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1.
Food Microbiol ; 105: 104028, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35473981

ABSTRACT

Coagulase-negative staphylococci (CNS) are one of the most pervasive heterogeneous groups of bacteria which are used as starter/adjunct cultures to enhance the aroma and texture of fermented foods. The organoleptic characteristics of fermented foods rely on disparate metabolic attributes of CNS. Nitrate reductase production from CNS improves sensory characteristics of foods by converting nitrate into nitrite. These bacteria utilize arginine via arginine deiminase pathway in the cytosol, and thus, play effective role in the generation of colour of fermented foods. Coagulase-negative Staphylococcus spp. develop flavour in foods by fermenting carbohydrates, converting amino acids, inducing ß-oxidation of lipids, and secreting esterases. Additionally, the characteristic flavour of foods depends on the proteolytic and lipolytic properties of CNS strains too. Coagulase-negative staphylococci strains have revealed exemplary functional or probiotic traits by showing tolerance to acidic pH and bile, depicting adhesion characteristics, producing exopolysaccharide, and secreting therapeutic bacteriocins. Unfortunately, some CNS strains have shown antibiotics resistance, enterotoxins secretions, biogenic amine productions, haemolytic activities, and biofilm formations, thereby indicated the utilization of CNS on strain-by-strain basis. This review sheds light not only on the metabolic heterogeneity and techno-functional traits but also the safety and pathogenic aspects of fermented foods-associated CNS strains.


Subject(s)
Coagulase , Fermented Foods , Coagulase/metabolism , Fermentation , Food Microbiology , Staphylococcus/metabolism
2.
J Equine Vet Sci ; 97: 103339, 2021 02.
Article in English | MEDLINE | ID: mdl-33478757

ABSTRACT

Antibiotics-based therapy plays a paramount role in equine medicine because of their potential pharmacokinetics and pharmacodynamics properties. Conventional antibiotics show bacteriostatic and bactericidal properties by interfering bacterial cell wall and protein synthesis as well as inhibiting RNA polymerase, DNase 1, and DNA gyrase. Antibiotics are extensively used not only for the treatment of varied bacterial infections but also the prevention of postoperative and secondary infections. Surprisingly, antibiotics such as sulfonamides or trimethoprim/sulfonamide combinations, benzylpenicillin, cefquinome, fluphenazine, enrofloxacin, and sodium ceftriaxone cause detrimental effects on horses' health, namely, diarrhea, colitis, nephrotoxicity, ototoxicity, dysrhythmia, arthropathy, ataxia, anorexia, seizures, peripheral neuropathy, and certain neurologic abnormalities. Therefore, in equine practice, it is essential to optimize and analyze the combinations, formulations, route of administration, and dosages of certain antibiotics before administration. This review overviews the mode of actions and pharmacologic attributes of certain antibiotics, commonly used toward the treatment of disparate horse diseases. Most importantly, special emphasis was given to spotlight the potential adverse effects encountered during the administration of antibiotics as therapeutics in horses.


Subject(s)
Bacterial Infections , Horse Diseases , Animals , Anti-Bacterial Agents/adverse effects , Bacterial Infections/drug therapy , Bacterial Infections/veterinary , Diarrhea/drug therapy , Diarrhea/veterinary , Horse Diseases/drug therapy , Horses , Sulfanilamide
3.
Saudi J Biol Sci ; 27(12): 3235-3248, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33304129

ABSTRACT

Soil is an integral part of ecosystem which is niche for varieties of microflora. The present study was investigated to isolate varied strains of bacteria from soil samples of three different geographical regions of Tamil Nadu (India) and evaluate their hydrolytic enzymes (amylase, cellulase, and inulinase) producing potentialities. Among 72 bacterial cultures isolated from Ambattur Industrial Estate, Neyveli Lignite Corporation, and Arignar Anna Zoological Park regions, 41.66, 38.88, and 36.11% of isolates were observed amylase, cellulase, and inulinase producers, respectively. On the other hand, 20.83% of total bacteria isolated from all three regions exhibited concurrent production of amylase, cellulase, and inulinase. Potent isolates depicting maximum enzyme activities were identified as Bacillus anthracis strain ALA1, Bacillus cereus strain ALA3, Glutamicibacter arilaitensis strain ALA4, and Bacillus thuringiensis strain ALA5 based on molecular characterization tools. Further, the thermodynamics parameters, open reading frames (ORFs) regions, and guanine-cytosine (GC) content were determined by distinct bioinformatics tools using 16S rRNA sequences of strains. Minimum free energy values for strain ALA1, strain ALA3, strain ALA4, and strain ALA5 were calculated as -480.73, -478.76, -496.63, and -479.03 kcal/mol, respectively. Mountain plot and entropy predicted the hierarchical representation of RNA secondary structure. The GC content of sequence for strain ALA1, strain ALA3, strain ALA4, and strain ALA5 was calculated as 53.06, 52.94, 56.78, and 53.06%, respectively. Nine ORFs were obtained for strain ALA1, strain ALA3, and strain ALA5 while 10 ORFs were observed for strain ALA4. Additionally, bootstrap tree demonstrated close resemblance of strains with existing bacteria of similar genus. Findings showed higher variability of bacterial diversity as hydrolytic enzymes producers in the investigated geographical regions.

