Nonfat Skim Milk Research Articles

Distinct Gut Microbiota and Serum Metabolites in Response to Weight Loss Induced by Either Dairy or Exercise in a Rodent Model of Obesity.

Energy imbalance is a primary cause of obesity. While the classical approach to attenuate weight gain includes an increase in energy expenditure through exercise, dietary manipulation such as the inclusion of dairy products has also been proven effective. In the present study, we explored the potential mechanisms by which dairy and exercise attenuate weight gain in diet-induced obese rats. Male Sprague-Dawley rats were fed a high fat, high-sugar (HFHS) diet to induce obesity for 8 weeks. Rats were then further grouped into either control (HFHS + casein) or dairy diet (HFHS + nonfat skim milk) with and without treadmill exercise for 6 weeks. Serum and fresh fecal samples were collected for gut microbiota, serum metabolomics, and metallomics analysis. Diet and exercise resulted in distinct separation in both gut microbiota and serum metabolite profiles. Most intriguingly, obesogenic bacteria including Desulfovibrio and Oribacterium were reduced, and bioactive molecules such as mannose and arginine were significantly increased in the dairy group. Correlations of at least six bacterial genera with serum metal ions and metabolites were also found. Results reveal distinct impacts of dairy and exercise on the gut microbiota and in the modulation of circulating metabolites with the former primarily responsible for driving microbial alterations known to attenuate weight gain.

Novel pendrin inhibitor attenuates airway hyperresponsiveness and mucin expression in experimental murine asthma

Novel pendrin inhibitor attenuates airway hyperresponsiveness and mucin expression in experimental murine asthma

Screening of freeze-dried protective agents for the formulation of biocontrol strains, Bacillus cereus AR156, Burkholderia vietnamiensis B418 and Pantoea agglomerans 2Re40

The effects of different freeze-drying protective agents on the viabilities of biocontrol strains Bacillus cereus AR156, Burkholderia vietnamiensis B418 and Pantoea agglomerans 2Re40 were investigated. Several concentrations of protective and rehydration media were tested to improve the survival of biocontrol agents after freeze-drying. The subsequent survival rates during storage and rehydration media of freeze-dried biocontrol strains were also examined. The results indicated that cellobiose (5%) and d-galactose (5%) gave maximum viability of strains Bu. vietnamiensis B418 and P. agglomerans 2Re40 (98 and 54·3% respectively) while the perfect one (100%) of strain B. cereus AR156 was obtained with sucrose (5%) during freeze-drying, and the highest survival of the three strains was reached when they were rehydrated with 10% nonfat skim milk. In the following storage, the survival rates showed that B. cereus AR156 could still reach 50% after 12 months. This study showed that freeze-drying could be used to stabilize cells of these three biocontrol strains. Further studies should focus on the scale-up possibilities and formulation development.

Peroxisome Proliferator-activated Receptor α Is Responsible for the Up-regulation of Hepatic Glucose-6-phosphatase Gene Expression in Fasting and db/db Mice

Glucose-6-phosphatase (G6Pase) is a key enzyme that is responsible for the production of glucose in the liver during fasting or in type 2 diabetes mellitus (T2DM). During fasting or in T2DM, peroxisome proliferator-activated receptor α (PPARα) is activated, which may contribute to increased hepatic glucose output. However, the mechanism by which PPARα up-regulates hepatic G6Pase gene expression in these states is not well understood. We evaluated the mechanism by which PPARα up-regulates hepatic G6Pase gene expression in fasting and T2DM states. In PPARα-null mice, both hepatic G6Pase and phosphoenolpyruvate carboxykinase levels were not increased in the fasting state. Moreover, treatment of primary cultured hepatocytes with Wy14,643 or fenofibrate increased the G6Pase mRNA level. In addition, we have localized and characterized a PPAR-responsive element in the promoter region of the G6Pase gene. Chromatin immunoprecipitation (ChIP) assay revealed that PPARα binding to the putative PPAR-responsive element of the G6Pase promoter was increased in fasted wild-type mice and db/db mice. These results indicate that PPARα is responsible for glucose production through the up-regulation of hepatic G6Pase gene expression during fasting or T2DM animal models.

