Invitro and Invivo Analysis of Human Milk Lactic Acid Bacteria Isolates for Their Anti-hypercholesterolemia Actions

The aim of this study was to evaluate the cholesterol lowering ability of Lactic Acid Bacteria (LAB) isolated from human breast milk under in vitro and in vivo conditions. Six LAB isolates namely Lacticaseibacillus casei 1A, Lactobacillus gasseri 5A, Enterococcus faecium 2C, Limosilactobacillus fermentum 3D, Pediococcus acidilactici 1C, and Lactiplantibacillus plantarum 7A, were examined for their bile resistance, bile salt hydrolase activity, cholesterol assimilation and viability in cholesterol rich; DeMan Rogosa and Sharpe broth, simulated gastric, small and upper intestinal conditions. During in vivo experiments, two putative LAB isolates were orally gavage to BALB/c mice, fed with normal basal and cholesterol rich (HCD) diets, daily for a period of 4 weeks. Blood serum analysis including total serum cholesterol, triglycerides, high-density and low-density lipoprotein (LDL) cholesterol levels and total fecal LAB counts of the animals were determined. The isolates in study showed bile resistance and bile salt hydrolysis activity, while significant differences (P < 0.05) were seen in their cholesterol assimilation ability. L. gasseri 5A (195.67%) and L. plantarum 7A (193.78%) displayed highest cholesterol removal percentages, respectively. Animals in HCD, fed with L. gasseri 5A and L. plantarum 7A showed decreased levels of total cholesterol and LDL, compared to the control groups. In HCD group liver weight was increased, while fecal LAB counts were decreased. No changes were observed in behavior or body weight in all experimental groups. In conclusion, L. gasseri 5A and L. plantarum 7A isolated from human breast milk demonstrates significant hypocholesterolaemic actions in vitro and in vivo and might be considered a promising candidates for preventing hypercholesterolemia in man and animals.

Anti-Bacterial Activity of Four Distinct Propolis Extracts against P. larvae and M. plutonius; Etiological Agent of American and European Foulbrood Disease of Honeybees

Four different propolis samples obtained from different regions of Iran were evaluated for their antibacterial effects against the bacterial agents responsible for two important honeybee diseases. Paenibacillus larvae (P. larvae) and Melissococcus plutonius (M. plutonius), as the etiological agents of American foulbrood (AFB) and European foulbrood (EFB) diseases, were subjected to propolis ethanolic extracts in the agar well diffusion assay. The minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC) of the antibacterial effects of the samples against the two indicator organisms were determined by the microdilution technique using different concentrations of the propolis extracts. Finally, the synergistic antibacterial actions of the mixed propolis samples were determined, and their MIC and MBC values were recorded. A two-way analysis of variance was used to evaluate correlations among the diameters of the inhibition zones, the bacterial agents, and the propolis extracts. Based on our results, three of the propolis samples showed significant antibacterial effects against P. larvae and M. plutonius during the agar well diffusion assay. Furthermore, the antibacterial capacity of the propolis samples, when mixed in equal proportions, was significantly enhanced, as indicated by the obtained MIC and MBC values. Approximately, 0.02 mg/mL of mixed propolis samples was required for inhibiting the growth of both pathogens. A direct correlation was observed between propolis concentrations and their antibacterial activity. The results of the study are conclusive of the significant antibacterial actions of Iranian propolis samples against the etiological agents of the mentioned honeybee diseases, suggesting their probable use as a safe biological agent to control AFB and EFB diseases.

Propolis: An update on its chemistry and pharmacological applications

Propolis, a resinous substance produced by honeybees from various plant sources, has been used for thousands of years in traditional medicine for several purposes all over the world. The precise composition of propolis varies according to plant source, seasons harvesting, geography, type of bee flora, climate changes, and honeybee species at the site of collection. This apiary product has broad clinical applications such as antioxidant, anti-inflammatory, antimicrobial, anticancer, analgesic, antidepressant, and anxiolytic as well asimmunomodulatory effects. It is also well known from traditional uses in treating purulent disorders, improving the wound healing, and alleviating many of the related discomforts. Even if its use was already widespread since ancient times, after the First and Second World War, it has grown even more as well as the studies to identify its chemical and pharmacological features, allowing to discriminate the qualities of propolis in terms of the chemical profile and relative biological activity based on the geographic place of origin. Recently, several in vitro and in vivo studies have been carried out and new insights into the pharmaceutical prospects of this bee product in the management of different disorders, have been highlighted. Specifically, the available literature confirms the efficacy of propolis and its bioactive compounds in the reduction of cancer progression, inhibition of bacterial and viral infections as well as mitigation of parasitic-related symptoms, paving the way to the use of propolis as an alternative approach to improve the human health. However, a more conscious use of propolis in terms of standardized extracts as well as new clinical studies are needed to substantiate these health claims.

