ISSN 2736-1756
Research Article
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-009, May, 2019. © International Scholars Journals
Full Length Research Paper
Antifungal and biochemical effects of pseudoguaianolide sesquiterpenes isolated from Ambrosia maritima L.
S. A. M. Abdelgaleil1*, M. E. I. Badawy1, T. Suganuma2 and K. Kitahara2
1Department of Pesticide Chemistry and Technology, Faculty of Agriculture, 21545-El-Shatby, Alexandria University, Alexandria, Egypt.
2Department of Biochemistry and Applied Biosciences, Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065, Japan.
Accepted 23 March, 2019
Abstract
Five pseudoguaianolide sesquiterpenes, namely neoambrosin, damsinic acid, damsin, ambrosin and hymenin isolated from the aerial parts of Ambrosia maritima, were tested for their antifungal activity against the most economic plant pathogenic fungi Botrytis cinerea and Fusarium oxysporum which cause grey mold and root rot diseases, respectively. In mycelial radial growth inhibition assay, neoambrosin and damsin were the most potent, while hymenin and damsinic acid were the lowest effective among the tested compounds. F. oxysporum was more sensitive for inhibition than B. cinerea. On the other hand, the sesquiterpenes caused significant reduction in spore germination of both fungi at 50, 100 and 200 mg/L compared with the control. Complete inhibition was observed when the spores treated with damsinic acid and ambrosin at 200 mg/L. In vivo activities of polyphenol oxidase, polygalacturonase and pectin-lyase in both fungi that treated with 0.5 and 1 fold of the EC50 value were also carried out in order to investigate the biochemical influences of the tested compounds. The compounds showed significant inhibitory effects on the enzyme activities compared with the control however; the activity was not consistently related to the in vitro inhibitory effects.
Key words: Sesquiterpenes, Ambrosia maritime, antifungal activity, Botrytis cinerea, Fusarium oxysporum, biochemical effects.
M. E. I. Badawy, S. A. M. Abdelgaleil*, T. Suganuma and K. Kitahara
Research Article
Optimization of a cryoprotective medium and survival of freeze-dried Bifidobacterium infantis 20088
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-012, May, 2019. © International Scholars Journals
Full Length Research Paper
Optimization of a cryoprotective medium and survival of freeze-dried Bifidobacterium infantis 20088
Shamekhi Fatemeh1, Shuhaimi Mustafa1*, Arbakariya Ariff2, and Yazid A. Manap3
1Department of Microbiology, Faculty of Biotechnology and Biomolecular Science, Putra Malaysia University, 43400, Selangor, Malaysia.
2Department of Bioprocess technology, Faculty of Biotechnology and Biomolecular Science, Putra Malaysia University, 43400, Selangor, Malaysia.
3Department of Food Service and management, Faculty of Food Science and Technology Putra Malaysia University, 43400, Selangor, Malaysia.
Accepted 19 March, 2019
Abstract
Supplementations of formulae with synbiotic compounds of human milk have shown to be able to decrease several gut-related diseases in formula fed infants. This study was carried out to develop a synergistic cryoprotective drying medium for infant formulae probiotic application. Response surface methodology (RSM) was employed to optimize the concentrations of skim milk and prebiotics for improvement of the cell survival of Bifidobacterium infantis 20088, during freeze-drying. The optimal composition was found to be 2.8% prebiotics blended with 16.1% skim milk which could protect 47.63% of cells’ viability. No significant difference (p > 0.05) between the predicted and experimental values validated the model adequacy. Then, the protective effects of optimal composition on the survival of freeze-dried cells were evaluated through different conditions of rehydration, storage and simulated gastrointestinal tract (GIT) as compared to cells dried in phosphate buffer (control). After 120 days storage of freeze-dried stationary phase cells at 4°C, there was 2.33 log (CFU/ml) improvement in the viability of cells as compared to control. With increasing temperature to 25°C, the protective effect of optimized medium was more apparent. Direct rehydration with water led to 0.65 log (CFU/ml) increment in the mortality rate of freeze-dried cells as compared to rehydration with skim milk solution. Also, the mortality rate of cells after sequential incubation in simulated GIT conditions including gastric conditions (pH 3.0 and 4.0, 90 min) and intestinal conditions (pH 7.5, 5 h) were reduced by 1.81 and 0.35 log (CFU/ml), respectively, as compared to the control.