Drying of Conidia of Penicillium oxalicum, a Biological Control Agent against Fusarium Wilt of Tomato

AbstractThe effects of freeze drying, spray drying, and fluid bed drying on the viability of Penicillium oxalicum conidia were compared. Conidia of P. oxalicum can be dried by fluid bed drying and freeze drying maintaining 100% viability after both processes, but protective additives must be added for obtaining this viability in the case of freeze drying. The best viabilities were obtained after freeze drying with non‐fat skim milk (NFSM) + Tween 20, NFSM + peptone and NFSM + sucrose. However, NFSM + glycerol had only a 0.5% viability after freeze drying. Freeze‐dried P. oxalicum conidia with or without additives did not maintain viability over time at room temperature, while conidia dried in a fluidized bed drier had a 40–50% viability after 180 days of storage in these conditions. Penicillium oxalicum conidial viability after spray‐drying was lower than 20%. Penicillium oxalicum conidia dried by fluid bed drying were effective in reducing the incidence of Fusarium wilt of tomato under glasshouse and field conditions.

Effectiveness of Thermal Treatments and Biocides in the Inactivation of Argentinian Lactococcus lactis Phages

The thermal and chemical resistance levels of four autochthonal bacteriophages of Lactococcus lactis subsp. lactis, isolated from cheese processes, was investigated. The times required to obtain 99% inactivation of phages (T99) at 63 and 72°C in three suspension media (M17 broth, reconstituted commercial nonfat skim milk, and Tris magnesium gelatin buffer) were determined. Thermal resistance was dependent on the phage studied, and the results of this study demonstrate that pasteurization treatments used in dairy industries may leave viable viral particles in milk. It was possible to determine that M17 broth was generally the least protective medium, while phosphate buffer was the most protective one. Peracetic acid (0.15%, vol/vol) was the most effective viricidal agent, with exposures of 5 min being sufficient to inactivate high-titer phage suspensions (>106 PFU/ml). To achieve total inactivation (<10 PFU/ml) of viral suspensions, sodium hypochlorite was effective at 100 ppm for only two phages, while the other two phages needed concentrations of 200 and 300 ppm. Ethanol at concentrations of 100 and 75% proved to be very efficient in inactivating phages, but isopropanol was not effective against them.

Identification of sites in the second exomembrane loop and ninth transmembrane helix of the mammalian Na+/H+ exchanger important for drug recognition and cation translocation.

Mammalian Na(+)/H(+) exchanger (NHE) isoforms are differentially sensitive to inhibition by several distinct classes of pharmacological agents, including amiloride- and benzoyl guanidinium-based derivatives. The determinants of drug sensitivity, however, are only partially understood. Earlier studies of the drug-sensitive NHE1 isoform have shown that residues within the fourth membrane-spanning helix (M4) (Phe(165), Phe(166), Leu(167), and Gly(178)) and a 66-amino acid segment encompassing M9 contribute significantly to drug recognition. In this report, we have identified two residues within M9, one highly conserved (Glu(350)) and the other non-conserved (Gly(356)), that are major determinants of drug sensitivity. In addition, residues in the second exomembrane loop between M3 and M4 (Gly(152), Phe(157), and Pro(158)) were also found to modestly influence drug sensitivity. A double substitution of crucial sites within M4 and M9 of NHE1 with the corresponding residues present in the drug-resistant NHE3 isoform (i.e. L167F/G356A) greatly reduced drug sensitivity in a cooperative manner to levels nearing that of wild type NHE3. The above mutations did not appreciably affect Na(o)(+) affinity but did markedly decrease the catalytic turnover of the transporter. These data suggest that specific sites encompassing M4 and M9 are critical determinants of both drug recognition and cation translocation.

