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Stenotrophomonas rhizophila a Novel Plant-Associated Bacterium With Distinguished PGPRs Properties
2023
Elhosieny, Asmaa | Zayed, Mona | Selim, Shawky | Abdel Aziz, Norhan
Stenotrophomonas sp. is a plant-associated rhizospheric bacteria. It has the capability to enhance plant productivity. It acts as a mineral dissolution and growth promoter for plants under salt-stress conditions. The selected isolates revealed the general morphological and biochemical characteristics of Stenotrophomonas sp. All the isolates exhibited the highest growth density after 15 hr. at 30˚C, resistance to different levels of salinity, different pH levels, and different temperature degrees. Also, the isolates revealed their capabilities to solubilize phosphorus and potassium and to pro-duce different phytohormones. The isolate X.M9 exhibited the highest growth performance in the form of 1.376,1.326,1.292,1.053 and 1.059 OD in most salts’ concentrations compared to all tested isolates respectively. As well it (X.M9) exhibited the highest resistance to low temperatures 10 and 15oC being 0.917 and 1.354 OD respectively. The isolate X.M9 recorded the highest IAA of 83.73 mg/100ml compared to all the tested isolates. The isolate X.M9 were identified using 16 SRNA sequencing and submitted to the GenBank database under accession number No: OP050187 as Stenotrophomonas rhizophila.
Mostrar más [+] Menos [-]Cellulase productrion two fungal strains isolated from Taif in Saudi Arabia
2011
Nasr, S.A. | Hussein, N.A. | Abuo zaid, A.A. | Al-Salemi, F.A
Among 17 fungal isolates isolated from soil of El-hawia, El-hada, El-kaym and Karwa in Taif governorate in Saudi Arabia, two isolates showed high efficacy in producing cellulases enzymes. They were identified to be Altemaria altemata and Aspergillus wentii. Some factors such as carbon and wheat bran as a raw material, nitrogen, pH and incubation temperature were investigated. Results indicated that glucose and cellulose were the most effective as a carbon source while, urea was the best nitrogen source for cellulases production. Initial pH 5.0 and incubation temperatures at 25 or 35°C achieved high cellulases production.
Mostrar más [+] Menos [-]Isolation and Identification of Nonstarter Lactic Acid Bacteria from Traditional Baramily Cheese
2021
Ahmed Ali | Youssef El-Kenany | Ihab Aumara | Osman Aita
Nonstarter lactic acid bacteria (NSLAB) have an important role in quality and safety of traditional Baramily cheese (Domiati cheese related type). Therefore, the objective of this study was to isolate and identify NSLAB with potential technological features from traditional Baramily cheese. Thirty-three samples of Baramily cheese randomly collected from retails in Cairo metropolitan area. The samples were characterized by physiochemical, textural profile and microbiological analysis. Ninety presumptive NSLAB (30 Lactobacillus spp < /em>. and 35 Enterococcus spp < /em>.) strains were isolated on MRS and Kenner-Faecal (KF) Streptococci media; and were characterized for growth temperature, salt tolerance and milk coagulation. All presumptive NSLAB isolates were tolerant to 6.5 % NaCl. Of them, 40 isolates were tolerant to 10.0 % NaCl including 16 presumptive Lactobacillus spp < /em>., and 24 presumptive Enterococcus spp < /em>. isolates based on the results, 11 representative isolates with potential technological features were selected for genetic identification using 16S rRNA technique, then were confirmed for growth and acidity development in skim milk within 48 h, and were tested for antimicrobial activity against some food spoilage and pathogenic microorganisms. The eleven isolates were identified as Ent. durans (1), Ent. faecalis (5), Lb. paraplantarum (1), Lb. plantarum (3), and Lb. rhamnosus (1). All isolated strains were confirmed active in skim milk, and some exhibited antimicrobial activity against tested food spoilage and pathogenic microorganisms. Both Lb. rhamnosus and Lb. plantarum were confirmed as the isolates with high activity in milk. Ent. durans and Ent. faecalis exhibited antimicrobial activity against Enterobacer aerogenes and E. coli. However, Lb. plantarum exhibited antimicrobial activity against both Enterobacer aerogenes, E. coli and Ps. aeruginosa. Listeria. monocytogenes, S. typhimurium, and Campylobacter. jejuni showed significant resistance to all tested NSLAB isolates. They can be concluded that the identified NSLAB isolated can be used to standardized and improve the quality and safety of Baramily cheese and other types related to Domiati cheese
Mostrar más [+] Menos [-]Cellulase production by local bacteria isolated from taif in Saudi Arabia
2011
Nasr, S.A. | Abozaid, A.A. | Hussein, Y.A. | Al-Salemi, F.A
Among 20 bacterial isolates isolated from the soil of El-hawia, El-hada, El-kaym and Karwa in Taif governorate in Saudi Arabia,two isolates had high efficacy in producing cellulase enzyme. They belonged to genus Bacillus (Bacillus 8 and 17). Some factors such as carbon source and wheat bran as a raw material, nitrogen source, pH and. incubation temperature were investigated. Results indicated that CMC and cellulose were the most effective as they enhanced cellulases production .Sodium nitrate and ammonium chloride were the best nitrogen sources for cellulases production. Initial pH 7.0 was found to be optimal for growth and cellulase production. Incubation temperatures at 25 - 40°C achieved high cellulases production by the two isolates.