Key words: Bifidobacterium longum subsp. infantis 20088, freeze-drying medium, response surface methodology, storage, infantile gastrointestinal conditions.
and Yazid A. Manap, Shamekhi Fatemeh, Shuhaimi Mustafa*, Arbakariya Ariff
Research Article
Microbiological analysis and somatic cell counts in raw milk from farms of São Paulo State, Brazil
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (5), pp. 001-004, May, 2019. © International Scholars Journals
Full Length Research Paper
Microbiological analysis and somatic cell counts in raw milk from farms of São Paulo State, Brazil
H. Fagundes1, L. B. Pompeu1, C. H. Corassin1 and C. A. F. de Oliveira1,2*
1Departamento de Engenharia de Alimentos, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo. Pirassununga, SP, Brasil.
2Departamento de Engenharia de Alimentos. Av, Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo. Duque de Caxias Norte, 225 CEP 1335-900, Pirassununga, SP, Brasil.
Accepted 25 March, 2019
Abstract
The objective of the study was to evaluate mesophyle, psychrotroph and somatic cell counts (SCC), and presence of Staphylococcus aureus in raw milk produced in 42 dairy farms of the State of São Paulo. Farms were classified according to milk yield in low (< 400 L/day, n = 17), intermediate (400 - 1,000 L/day, n = 8) and high milk production (> 1,000 L/day, n = 17). Mesophylic bacteria counts were lower (p < 0.05) in high production farms, with no differences (p > 0.05) in psychrotrophic and somatic cell counts between the three categories. S. aureus was more frequent (p < 0.05) in the milk of individual cows in intermediate production farms. Percentage of samples that did not comply with SCC tolerance limits in grade B milk ranged from 29.4 (low production) to 52.9% (high production). Results indicate that the greatest difficulties for dairy farms to comply with milk quality parameters are related to the adoption of hygiene practices during milking and to failures in milk conservation.
Key words: Milk quality, mesophyles, psychrotrophs, somatic cell counts (SCC), Staphylococcus aureus.
L. B. Pompeu, C. H. Corassin and C. A. F. de Oliveira*, H. Fagundes
Research Article
Prevalence of typhoid fever in referral hospitals in Umuahia and Aba, Abia State, Nigeria
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-005, April, 2019. © International Scholars Journals
Full Length Research Paper
Prevalence of typhoid fever in referral hospitals in Umuahia and Aba, Abia State, Nigeria
Elendu C. Onwuchekwa1*, Uzochukwu G. Ekeleme2, Oliver Onu-Osi3, Okonudo, I. Diana4
1,3Department of Microbiology, Faculty of Biological and Physical Sciences, Abia State University, Uturu, P.M.B 2000, Uturu, Abia State, Nigeria
2Department of Microbiology, College of Natural and Applied Sciences, Gregory University, Uturu, P.M.B 1012, Uturu, Abia State, Nigeria
4Department of Microbiology, Edo University Iyamho
Accepted 15 April, 2019
Abstract
The prevalence of typhoid fever in referral hospitals in Umuahia and Aba, Abia State, Nigeria was studied using standard microbiological techniques. A total of 500 subjects within the age range of 1-70 years were enrolled. A total of 229 subjects were infected with a prevalence rate of 45.8%. The males had the highest prevalence rate of 50.9%, while females had a prevalence rate of 41.9%. In Aba, 125 (50.0%) subjects were positive, while 104 (41.6%) were recorded in Umuahia. The age group of 21-30 years had the highest rate of 63.3%. Traders were most affected (62.5%). The stool cultures from males had the highest prevalence of 24.8% in ABSUTH, Aba while females had the lowest of 16.0% in FMC, Umuahia. Hence, health care personnel should not totally depend on widal test alone for the diagnosis of enteric fever but should use other diagnostic methods to differentiate Salmonella infection from other related infections.