Role of Honey Bee Gut Microbiota in the Control of American Foulbrood and European Foulbrood Diseases

American foulbrood (AFB) and European foulbrood (EFB) are the two most important honey bee brood diseases which impose heavy economic losses to the apiculture industry worldwide by reducing bee population and honey production. Treatment with antibiotics has led to the emergence of antibiotic-resistant strains, calling for alternative safe treatment procedures that could control these diseases. Honey bee gut microbiota is known to affect the overall health of honey bees by enhancing their resistance to a number of diseases via modulation of the immune response and production of different antimicrobial metabolites. The majority of these gut resident bacteria are identified as probiotic bacteria and secure the health of these tiny insects. In the present review, we highlighted the significance of the honey bee gut microbial community and their probiotic potency for the prevention of AFB and EFB diseases in honey bees.

Evaluation of in vitro Anti-Brucella Activity and Chemical Composition of Different Geographically Distinct Propolis from Iran

Brucellosis is one of the most important zoonotic diseases in many regions worldwide. This study aimed to investigate the antimicrobial properties of hydro-ethanolic extracts of propolis (EEP) samples collected from six different regions of Iran against five Brucella melitensis (B. melitensis) clinical isolates causing human brucellosis and an antibiotic-resistant B. abortus vaccinal strain (RB51). Brucella clinical isolates were first carefully identified using conventional molecular typing and Brucella bio-typing methods. Different Brucella strains were then confronted with EEPs using the disk-diffusion agar method to evaluate the antimicrobial activity of each propolis extract. Chemical composition of EEPs was then determined using HPLC-DAD, and the main phenolic compounds were quantified. It was found that all EEPs displayed significant antimicrobial activities against Brucella strains, though to varying extents. All tested clinical strains were susceptible to different EEPs with inhibition zones ranging from 18 to 38 mm diameter. Interestingly, the RB51 vaccine strain was more susceptible to EEP6 (from Markazi province), compared to conventional antibiotics used in the treatment of brucellosis. Substantial differences observed in EEP antimicrobial activity could be due to their distinct botanical origins and chemical compositions as confirmed by our HPLC analysis. The promising inhibitory effect of some propolis preparations against a broad spectrum of Brucella strains points to the need for further studies in the context of systematic clinical investigations and opens up the way for the development of natural complements in support of conventional antibiotic therapy.

In vitro probiotic and safety attributes of Bacillus spp. isolated from beebread, honey samples and digestive tract of honeybees Apis mellifera

Bacillus species isolated from honeybee Apis mellifera gut, honey and bee bread samples were characterized for their in vitro probiotic and safety attributes. Alpha and γ haemolytic cultures were tested for their antibiotic resistance, antibacterial spectrum, acid and bile tolerance, adhesion ability (auto-aggregation, co-aggregation and hydrophobicity) and phenol tolerance. Safety criteria included evaluation of virulence genes and cytotoxicity percentages. Bacillus isolates inhibited both Gram-positive and Gram-negative pathogens including Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis and Streptococcus mutans, while none could inhibit Listeria monocytogenes. Among the isolates, Bacillus subtilis ZH05, ZB03 and ZG025 showed resistance to most of the tested antibiotics and were considered unsafe. B. subtilis (4) and B. licheniformis (1) tolerated acidic pH and bile conditions, never the less were more tolerant in simulated intestinal conditions vis-a-vis gastric conditions. In 0·5% phenol concentrations, B. licheniformis ZH02 showed highest growth, while, B. subtilis ZG029 demonstrated highest auto-aggregation (65 ± 4·6) and hydrophobicity (23 ± 3·6) percentages (P < 0·05). The isolates lacked virulence genes (hblA, hblC, hblD, nhe, cytK and ces), and their cytotoxic percentage on Caco-2 cell lines was ˂15%. Overall, honeybees appear to be a good source of Bacillus species exhibiting typical in vitro probiotic properties, which could be of commercial interest.

Isolation and Purification of Low Molecular Weight Proteins from Culture Filtrate of Mycobacterium Tuberculosis Strain C

In the last couple of years, a number of new and rapid tests for the diagnosis of Tuberculosis (TB) have been developed based on the low molecular weight antigens from Mycobacterium tuberculosis (Mtb) culture supernatant. This study aimed to isolate and purify low molecular weight antigens secreted by Mtb strain C for diagnostic purpose. The secretory proteins from culture filtrate of Mtb were extracted using ammonium sulphate precipitations and sephadex-G50 gel chromatography. The obtained antigen fractions were analyzed for their protein concentrations and approximate molecular weight using Lowry method and SDS-PAGE (12.5%), respectively. DOT-ELISA and Western blot assay was performed to confirm the presence of purified low molecular weight proteins isolated from Mtb using sera from pulmonary tuberculosis patients (polyclonal antibodies). During chromatography, low molecular weight proteins were separated, that was approximately 0.7 mg/ml of the total proteins (1.662 mg/ml). The purified protein fractions in molecular weight range of 14 kDa-41kDa appeared during SDS-PAGE analysis. The chromatographic band fraction in the weight range of 30-41 kDa was identified in the TB patients&amp;rsquo; sera using Western blotting. The low molecular weight proteins in the culture filtrate of Mtb strain C were purified using ammonium sulphate and chromatography. These fractions were confirmed using Western blotting. The obtained results might support the hypothesis that the Mtb culture filtrate antigens could be used as a rapid and sensitive assay for the detection of patients with pulmonary TB.

