Hot springs are known to be rich in diverse microorganisms, including thermophilic bacteria capable of producing industrially important enzymes. This study aimed to isolate, purify, and identify thermophilic bacteria from three hot springs located in the southern region of Saudi Arabia, namely Al-Ma'a Al-Har, Al-Aredhah, and Al-Ahsarai hot spring. The isolated bacterial isolates were screened for amylase enzyme production, and the most potent isolate, Cytobacillus firmus OQ834432 isolate OHA8, was selected for large-scale production of the amylase enzyme. The enzyme was then purified using salt precipitation, Sephacryl S-200 chromatography, and DEAE-Sepharose column chromatography. A total of twenty-one bacterial species were identified, with Cytobacillus firmus exhibiting the highest amylase activity. The optimal conditions for the amylase enzyme activity were found to be at 50℃ and pH 5.0, with a 153% enhancement in activity in the presence of magnesium ions. The enzyme's activity was inhibited by EDTA and was found to be active with starch and amylopectin at 100% and 110.3%, respectively. In conclusion, this study demonstrates the potential of thermophilic bacteria from hot springs to produce industrially important enzymes and provides insights into the optimal conditions for enzyme production and activity. These findings have significant implications for the development of biotechnological applications utilizing thermophilic bacteria in various industrial sectors.
Deadly pathogenic multidrug-resistant bacteria (MDR) are becoming more prevalent every day and represent a major danger to human health. This research aimed to isolate and quantify vancomycin resistant MDR (VRMDR) Enterococcus faecalis and extended-spectrum β-lactamase MDR (ESBLMDR) Klebsiella pneumoniae by detecting specific genes and the use of TiO2 Aspergillus oryzae nanoparticles as antibacterial agent against the two strains. One hundred and fifty clinical specimens were collected from Mbarret El-Asafra Hospital, 80 isolates were E. faecalis and 70 isolates were K. pneumoniae. 21/80 was found to be VRMDR E. faecalis, the findings showed that 76.19% of VRMDR E. faecalis strains harboured the VanA gene and 90.47% harboured the VanB gene, while 66.66% of them carried the two resistance genes. On the other hand, 18/70 samples were found to be ESBLMDR K. pneumoniae, the findings showed that 72.22% of ESBLMDR K. pneumoniae strains harboured the blaTEM gene and 61.11% harboured the blaSHV gene, while 33.33% of them carried the two resistance genes. 30µg/ml of nano TiO2 A. oryzae was found to be the minimal inhibitory concentration (MIC) for the VRMDR E. faecalis, while 50µg/ml of nano TiO2 A. oryzae was found to be the MIC for the ESBLMDR K. pneumoniae. The IC50 of TiO2 A. oryzae nanoparticles against human gastric epithelial cell line (GES1) was 563.023±31.7µg/ml compared to chloramphenicol, imipenem drugs and TiO2 nanoparticles showing (563.023±31.7µg/ml, 169.386±9.32µg/ml, 71.692±5.05µg/ml and 30.562±3.22µg/ml) respectively, showing that TiO2 nanoparticles, chloramphenicol and imipenem were more cytotoxic on GES1 normal cells than TiO2 A. oryzae nanoparticles.
The main objective of the current research was to isolate new Streptomyces species that has the ability to degrade chicken feathers through keratinase production. Nineteen Egyptian local Streptomyces strains were isolated from soil and tested for their ability to produce keratinase enzyme from chicken feathers. Maximum keratinolytic activity was achieved with a novel Streptomyces isolate strain no 6. that was identified by 16S rDNA method with a given name of Streptomyces sp. NRC FM (Accession no. LC456058). The optimum culture conditions for the highest keratinase production were found to be a pH 9.5, at a temperature of 37˚C and agitation speed of 180 rpm. Interestingly, chicken feathers were completely degraded after 9 days of incubation with the novel strain. Keratinase was precipitated using acetone and its molecular weight was estimated to be 30 and 42 kDa using SDS-PAGE. The results obtained suggest that the isolated novel Streptomyces sp., NRC FM, can be considered as a useful biotechnology tool for valorization of keratin-containing wastes.