Effect of protective agents, rehydration media and initial cell concentration on viability of Pantoea agglomerans strain CPA-2 subjected to freeze-drying

The effect of initial cell density, protective agents and rehydration media on the viability of biocontrol agent Pantoea agglomerans CPA-2 when subjected to freeze-drying was studied. Several additives were tested as protective agents against freeze-drying injury. Maximum viability of the bacterial cells was obtained with disaccharides (survival levels > 60%). Freeze-dried samples were rehydrated with several media; the highest percentage viability was obtained with 10% non-fat skim milk (100%+). The effect of initial bacterial load on the final recovery was dependent on protectant but not on rehydration media. Sucrose was an effective protectant when a high initial concentration (10(10) cfu ml(-1) was used; the opposite occurred with non-fat skim milk. The use of 10(10) cfu ml(-1) as an initial concentration, sucrose as a protectant and non-fat skim milk as a rehydration medium enabled 100% of P. agglomerans viability to be conserved after freeze-drying. Results suggest the possibility of achieving a good formulation system for the studied biocontrol agent with a high number of viable cells to be used toward pathogens, which is desirable for the industrial development of the product.

Thermal and Chemical Inactivation of Indigenous Streptococcus thermophilus Bacteriophages Isolated from Argentinian Dairy Plants

Thermal and chemical resistance of five autochthonal bacteriophages of Streptococcus thermophilus, isolated from Cuartirolo cheese wheys and yogurt, was investigated. Times to obtain 99% inactivation of phages (T99)at63°C and 72°C in three suspension media (enriched tryptic soy broth, reconstituted commercial nonfat skim milk, and tris magnesium gelatin buffer) were determined. The thermal resistance was dependent on the phages studied but not detectable counts (<10 PFU/ml) were only achieved by heating at 90°C during 5 min. The data obtained for the three assayed media did not permit verifying significant differences among them. Sodium hypochlorite (100 ppm) provided a fast inactivation of bacteriophage particles (<10 PFU/ml after 5 min). Ethanol, at concentrations of 75% and 100%, was also effective for phage destruction. Isopropanol was slightly less effective than ethanol at the same concentrations. Peracetic acid (0.15%) was also a very effective agent for phage inactivation. The results showed that these autochthonal bacteriophages were not completely inactivated neither by normal pasteurization treatments nor by some biocides commonly used in disinfection, except sodium hypochlorite and peracetic acid. The practical implications of these findings have pointed out the necessity of recognizing the importance of establishing adequate conditions to assure effective thermal and chemical treatments in dairy plants and laboratory environments.

Nutrient Intake and Eating Patterns of Elite and World/Olympic Figure Skaters

The nutritional intakes and eating patterns of elite, world and Olympian figure skaters were evaluated. Three day diet records, weights and heights were collected. Participants included 20 females 17.7 ± 8 years of age and 18 males 19.5 ± 3.6 years of age. Average weight and height for females was 107.5 ± 15.0 pounds, 5.1 ± .2 feet and for males, 146.1 ± 17.7 pounds, 5.6 ± .2 feet. Average daily caloric intakes were 1473 ± 506Kcal for females and 2795 ± 1152Kcal for males. Percentage of calories from carbohydrate, protein and fat for females were 59, 18 and 25 respectively. Percentage of calories from carbohydrate, protein and fat for males were 55, 16 and 30 respectively. Distribution of calories for breakfast, lunch, dinner and snacks for females vs males was 310 ± 196 vs. 477 ± 274, 388 ± 245 vs. 875 ± 529, 503 ± 281 vs. 824 ± 558, and 270 ± 320 vs. 618 ± 784 respectively. For females, caloric intake was below the norm for their age group, however males were within 93% of their age group. Males consumed more calories from snack occasions vs. females. The most frequently consumed snacks for both females and males were water, fruit, nonfat skim milk, diet sodas, powerbars and fruit bars. Females obtained a higher percentage of calories at dinner(34) vs. males(29). The caloric density of fat by meal occasion was higher for males vs. females at lunch(.04 vs. .03), dinner(.04 vs. .03) and snacking(.03 vs. .02), respectively. The low caloric intake of the female skaters may be increased by raising the consumption of their fat intake. Although the skaters as a group were consuming three meals and snacks it's important to evaluate the individual eating patterns and nutrient distribution to develop a program to meet their nutritional and performance needs.

Characterization of natural isolate Lactobacillus acidophilus BGRA43 useful for acidophilus milk production.