Key words: Widal test, stool culture, typhoid fever, Salmonella typhi and prevalence.
Uzochukwu G. Ekeleme, Oliver Onu-Osi and Okonudo I. Diana, Elendu C. Onwuchekwa*
Research Article
Characterization and optimization of agarase from an estuarine Bacillus subtilis
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-009, April, 2019. © International Scholars Journals
Full Length Research Paper
Characterization and optimization of agarase from an estuarine Bacillus subtilis
S. Saraswathi*, V. Vasanthabharathi, V. Kalaiselvi and S. Jayalakshmi
The Centre of Advanced Study (CAS) in Marine Biology, Annamalai University, Parangipettai-608502, Tamil Nadu, India.
Accepted 12 April, 2019
Abstract
A bacterium producing agarase was isolated from the vellar estuary and potential strain was identified as Bacillus subtilis. The ideal parameters was found to be of pH 8, temperature of 40°C and 3% of NaCl concentration for optimal growth and agarase activity. Agar as carbon source and yeast extract as nitrogen source was found to be suitable for optimum growth and agarase activity. The activity of enzyme obtained from the cell free filtrate was 15.2 U/L and the activity of the partially purified enzyme was 5.3 U/L and the purified enzyme activity was found to be 2.3 U/L. The stability of the partially purified enzyme on pH profile was found to be pH 8 and thermostability was found to be up to 40°C. The purified enzyme was determined to be homogeneous on the basis of SDS PAGE and had a molecular weight of 20 KDa.
Key words: Agarase, Bacillus subtilis, optimization, stability, SDS PAGE.
V. Vasanthabharathi, V. Kalaiselvi and S. Jayalakshmi, S. Saraswathi*
Research Article
Screening of Saccharomyces cerevisiae for high tolerance of ethanol concentration and temperature
Advanced Journal of Microbiology Research ISSN 2241-9837 Vol. 13 (4), pp. 001-007, April, 2019. © International Scholars Journals
Full Length Research Paper
Screening of Saccharomyces cerevisiae for high tolerance of ethanol concentration and temperature
Parviz Mehdikhani1*, Mahmoud Rezazadeh Bari2 and Hrachya Hovsepyan3
1Scientific Board of Iranian Sugar Beet Seed Institute, Iran.
2Agricultural Sciences College of Urmia University, Iran.
3Agricultural Research Cent of Yerevan, Armenia iran.
Accepted 19 February, 2019
Abstract
The fermentation process of sugar feedstock materials at industrial scale requires the utilization of microorganisms capable of working at high ethanol concentration and high temperatures. The selection of Saccharomyces cerevisiae strains, able to ferment sugars obtained from different material at temperatures above 35°C with high ethanol yield, has become a necessity. Three yeast strains were irradiated with gamma ray and screened for their ability to grow and ferment molasses in a temperature range of 35-45°C. The yeasts were placed in a liquid medium, and irradiated at different doses (0.1, 1, 2, 3, 4, 5 and 10 KGy/h). Although all the isolated strains had growth (in agar plates) at 35 and 40°C, but just two strains showed growth at 42°C, and there was no growth at 45°C. Two pure yeast strains were isolated (PTCC5269 M3 and Areni M7). The efficiency of temperature and high concentrations of ethanol tolerant strains were more than double of ethanol production compared with using the initial strains of yeast. All resistant strains were tested on liquid medium of molasses, and nutrients with 30% (v/v) ethanol had significant difference (P>0.01) for growth intensity at same condition with initial strains.
Key words: Bioethanol, gamma radiation, Saccharomyces cerevisiae, thermotolerant.
Mahmoud Rezazadeh Bari and Hrachya Hovsepyan, Parviz Mehdikhani*