4.
J Equine Vet Sci ; 91: 103149, 2020 08.
Article in English | MEDLINE | ID: mdl-32684248

ABSTRACT

Hendra virus (HeV) is a zoonotic paramyxovirus which causes acute and deadly infection in horses (Equus caballus). It is a rare and unmanaged emerging viral infection in horses which is harbored by bats of the genus Pteropus (Australian flying foxes or fruit bats). The virus is pleomorphic in shape and its genome contains nonsegmented negative-stranded RNA with 18234 nucleotides in length. The virus is transmitted from flying foxes to horses, horse to horse, and horse to humans. Human-to-human transmission of HeV infection is not reported yet. The infection of HeV in horses is highly variable and shows broad range of signs and lesions including distinct respiratory and neurological disorders. Currently, there are no specific antiviral drugs available for the treatment of HeV infection in horses. Vaccination is considered as prime option to prevent HeV infection in horses. A subunit vaccine, called as "Equivac HeV vaccine" has been approved recently for preventing this viral infection in horses. In addition, a plethora of common preventive strategies could help restrict the inter- and intra-species transmission of HeV. Considering the scanty but severe fatality cases of this mystery virus as well as lack of proper attention by veterinary scientists, this review article spotlights not only on the clinical signs, transmission, epidemiology, biology, pathogenesis, and diagnosis of HeV but also the preventive managements of this uncommon infection in horses by vaccination and other precautious strategies.


Subject(s)
Chiroptera , Hendra Virus , Henipavirus Infections , Horse Diseases , Paramyxovirinae , Animals , Australia , Henipavirus Infections/epidemiology , Henipavirus Infections/veterinary , Horse Diseases/epidemiology , Horses , Paramyxovirinae/genetics
5.
J Equine Vet Sci ; 88: 102949, 2020 May.
Article in English | MEDLINE | ID: mdl-32303297

ABSTRACT

Methane (CH4) emission from nonruminant livestock, particularly equines, is a colossal burden for veterinarians worldwide. In view of this, the present context was investigated to predict the antimethanogenic attributes of Moringa oleifera L. associated phytocomponents by targeting methyl-coenzyme M reductase (MCR) receptor in horses using in silico tools. Initially, the pharmacokinetics and ADME (absorption, distribution, metabolism, and excretion) properties of 26 phytocomponents were analyzed using Lipinski's rule of five and Swiss ADME tool, respectively. Among all the tested phytocomponents, 3,5-bis(1,1-dimethylethyl)-phenol, Kaempferol, Moringyne, Niazimisin, and Tetradecanoic acid showed drug-likeness traits with no violation. The molecular docking analysis of selected phytocomponents against MCR receptor was carried out using Hex 8.0.0 docking software. Results estimated the highest binding energy of Tetradecanoic acid against MCR receptor with maximum docking E-value of -142.98 KJ/mol, followed by Niazimisin (-133.98 KJ/mol), Kaempferol (-110.36 KJ/mol), 3,5-bis(1,1-dimethylethyl)-phenol (-93.72 KJ/mol), and Moringyne (-92.62 KJ/mol). In conclusion, Tetradecanoic acid can be utilized as a pronounced antimethanogenic agent in order to develop efficacious CH4 mitigating drugs by inhibiting the methanogenesis mechanism. Most importantly, this in silico outcomes can certainly reduce the cost of in vivo studies strategy toward the development of antimethanogenic drugs for horses in the future.


