African Journal of Microbiology Research

Reports of methicillin-resistant Staphylococcus aureus (MRSA) in food have become more frequent in recent years. The aim of this study was to estimate the presence of MRSA in raw milk, pasteurized milk and ice cream in Tabriz by culture and polymerase chain reaction (PCR) techniques, as well as the determination of their antimicrobial susceptibility. For this purpose, 300 samples of raw milk, pasteurized milk and ice cream were collected from different sellers in Tabriz. They were first evaluated for contamination by coagulase positive S. aureus through culturing method, and then the isolates were subjected to PCR method according to nuc gene in order to confirm S. aureus andmethicillin resistance gene (mecA). Finally the antimicrobial resistance trend of the isolates was investigated by disc diffusion agar method. The cultured samples indicated that 50 (50%) of raw milk samples, 2 (2%) of pasteurized milk samples and 26 (26%) of ice cream samples were contaminated by S.aureus. Forty five, 1 and 23 of these isolates, respectively were confirmed to be S.aureus based on PCR using nuc gene primer. From the total of 69 isolates containing nuc gene, 20 isolates had the resistant mecA gene. Of the 69 isolates, 17 isolates showed simultaneous resistance against 4 antibiotics, 18 against 5 antibiotics, 8 against 6 antibiotics, 8 against 7 antibiotics, 7 against 8 antibiotics, 6 against 9 antibiotics, 2 against 10 antibiotics and 3 isolates against 11 antibiotics. In other words 100% of the isolates showed simultaneous resistance to more than 3 antibiotics. The results provide evidence that the presence of antimicrobial resistant strains of S. aureus has become remarkably widespread in food samples. This calls for better control of the sources of food contamination and as well as the spread of antimicrobial-resistance organisms.

	 

	Key words: Methicillin-resistant Staphylococcus aureus, milk, ice cream, polymerase chain reaction (PCR).

Hamid Mirzaei

Presence and antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus in raw and pasteurized milk and ice cream in Tabriz by culture and PCR techniques

大不里士生乳、巴氏杀菌乳和冰淇淋中耐甲氧西林金黄色葡萄球菌的存在及其抗菌敏感性：基于培养和PCR技术的研究

Bensulfuron-methyl (BSM) is a widely applicable sulfonylurea herbicides. However, BSM remains in environment for extended period of time (over 100 days) and causes a series of environmental problems. In this study, BX2, a strain presents high BSM degradation abilities, was isolated from an activated sludge sample using a continuous enrichment method and determined to be a member of the genus Rhodococcus based on its physiobiochemical characteristics and 16S rRNA gene sequence. Strain BX2 degradated 92% BSM from an initial concentration of 20 mg/L within a 7- day incubation at 35â„ƒ. The specific degradation rate increased with an increase in the initial BSM concentration and the maximum specific degradation rate obtained was 0.146 mg/(mg·d) at 140 mg/L. BSM degradation by strain BX2 can be presented by Haldane’s inhibition equation and the kinetic parameters were: = 16.75 mg/(mg·d), = 7809.36 mg/L and = 2.41 mg/L, respectively. These results indicated that the strain BX2 could be an excellent candidate for bioremediation of BSM-contaminated environments due to its high BSM-degradative ability.

	 

	Key words: Bensulfuron-methyl (BMS), Rhodococcus sp.BX2, isolation, biodegradation.

None Minghua Xiong

Isolation and characterization of Rhodococcus sp.BX2 capable of degrading bensulfuron-methyl

苄嘧磺隆降解菌红球菌BX2的分离与特性研究

Seven bacteria strains that have a comparable or higher cellulose degrading capability than Cellulomonas fimi were screened out and phylogenetically analyzed. Genes encoding 1,4-endoglucosidase (celJV) and glucoside hydrolase family 8 (celG) were cloned from Klebsiella sp. strain IV-3, and then inserted separately or simultaneously into pET-22b(+), pETDuet-1 (pDin) or pDout that combined pETDuet-1 with the pelB leader. pETDuet-1 expressed these cellulose genes as soluble protein, while other vectors mainly as inclusion bodies. The recombinant enzyme(s) from pDin-JV-G and pDin-JV had the highest degrading capability to CMC-Na, with the degrading zone diameter corresponding to 2.6- and 1.9-fold of Klebsiella sp. strain IV-3, respectively. They also showed the highest degrading capability to filter paper, which corresponded well with the highest specific activity. Even though pDin-JV-G had lower expression efficiency, it still had higher degrading capability than pDin-JV, indicating that enzymatic synergism is helpful for cellulose degradation. Key words: Cellulose, cellulase, 1,4-endoglucosidase, glucoside hydrolase family 8, Klebsiella.

