Purification and characterization of angiotensin I-converting enzyme inhibitors from sour milk

The inhibitory activity of angiotensin I-converting enzyme in milk increased during fermentation with the Calpis sour milk starter containing Lactobacillus helveticus and Saccharomyces cerevisiae. Two kinds of peptides inhibitory to angiotensin I-converting enzyme were purified from the sour milk by using four-step HPLC. The amino acid sequences of these inhibitors were identified as Val-Pro-Pro and Ile-Pro-Pro. The concentrations of peptides providing 50% inhibition of angiotensin I-converting enzyme were 9 and 5 microM, respectively. Most of the inhibitory activity in sour milk was attributed to these two peptides.

[Ecological treatment of bacterial vaginosis]

Ecological treatment of bacterial vaginosis with a Lactobacillus (yoghurt) was studied, and the following results were obtained. 1. A total of 11 women aged 20 to 60 with bacterial vaginosis were treated with intravaginal application of 5 ml of commercial yoghurt (pH 4.3 +/- 0.2). The effect of the treatment was evaluated 3 days after administration by monitoring the vaginal discharge and bacteriological assessment. 2. The clinical improvement was evaluated and the decreases of vaginal discharge and vaginal redness were significant and vaginal pH was lowered significantly also (P < 0.05). In the vaginal discharge 29 strains of bacteria were detected, but 3 days after administration, all 14 strains of Gram-negative bacteria disappeared. As for the overall bacteriological effects, 6/11 cases (54.5%) were eradicated. 3 cases were partly eradicated, 2 cases were replaced. These findings indicated that the Lactobacillus therapy was effective in both clinical and bacteriological responses.

The effect of mixtures of Lactobacillus spp. on the survival of enterotoxigenic Escherichia coli in in vitro continuous culture of porcine intestinal bacteria

Mixtures of strains of Lactobacillus spp., two of strains inhibitory to growth of the porcine enteropathogen Escherichia coli O149: K88ac: K91 in a co-culture screen, and one of strains with no effect on this pathogen, were examined to determine their effects on the retention of this pathogen in an in-vitro continuous culture system designed to maintain a representation of the porcine ileal microflora. Strains effective in co-culture also increased the rate of decline of the pathogen in the continuous culture. The inhibitory effect exceeded the displacement effect observed with non-inhibitory strains.

The role of oral administration of oatmeal fermented by Lactobacillus reuteri R2LC on bacterial translocation after acute liver failure induced by subtotal liver resection in the rat

BACKGROUND

Previous experimental studies showed that a disturbed ecology of the enteric bacterial population might contribute to the occurrence of bacterial translocation from the gut in acute liver failure (ALF).

METHODS

In the present study the effects of oral administration of exogenous Lactobacillus reuteri R2LC and oat fiber on bacterial overgrowth and translocation and on enterocyte protein contents were investigated in rats with ALF induced by subtotal liver resection. The oatmeal soup base was anaerobically inoculated with L. reuteri R2LC and fermented for 15 h. The animals were then fed with fermented or unfermented oatmeal or saline daily for 6 days before the experimental procedure.

RESULTS

The incidence of bacterial translocation to the systemic circulation was nil and 17% in rats subjected to sham operation with saline or 90% hepatectomy with fermented oatmeal, respectively, and 80-90% and 34-50% in rats subjected to hepatectomy with saline or unfermented oatmeal. One rat treated with fermented oatmeal had positive bacterial growth in mesenteric lymph nodes (MLN), which was significantly lower than in hepatectomized rats with saline or unfermented oatmeal (80-100% and 50-67%). No significant differences was demonstrable between hepatectomized animals with oral administration of fermented or unfermented oatmeal as compared with sham-operated rats. The number of anaerobic bacteria, Gram-negative anaerobes, and Lactobacillus decreased significantly, and the number of Escherichia coli increased in the distal small intestine and colon in hepatectomized animals with saline or unfermented oatmeal, as compared with animals subjected to sham operation or hepatectomy with fermented oatmeal.

CONCLUSIONS

The occurrence of bacterial translocation from the gut in 90% hepatectomy-induced ALF could be prevented by fermented oatmeal, which implies possibilities for biologically balancing the enteric bacterial ecology.