Subject(s)
Moringa oleifera , Pharmaceutical Preparations , Animals , Horses , Molecular Docking Simulation , Oxidoreductases
6.
Saudi J Biol Sci ; 27(4): 1107-1116, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32256172

ABSTRACT

The present context was investigated to purify and characterize anti-tubercular as well as anticancer protein from fermented food associated Staphylococcus hominis strain MANF2. Initially, the anti-tubercular potency of strain MANF2 was assessed against Mycobacterium tuberculosis H37Rv using luciferase reporter phase assay which revealed pronounced relative light unit (RLU) reduction of 92.5 ± 1.2%. The anticancer property of strain MANF2 was demonstrated against lung cancer (A549) and colon cancer (HT-29) cell lines using MTT assay which showed reduced viabilities. Anti-tubercular activities of the purified protein were observed to be increased significantly (P < 0.05) ranging from 34.6 ± 0.3 to 71.4 ± 0.4% of RLU reduction. Likewise, the purified protein showed significantly (P < 0.05) reduced viabilities of A549 and HT-29 cancer cells with IC50 values of 46.6 and 48.9 µg/mL, respectively. The nominal mass of the purified protein was found to be 7712.3 Da as obtained from MALDI-TOF MS/MS spectrum. The protein showed the sequence homology with 1-336 amino acids of Glyceraldehyde-3-phosphate dehydrogenase from Staphylococcus sp., thus, categorizing as a new class of Glyceraldehyde-3-phosphate dehydrogenase-like protein. The amino acid sequence of the most abundant peptide (m/z = 1922.12) in the purified protein was obtained as 'KAIGLVIPEIDGKLDGGAQRV' and it was identified as peptide NMANF2. In silico tools predicted significant stereo-chemical, physiochemical, and functional characteristics of peptide NMANF2. In a nutshell, protein purified from strain MANF2 can certainly be used as an ideal therapeutic agent against tuberculosis and cancer (lung and colon).

7.
J Equine Vet Sci ; 87: 102923, 2020 04.
Article in English | MEDLINE | ID: mdl-32172913

ABSTRACT

Equine herpesvirus-1 (EHV-1) is one of the most common and ubiquitous viral pathogens infecting equines, particularly horses worldwide. The EHV-1 is known to induce not only humoral but also cellular immune responses in horses. Respiratory distress, abortion in pregnant mares, neurological disorders, and neonatal foal deaths represent EHV-1 infection. Despite the limited success of inactivated, subunit, live, and DNA vaccines, over the past few decades, vaccination remains the prime preventive option to combat EHV-1 infection in horses. However, current vaccines lack the potentiality to protect the neurological form of infections in horses. There is desperate necessity to search effectual EHV-1 vaccines that may stimulate not only mucosal and systemic cellular immunity but also humoral immunity in the horses. This review highlights the state of knowledge regarding EHV-1 biology, EHV-1 pathogenesis, and disparate vaccines studied in the past to prevent EHV-1 infection. The review also underlines the best management strategies which certainly need to be adopted by veterinarians in order to avoid and prevent EHV-1 infection and outbreak in horses in the future.


Subject(s)
Herpesviridae Infections , Herpesvirus 1, Equid , Herpesvirus Vaccines , Horse Diseases , Abortion, Veterinary , Animals , Antibodies, Viral , Female , Herpesviridae Infections/epidemiology , Herpesviridae Infections/veterinary , Horse Diseases/epidemiology , Horses , Pregnancy , Vaccination/veterinary , Virulence
8.
Prep Biochem Biotechnol ; 49(2): 176-183, 2019.
Article in English | MEDLINE | ID: mdl-30688152

ABSTRACT

The present investigation was aimed to determine the anti-pathogenic, antibiofilm, and technological properties of fermented food associated Staphylococcus succinus strain AAS2. The anti-pathogenic attribute of cell-free neutralized supernatant (CFNS) of strain AAS2 was assessed against food-borne and enteric pathogens that revealed promising activity against Staphylococcus aureus and Enterobacter aerogenes with high arbitrary unit of 220.25 ± 3.3 and 170.2 ± 4.6 AU/mL, respectively. Furthermore, the antibiofilm and time-kill assay of CFNS of strain AAS2 depicted remarkable reduction in biofilm formation of indicator pathogens in a dose-dependent manner. Moreover, time-kill assay data revealed the drastic reduction in the viability (log cfu/mL) of S. aureus and E. aerogenes in the presence of varied minimum inhibitory concentration ranges of CFNS. The distinct technological properties of strain AAS2 were demonstrated using standard methodologies. Reported results estimated moderate level of exopolysaccharide (41.3 ± 0.6 mg/L) and lipase production (8.3 ± 0.3 mm), followed by remarkable autolytic (30.1 ± 1.2-43.1 ± 1.3%), catalase (13.82 ± 0.3 AU), and nitrate reductase (10.25 ± 0.3 mM nitrite/mg dry weight) activities under standard conditions. Most importantly, the strain cleared the specific in vitro safety assessment tests. The described anti-pathogenic and technological traits of strain AAS2 paved the way to utilize it in pharmaceutical as well as food processing industries as starter/adjunct culture.


Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Enterobacter aerogenes/drug effects , Fermented Foods/microbiology , Staphylococcus aureus/drug effects , Staphylococcus/chemistry , Enterobacter aerogenes/physiology , Enterobacteriaceae Infections/drug therapy , Humans , Microbial Sensitivity Tests , Staphylococcal Infections/drug therapy , Staphylococcus aureus/physiology
9.
Prep Biochem Biotechnol ; 48(9): 853-866, 2018.
Article in English | MEDLINE | ID: mdl-30303451

ABSTRACT

In this context, carboxymethyl cellulase (CMCase) production from Glutamicibacter arilaitensis strain ALA4 was initially optimized by one factor at a time (OFAT) method using goat dung as proficient feedstock. Two-level full factorial design (25 factorial matrix) using first-order polynomial model revealed the significant (p < 0.05) influence of pH, moisture, and peptone on CMCase activity. Central composite design at N = 20 was further taken into account using a second-order polynomial equation, and thereby liberated maximum CMCase activity of 4925.56 ± 31.61 U/g in the goat dung medium of pH 8.0 and 100% moisture containing 1% (w/w) peptone, which was approximately two fold increment with respect to OFAT method. Furthermore, the partially purified CMCase exhibited stability not only at high pH and temperature but also in the presence of varied metal ions, organic solvents, surfactants, and inhibitors with pronounced residual activities. The enzymatic hydrolysis using partially purified CMCase depicted the maximum liberation of fermentable sugars from alkali pretreated lignocellulosic wastes biomass in the order of paddy straw (13.8 ± 0.15 mg/g) > pomegranate peel (9.1 ± 0.18 mg/g) > sweet lime peel (8.37 ± 0.16 mg/g), with saccharification efficiency of 62.1 ± 0.8, 40.95 ± 0.4, and 37.66 ± 0.4%, respectively after 72 hr of treatment.


Subject(s)
Biomass , Cellulase/biosynthesis , Lignin/metabolism , Micrococcaceae/metabolism , Animals , Cell Culture Techniques/methods , Cellulase/chemistry , Feces/microbiology , Fermentation , Glycosylation , Goats , Hydrogen-Ion Concentration , Lignin/chemistry , Micrococcaceae/enzymology , Protein Stability , Temperature
10.
Microb Pathog ; 125: 96-107, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30195644

ABSTRACT

Cancer and infectious diseases are the preeminent causes of human morbidities and mortalities worldwide. At present, chemotherapy, radiotherapy, immunotherapy, and gene therapy are considered as predominant options in order to treat cancer. But these therapies provide inadequate consequences by affecting both the normal and tumor cells. On the other hand, tuberculosis (TB), and HIV (human immunodeficiency virus) infections are significant threats, causing over a million mortalities each year. The extensive applications of antibiotics have caused the microbes to acquire resistance to the existing antibiotics. With the emerging dilemma of drug resistant microbes, it has become imperative to identify novel therapeutic agents from natural sources as emphatic alternative approach. Over the past few decades, venoms derived from several reptiles, amphibians, and arthropods including snakes, scorpions, frogs, spiders, honey bees, wasps, beetles, caterpillars, ants, centipedes, and sponges have been identified as efficient therapeutics. Venoms constitute plethora of bioactive components, particularly peptides, enzymes, and other chemical entities, which exhibit a large array of anticancer and anti-pathogenic activities. This review highlights the panorama of bioactive components of animal venoms divulging the anticancer, anti-tubercular, and anti-HIV activities. In a nutshell, this context discloses the decisive role of animal venoms as alternative natural resources to combat these deadly diseases of 21st century, and propounding the plausible development of new therapeutic drugs in the present era.


Subject(s)
Acquired Immunodeficiency Syndrome/therapy , Biological Products/therapeutic use , Biological Therapy/methods , Neoplasms/therapy , Tuberculosis/therapy , Venoms/therapeutic use , Animals , Biological Products/pharmacology , Humans , Venoms/pharmacology
11.
Microb Pathog ; 120: 8-18, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29665438

