International Journal of Advanced Biological and Biomedical Research

Biochemical Characteristics and Antibiotics Susceptibility of Streptococcus Mutans Isolates from Dental Caries in Baghdad City

Aya Raad Salh; Mohsen Hashim Risan; Hameed Majeed Jasim

Volume 10, Issue 1 , February 2022, , Pages 32-43

https://doi.org/10.22034/ijabbr.2022.534492.1363

Abstract

Background: Genus Streptococcus comprises important pathogens that have a severe impact on human health. According to the classification in Bergey's Manual of Determinative Bacteriology, ... Read More Background: Genus Streptococcus comprises important pathogens that have a severe impact on human health. According to the classification in Bergey's Manual of Determinative Bacteriology, the genus Streptococcus includes the pyogenic, oral and anaerobic groups of streptococci, as well as a group of other streptococci. S. mutans is a Gram-positive bacterium, which plays a key role in the formation of the dental plaque biofilm as an early coloniser and is the most important bacterium in the formation of dental caries. S. mutans do not have flagella, but do have pili and are non-motile facultative anaerobes that grow optimally at 37 °C. Methods: Eighty samples were collected from patients with different dental caries (pit, fissure and dental roots). The patients had referred to Al-dora Health center and Al-Zewiya Health center in Baghdad city. Bacterial isolates obtained from dental caries samples were streaked on selective medium (Mitis Salivaris Agar) for isolation of S. mutans, then the plates were incubated at 37 °C for 48 hours under anaerobic conditions. Bacterial isolates were identified according to their morphological and cultural characteristics and biochemical tests. The disk diffusion method was used to test the antibiotic susceptibility of the selected isolate to different antibiotics. A sterile cotton swab was dipped in fresh culture of S. mutans and streaked on the surface of Muller-Hinton agar plates by rotating the plate approximately 60 between streaking to ensure even distribution. The inoculated plates were incubated at room temperature for 10 minutes to allow absorption of excess moisture, then antibiotic disks were fixed by sterile forceps on the surface of plates and incubated at 37 °C for 18 hrs.Results: Totally, 98 bacterial isolates were obtained. The results indicated that antibiotic susceptibility pattern of the locally isolated S. mutans S2 was resistant to two antibiotics (bacitracin and erythromycin), while it was sensitive to the other eight antibiotics, consisting amoxicillin, ampicillin, chloramphenicol, vancomycin, clindamycin, imipenem, gentamycin and cephalothin.Conclusion: Locally isolated S. mutans S2 was sensitive to different antibiotics, while it resisted only against bacitracin and erythromycin.

Screening of bacteria Streptomyces Waksman and Henrici 1943 (Streptomycetaceae) Isolates from Soil Samples in Iraq

Bassam Qasim; Mohsen Hashim Risan

Volume 9, Issue 4 , December 2021, , Pages 340-351

https://doi.org/10.22034/ijabbr.2021.534456.1364

Abstract

Background: The genus Streptomyces Waksman & Henrici 1943 includes aerobic, gram-positive, and filamentous bacteria which produce well developed vegetative hyphae with branches. ... Read More Background: The genus Streptomyces Waksman & Henrici 1943 includes aerobic, gram-positive, and filamentous bacteria which produce well developed vegetative hyphae with branches. The wall consists of a large mixture of different compounds, including peptidoglycan, teichuronic acid, teichoic, and polysaccharides. The peptidoglycan components consist of glycan as a chains of irregular N-acetyl- d-muramic acid (NAM), diaminopimelic acid, and N-acetyl-d-glucosamine (NAG) and DAP, which is unique in the cell walls of prokaryotic microorganisms. The teichoic and teichuronic acid are chemically bonded to peptidoglycan.Methods: One gram of soil samples was used to make suspension, by adding 99 mL of sterile distilled water (stock suspension) into it and shaking it in a shaker at 160 rpm for 30 minutes at room temperature. Serial dilutions from 0.1-0.001 were made from the stock suspension, and left for 10 minutes. After shaking, 0.1 mL of each dilution was cultured on Yeast Extract and Malt Extract agar (YEME) with Streptomycin 50 ug/mL. The inoculated plates were incubated at 28 °C for 7 to 10 days. Based on cultural characteristics, suspected colonies of Streptomyces were selected, which are characterized as small, white, pin-point, rough, chalky, and a clear zone of inhibition around them. These colonies were confirmed their identification by types of Gram’s stain, aerial and substrate mycelium color, pigment production, and pigment color. Streptomyces were re-streaked on International Streptomyces project (ISP) to obtain pure colonies used for identification. Results: The current study aimed to screen bacteria Streptomyces isolates. Only 21 samples of soil were suspected to contain Streptomyces, and 45 isolates were obtained with different morphology types per samples of soil. The colonies suspects were selected basis on color that ranged from gray, white and creamy. The microscopic examination of local Streptomyces spp. after Gram-staining method was conducted. The observations revealed that local Streptomyces is gram positive and rod shaped similar to features of fungal in possessing branched mycelium. The Streptomyces produced extra cellular enzymes like amylase, urease, catalase, protease, Gelatinase, cellulase and phosphatase. Utilization of citrate was positive, with no Melanine reaction production and soluble pigmented, and negative for indole production.Conclusion: The identification of the Streptomyces is a very complex process. Morphological and biochemical characteristics are two important aspects for the classification in the Streptomycetaceae family. By studying the morphological, cultural, and biochemical characteristics, it is observed that the local isolates are belonging to the genus of Streptomyces.

Bimolecular identification of M.ovinpeumoniae from nasal swab samples of sheep from various districts of Balochistan, Pakistan

Shahid Amin; Sajjad ur Rahman; Iftikhar Hussain; Ghulam Muhammad; Mohammad Arif Awan; Zafer Ahmad; Mohammad Masood Tariq; Muhammad Irfan Ullah; Muhammad Azam Kakar

Volume 4, Issue 1 , March 2016, , Pages 32-39

https://doi.org/10.26655/ijabbr.2016.2.4

Abstract

Mycoplasma ovipneumoniae is an important respiratory pathogen of sheep across the world. In the present study nasal swab samples (n=778) were processed and 51isolates of M. ovipneumoniae ... Read More

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Keywords = Biochemical

Biochemical Characteristics and Antibiotics Susceptibility of Streptococcus Mutans Isolates from Dental Caries in Baghdad City

Abstract

Screening of bacteria Streptomyces Waksman and Henrici 1943 (Streptomycetaceae) Isolates from Soil Samples in Iraq

Abstract

Bimolecular identification of M.ovinpeumoniae from nasal swab samples of sheep from various districts of Balochistan, Pakistan

Abstract