[Cytokines, immunostimulation and lactic enzymes]

On the basis of numerous experimental studies the authors advance the hypothesis of the use of lactoferments for immunomodulating purposes. This entails using a traditional and innocuous method for infantile prophylaxis and therapy, (adapted for immunodepressive and even iatrogenic syndromes) which might be assigned a new role through modern, large-scale experimental research.

Production variables and nutrient retention in single comb White Leghorn laying pullets fed diets supplemented with direct-fed microbials

Two experiments were carried out for six and seven 28-d periods, respectively, with DeKalb XL Single Comb White Leghorn laying pullets to ascertain the effect of feeding 1,100 mg Lactobacillus (Lacto)/kg diet (ppm) and 2,200 ppm Lacto diets, and the supplementation of these diets with 1 and 3% fat, on layer performance and nitrogen, calcium, and phosphorus retention. The dietary treatments were corn-soybean meal (C-S) control, C-S plus condensed cane molasses solubles (CCMS)-1,100 ppm Lacto (4.4 x 10(7) cfu/mg Lacto), and C-S plus CCMS-2,200 ppm Lacto (8.8 x 10(7) cfu/mg Lacto) without fat (Experiment 1) and without and with 1 and 3% supplemental fat to each Lacto level (Experiment 2). In both experiments, layers fed the 1,100 ppm Lacto diets had better (P < .05) hen-day production, daily feed consumption, egg mass, egg weight, egg size, and feed conversion than layers fed diets without Lacto. Egg mass, interior egg quality, and feed conversion (Experiment 1), mean body weight gains, and nitrogen, calcium, and phosphorus retention (Experiment 2) were further improved (P < .05) with feeding 2,200 ppm Lacto diets. Feeding Lacto diets with 1% fat provided (P < .05) larger eggs and better (P < .05) nitrogen and phosphorus retention, whereas 3% fat decreased (P < .05) feed consumption and nutrient retention and improved (P < .05) feed conversion and body weight gain. Positive correlations between Lacto diets and nitrogen and calcium retentions, daily feed consumption, and egg size were observed. Feeding 1,100 ppm Lacto diets to layers stimulated appetite and improved egg production, egg mass, egg weight, egg size, and feed conversion. Addition of fat to Lacto diets reduced daily feed consumption and provided better feed conversion, egg masses, egg sizes, body weight gains, and nutrient retentions.

Performance of single comb White Leghorn layers fed corn-soybean meal and barley-corn-soybean meal diets supplemented with a direct-fed microbial

An experiment was conducted with Single Comb White Leghorn (SCWL) layers to determine the effect of feeding either corn-soybean meal (C-S) or barley-corn soybean meal (B-C-S) diets with or without condensed cane molasses solubles (CCMS) or with or without CCMS-1,100 mg Lactobacillus (Lacto)/kg (ppm) diet on performance, nutrient retentions, digesta passage rate, and histological changes of the gastrointestinal (GI) tracts. Six dietary treatments were fed for eight 28-d periods and consisted of C-S (control), C-S + CCMS, C-S + CCMS-1,100 ppm Lacto (4.4 x 107 cfu/mg Lacto), B-C-S (control), B-C-S + CCMS, and B-C-S + CCMS-1,100 ppm Lacto. The CCMS served as the carrier for the Lacto, and the CCMS-Lacto premix (55 g Lacto/kg) was incorporated at 2% of the diet. Lactobacillus supplementation in C-S diets improved (P < .05) egg weight, egg mass, egg size, and body weight gains, and in B-C-S diets improved body weight gains. There were no differences in feed consumption, feed conversion, internal egg quality, and egg specific gravity among the dietary treatments. Passage rates of digesta were increased (P < .05) when either C-S or B-C-S layer diets were supplemented with Lacto. Lactobacillus supplementations of the C-S and B-C-S diets increased (P < .05) fat and calcium, and fat, phosphorus, copper, and manganese retentions, respectively. Increased cellularity of Peyer's patches in the ileum indicated a stimulation of the mucosal immune system that responds to antigenic stimuli by secreting immunoglobulin (IgA).