ABSTRACT

The prime focus of the present investigation was to optimize statistically the anti-tubercular activity and biomass of fermented food associated Staphylococcus hominis strain MANF2 using Taguchi orthogonal array (OA) and Box-Behnken design (BBD). The anti-tubercular activity of strain MANF2 was determined against Mycobacterium tuberculosis H37Rv using luciferase reporter phase assay. Among varied media examined, the isolate exhibited impressive anti-tubercular activity with paramount relative light unit reduction of >90% in de Man Rogose Sharpe (MRS) broth. Primarily, the anti-tubercular activity and biomass of strain MANF2 were estimated in MRS broth by optimizing eight diversified parameters using one factor at a time (OFAT) method after working out a series of experiments. The most significant contributing factors selected through OFAT tool were optimized using Taguchi approach with a standard OA layout of L18 (22 × 36). Results demonstrated the significant (P ≤ 0.05) influence of pH, temperature, yeast extract, magnesium sulphate, and glycerol on response variables. These controlled variables were further optimized using BBD matrix at N = 46 by second-order polynomial equation. The fermentation medium of pH 6.5 constituting yeast extract (0.5% w/v), magnesium sulphate (0.1% w/v), and glycerol (1.5% v/v), being further incubated at 30 °C showed enhanced anti-tubercular activity (98.7%) and approximately 4 fold increment in the bacterial biomass yield (8.3 mg/mL) with respect to traditional OFAT method. Three-dimensional response plots of the quadratic model showed interdependent interaction between the significant variables. In conclusion, the present study revealed the first report on the optimization of anti-tubercular activity and biomass of S. hominis via Taguchi OA as well as BBD design, and thus, paved a path for its proficient applications in pharmaceutical industries as dynamic mycobactericidal agent in future.


Subject(s)
Biomass , Fermented Foods , Mycobacterium tuberculosis/drug effects , Staphylococcus hominis/growth & development , Staphylococcus hominis/physiology , Antibiosis , Culture Media , Fermentation , Food Microbiology , Hydrogen-Ion Concentration , Models, Statistical , Probiotics/pharmacology , Temperature
12.
Microb Pathog ; 118: 126-132, 2018 May.
Article in English | MEDLINE | ID: mdl-29550502

ABSTRACT

The desideratum aim of the present context was to isolate a promising antagonist probiotic bacterium from fermented food item as biocontrol agent against uropathogens. Among diversified isolates evaluated for antagonistic trait, Staphylococcus succinus strain AAS2 was found to be an auspicious candidate against urinary tract infection (UTI) causing bacterial pathogens, being the most active against Staphylococcus aureus with substantial activity of 352.5 ±â€¯5.4 AU/mL. Further, the in vitro probiotic attributes of strain AAS2 were assessed using systematic methodology. The isolate exhibited tolerance to acidic condition (up to pH 3.0) and simulated gastric juice (at pH 3.0) with fairly high survival logarithmic cell counts of 5.3 ±â€¯0.15 and 5.23 ±â€¯0.02 log cfu/mL, respectively. Additionally, strain AAS2 showed capability to resist 0.5% w/v bile salt too. It also revealed significant values of auto-aggregation (32.5 ±â€¯1.3-56.5 ±â€¯1.4%) and cell surface hydrophobicity (38.35 ±â€¯1.4%) properties. The isolate showed resistivity towards phenol (6.8 ±â€¯0.08 log cfu/mL) and lysozyme (58.6 ±â€¯1.6%). Further, the susceptibility trait of strain AAS2 to conventional antibiotics made this isolate a promising probiotic bacterium. Most importantly, the isolate depicted DPPH (2,2-Diphenyl-1-picrylhydrazyl) and hydroxyl radical scavenging activities in a concentration dependent manner, thereby exhibiting its propitious antioxidative properties. In a nutshell, the outcomes of this investigation divulge the plausible use of S. succinus strain AAS2 as biocontrol agent against uropathogens, and recommended further applications in pharmaceutics due to its pronounced probiotic traits.


Subject(s)
Antibiosis , Probiotics/pharmacology , Staphylococcus/physiology , Urinary Tract Infections/microbiology , Anti-Bacterial Agents/pharmacology , Bile Acids and Salts/pharmacology , Biphenyl Compounds/pharmacology , DNA, Bacterial , Fermented Foods/microbiology , Food Microbiology , Gastric Juice , Humans , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Hydroxyl Radical/pharmacology , India , Microbial Sensitivity Tests , Microbial Viability/drug effects , Muramidase/pharmacology , Phenol/pharmacology , Picrates/pharmacology , Probiotics/isolation & purification , Staphylococcus/drug effects , Staphylococcus/genetics , Staphylococcus/isolation & purification , Staphylococcus aureus/pathogenicity
13.
Arch Oral Biol ; 89: 99-106, 2018 May.
Article in English | MEDLINE | ID: mdl-29499562