Designing of Western Blot Technique for Glanders Diagnosing in Iran

Burkholderia mallei is the etiologic agent of glanders. It is difficult to diagnose this zoonotic disease in its early stages. Some methods such as the complement fixation test (CFT) cause some problems for veterinary authorities and financial losses to animal owners due to false-positive results. The mallein test requires appropriate laboratory equipment and skilled personnel. To quickly and accurately diagnose the disease, especially in areas where animals cannot be kept, new methods (such as the Western blot test [WBT]) should be used to identify the disease. This study designed and optimized the Western blot (immunoblot) test using sera from 84 glanderous equids, and the sensitivity and specificity of ELISA and CFT were compared with the WBT. ELISA tests are based on B. mallei antigens whereas a purified lipopolysaccharide-containing B. mallei antigen is used in the WBT. The sensitivity and specificity of the tests were estimated using the cut-off values recommended by the test developers. The WBT and ELISA were significantly more specific than the CFT. The ELISA based on B. mallei antigens was significantly less sensitive than the CFT. Given their comparable sensitivities and specificities, the CFT (95.7%, 98.5%), the WBT (95%, 100%) and the ELISA (85%, 100%) should be further developed. The CFT is still the prescribed technique for serological investigation of equids for trade purposes to certify individual animals without glanders. Therefore, more efforts should be made to further improve and optimize the WBT and ELISA tests.

Combined effect of probiotics and specific immunoglobulin Y directed against Escherichia coli on growth performance, diarrhea incidence, and immune system in calves

Enterotoxigenic Escherichia coli (ETEC) K99 is one of the major pathogens associated with calf diarrhea. The induction of passive immunity in animals by immunoglobulin Y and using probiotics are inexpensive alternatives to antibiotics for the prevention and treatment of a number of bacterial infections, including diarrhea. Hence, the aim of this research was to evaluate the impact of dietary probiotics and ETEC K99-specific egg yolk antibody supplements, alone and in combination with each other, on health and growth parameters, diarrhea incidence and immune stimulation in newborn Holstein calves. One hundred and twenty neonatal calves were allocated randomly into 4 dietary groups (n = 30 per group) received colostrum/milk without any additives (control group), or supplemented with egg yolk powder contained E. coli K99-specific antibody (Ab group; 1 g/day), a commercial probiotic, Hypro-calves (Pro group; 3 g/day), and their combination (Ab+Pro group), from day (d) 1 to d28 of age. Analyses of the growth parameters, feed efficiency, fecal score, and microbiota and immune function were carried out on d0, 14, 21, and 28 of the experiment. Calves in Ab or Ab+Pro group had higher (P < 0.05) average daily gain compared to control and Pro groups during 0-14d. Feed efficiency of calves in Ab and Ab+Pro groups was significantly higher than that in control group during the period of 0-14d; however, no significant differences were observed in 0-28d period. Diarrhea prevalence and fecal score in Ab+Pro group were lower than control group (P < 0.05). Calves in Ab+Pro group had the lowest number of fecal E. coli in comparison to other groups on d28 (P < 0.05). Feeding Ab+Pro supplement increased (P < 0.05) concentrations of blood IgA and serum CD4 compared to the control group. Likewise, calves in Pro group had higher CD4 levels as compared to the control calves (P < 0.05). Serum concentration of interferon-gamma in control group was lower than other groups (P < 0.05). Overall, these data suggest that feeding a combination of probiotic and specific antibody against ETEC to neonate Holstein calves enhances feed efficiency, boosts immunity, and reduces diarrhea prevalence.

Anti-mycotoxigenic properties of probiotic Bacillus spp. in Japanese quails

The current study was conducted to evaluate the anti-mycotoxigenic effects of previously isolated Bacillus spp. in Japanese quails. A total of 240-day-old Japanese quails were assigned in to six treatments and four replicates. Dietary treatments included the following: negative control (basal diet), positive control (basal diet + 2.5 ppm afltatoxin B₁), probiotic treatments (basal diet + 2.5 ppm afltatoxin B₁), and 10⁸ cfu/ml of different Bacillus spp. (B. megaterium, B. subtilis, or B. laterosporus) in drinking water and treatment P (basal diet + 2.5 ppm afltatoxin B₁ and 2.5 ppm Polysorb®). Body weight gain, feed intake, and feed conversion ratio were not affected by dietary treatments (P > 0.05). Carcass yield significantly increased in B. megaterium and B. subtilis treatments compared with positive control. Supplementation of B. megaterium significantly increased testes, uterus and oviduct weights, skin response to 2,4-dinitro 1-chlorobenzene and phytohemagglutinin, and antibody production against sheep red blood cells (P < 0.05). B. megaterium could significantly increase bursa weight and decrease liver weight compared with positive control (P < 0.05). B. megaterium, B. laterosporus, and Polysorb treatments significantly decreased H:L and aspartate aminotransferase activity in aflatoxin B₁ fed control (P < 0.05). B. megaterium and B. laterosporus significantly increased tibia weight, length, radius, index, and ash content compared with positive control (P < 0.05). All dietary additives significantly reduced meat oxidation, total aerobic bacteria, and spore forming bacteria of ileal content compared with positive control (P < 0.05). Ileal lactic acid bacteria significantly increased in B. megaterium treatment (P < 0.05). Totally, B. megaterium might be a promising probiotic with a comparable afltatoxin B₁ removal potential to commercial toxin binder (Polysorb).