Li Qian

Hong Xiao

Chen Xiwen

Chen Defu

Expression and characterization of recombinant cellulases from an isolated Klebsiella

表达与表征自分离的克雷伯氏菌的重组纤维素酶

Three medicinal plants, Aloe vera, Mentha arvensis and Ocimum sanctum were explored for endophytic actinomycetes diversity, plant growth promoting and antimicrobial activity.Endophytic actinomycetes were most commonly recovered from roots (70% of all isolates) followed by stems (17.5%) and leaves (12.5%), respectively.Single genus Streptomyces ranked first (60% of all isolates) followed by Micromonospora (25%), Actinopolyspora (7.5%), and Saccharopolyspora (7.5%).The highest numbers of endophytic actinomycetes were isolated from Ocimum sanctum (45%).Out of 22 isolates tested, 12 showed the ability to solubilize phosphate in the range of 5.4-16.5 mg/100 ml, while 16 isolates produced indole-3 acetic acid (IAA) ranging between 8.3-38.8µg/ml.Nine isolates produced the amount of hydroxamate-type of siderophore ranging between 5.9-64.9µg/ml and only four isolates were able to produce catechol-type of siderophore in the range of 11.2-23.1 µg/ml.Of the nine, interestingly, eight endophytic actinomycetes (88.9%) showed a significant antagonistic activity against one or more phytopathogenic fungi indicating their possible role as plant biocontrol agents.An extended infection of root tissues of Ocimum sanctum by Saccharopolyspora O-9 was observed using transmission electron microscope (TEM).

Gangwar Madhurama

Dogra Sonam

Phutela Gupta Urmil

Nath Kharwar Ravindra

Diversity and biopotential of endophytic actinomycetes from three medicinal plants in India

印度三种药用植物内生放线菌的多样性和生物潜力

High global prevalence of multidrug-resistant bacteria due to antibiotics misuse has prompted the need for novel antibacterial compounds to replace the failing antibiotics. This study investigated some natural habitats in Abuja, Nigeria, for antibiotics-producing bacteria. Thirty-six soil samples from termite mounds, river banks and rhizospheres of Anacardium occidentale L. (cashew tree), Gmelina arborea Roxb. ex Sm. (beechwood), Ageratum conyzoides L. (goat weed) including Cymbopogon citratus (DC) Stapf. (lemon grass) were cultured on nutrient media. Twelve potential antibiotic-producing isolates were identified by crowded plates method and characterized using Bergey&rsquo;s manual. The antimicrobial activities of the filtrates from the isolates against some pathogenic strains namely Streptococcus pneumonia, Salmonella typhi, Escherichia coli (ATCC 25922), Proteus mirabilis, Staphylococcus aureus (ATCC 25923), Candida albicans, Bacillus subtilis and Pseudomonas aeruginosa (ATCC 27853) were determined by agar-well diffusion method. Only 5 eventually inhibited at least 1 test microorganism; 4 showed activities against both Gram-positive and Gram-negative bacteria (broad spectrum) and 2 among the 4 also inhibited Candida albicans, while the remaining 1 inhibited only 1 Gram-positive bacterium (narrow spectrum). The 5 potent antibiotics-producers were Bacillus spp.&nbsp; In conclusion, some natural habitats in the FCT are important sources of antibiotic-producing bacteria.&nbsp; Their antimicrobial lead compounds could be extracted and developed locally for pharmaceutical applications.&nbsp;&nbsp; &nbsp; Key words:&nbsp; Antibiotics-producing bacteria, Bacillus species, natural habitats.

Olumuyiwa Balogun Olasinbo

Chukwudi Ugoh Sylvanus

Olawale Oladosu Peters

Antibiotic-producing bacteria isolated from some natural habitats in the Federal Capital Territory (FCT), Nigeria

尼日利亚联邦首都特区(FCT)某些自然生境中分离的产抗生素细菌

Antwi Apenteng John

Amanor Mfoafo Kwadwo

Odoi Hayford

Orman Emmanuel

Cecil Dodoo Cornelius

Exploring the antimicrobial modulatory potential of the sap from oil palm tree

探索油棕树汁液的抗菌调节潜力

The objective of this study was to describe the resistance profile of enterobacterals isolated from urine samples at the laboratory of Donka National Hospital. Urine samples were collected from both outpatients and hospitalized patients. Cultures were performed using standard techniques, strains were identified using the API 20E kit, and antibiotic susceptibility testing was carried out using the ATB™ UR EU (08) kit. The results were interpreted according to the recommendations of the Antibiogram Committee of the French Society of Microbiology (CASFM v1 2023). Out of a total of 520 urine samples analyzed, 111 were positive for enterobacteral strains. Among them, 75 (67.57%) were of community origin. Escherichia coli was the most represented species (n=61, 55%), followed by Klebsiella pneumoniae (n=24, 22%). The resistance of E. coli strains to third generation cephalosporins (TGC) varied from 5.41% (n=6) to 25.23% (n=28) in the community and from 13 to 38% in the hospital. The profile for carbapenems was categorized as "susceptible to high dosage (SHP)," accounting for 16.22% (n=18). This study provided insight into the resistance profile to antibiotics used in urinary tract infections. The increasing resistance to carbapenems poses a threat to the management of strains producing extended-spectrum beta-lactamases (ESBL). It would be important to strengthen resistance surveillance in this context. Key words: Enterobacteral, urinary tract infection, resistance, community, hospital, Guinea.