ABSTRACT

OBJECTIVE: To investigate the probiotic characteristics, anti-Candida activity, and antibiofilm attributes of Hentak derived Lactobacillus pentosus strain LAP1. DESIGN: The probiotic properties of strain LAP1 were depicted by adapting standard protocols. The anti-Candida and antibiofilm properties of isolate were determined using agar well diffusion assay and ELISA reader test, respectively. The time-kill assay was performed using viable colony count assay. Further, the co-aggregation property of strain LAP1 was determined based on standard methodology. RESULTS: Strain LAP1 exhibited not only tolerance to acidic pH but also showed resistivity (P ≤ 0.05) to simulated gastric juice exposure. Similarly, the strain was able to tolerate bile salt, showed hyperproteolytic activity, and also depicted susceptibility to most of the antibiotics tested. Auto-aggregation phenomenon (37.5-60%), hydrophobicity nature (42.85%), and survival potentiality of strain LAP1 under freeze-dried condition (9.0 ±â€¯0.01 log CFU/ml) made the isolate a promising probiotic candidate. Cell-free neutralized supernatant (CFNS) of strain LAP1 exhibited potent antifungal activities against C. albicans, C. tropicalis, and C. krusei with arbitrary unit of 150 ±â€¯4.34, 200 ±â€¯5.21, and 130 ±â€¯5.13 AU/ml, respectively and depicted remarkable reduction in the biofilm formation of respective Candida sp. in a concentration dependent manner. Moreover, time-kill assay data provided the growth inhibition of all Candida sp. in a time dependent manner. Additionally, strain LAP1 revealed significant co-aggregate percentage with C. albicans, C. tropicalis, and C. krusei. CONCLUSIONS: L. pentosus strain LAP1 exhibited a good probiotic characteristics, potent anti-Candida activity, and significant antibiofilm property that could be undoubtedly recommended for its vast applications not only in food industries but also as biotherapeutic agent against Candida infections in pharmaceutical industries.


Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Candida/drug effects , Lactobacillus pentosus/physiology , Probiotics/pharmacology , Anti-Bacterial Agents/pharmacology , Bile Acids and Salts , Candida/growth & development , Candidiasis/drug therapy , Colony Count, Microbial , Gastric Juice , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Microbial Sensitivity Tests , Microbial Viability , Peptide Hydrolases , Probiotics/therapeutic use
14.
Microb Pathog ; 116: 289-295, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29407238

ABSTRACT

Zika virus (ZIKV) infection is a life-threatening tropical infection, mainly caused by mosquito bite. After a very long period of quietness, ZIKV infections have become a problematic issue again. Previously, the virus was limited to Africa and Asia only but later it emerged in Brazil, South America, and other parts of the world in 2015. In 2016, there are emerging new cases of sexually transmitted ZIKV infection as well. At present, there is no proper treatment and available pronounced vaccines for the treatment of ZIKV infection. The prime focal point of this review is not only to provide imperative epidemiological information on ZIKV infection in brief but also the current situation of vaccines testing on animal model as well as in clinical trial phases. Currently there is no human vaccine for this pestiferous viral infection. Therefore, prevention, proper management, and up-to-date recommendation are crucial to mitigate the possible risk of vector and non-vector transmission of ZIKV.


Subject(s)
Disease Outbreaks , Drug Discovery/trends , Viral Vaccines/immunology , Viral Vaccines/isolation & purification , Zika Virus Infection/epidemiology , Zika Virus Infection/prevention & control , Zika Virus/immunology , Global Health , Humans , Zika Virus/isolation & purification
15.
Microb Pathog ; 114: 80-89, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29174699

ABSTRACT

Tuberculosis (TB) is a devastating threat to human health whose treatment without the emergence of drug resistant Mycobacterium tuberculosis (M. tuberculosis) is the million-dollar question at present. The pathogenesis of M. tuberculosis has been extensively studied which represents unique defence strategies by infecting macrophages. Several anti-tubercular drugs with varied mode of action and administration from diversified sources have been used for the treatment of TB that later contributed to the emergence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB). However, few of potent anti-tubercular drugs are scheduled for clinical trials status in 2017-2018. Peptides of varied origins such as human immune cells and non-immune cells, bacteria, fungi, and venoms have been widely investigated as anti-tubercular agents for the replacement of existing anti-tubercular drugs in future. In the present review, we spotlighted not only on the mechanisms of action and mode of administration of currently available anti-tubercular drugs but also the recent comprehensive report of World Health Organization (WHO) on TB epidemic, diagnosis, prevention, and treatment. The major excerpt of the study also inspects the direct contribution of different computational tools during drug designing strategies against M. tuberculosis in order to grasp the interplay between anti-tubercular peptides and targeted bacterial protein. The potentiality of some of these anti-tubercular peptides as therapeutic agents unlocks a new portal for achieving the goal of end TB strategy.