Effects of three Bacillus specious on hatchability, growth performance and serum biochemistry in Japanese quails fed diet contaminated with Aflatoxin B1

 In total, 240 one-day–old Japanese quails (Coturnix Coturnix Japonica) allocated at random to 6 treatments with 4 replicates and 10 birds in each. Treatments used were: 1) Negative control (without any additives or AFB1); 2) Positive control (basal diet + 2.5 ppm AFB1; 2); 3) TA008 (positive control + 108 cfu/ml Bacillus. megaterium TA008); 4) TA049 (positive control + 108 cfu mL-1 Bacillus. subtilis TA049); 5) TA010 (positive control+ 108 cfu mL-1 Brevibacillus brevis TA010) and 6) P (positive control + 2.5 g kg-1 Polysorb® in feed). Hatchability and embryonic mortality were significantly influenced by additives and AFB1 (p < 0.05). Birds fed TA008 improved 12 % hatchability and reduced 10 % embryonic mortality in compared to positive control (p < 0.05). Weight gain and feed conversion ratio did not affected by treatments (p > 0.05). Feed intake was significantly improved in birds feeding by TA008 at 0-21 days (p < 0.05). There were significant differences on relative weights of carcass, gizzard and proventriculus among treatments (p < 0.05). Serum total protein, albumin, cholesterol, glucose, HDL, globulin and uric acid were significantly affected by treatments (p < 0.05). These results showed that the inclusion of bacillus megaterium as potential probiotic into contaminated diets could improve the adverse effects of AFB1 in Japanese quails.

Immune modulatory capacity of probiotic lactic acid bacteria and applications in vaccine development

Vaccination is one of the most important prevention tools providing protection against infectious diseases especially in children below the age of five. According to estimates, more than 5 million lives are saved annually by the implementation of six standard vaccines, including diphtheria, hepatitis B, Haemophilus influenza type b, polio, tetanus and yellow fever. Despite these efforts, we are faced with challenges in developing countries where increasing population and increasing disease burden and difficulties in vaccine coverage and delivery cause significant morbidity and mortality. Additionally, the high cost of these vaccines is also one of the causes for inappropriate and inadequate vaccinations in these regions. Thus, developing cost-effective vaccine strategies that could provide a stronger immune response with reduced vaccination schedules and maximum coverage is of critical importance. In last decade, different approaches have been investigated; among which live bacterial vaccines have been the focus of attention. In this regard, probiotic lactic acid bacteria have been extensively studied as safe and effective vaccine candidates. These microorganisms represent the largest group of probiotic bacteria in the intestine and are generally recognised as safe (GRAS) bacteria. They have also attracted attention due to their immunomodulatory actions and their effective role as novel vaccine adjuvants. A significant property of these bacteria is their ability to mimic natural infections, while intrinsically possessing mucosal adjuvant properties. Additionally, as live bacterial vaccines are administered orally or nasally, they have higher acceptance and better safety, but also avoid the risk of contamination due to needles and syringes. In this review, we emphasise the role of probiotic Lactobacillus strains as putative oral vaccine carriers and novel vaccine adjuvants.

Detection and characterization of purified antigenic proteins from culture filtrate of Mycobacterium bovis strain AN5

Background and Objectives: Bovine tuberculosis diagnosis is usually performed by various tests with specific limitations. Mycobacterium bovis culture filtrate contains antigenic proteins that could be used to improve the sensitivity of bovine tuber- culosis diagnosis. The objective of this study was to identify and purify antigenic proteins from culture filtrates of M. bovis strain AN5 for use in immunological assays. Materials and Methods: Secreted proteins were purified from the heat-treated culture filtrate of M. bovis strain AN5. Pro- teins were precipitated with ammonium sulfate, fractionated by Sephadex G50 chromatography. The protein concentrations and the approximate molecular weight were determined by lowry method and 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Immunological methods, including dot-blotting and western blotting, as- sessed the quality of the isolated proteins. Results: The quantity of antigenic proteins in the culture medium was measured at far more than 15% of the amount of pro- teins secreted into medium. Three main chromatographic fractions obtained and showed concentrations of proteins ranging from 14 to 60 μg/μl with molecular weights in the 10 to 180 kDa range. The purified antigens showed positive reactions to the infected cattle serum throughout dot-blotting. Western blotting revealed a total of 15 to 70 kDa molecular weight proteins. Conclusion: Immunoblotting analysis made it possible to detect and recognize novel antigens that are useful for bovine tu- berculosis diagnosis improvement. This is significant since non-specific reactions were not observed when we utilized serum of cattle experimentally infected with M. bovis as a polyclonal antibody.