Phytase activity, phosphorus and calcium retention, and performance of single comb White Leghorn layers fed diets containing two levels of available phosphorus and supplemented with direct-fed microbials

The presence of phytase activities in condensed cane molasses solubles (CCMS) and CCMS-Lactobacillus (Lacto) were determined. Single Comb White Leghorn layers were fed .25 and .45% available P (AP) diets supplemented with CCMS and CCMS-Lacto for nine 28-d periods to determine phytase activities of the gastrointestinal (GI) tract contents and intestine, liver, and pancreatic tissues, the GI tract pH, the P and Ca retention, and layer performance. Six dietary treatments were corn-soybean (C-S) control, C-S+CCMS, and C-S+CCMS-1,100 mg Lacto/kg diet (ppm) [4.4 x 10(7) cfu/mg Lacto] each with .25 and .45% AP. The CCMS were used as a carrier for the Lacto, and the CCMS and CCMS-Lacto premix were incorporated at 2% of the diets. Phytase activity was much higher in CCMS-Lacto premix than in CCMS. Phytase activities of the crop contents were higher with the CCMS-Lacto diets regardless of the AP level. Intestinal phytase activity was higher with the .45% AP CCMS-Lacto diet than the unsupplemented .45% AP diets. Lactobacillus supplementation did not stimulate phytase activities in the intestinal contents or liver and pancreatic tissues. The pH of the crop and intestinal contents were much lower for the Lacto-fed layers than the layers fed unsupplemented diets regardless of dietary AP levels. No differences in Ca retentions were observed with Lacto supplementation regardless of the dietary AP levels. However, higher P retentions were observed with the Lacto supplementation in the .25% AP diet. Layers fed .25 and .45% AP Lacto-supplemented diets had lower hen-day egg production, poorer feed conversion value, consumed slightly more feed, produced less egg mass, and laid larger eggs than the layers fed .25 and .45% AP unsupplemented diets. Lacto supplementation to .25% AP diet produced eggs with higher specific gravity than the unsupplemented .45% AP diet, but not different from unsupplemented .25% AP diet. Layers fed the .25% AP diets had lower BW gains then layers fed the .45% AP diets regardless of lacto supplementation. Phytase activity was present in the lacto source, and the presence of phytase and Lacto supplementation to a .25% AP diet improved P retention in layers.

[The effect of SolcoTrichovac on the vaginal microflora of patients with a papillomavirus infection associated with a cervical intraepithelial neoplasm]

The microbiological study of vaginal secretions of 39 female patients of reproductive age (20-30 years) with papilloma virus infection associated with cervical intraepithelial neoplasia (CIN) was carried out. Of these patients, 28 with papilloma virus infection associated with CINI-II made up group I and II having this infection associated with CINII made up group 2. Dysbiotic disturbances in vaginal bacterial flora, found in these patients, were manifested by a decrease in the isolation rate and number of the lacto- and bifidobacteria simultaneously with the excessive growth of opportunistic bacteria. The results of the oral administration of Solco-Trichovac are indicative of the effectiveness of this preparation, which was confirmed by the data of clinical and bacteriological studies. Together with an increase in the isolation rate of lacto- and bifidobacteria, the level of the contamination of the cervicovaginal niche with opportunistic and pathogenic bacterial strains decreased. The results thus obtained make it possible to recommend Solco-Trichovac for the complex treatment of with papilloma virus infection associated with CIN.

Effect of roasting and fermentation on viscosity of cereal-legume based food formulas

With the view of preparing semi-liquid weaning foods of high energy content, the influence of roasting (stationary hot air treatment) and fermentation (with natural and pure culture inocula) on the viscosity of maize-sorghum-soya porridges was investigated. Roasting resulted in porridges of significantly higher viscosity (cooked porridge cooled to 40 degrees C). Porridges made from the individual ingredients (maize, sorghum, soya) did not show this behaviour. Natural fermentation of mixed ingredients resulted in lower porridge viscosities (cooked porridge cooled to 40 degrees C, as well as hot-paste peak viscosity) when pH was 5.0-5.5. At lower pH the viscosity of the final porridges increased. Fermentation experiments of individual ingredients inoculated with pure cultures of Lactobacillus plantarum and Candida famata lead to the conclusion that various factors contribute to the effect of fermentation on porridge viscosity. Porridges of minimum viscosity are obtained at pH 5.0-5.5 corresponding with a moderate extent of fermentation. From a consumer safety point of view, it would be preferable to acidify to lower pH values (pH < 4.5). If necessary, viscosity adjustments could be made using malted cereals.