Mostrar más [+] Menos [-]Microbial production of thermoalkaliphilic enzymes from El-Khorma governorate for application in biodetergent technology
2011
Bayoumi, R.A. | Atta, H.M. | El-Sehrawey, M.H. | Selim, Sh.M.
Detergents are an undetectable source of pollution, which hidden in most of our daily activities. Detergents could cause harmful effects before they are completely degraded. It is wise to reduce the amount of detergents that usually used by invention new bio-friendly formula contains efficient enzymes such as protease. Screening studies were carried out for one hundred and fifty bacterial isolates with respect to their ability to produce protease(s), after growing on slaughter house wastes (SHW) isolated from EI-Khorma governorate,Taif, Kingdom of Saudi Arabia (KSA) at 55°C, and pH 9. The most potent thermophilic bacterial isolate concerning of alkaline thermostable protease(s) production was identified as Bacillus licheniformis EGT50. Alkaline thermostable proteases productivity by the most potent bacterial isolate was affected by substrate concentrations (solid substrate), carbon source, nitrogen source, amino acid supplements, incubation temperature, incubation period, and inoculum size. Maximum both enzymes production by B. licheniformis EGT50 was obtained on SHW concentrations, 7.5 %; galactose; diammonium hydrogen phosphate; arginine at 55°C for 72 h. when inoculated by 0.5 ml. The protease production under all optimal conditions was increased many folds from 563.68 to 17825 U/ml (31 fold). The purification fold of B. licheniformis EGT50 alkaline thermostable protease increased to 394.7 after applying Sephadex G200 column chromatography techniques. The enzyme productivity of protease has been determined and the result proved the possibility to use the crude and purified enzymes in biodetergent technology.
Mostrar más [+] Menos [-]MORPHOLOGICAL AND MOLECULAR CHARACTERIZATION OF ECTOMYCORRHIZAL FUNGI ISOLATED FROM EGYPTIAN ENVIRONMENT
2007
Mona Zayed | Sh Selim | Wedad Eweeda | M Ali | A Hazem
In a trial to isolate and identify ectomycorrhi-zal fungi for the first time in Egypt 13 sporocarpes associated with rang of plants grown on Egyptian soils were collected, to be used for this purpose. Fungal isolates were obtained from collected spo-rocarpes and tested for ectomycorrhiza formation with Bauhinia sp. and Pinus seedlings. The paper sandwich technique was used for simultaneous inoculation of root apices Bauhinia to produce synchronously developing ectomycorrhizas. Typi-cal ectomycorrhizal roots were obtained within 14 days after inoculation with the collected strains. The isolates tested for ectomycorrhiza formation with Pinus sp. to ensure their identity by for-mation of distinct root characteristics on this host. Root colonization levels varied markedly among the tested fungal strains with respect to growth enhancement and NPK uptake of Pinus shoots and roots.
Mostrar más [+] Menos [-]Stenotrophomonas rhizophila a Novel Plant-Associated Bacterium With Distinguished PGPRs Properties
2023
Asmaa Elhosieny | Mona Zayed | Shawky Selim | Ayman Yassen | Norhan Abdel Aziz
Stenotrophomonas sp. is a plant-associated rhizospheric bacteria. It can enhance plant productivity. It acts as a mineral dissolution and growth promoter for plants under salt-stress conditions. The selected isolates revealed the general morphological and biochemical characteristics of Stenotrophomonas sp. All the isolates exhibited the highest growth density after 15 hr. at 30oC, resistance to different levels of salinity, different pH levels, and different temperature degrees. Also, the isolates revealed their capabilities to solubilize phosphorus and potassium and to produce different phytohormones. The isolate X.M9 exhibited the highest growth performance in the form of 1.376,1.326,1.292,1.053 and 1.059 OD in most salts’ concentrations compared to all tested isolates respectively. In addition, it (X.M9) exhibited the highest resistance to low temperatures 10 and 15oC being 0.917 and 1.354 OD respectively. The isolate X.M9 recorded the highest IAA of 83.73 mg/100ml compared to all the tested isolates. The isolate X.M9 was identified using 16 SRNA sequencing and submitted to the GenBank database un-der accession number No: OP050187 as Stenotrophomonas rhizophila.
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