Detection and characterization of purified antigenic proteins from culture filtrate of Mycobacterium bovis strain AN5

BACKGROUND AND OBJECTIVES

Bovine tuberculosis diagnosis is usually performed by various tests with specific limitations. Mycobacterium bovis culture filtrate contains antigenic proteins that could be used to improve the sensitivity of bovine tuberculosis diagnosis. The objective of this study was to identify and purify antigenic proteins from culture filtrates of M. bovis strain AN5 for use in immunological assays.

MATERIALS AND METHODS

Secreted proteins were purified from the heat-treated culture filtrate of M. bovis strain AN5. Proteins were precipitated with ammonium sulfate, fractionated by Sephadex G50 chromatography. The protein concentrations and the approximate molecular weight were determined by lowry method and 12% sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Immunological methods, including dot-blotting and western blotting, assessed the quality of the isolated proteins.

RESULTS

The quantity of antigenic proteins in the culture medium was measured at far more than 15% of the amount of proteins secreted into medium. Three main chromatographic fractions obtained and showed concentrations of proteins ranging from 14 to 60 μg/ μl with molecular weights in the 10 to 180 kDa range. The purified antigens showed positive reactions to the infected cattle serum throughout dot-blotting. Western blotting revealed a total of 15 to 70 kDa molecular weight proteins.

CONCLUSION

Immunoblotting analysis made it possible to detect and recognize novel antigens that are useful for bovine tuberculosis diagnosis improvement. This is significant since non-specific reactions were not observed when we utilized serum of cattle experimentally infected with M. bovis as a polyclonal antibody.

Physico-chemical and cytotoxic analysis of a novel large molecular weight bacteriocin produced by Lactobacillus casei TA0021

BACKGROUND AND OBJECTIVES

Antimicrobial peptides produced by lactic acid bacteria have gained enormous attention owing to their health benefits. This study aimed to isolate, purify and characterize the antibacterial protein produced by autochthonous Lactobacillus casei TA0021 strain.

MATERIALS AND METHODS

The antagonistic activity of L. casei TA0021 against a number of pathogenic bacteria was tested by agar well diffusion assay. The antimicrobial agent in the neutralized supernatant fluids was subjected to the action of proteolytic enzymes, catalase, lipase and lysozyme, and their tolerance to variable pH and temperature was estimated. The proteinaceous antagonistic compound was precipitated by 60% w/v ammonium sulphate, desalted and subjected to cation exchange and gel filtration chromatography. Approximate molecular weight of Lactocin was determined by SDS-PAGE and non-denaturing gel electrophoresis. Hemoglobin release assay and cytotoxicity effect of Lactocin TA0021 was determined. The results were statistically analyzed.

RESULTS

The antagonistic agent active against Salmonella Typhimurium and Shigella flexneri appeared resistant to catalase and lipase treatments, while sensitive to the tested proteolytic enzymes. Lactocin TA0021 resisted acidic pH values of 3.0, while alkaline pH values of >9 completely destroyed the activity. The antibacterial peptide was approximately 68 KDa and heat labile as lost its activity at 100°C after 5 minutes. The bacteriocin was non-toxic to MRC-5 cell lines and non-hemolytic. Purification method lead to increase in antibacterial activity while, subsequent decrease in recovery and yield was observed with increasing purification fold.

CONCLUSION

The purified antimicrobial protein from L. casei TA0021 might be used for application in medicinal and food products.

Persistence and safety assessment of novel probiotic strain Lactobacillus plantarum 1 strain Lp86 and Lp36 in Salmonella typhi infected mice

The species of Lactic acid bacteria are known to confer beneficial effects on the host by inhabiting in their gastrointestinal tract (GIT). They succeed in surviving the harsh conditions of the GIT by exhibiting strong tolerance against gastric acids, digestive enzymes and bile simultaneously antagonizing the pathogens by production of antimicrobials. This study has been conducted to elaborate these probiotic characteristics in vivo for which mice were intragastrically given a probiotic approved dose of 1011cfu/ml for 4 days to assess the persistence of two probiotic candidates Lactobacillus plantarum Lp36 and Lactobacillus plantarum Lp86. The fecal count of the test probiotic candidates were seen to persist well in the GIT for 15 days with a count ranging between 104-108cfu/ mg of feces (p>0.01). The safety assessment of L. plantarum Lp36 in healthy and S. typhi in infected mice showed an increase in cell count from (day zero of inoculation) 106cfu/100mg of feces to108cfu/100mg (p>0.01) which was maintained till day six, suggesting the persistence in the GIT. The sections of the mice intestinal lining under scanning electron microscope revealed the adherence of Lp36 and Lp86 to the intestinal epithelia. The mice did not show any adverse effect on its health. These findings make our strains promising probiotic candidates to be used to promote health benefits after further assessments.

Molecular prevalence of bovine noroviruses and neboviruses in newborn calves in Iran

In this study, bovine enteric caliciviruses (BECs) were detected in 49.4% of a total of 253 stool specimens for diarrheic calves collected from 42 industrial dairy farms from March 2010 to February 2012. Genogroup III norovirus (NoVsGIII) were more prevalent (39.5%) than neboviruses (NBs) (15%), and coinfections were observed in 5.1% of the samples tested. Sequence analysis of the partial polymerase gene from 13 NoVsGIII samples indicated the circulation of both genotype 1 and genotype 2 strains. Among the six NB strains sequenced, five were related to the Bo/Nebraska/80/US strain, while one was related to the Bo/Newbury1/76/UK strain.