Diarrhea with enteral feeding: prospective reappraisal of putative causes

Our objective was to test, in tube-fed patients whether treatment with antibiotics, the presence of hypoalbuminemia, or the use of hypertonic tube feeding is associated with a higher incidence of diarrhea; how often tube feeding actually causes diarrhea; and whether administration of a Lactobacillus preparation reduces the incidence of diarrhea. Our study design included a randomized, double-blind, placebo-controlled trial of patients on tube feeding for at least 5 days. Stool weights and clinical assessment of bowel function were used as outcome measures. Diarrhea was defined as > 200 g of stool, or three or more liquid stools, in any 24-h period. The tube feeding was considered responsible for diarrhea only when the latter resolved on discontinuation of the feeding. When diarrhea did not resolve, other causes were sought. Of 62 patients enrolled, 41 reached a trial end point. Of these, 34 completed 5 days of feeding without diarrhea, and 7 experienced diarrhea. Although diarrhea was associated with hypoalbuminemia and with protracted treatment with antibiotics, in only 1 subject who had a history of gastric surgery was it caused by tube feeding. The other 6 cases of diarrhea were caused by factors other than tube feeding, mainly drugs administered through the tube. Lactobacillus treatment did not alter the risk of diarrhea. Diarrhea occurs more commonly in tube-fed patients who have low serum albumin levels and have been treated with antibiotics for long periods, but these associations are generally not causal. Hypertonic feeding formulas are not associated with increased risk of diarrhea. Most cases of diarrhea in tube-fed patients are caused by factors extraneous to the tube feeding.

Automated microbiological assay of thiamin in serum and red cells

AIMS

To develop a sensitive, direct, automated method for the measurement of serum and red cell thiamin.

METHODS

A microbiological assay using a chloramphenicol resistant strain of Lactobacillus fermenti as the test organism was developed. Addition of chloramphenicol and cycloheximide to the assay medium suppressed bacterial and yeast contamination and enabled tests to be automated without recourse to aseptic procedures. Evaluation of the assay included precision analysis and estimation of thiamin recovery. Results obtained on red cell extracts were compared with an established colorimetric (thiochrome) method.

RESULTS

Acceptable intrabatch and interbatch precision was obtained and good recovery of thiamin added to serum was obtained. Non-parametric reference ranges based on the results from 505 healthy people were: serum thiamin 11.3-35.0 nmol/l and red cell thiamin 190-400 nmol/l. Results were not age or gender related. The method gave results for red cell thiamin which were significantly higher than those obtained with an established thiochrome method.

CONCLUSIONS

This automated microbiological assay is sensitive to 2.0 nmol/l of thiamin and allows tests to be set up at the rate of 100 per hour and after 20-22 hours allows incubation results to be read at 60 per hour. The method has proved reliable, suitable for the assay of large numbers of samples, and relatively inexpensive to perform.

[State of intestinal microbiocenosis and its correction in pregnancy women living under conditions of increased radiation pollution]

The contents of the large intestine were investigated bacteriologically in 44 pregnant women at the pregnancy term of 27-28 weeks living in the areas contaminated with radionuclides at a concentration of 15-40 C/km2. It was found that in 9.6 per cent of the women the intestinal microbiocenosis was within the normal and in 19.1 per cent there was detected marked dysbacteriosis. In the other women compensated or subcompensated intestinal dysbacteriosis was recorded. The state of the large intestine microbiocenosis in the pregnant women did not depend on urogynecological or infectious diseases in the case histories. The prophylactic treatment with eubiotics (bifidumbacterin per rectum and lactobacterin intravaginally) aimed at the correction of the impaired microbiocenosis had a favourable effect which did not depend on urogynecological or infectious diseases in the case histories. After the completion of the prophylaxis course with the eubiotics some indices improved but the percentage of the pregnant women isolating colibacilli with the properties of virulence increased.