Lactobacillus acidophilus BGRA43 was selected from a set of human origin isolates of Lact. acidophilus strains for the highest growth rates and antagonistic effect against both Gram-positive and Gram-negative bacteria. The strain BGRA43 also exhibited an inhibitory effect on the growth of Clostridium sporogenes. Inhibition of this strain seems to be due to lactic acid production rather than hydrogen peroxide or bacteriocin. Growth of Lact. acidophilus BGRA43 in non-fat skim milk for 6 h at 37 degrees C resulted in a lowering of the pH value to 4.53. Besides the fast acidification, this strain generated a high viscosity of skim milk. These characteristics make the strain BGRA43 attractive for acidophilus milk production. Lactobacillus acidophilus BGRA43 produces an extracellular proteinase. Whole cells efficiently degraded casein for 3 h at 37 degrees C especially alpha- and beta-casein fractions. Total DNA isolated from the strain BGRA43 did not show any hybridization with lactococcal proteinase probes indicating that this strain produces a distinctive proteinase.

Activity-loss kinetics of freeze-dried lactic acid starter cultures

Lactic acid starter cultures were freeze-dried in whey and nonfat skim milk (NFSM) suspending media with varying amounts of glycerol, adonitol, and sucrose as the additives. Generally additives had different cryoprotective effects in NFSM and whey media. There was also an optimum cryoprotective additive concentration where viability and activity were protected best. The best results were obtained with freeze-dried L. bulgaricus with 0.29 m sucrose, 0.75 m adonitol, or 0.75 m glycerol in whey medium. Similarly, the best protection was obtained with S. thermophilus with 1 m , 0.5 m , and 0.75 m adonitol in NFSM medium and 1 m adonitol in whey medium. Viability loss during freeze-dried storage was modeled with a first-order kinetic expression in viable cell concentration. Activity loss was modeled with a first-order kinetic expression in activity. The major cause of activity loss was death of the microorganisms. Activity loss and viability loss were parallell during storage; an occasional deviation from such a parallel trend occurred due to the presence of injured microorganisms that did not produce lactic acid.

Effect of the rehydration medium on the recovery of freeze-dried lactic acid bacteria.

Sixteen cultures of lactic acid bacteria were freeze-dried in 10% nonfat skim milk plus 0.75 M adonitol and rehydrated by using different rehydration media. Marked variations in their capacity to repair cellular damage after freeze-drying were observed among the species and strains under consideration.

Improved Reverse Phase Liquid Chromatographic Determination of Vitamins A and D in Fortified Milk

A method for determination of vitamins A, D2, and D3 on the same 6 mL sample of fortified milk is described. A special indicator permits selection from the cleanup column of a fraction that contains all vitamin D and is free of cholesterol interference for final measurement by reverse phase liquid chromatography. Conservation of analyst's time and expensive solvents results from the relatively small sample processed. The average recoveries and standard deviations were, respectively, 94.1% and 4.8 for vitamin D2, 91.1% and 5.2 for vitamin D3, and 92.2% and 2.6 for vitamin A in nonfat skim milk; 86.5% and 9.4 for vitamin D2, and 83.7% and 4.9 for vitamin D3 in homogenized whole milk. Detectable minima are about 100 IU vitamin A/qt and 50 IU vitamin D2 or D3/qt.

Comparative study of the efficiency of some additives in protecting lactic acid bacteria against freeze-drying

Cultures of 14 lactic acid bacteria species were freeze-dried in 10 or 20% non-fat skim milk and in distilled water containing one of the following additives: bovine albumin, glycogen, dextran, polyethylene glycol (PEG) 1000, PEG 4000, PEG 6000, glycerol, β-glycerophosphate, sodium glutamate, asparagine, or cysteine. Each of the potential protective agents tested exhibited marked variations in the protection afforded to different species, none of them was effective for the preservation of viability of thermophilic lactobacilli. However, glycerol provided effective protection for L. leichmannii ATCC 4797 (90% survival), while L. bulgaricus ATCC 11842 reached a viability of 78% with 0.04 M cysteine.