In vitro and in vivo safety analysis of Enterococcus faecium 2C isolated from human breast milk

INTRODUCTION

Safety analysis of probiotic bacteria is an obligatory characteristic to be evaluated prior to application in food or pharmacological products. This study was designed to evaluate in vitro and in vivo safety parameters of Enterococcus faecium 2C strain, a probiotic candidate isolated from human breast milk.

MATERIAL AND METHODS

E.faecium 2C was studied for its hemolytic activity and phenotypic antibiotics resistance profile. In vivo safety of the mentioned Enterococcus strain was studied by determining acute oral toxicity in Wistar Male rats. The animals were randomly divided into two groups of 3 animals each. The test group animals were gavaged daily with bacterial dose of 1 × 10¹¹ CFU/kg of animal body weight for 21 consecutive days. The animals in control group received normal basal diet without any supplementations. Hematological and biochemical parameters, organ weight, body weight and common health features of the animals were recorded.

RESULTS

E.faecium 2C appeared non-hemolytic and sensitive to the majority of the tested antibiotics. The Wistar male rats fed orally with the mentioned bacterial suspensions survived the test period, and showed normal growth and development. No adverse effects on the general health condition, behavior, and growth were seen in the treated animals compared to control group. Additionally, no significant changes in the hematological results, blood biochemistry, organ weights and histopathology of the rats in treatment groups were observed. None of the vital organs of the treated animals showed signs of bacteremia or infectivity.

CONCLUSION

E.faecium 2C strain isolated from human breast milk might be considered safe for use in probiotic formulations intended for man and animals.

Bacteriocinogenic potential and virulence traits of Enterococcus faecium and E. faecalis isolated from human milk

BACKGROUND AND OBJECTIVES

Human milk is a continuous supply of Lactic Acid bacteria (LAB), including enterococci with probiotic potentials. The aim of this study was to analyze two Enterococcus species, isolated from human milk for their probiotic potential, bacteriocin producing ability and virulence traits.

MATERIALS AND METHODS

Enterococcus faecium TA0033 and E. faecalis TA102 were tested for acid and bile tolerance, survival in simulated gastric and intestinal conditions. The antibacterial spectrum of the isolates was tested by agar well diffusion assay. The antagonistic agent was characterized by physico-chemical methods. The enterocin structural genes, virulence determinants, vancomycin resistance and biogenic amine genes, such as hdc1, hdc2, tdc, ldc and odc were also determined.

RESULTS

The tested isolates survived acidic conditions, high bile salt (1%), simulated gastric and intestinal conditions. The culture supernatant fluids of the two isolates inhibited the growth of Escherichia coli, Listeria monocytogenes, Salmonella typhi, Staphylococcus aureus, Shigella dysenteriae and Streptococcus agalactiae. The antagonistic activity was lost in the presence of proteolytic enzymes but tolerated the action of catalase, lysozyme and lipase. In contrast to enterocin TA102, enterocin TA0033 possessed bactericidal mode of action. Bacteriocin structural genes, entA and entB were present in the genome of the two isolates, while E. faecalis TA102 additionally harboured entP and bac31 genes. The phenotypic and genotypic virulence assessment studies indicated hyaluronidase (hyl) production and vancomycin resistance in E. faecalis TA102 while, none of the isolates harboured the biogenic amine genes.

CONCLUSION

The presence of virulence genes in E. faecalis TA102 calls for careful monitoring of Enterococcus isolates for their safety parameters.

Characterization of Candidate probionts isolated from human breast milk

This study was designed to isolate and identify the potential probionts present in 32 healthy mothers' breast milk. Microbial culture media and 16SrRNA sequencing were used to isolate and identify the bacteria and all isolates were analyzed for their antagonistic potential, resistance to acidic pH, bile salts and survival under simulated gastric and intestinal conditions. The colonization potential was further assessed based on adherence to human enterocyte-like Caco-2 cell lines. The breast milk samples harbored significant numbers of Gram positive and catalase negative (85%) bacteria. Based on 16SrRNA sequencing, these isolates were identified as Lactobacillus casei, L.gasseri, L.fermentum, L.plantarum, Pediococcus acidilactici, and Enterococcus facieum. Among the isolates, P. acidilactici was the most frequent species (71%) present in these samples. Few Gram and catalase positive isolates, Staphylococcus aureus and S.hominiis were also observed. The isolates were viable and unviable in pH 3 and 1.5, respectively, while all isolates survived in 1.0% bile salt. As putative probionts, P.acidilactici 1C showed a significantly higher percentage of adhesion to Caco-2 cells (p&lt; 0.05)than the other two isolates L.plantarum 7A and E.facieum 2C. Bacterial strains isolated from human breast milk were shown to have probiotic properties including anti-infective protection and may be considered as future therapeutics for infants.

