino acid availability limit growth and lactic acid production. These nutritional requirements were effectively addressed with enzymatic hydrolysis of the AC using α-amylase, cellulase, and pepsin. Producing 0.075 g lactic acid per g AC from AC digested with all three enzymes. We explored heterologous expression of the cellulase gene (celE) from Clostridium thermocellum and the α-amylase gene (amyA) from Streptococcus bovis in L. casei 12A. Functional activity of CelE was not detected, but low-level activity of AmyA was achieved, and increased > 1.5-fold using a previously designed synthetic promoter. Nonetheless, the improvement was insufficient to significantly increase lactic acid production. Thus, substantial optimization of amyA and celE expression in L. casei 12A would be needed to achieve activities needed to increase lactic acid production from AC. We explored transient inactivation of MutS as a method for inducing hypermutability and increasing adaptability of L. casei 12A and ATCC 334 to lactic acid at low pH. The wild type cells and their ΔmutS derivatives were subject to a 100-day adaptive evolution experiment, followed by repair of the ΔmutS lesion in representative isolates. Growth studies at pH 4.0 revealed that all four adapted strains grew more rapidly, to higher cell densities, and produced significantly more lactic acid than untreated wild-type cells. The greatest increases were observed from the adapted ΔmutS derivatives. Further examination of the 12A adapted ΔmutS derivative identified morphological changes, and increased survival at pH 2.5. Genome sequence analysis confirmed transient MutS inactivation decreased DNA replication fidelity, and identified potential genotypic changes in 12A that might contribute to increased acid lactic acid resistance. Targeted inactivation of three genes identified in the adapted 12A ΔmutS derivative revealed that a NADH dehydrogenase (ndh), phosphate transport ATP-binding protein PstB (pstB), and two-component signal transduction system (TCS) quorum-sensing histidine kinase (hpk) contribute to increased acid resistance in 12A.