Subject(s)
Antitubercular Agents/pharmacology , Computational Biology , Drug Design , Mycobacterium tuberculosis/drug effects , Peptides/pharmacology , Diarylquinolines/pharmacology , Extensively Drug-Resistant Tuberculosis , Humans , Models, Molecular , Nitroimidazoles/pharmacology , Oxazoles/pharmacology , Tuberculosis/drug therapy , Tuberculosis, Multidrug-Resistant , World Health Organization
16.
Microb Pathog ; 114: 239-250, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29196175

ABSTRACT

In the last few years, the demand for the tremendous therapeutic applications of indigenous probiotic bacteria from diversified fermented food products has surged. In view of this, the present study was documented to evaluate the anti-tubercular and probiotic properties of coagulase-negative staphylococci (CNS) indigenous to Koozh, a traditional fermented food product of South India. A total of 18 isolates were purified from Koozh, and tested for anti-tubercular activity against Mycobacterium tuberculosis H37Rv using luciferase reporter phage (LRP) assay. Among them, six isolates revealed higher percentage (>90%) of relative light unit (RLU) reduction. These six isolates were further evaluated for their in vitro probiotic attributes using standard protocols. All six staphylococci strains disclosed good probiotic properties. Moreover, Staphylococcus hominis strain MANF2 showed high cell survival percentage (92.2%) at pH 2.0 as well as towards simulated gastric juice (88.51%). Furthermore, strain MANF2 was found to be resistant to bile salt after 24 h of incubation with maximal viability of 5.71 ± 0.02 log cfu/mL, and depicted the deconjugation of bile salt as well. All the isolates exhibited strong auto-aggregation capacity (44.4 ± 1.2-68.1 ± 1.5%), and hydrophobicity against toluene (55.0 ± 1.2-72.0 ± 1.1%). Additionally, strain MANF2 was observed to be highly resistant to phenol (6.27 ± 0.01 log cfu/mL) and lysozyme (81.1 ± 1.6% viability). Most importantly, all six isolates depicted good hypocholesterolemic effect, slight ß-galactosidase activity, and moderate proteolytic property. The strains were sensitive to all the tested conventional antibiotics, except Nalidixic acid. In addition to this, all staphylococci strains demonstrated significant DPPH (2,2-Diphenyl-1-picrylhydrazyl) scavenging, hydrogen peroxide tolerance, and hydroxyl radical scavenging activity in a dose dependent manner, thereby exhibiting the potent antioxidative properties of isolates. The negative results obtained from haemolytic, DNase, and gelatinase tests revealed the non-pathogenicity and safety aspect of these strains. In a nutshell, the present investigation divulges the persuasive anti-tubercular and probiotic properties of staphylococci, particularly strain MANF2, and recommended the further exploitation of Koozh associated CNS in pharmaceutics.


Subject(s)
Antibiosis , Eleusine/microbiology , Fermented Foods/microbiology , Probiotics/pharmacology , Staphylococcus/physiology , Coagulase/genetics , Coagulase/metabolism , Fermentation , Food Microbiology , Hydrogen-Ion Concentration , India , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/physiology , Probiotics/chemistry , Staphylococcus/classification , Staphylococcus/genetics , Staphylococcus/isolation & purification
17.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-664249

ABSTRACT

Objective:To outline the antibacterial,antioxidant,α-glucosidase inhibition and anticancer properties of Michelia nilagirica (M.nilagirica) bark extract.Methods:The antibacterial activity of bark extracts against human pathogens was assessed by disc diffusion assay.Phytochemical screening,total phenols,flavonoids content,antioxidant and α-glucosidase inhibition properties of bark extracts were investigated by standard methods.In vitro anticancer activity of ethyl acetate extract at various concentrations was observed against HepG2 cells using MTT [3-(4,5-dimethyl thiazol-2yl)-2,5-diphenyl tetrazolium bromide] assay.The presence of diverse bioactive constituents in the ethyl acetate extract was identified using FT-IR and GC-MS analysis.Results:Ethyl acetate extract was found to be the promising agent against human pathogens tested.The ethyl acetate extracts showed the presence of various phytochemicals and comprised the substantial content of phenolics and flavonoids.The ethyl acetate extract showed better antioxidant activities and also revealed remarkable reducing power ability and α-glucosidase inhibition property.The dose dependent assay of extract showed remarkable cancer cell death with IC50 value of (303.26 ± 2.30) μg/mL.FTIRand GC-MS results indicated the presence of major bioactive constituents in the ethyl acetate extract of M.nilagirica bark.Conclusions:Revealing the first report on in vitro biological properties and chemical composition analysis ofM.nilagirica bark extract,our study implied that this plant could be of great importance in food and pharmaceutical industries.