Strain differentiation of 13 indigenous Mycobacterium bovis isolates from infected cattle by restriction fragment length polymorphism analysis

Mycobacterium bovis is mainly detected in cattle throughout the world. This bacterium is considered the main causative agent of tuberculosis in man and animals. M. bovis is also reported to be endemic in badgers and in farmed and feral deer. The disease caused by M. bovis is a slow progressive disease with clinical signs not apparent until late in the disease process. key factors for effective control of tuberculosis includes rapid detection, adequate therapy, and contact tracing to halt further transmission. However, in order to locate the source and route of transmission of M. bovis infection, a thorough epidemiological analysis is routinely carried out, that could lead to the control of disease in the herds and avoid economic losses. Recent developments in DNA technology and molecular biology have led to methods for the rapid detection of mycobacterium DNA. Among a number of described molecular methods, IS6110 fingerprinting is the recommended standard primary genotyping method and the most widely used worldwide. In this study, we used restriction fragment length polymorphism analysis with probes derived from the insertion element IS6110, the polymorphic GC-rich sequence (PGRS), and the direct repeat (DR) sequence which proved to be a useful method for differentiating M. bovis strains. A total of 13M. bovis samples from infected cattle in the West Azerbaijan Province of Iran were included in the study. The samples were submitted to the Tuberculosis Reference Laboratory at the Razi Vaccine and Serum Research Institute, Karaj. All isolates were cultivated on Lowenstein Jensen media with pyruvate (pyruvic acid), and then identified according to The World Organization for Animal Health (OIE) recommendations. The extracted genomic DNA samples of the isolates in the study were subjected to IS6110 primers, digested with restriction enzyme PvuII, and hybridized by oligonucleotide probes PGRS and DR. Polymorphic banding patterns obtained after hybridization discriminated the M. bovis strains and a database of strain types was established. Based on our results, the 13 isolates showed five different DNA patterns with a PGRS probe and similarly five patterns were obtained with the DR probe. PP-1 pattern was found almost among all the isolates while a distinct DNA pattern PP-3 was seen specifically from the West Azerbaijan Province.

Characterization of indigenous lactobacillus strains for probiotic properties

BACKGROUND

Probiotics are defined as adequate amount of live microorganisms able to confer health benefits on the host. Currently, most commercially available probiotic products in the market belong to genera Lactobacillus. Traditional dairy products are usually rich source of Lactobacillus strains with significant health benefits. In order to evaluate the probiotic potential of these bacteria, it is essential to assess their health benefits, efficacy, and safety.

OBJECTIVES

The probiotic efficacy of two Lactobacillus strains namely Lactobacillus pentosus LP05 and L. brevis LB32 was evaluated. They were previously isolated from ewes' milk in a rural area in East Azerbaijan, Iran.

MATERIALS AND METHODS

The selected isolates were tested for certain phenotypic characters and identified to genus and species level by 16S rRNA gene sequencing and species specific primers. Further analysis included acid and bile resistance, antagonistic activity, cholesterol removing ability, survival in simulated gastric and upper intestine contents, aggregation and coaggregation properties. Finally, the adhering ability of the selected Lactobacillus strains to epithelial cells was tested using Caco-2 cell lines.

RESULTS

The selected isolates tolerated bile salt concentrations ranging from 0.5% to 3%, however their coefficient of inhibition were varied. Both isolates hydrolyzed bile and grew at pH values of 3, 4, and 5, while isolate LP05 was not able to hydrolyze arginine. Based on 16s rRNA gene sequencing and species-specific primers, the isolates were identified as L. brevis LB32 and L. pentosus LP05. In contrast to simulated gastric conditions, the growth rate of the isolates in alkaline conditions of upper intestine increased significantly with the passage of time reaching its maximum in 24 hours. These 2 isolates inhibited the growth of Listeria monocytogenes, Salmonella enteritidis, Shigella dysenteriae, Staphylococcus aureus, and Streptococcus pneumonia. Furthermore, L. brevis LB32 was able to reduce approximately 86% of cholesterol compared to L. pentosus LP05, which showed only 69% of reduction. Higher aggregation and coaggregation percentage and adherence to Caco-2 cell line was observed in L. pentosus LP05 compared to L. brevis LB32.

CONCLUSIONS

This research study proved the presence of viable probiotic LAB microflora in the ewe milk with enhanced health benefits. The 2 selected Lactobacillus strains could be exploited in dairy or pharmaceutical industry in future.

Intraperitoneal inoculation of Haemophilus influenzae local isolates in BALB/c mice model in the presence and absence of virulence enhancement agents

PURPOSE

Haemophilus influenzae (Hi), predominantly type b accounts for approximately 4% of cases of community-acquired and nosocomial meningitis, in adults. The objective of this study was to evaluate the pathogenicity of local Hi isolates (type b, f and non-typable) in BALB/c mice in the presence of virulence enhancement agents.

MATERIALS AND METHODS

Three different concentrations of the Hi isolates were inoculated intraperitoneally in BALB/c mice in the presence of 2% hemoglobin and 4% mucin as virulence enhancing agents (VEA). The ability of the isolates to produce bacteremia, the percent survival and lethal dose (LD50) were recorded in different challenge groups.

