Enhanced production of poly glutamic acid by Bacillus sp. SW1-2 using statistical experimental design

Bacillus sp. SW1-2 producing poly glutamic acid (PGA), locally isolated from Eastern province in Saudi Arabia, was characterized and identified based on 16S rRNA gene sequencing. Phylogenetic analysis revealed its closeness to Bacillus megaterium. The homopolymer consists mainly of glutamic as indicated in the analysis of amino acid. Preliminary optimization of PGA production, through a series of one-variable-at-a-time (OVAT) experiments, revealed maximum PGA production of 10.5 (g/L). Statistically based experiments were applied to optimize culture conditions for production of PGA. Effect of 15 variables were examined for their significance on PGA production using Plackett-Burman factorial design. Among those variables; Na-citrate, (NH4)2SO4, glutamic acid and CaCl2.2H2O were most significant variables that encouraged PGA production, while those negatively affected were; glycerol, glucose and phosphate buffer. Significant parameters were further investigated using Box-Behnken design to define the optimal medium composition. Based on statistical analysis, maximal PGA production on optimized medium was 36.5 (g/L) which was more than 4-folds the basal production medium. Verification experiment was carried out to examine model validation and revealed more than 95% validity.Keywords: Poly glutamic acid, Bacillus megaterium, statistical experimental design, optimization, one-variable-at-a-time (OVAT)African Journal of Biotechnology Vol. 12(5), pp. 481-49

Antimicrobial, Antiviral, and In-Vitro Cytotoxicity and Mosquitocidal Activities of <i>Portulaca oleracea</i>-Based Green Synthesis of Selenium Nanoparticles

The aqueous extract of Portulaca oleracea was used as a biocatalyst for the reduction of Na2SeO3 to form Se-NPs that appeared red in color and showed maximum surface plasmon resonance at a wavelength of 266 nm, indicating the successful Phyto-fabrication of Se-NPs. A FT-IR chart clarified the role of plant metabolites such as proteins, carbohydrates, and amino acids in capping and stabilizing Se-NPs. TEM, SAED, and XRD analyses indicated the formation of spherical, well-arranged, and crystalline Se-NPs with sizes in the range of 2–22 nm. SEM-EDX mapping showed the maximum peaks of Se at 1.4, 11.3, and 12.4 KeV, with weight and atomic percentages of 36.49 and 30.39%, respectively. A zeta potential of −43.8 mV also indicated the high stability of the synthesized Se-NPs. The Phyto-synthesized Se-NPs showed varied biological activities in a dose-dependent manner, including promising activity against pathogenic bacteria and Candida species with varied MIC values in the range of 12.5−50 µg·mL−1. Moreover, the Se-NPs showed antiviral activity toward HAV and Cox-B4, with percentages of 70.26 and 62.58%, respectively. Interestingly, Se-NPs showed a target orientation to cancer cell lines (HepG2) with low IC50 concentration at 70.79 ± 2.2 µg·mL−1 compared to normal cell lines (WI−38) with IC50 at165.5 ± 5.4 µg·mL−1. Moreover, the as-formed Se-NPs showed high activity against various instar larvae I, II, III, and IV of Culex pipiens, with the highest mortality percentages of 89 ± 3.1, 73 ± 1.2, 68 ± 1.4, and 59 ± 1.0%, respectively, at 50 mg L−1. Thus, P. oleracea-based Se-NPs would be strong potential antimicrobial, anti-viral, anti-cancer, and anti-insect agents in the pharmaceutical and biomedical industries

Utilization of Prickly Pear Peels Flour as a Natural Source of Minerals, Dietary Fiber and Antioxidants: Effect on Cakes Production

Prickly pear peel makes up around half of the fruit and is typically thrown away, creating an environmental issue. Due to its high bioactive chemical content, prickly pear peel can easily be used as a functional and nutraceutical ingredient in several food recipes, such as baked products. This study’s objective was to determine whether prickly pear peel flour (PPPF) could successfully be combined (5, 10, and 15%) with wheat flour to make cakes, by analyzing the physical and chemical characteristics of the cakes and performing a descriptive sensory analysis. Prickly pear peel flour contains high amounts of fiber, ash, carbohydrate, phenolic, flavonoid compounds, or antioxidant activity. In addition, PPPF contains high amounts of magnesium, calcium, sodium and potassium. The ethanolic extract of prickly pear peel revealed the presence of 11 phenolic compounds using UPLC-MS/MS. The main constituents in the peel extract were isorhamnetin (27.1%), eucomic acid (19.6%), kaempferol (14.07%), 3-O-Methylquercetin (13.7%), Feruloyl-D-glucose (10.01%) and piscidic acid (8.89%). Results showed that adding PPPF significantly enhanced the amount of fibers, total polyphenols, flavonoids and minerals in the cakes prepared by the addition of 5, 10 and 15% PPPF as compared to the control cake. Moreover, the addition of different levels of PPPF increased antioxidant activity (DPPH and ABTS%) and decreased thiobarbituric acid reactive substances (TBARS) in cakes as compared to the control cake. The descriptive sensory analysis ultimately revealed that cakes made with 10% prickly pear flour received a higher score for their smell, taste or color. In conclusion, prickly pear peel has antioxidant potential and contains biochemical compounds that can be utilized in the enhancement of functional foods and also help to reduce the waste accumulation that causes environmental issues