KABA Djiba

NIABALY Ousmane

DIALLO Issiaga

Sory Nana SYLLA Ibrahima

G. HOUNMENO Castro

Jean-Jacques Olivier KADIO Kadio

Badara TOURE Aly

SALL Boubacar

BONGONO Emile

KABA Lancei

Ousmane BARRY Alpha

DIABY Maladho

BALAMOU Thomas

KOIVOGUI Pascal

Yaramon KOLIE Ouo-Ouo

Sadjo DIALLO Mariama

CISSE Mohamed

Resistance profile of urine isolate enterobacteral strains at Donka University teaching hospital in Conakry, Guinea

几内亚科纳克里唐卡大学教学医院尿液分离肠杆菌菌株的耐药性特征

The prokaryotic microorganism Mycoplasma gallisepticum (MG) belongs to the phylum Firmicutes, the order Mycoplasmatales, the family Mycoplasmataceae, and the genus Mycoplasma. MG parasitizes the respiratory tract of various poultry species, causing a range of symptoms from indistinct features to tracheitis and air sacculitis. Common signs include respiratory tract infection indicators such as coughing, asthma, a runny nose and rales. Both domestic and international reports underscore MG's transmission and infection capacity, signifying its global importance as a source of poultry infection. Further research is imperative to grasp its impact on both farmed and wild animals. This article comprehensively reviews current research progress on MG, encompassing its biological characteristics, infection traits, pathogenic mechanisms, epidemiology, detection methods, treatment, and control measures. It aims to serve as a reference for comprehensive prevention and control strategies against MG in the future. Key words: Mycoplasma galliscepticum, infection characteristics, epidemiological characteristics, detection methods, treatment, vaccine.

Yang Ruizhi

Lin Xi

Song Huiqi

Zhou Hongmiao

Li Shuang

Li Xuejiao

Hao Bin

Li Lianrui

Mycoplasma galliscepticum: An overview

支原体鸡毒霉形体：概述

Nyamaifofe Dieudonné

Mbugua Amos

Mbogo Kevin

Characterization of novel potential probiotic strains of lactic acid bacteria from rat faeces

大鼠粪便中新型潜在益生菌乳酸菌的特性研究

The use of peanut as a trap-plant for obtaining rhizobia may result in a high diversity of efficient isolates.This study aimed to evaluate the diversity and symbiotic efficiency of peanut rhizobia from the Southeastern region of Brazil.The bacteria were isolated from nodules of two genotypes in soils from the States of São Paulo and Rio de Janeiro, Brazil.The bacteria were authenticated and evaluated regarding to their symbiotic capacity.The rhizobial diversity was evaluated through their culture characteristics on yeast mannitol agar (YMA) culture media and by polymerase chain reaction Box-(PCR).Two selected isolates were characterized phenotypically regarding their capacity to solubilize phosphate, to grow on media with different concentrations of NaCI, pH's and incubation temperatures.For these the 16S rRNA gene sequencing and symbiotic efficiency using non-autoclaved soils were conducted.The majority of the obtained isolates showed rapid growth and acidified the culture medium.Analysis of the isolates through the Box-PCR revealed low similarity to the reference strain indicated for the culture and a large genetic variability of the obtained isolates.The isolates AM 01 and AM 07, which clustered with Bradyrhizobium and Rhizobium genus, respectively, showed a potential for evaluations and a means to recommend new rhizobia strains for peanut.

Publication Information	Publisher: Academic Journals，Publishing cycle: Monthly，Journal Type: journal，Open Access Journals: No
Basic data	Year of publication: 2010，Proportion of original research papers: 0.00%，Self Citation Rate:N.A.， Gold OA Rate: 0.00%
Average review cycle	网友分享经验：平均2.2个月
Average recruitment ratio	网友分享经验：约74%

African Journal of Microbiology Research

Journal Citation Format

A journal article with 1 author

A journal article with 2 authors

A journal article with 3 authors

A journal article with 5 or more authors

Books Citation Format

Thesis Citation Format

Web sites Citation Format

Patent Citation Format

Staying up late manually editing references? ivySCI automatically matches journals and helps you generate references with a single click.

Share Submission Experience

Presence and antimicrobial susceptibility of methicillin-resistant Staphylococcus aureus in raw and pasteurized milk and ice cream in Tabriz by culture and PCR techniques

Isolation and characterization of Rhodococcus sp.BX2 capable of degrading bensulfuron-methyl

Expression and characterization of recombinant cellulases from an isolated Klebsiella

Diversity and biopotential of endophytic actinomycetes from three medicinal plants in India

Antibiotic-producing bacteria isolated from some natural habitats in the Federal Capital Territory (FCT), Nigeria

Exploring the antimicrobial modulatory potential of the sap from oil palm tree

Resistance profile of urine isolate enterobacteral strains at Donka University teaching hospital in Conakry, Guinea

Mycoplasma galliscepticum: An overview

Characterization of novel potential probiotic strains of lactic acid bacteria from rat faeces

African Journal of Microbiology Research