RESULTS

The 3 Haemophilus influenzae type b (Hib) isolates used in study were able to show virulence in BALB/c mice model only in the presence of VEA and their LD50 decreased significantly when 2% hemoglobin and 4% mucin were used. All survived animals showed bacteremia within 4 h of inoculation which was cleared within 18 h. Significant differences (P<0.01) in the virulence and survival percentage of Hib challenge groups were observed based on their dose of inoculation and VEA. None of the isolates were able to induce infection in the absence of VEA. Non-type b isolates failed to produce disease in the mice models even at the highest inoculated dose (10⁸ cfu) and in the presence of VEA.

CONCLUSIONS

BALB/c mice appeared suitable for evaluating the virulence of Hib strains, and 2% hemoglobin with 4% mucin an appropriate concentration for inducing infection in this animal model.

Status and costs of smoking cessation in countries of the Eastern Mediterranean Region

The aim of this cross-sectional observational study was to address the health care situation in regard to smoking cessation efforts and expenditure, and to provide a basis for future studies and for implementing tobacco control programmes throughout the Eastern Mediterranean Region of the World Health Organization. Information collected included methods and cost of services for tobacco cessation from all 16 participating countries. In 10 countries, cessation programmes were directed by primary physicians. In 13 countries, nicotine gum and in 14 countries nicotine patches were accessible in pharmacies. Bupropion was available at pharmacies (with a written prescription) in 6 countries and varenicline in 7 countries. However, the mean cost of each service was significantly higher than the price of a pack of cigarettes. In countries with support services for tobacco cessation, directors need to provide care at the society level that is considerably less costly and widely accessible.

Comparison of Butyric acid concentrations in ordinary and probiotic yogurt samples in Iran

BACKGROUND AND OBJECTIVES

Butyric acid has many applications in chemical, food and pharmaceutical industries. Applications of butyric acid are as an additive to food, flavorings, varnishes, perfumes, pharmaceuticals and disinfectants. Butyric acid concentrations have positive impact on the quality control of milk, yogurt and other probiotic dairy products. The present investigation was undertaken to determine and compare the concentrations of butyric acid (C4) in the ordinary and probiotic yogurt samples by GC method.

MATERIALS AND METHODS

Probiotic yogurt samples were prepared under laboratory scale conditions using two different commercial starters ABY1 and 211, while ordinary yogurt samples lacked the probiotic starter cultures. All samples were analyzed in duplicate, for C4 concentrations by gas chromatography after day 1, 2, 10 and 20 of production, during storage at 4°C. The results were analyzed using ANOVA and Duncan test.

RESULTS

The level of the mentioned fatty acid in ABY1 yogurt sample was significantly higher (0.2%) than in 211 samples (0.17%). These values were significantly lower in ordinary yogurt samples and only 0.07% was recorded in these samples on first day of storage which decreased gradually during storage. The level of reduction in the yogurt samples tested during different time intervals was not similar in all the examined samples, and some showed enhanced reduction than other samples.

CONCLUSIONS

Compared to ordinary yogurt samples, probiotic yogurt samples used in study showed higher levels of butyric acid with increased shelf life.

Biotyping, capsular typing, and antibiotic resistance pattern of Haemophilus influenzae strains in Iran

The aim of this study was to determine the capsular types of Haemophilus influenzae isolated from clinical specimens by slide agglutination serotyping (SAST) and PCR capsule typing methods. All the isolates were biotyped and their antibiotic resistance patterns also determined. Thirteen isolates of serotype b, 2 of serotype e, 4 of serotype f, and 19 nontypeable (NT) isolates were identified by SAST method in 38 H. influenzae culture-positive samples. Capsule typing by PCR increased the proportion of all invasive cases from 34.2% (by SAST) to 60.5%, and 6 culture-negative samples were identified as invasive H. influenzae (Hib) by this method. The discrepancy rate between SAST and PCR results were 41%. Biotypes I, II, and III were the prevalent biotypes whereas biotypes VI and VII were not found. The majority of capsule type b belonged to biotype II. The isolates were resistant to cotrimoxazole (47.1%) and ampicillin (43.6%). Multidrug resistance was observed in 7 of the isolates.

Assessing the effect of administering probiotics in water or as a feed supplement on broiler performance and immune response

1. Two routes of probiotic administration in broiler farms, in water and in feed, were compared using 360 one-day-old male broiler chickens. Controls received no probiotics or antimicrobials. The water group received a probiotic preparation at a rate of 0.5 g/l, and the feed group received it at an inclusion rate of 1 g/kg. 2. Performance of broilers in terms body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) improved when probiotic was provided via drinking water, compared to the control and feed groups. Probiotic administration reduced plasma cholesterol and triglyceride concentrations. 3. Spleen (28 and 42 d) and bursa (42 d) relative weights were influenced by method of probiotic administration, which also improved T-cell dependent skin thickness response to phytohaemagglutinin (PHA) injection. The effect of challenge by dinitrochlorobenzene (DNCB) depended on the method of probiotic administration. 4. The method of probiotic administration can influence the performance and immune competence of birds, and administration via drinking water appears to be superior to the more conventional in-feed supplementation method.