[Pathological study of enamel caries produced by oral bacteria in vitro]

The authors used the bacterial culture method to study early enamel caries-like lesions in vitro. Pathologic changes in the lesions were observed under polarized light microscope and scanning electron microscope. The results showed that this method could simulate the destructive procedures in carious development. The destructive way and pathologic changes of the caries-like lesions were very similar to those of natural caries. Under microscope, the ultrastructures of the relatively intact layer of the enamel surfaces were already changed. The prisms in the enamel surfaces were destroyed, and dissolved to form small pores. The pores could be an important path of the carious development.

Successful treatment of early infective endocarditis and mediastinitis in a heart transplant recipient

We report a case of bacterial endocarditis in a heart transplant recipient that was diagnosed 6 weeks after operation when a transesophageal echocardiogram revealed vegetations on both sides of the atrial septum. The patient also had postoperative mediastinitis and pericarditis. He underwent two mediastinal explorations, pericardiectomy, and 22 weeks of antibiotics and is free of infection 1 year after transplantation. We presume that the source of infection was contamination of the donor heart by the donor's right lung, which was harvested en bloc with the heart.

Microbiological evaluation of jejunal aspirates and faecal samples after oral administration of bifidobacteria and lactic acid bacteria

A double-blind placebo controlled investigation was carried out to study the effect of peroral colonization. Human volunteers were given mixtures of bifidobacteria and lactic acid bacteria. Measurements were made over a 1 week treatment period and for another week after the end of the treatment. Two different bacteriological preparations were used, one consisted of Enterococcus faecium and Bifidobacterium longum (a total of 6.4 x 10(8) cfu d-1); the other consisted of Lactobacillus acidophilus, Bif. bifidum, Lact. delbrueckii ssp. bulgaricus, and Streptococcus thermophilus (a total of 9 x 10(9) cfu d-1). Together with a placebo preparation, they were given to 24 healthy controls (eight in each group). Microbiological examinations of jejunal aspirates showed that viable counts of most species were below the detection limit. However, the test preparation containing Ent. faecium and Bif. longum significantly reduced the anaerobe: aerobe ratio in faeces by a factor of three during treatment (P = 0.03), and increased it by a factor of 30 during the following week (P < 0.02). This study shows that peroral administration of certain bacterial cultures may affect the distal intestinal microflora.

Lactobacillus feeding reduces endotoxemia and severity of experimental alcoholic liver (disease)

We have previously shown a relationship between plasma endotoxin levels and severity of alcoholic liver injury in the intragastric feeding rat model. We attempted to reduce both circulating endotoxin and liver injury in this model by administering a lactobacillus strain (species GG) which survives for prolonged periods in the gastrointestinal tract. Male Wistar rats were fed ethanol and liquid diet containing corn oil (CO+E). Another group of animals (CO+E+L) received the diet containing ethanol plus a daily bolus of lactobacilli GG concentrate (10(10) CFU). All animals were sacrificed after one month. All animals had plasma endotoxin measurements and evaluation of severity of pathologic changes in the liver. The weight gain and blood alcohol levels were similar in both groups. The mean +/- SE of the pathology score was significantly higher (3.4 +/- 0.85) in the CO+E group compared to the CO+E+L group (0.5 +/- 0.3, P < 0.01). The virtual absence of pathologic changes in the latter group was accompanied by significantly lower endotoxin levels (8.4 +/- 2.9 pg/ml in CO+E+L group vs 48.3 +/- 7.8 pg/ml in CO+E group, P < 0.01). Feeding of strains of lactobacilli that survive in the gastrointestinal tract reduces endotoxemia and alcohol-induced liver injury in the rat. Lactobacillus species GG provides a potential nontoxic form of therapy for both endotoxemia and alcoholic liver disease.