18.
Asian Pac J Trop Med ; 9(11): 1023-1034, 2016 11.
Article in English | MEDLINE | ID: mdl-27890360

ABSTRACT

Tuberculosis (TB) is a symbolic menace to mankind, infecting almost one third of the world's populace and causing over a million mortalities annually. Mycobacterium tuberculosis (Mtb) is the key pathogen of TB that invades and replicates inside the host's macrophage. With the emerging dilemma of multi-drug resistant tuberculosis (MDR-TB) and extensively-drug resistant tuberculosis (XDR-TB), the exigency for developing new TB drugs is an obligation now for worldwide researchers. Among the propitious antimycobacterial agents examined in last few decades, anti-tubercular peptides have been substantiated to be persuasive with multiple advantages such as low immunogenicity, selective affinity to bacterial negatively charged cell envelopes and most importantly divergent mechanisms of action. In this review, we epitomized the current advances in the anti-tubercular peptides, focusing the sources and highlighting the mycobactericidal mechanisms of promising peptides. The review investigates the current anti-tubercular peptides exploited not only from human immune cells, human non-immune cells, bacteria and fungi but also from venoms, cyanobacteria, bacteriophages and several other unplumbed sources. The anti-tubercular peptides of those origins are also known to have unique second non-membrane targets within Mtb. The present context also describes the several cases that manifested the severe side effects of extant anti-TB drugs. The downfall, failure to reach clinical trial phases, inept to MDR- or XDR-TB and severe complications of the currently available anti-tubercular drugs accentuate the imperative necessity to develop efficacious drugs from adequate anti-tubercular peptides. Keeping in view of the emerging trends of drug resistant Mtb globally and unexampled mycobactericidal characteristics of peptides, the anti-tubercular peptides of varied origins can be used as a potential weapon to eradicate TB in future by developing new therapeutic drugs.

19.
Springerplus ; 5(1): 1743, 2016.
Article in English | MEDLINE | ID: mdl-27795886

ABSTRACT

Lactic acid bacteria (LAB) isolated from various foods are important due to their potential to inhibit microorganisms, including drug-resistant bacteria. The objectives of this investigation were to isolate and identify antibacterial substances producing LAB from Hentak, a traditional fermented fish product of Manipur (North-East India), and to optimize the production of antagonistic substances present in cell free neutralized supernatant (CFNS) against enteric bacterial pathogens using the 'one factor at a time' (OFAT) method. Out of 10 LAB, the most potent bacterium producing antibacterial substances was isolated and identified as Lactobacillus pentosus strain LAP1 based upon morphological, biochemical and molecular characterization. MRS (de Man, Ragosa and Sharpe) medium was determined to provide better bactericidal activity (AU/ml) than other tested media against the indicator enteric bacteria, including Staphylococcus epidermidis MTTC 3615, Micrococcus luteus MTCC 106, Shigella flexneri MTCC 1457, Yersinia enterocolitica MTCC 840 and Proteus vulgaris MTCC 1771. The culture conditions (pH: 5, temperature: 30 °C and inoculum volume: 1 %) and medium components (carbon source: lactose and nitrogen source: ammonium chloride) were observed to be the most influential parameters of significant antagonistic activity of CFNS against the enteric pathogens. MRS medium supplemented with Tween20 effectively stimulated the yield of antibacterial substances. The CFNS of strain LAP1 exhibited sensitivity to proteolytic enzyme (pepsin) treatment and heat treatment (60 °C for 60 min, 100 °C for 30 min and 121 °C for 15 min) and lost its inhibitory properties. The CFNS was active at an acidic (pH 3.0) to neutral pH (pH 7.0) but lost its antagonistic properties at an alkaline pH. The CFNS obtained from strain LAP1 scavenges the DPPH (1,1-diphenyl-2 picrylhydrazyl) significantly in a concentration-dependent manner within the range of 8.8 ± 0.12-57.35 ± 0.1 %. The OFAT-based approach revealed the baseline for statistical optimization, the scale-up process and efficient production of CFNS by L. pentosus strain LAP1, which could be used as a potential antibacterial and free radical scavenging agent.

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