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Halophilic archaea are a promising natural source of carotenoids. However, little information is available about the biological impacts of these archaeal metabolites. Here, carotenoids of Natrialba sp. M6, which was isolated from Wadi El-Natrun, were produced, purified and identified by Raman spectroscopy, Gc-mass spectrometry, and fourier transform infrared spectroscopy, Lc-mass spectrometry and nuclear magnetic resonance spectroscopy. the c 50 carotenoid bacterioruberin was found to be the predominant compound. Because cancer and viral hepatitis are serious diseases, the anticancer, anti-HcV and anti-HBV potentials of these extracted carotenoids (pigments) were examined for the first time. In vitro results indicated that the caspase-mediated apoptotic anticancer effect of this pigment and its inhibitory efficacy against matrix metalloprotease 9 were significantly higher than those of 5-fluorouracil. Furthermore, the extracted pigment exhibited significantly stronger activity for eliminating HcV and HBV in infected human blood mononuclear cells than currently used drugs. this antiviral activity may be attributed to its inhibitory potential against HcV RnA and HBV DnA polymerases, which thereby suppresses HcV and HBV replication, as indicated by a high viral clearance % in the treated cells. These novel findings suggest that the C 50 carotenoid of Natrialba sp. M6 can be used as an alternative source of natural metabolites that confer potent anticancer and antiviral activities. Halophilic archaea (haloarchaea) belong to the family Halobacteriaceae. This family includes a group of microorganisms that are able to live in hypersaline environments with high salt concentrations (up to 4 M), such as solar salterns, salt lakes and salt deposits 1. Interestingly, these organisms have received increasing attention due to their ability to produce a plethora of compounds with potential applications in many fields of biotechnology, including salt-tolerant enzymes, biodegradable polyesters, exopolysaccharides, antimicrobial halocins, biosurfactants, and photon-driven retinal protein 2. Most haloarchaeal species (e.g., Natrialba) can produce pigments, including carotenoids. Natrialba is an organism in our research that belongs to the Halobacteriaceae family. However, the genus has recently been reassigned to the novel family Natrialbaceae 3. Natrialba sp. M6 is an extreme haloalkaliphile that grows at pH 10.0 and 20-25% w/v NaCl and utilizes a wide range of carbohydrate and noncarbohydrate substrates. Carotenoids are lipid-soluble pigments that vary in colour between yellow, orange, and red. Carotenoids are classified based on the number of carbons in their backbones into the categories C 30 , C 40 and C 50. Most carotenoids exist as a C 40 structure in different living organisms, including bacteria, archaea, fungi, algae, and plants 4. Meanwhile, haloarchaea can produce C 50 bacterioruberin (BR), a rare carotenoid form that contains four hydroxyl groups 5. These pigments are divided into two major groups: xanthophylls (molecu...

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An optimization strategy, based on statistical experimental design, is employed to enhance the production of thermostableamylase by a thermotolerant B. licheniformis AI20 isolate. Using one variant at time (OVAT) method, starch, yeast extract, and CaCl 2 were observed to in�uence the enzyme production signi�cantly. erea�er, the response surface methodology (RSM) was adopted to acquire the best process conditions among the selected variables, where a three-level Box-Behnken design was employed to create a polynomial quadratic model correlating the relationship between the three variables and -amylase activity. e optimal combination of the major constituents of media for -amylase production was 1.0% starch, 0.75% yeast extract, and 0.02% CaCl 2 . e predicted optimum -amylase activity was 384 U/mL/min, which is two folds more than the basal medium conditions. e produced -amylase was puri�ed through various chromatographic techniques. e estimated enzyme molecular mass was 55 kDa and the -amylase had an optimal temperature and pH of 60-80 ∘ C and 6-7.5, respectively. Values of max and m for the puri�ed enzyme were 454 mU/mg and 0.709 mg/mL. e -amylase enzyme showed great stability against different solvents. Additionally, the enzyme activity was slightly inhibited by detergents, sodium dodecyl sulphate (SDS), or chelating agents such as EDTA and EGTA. On the other hand, great enzyme stability against different divalent metal ions was observed at 0.1 mM concentration, but 10 mM of Cu 2+ or Zn 2+ reduced the enzyme activity by 25 and 55%, respectively.

To meet the present and forecasted market demand, bacterial alkaline phosphatase (ALP) production must be increased through innovative and efficient production strategies. Using sugarcane molasses and biogenic apatite as low-cost and easily available raw materials, this work demonstrates the scalability of ALP production from a newfound Bacillus paralicheniformis strain APSO isolated from a black liquor sample. Mathematical experimental designs including sequential Plackett–Burman followed by rotatable central composite designs were employed to select and optimize the concentrations of the statistically significant media components, which were determined to be molasses, (NH4)2NO3, and KCl. Batch cultivation in a 7-L stirred-tank bioreactor under uncontrolled pH conditions using the optimized medium resulted in a significant increase in both the volumetric and specific productivities of ALP; the alkaline phosphatase throughput 6650.9 U L−1, and µ = 0.0943 h−1; respectively, were obtained after 8 h that, ameliorated more than 20.96, 70.12 and 94 folds compared to basal media, PBD, and RCCD; respectively. However, neither the increased cell growth nor enhanced productivity of ALP was present under the pH-controlled batch cultivation. Overall, this work presents novel strategies for the statistical optimization and scaling up of bacterial ALP production using biogenic apatite.

This study highlighted the exploitation of mathematical models for optimizing the growth conditions that give the highest phosphatase productivity from a newfound Lysinibacillus sp. strain APSO isolated from a slime sample. Mathematical models facilitate data interpretation and provide a strategy to solve fermentation problems. Alkaline phosphatase (ALP) throughput was enhanced by 16.5-fold compared to basal medium based on a sequential optimization strategy that depended on two-level Plackett–Burman design and central composite design. The additional improvement for volumetric productivity and specific production yield was followed in a 7 L bench-top bioreactor to evaluate microbial growth kinetics under controlled and uncontrolled pH conditions. The pH-controlled batch cultivation condition neither supported cell growth nor enhanced ALP productivity. In contrast, the uncontrolled pH batch cultivation condition provided the highest ALP output (7119.4 U L−1) and specific growth rate (µ = 0.188 h−1) at 15 h from incubation time, which was augmented > 20.75-fold compared to the basal medium. To the authors’ knowledge, this study is the second report that deals with how to reduce the production cost of the ALP production process via utilization of agro-industrial waste, such as molasses and food waste (eggshell), as a nutrimental source for the improvement of the newfound Lysinibacillus sp. strain APSO ALP throughput.

A locally isolated thermostable Bacillus strain producing polyglutamic acid (PGA) was characterized and identified based on 16S rRNA sequencing. Phylogenetic analysis revealed its closeness to Bacillus licheniformis. To evaluate the effect of different culture conditions on the production of PGA, Plackett-Burman factorial design was carried out. Fifteen variables were examined for their significance on PGA production. Among those variables, K(2)HPO(4), KH(2)PO(4), (NH(4))(2)SO(4) and casein hydrolysate were found to be the most significant variables that encourage PGA production. A correlation between cellular growth, PGA and the produced traces of polysaccharides was illustrated. An inverse relationship practice between cell dry weights and the produced PGA was demonstrated. On the other hand, a direct proportional relation was shown between polysaccharides on one side and cell dry weight and produced PGA on the other. The pre-optimized medium, based on statistical analysis, showed a production of 33.5 g/l PGA, which is more than three times the basal medium.