Lactobacillus strain GG supplementation decreases colonic hydrolytic and reductive enzyme activities in healthy female adults

The effects of yogurt containing viable Lactobacillus strain GG (L. GG) and/or fiber supplements on fecal enzyme activities (beta-glucuronidase, nitroreductase, beta-glucosidase, glycocholic acid hydrolase, urease) and on bacterial metabolites in urine (phenol, p-cresol) were studied in 64 females, 20-41 y old. The subjects were randomly divided into three groups: the first group received L. GG yogurt (2 x 150 mL/d, containing 10(11) colony-forming units (cfu)/L of L. GG), the second group received L. GG yogurt and a rye fiber product (30 g/d, equivalent to 9 g fiber/d), and the third group received placebo yogurt (pasteurized) and fiber. The supplementation period lasted 4 wk, with a preceding 2-wk baseline period and a 2-wk follow-up period. The mean fecal count of L. GG was approximately 10(6) cfu/g feces during the supplementation, and L. GG persisted in the fecal samples of 28% of the subjects for 2 wk after supplementation. L. GG yogurt alone or with fiber significantly decreased fecal beta-glucuronidase, nitroreductase and glycocholic acid hydrolase activities. These enzyme activities returned to baseline levels during the follow-up period. beta-Glucosidase and urease activities were not altered significantly during the study. The addition of fiber to L. GG and placebo yogurt had no effect on the enzymic activities. Urinary excretion of p-cresol decreased significantly in groups receiving L. GG. These data demonstrate that L. GG can modify the colonic environment with possible health effects.

A comparison of two transport media for saliva and subgingival samples

This study has shown that microorganisms associated with caries (mutans streptococci, lactobacilli) and marginal periodontitis (Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans) in pure culture can be stored in VMGA or reduced transport fluid and be recovered sufficiently after 24 h. Sufficient recovery after 24 h of mail transport was also obtained in 37 saliva samples obtained from adults and 80 subgingival samples from a group of patients before and 3, 6 and 15 months after periodontal treatment. The samples transported in VMGA III showed in comparison to the samples transported in reduced transport fluid a higher recovery rate as well as a higher percentage of the total viable count for investigated anaerobic species. This was explained by the different composition of the two media and also by the gel consistency of VMGA III, which maintains a low redox-potential even during transport after transferring a sample into the medium. In a few samples aerobic bacteria increased in both media.

Characterization of a prolate-headed bacteriophage of Lactobacillus delbrueckii subsp. lactis, and its DNA homology with isometric-headed phages

A new Lactobacillus delbrueckii subsp. lactis bacteriophage, JCL 1032, was characterized. JCL 1032 had a small, elongated prolate head, and a long non-contractile tail with cross-bars. The restriction map of JCL 1032 genome was constructed with five endonucleases. The genome was 45.8 kb in size, and it had cohesive ends (cos). Molecular masses of the phage structural proteins were also determined. JCL 1032 showed DNA homology with morphologically dissimilar, isometric-headed phages of Lb. delbrueckii (subsp. lactis and subsp. bulgaricus) when analyzed by Southern hybridization. Although in general JCL 1032 was only distantly related to isometric-headed phages, there were also a few short highly homologous (minimal homology 84%) DNA regions.

Molecular comparison of the structural proteins encoding gene clusters of two related Lactobacillus delbrueckii bacteriophages

Virulent phage LL-H and temperate phage mv4 are two related bacteriophages of Lactobacillus delbrueckii. The gene clusters encoding structural proteins of these two phages have been sequenced and further analyzed. Six open reading frames (ORF-1 to ORF-6) were detected. Protein sequencing and Western immunoblotting experiments confirmed that ORF-3 (g34) encoded the main capsid protein Gp34. The presence of a putative late promoter in front of the phage LL-H g34 gene was suggested by primer extension experiments. Comparative sequence analysis between phage LL-H and phage mv4 revealed striking similarities in the structure and organization of this gene cluster, suggesting that the genes encoding phage structural proteins belong to a highly conservative module.

Isolation and partial characterization of three rumen Lactobacillus plantarum bacteriophages

The first isolation of Lactobacillus plantarum bacteriophages from ruminal fluid is reported. Three bacteriophages were characterized on the basis of plaque morphology, host ranges, stability, electron microscopic morphology and DNA restriction endonuclease digestion patterns. They formed clear plaques and are placed in group A of Bradley's scheme and have identical host ranges. Bacteriophages were stable to urea and chloroform. They were relatively thermostable but partially inactivated by rumen fluid and by acetate. DNA restriction analysis showed that phage L20 had different numbers of cleavage sites in comparison with the next two phages.