Cetylpyridinium Bromide/Polyvinyl Chloride for Substantially Efficient Capture of Rare Earth Elements from Chloride Solution

A new sorbent cetylpyridinium bromide/polyvinylchloride (CPB/PVC) was prepared and tested to extract rare earth elements (REEs) from their chloride solutions. It was identified by FTIR, TGA, SEM, EDX, and XRD. The impact of various factors such as pH, RE ion initial concentration, contacting time, and dose amount via sorption process was inspected. The optimum pH was 6.0, and the equilibrium contact time was reached at 60 min at 25 &deg;C. The prepared adsorbent (CPB/PVC) uptake capacity was 182.6 mg/g. The adsorption of RE ions onto the CPB/PVC sorbent was found to fit the Langmuir isotherm as well as pseudo-second-order models well. In addition, the thermodynamic parameters of RE ion sorption were found to be exothermic and spontaneous. The desorption of RE ions from the loaded CPB/PVC sorbent was investigated. It was observed that the optimum desorption was achieved at 1.0 M HCl for 60 min contact time at ambient room temperature and a 1:60 solid: liquid phase ratio (S:L). As a result, the prepared CPB/PVC sorbent was recognized as a competitor sorbent for REEs

Application of Potassium Humate and Salicylic Acid to Mitigate Salinity Stress of Common Bean

In the current study, we investigated the effect of potassium humate (Kh) and salicylic acid (SA) in mitigating the salinity stress of common bean plants. Common bean seedlings were treated with 0.2 g/L SA as a foliar application and 0.3 g/L Kh as a soil application individually or in combination. After 7 days of germination, plants were treated with 50 mM NaCl and normal water as a control. Our results indicate that salt treatment reduced the plant growth (fresh and dry shoots and roots), leaf pigments (total chlorophyll and carotenoids), ascorbic acid (AA), glutathione (GSH), and potassium (K) contents. On the contrary, proline content; sodium (Na); hydrogen peroxide (H2O2); superoxide anion (O2•−); and antioxidant enzymes, including catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD), were increased by saline stress. However, applying either individual Kh and SA or their combination stimulated seedling growth under salinity stress by increasing growth parameters, leaf pigment contents, AA, GSH, proline content, K content, and antioxidant enzymes compared with the control. Additionally, Na content, H2O2, and O2•− were reduced by all applications. The application of the Kh (0.3 g/L) + SA (0.2 g/L) combination was more effective than using the individual compounds. In conclusion, applications of Kh + SA can mitigate salt stress and improve the seedling growth of common bean

Application of Potassium Humate and Salicylic Acid to Mitigate Salinity Stress of Common Bean

In the current study, we investigated the effect of potassium humate (Kh) and salicylic acid (SA) in mitigating the salinity stress of common bean plants. Common bean seedlings were treated with 0.2 g/L SA as a foliar application and 0.3 g/L Kh as a soil application individually or in combination. After 7 days of germination, plants were treated with 50 mM NaCl and normal water as a control. Our results indicate that salt treatment reduced the plant growth (fresh and dry shoots and roots), leaf pigments (total chlorophyll and carotenoids), ascorbic acid (AA), glutathione (GSH), and potassium (K) contents. On the contrary, proline content; sodium (Na); hydrogen peroxide (H2O2); superoxide anion (O2&bull;&minus;); and antioxidant enzymes, including catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD), were increased by saline stress. However, applying either individual Kh and SA or their combination stimulated seedling growth under salinity stress by increasing growth parameters, leaf pigment contents, AA, GSH, proline content, K content, and antioxidant enzymes compared with the control. Additionally, Na content, H2O2, and O2&bull;&minus; were reduced by all applications. The application of the Kh (0.3 g/L) + SA (0.2 g/L) combination was more effective than using the individual compounds. In conclusion, applications of Kh + SA can mitigate salt stress and improve the seedling growth of common bean

Efficient Recovery of Rare Earth Elements and Zinc from Spent Ni–Metal Hydride Batteries: Statistical Studies

Considering how important rare earth elements (REEs) are for many different industries, it is important to separate them from other elements. An extractant that binds to REEs inexpensively and selectively even in the presence of interfering ions can be used to develop a useful separation method. This work was designed to recover REEs from spent nickel–metal hydride batteries using ammonium sulfate. The chemical composition of the Ni–MH batteries was examined. The operating leaching conditions of REE extraction from black powder were experimentally optimized. The optimal conditions for the dissolution of approximately 99.98% of REEs and almost all zinc were attained through use of a 300 g/L (NH4)2SO4 concentration after 180 min of leaching time and a 1:3 solid/liquid phase ratio at 120 °C. The kinetic data fit the chemical control model. The separation of total REEs and zinc was conducted under traditional conditions to produce both metal values in marketable forms. The work then shifted to separate cerium as an individual REE through acid baking with HCl, thus leaving pure cerium behind

Screening for PIK3CA mutations among Saudi women with ovarian cancer

The study aimed to screen for PIK3CA gene mutations among Saudi women with Ovarian Cancer. The study included 298 Saudi women with epithelial ovarian cancers (EOC). DNA sequence analysis was employed to screen for the mutations. DNA sequence analysis of a coding region of exon 9 and 20 of PIK3CA gene revealed mutations in 37/298 (12.4%) EOC patients. About 21/37(56.8%) somatic mutations were identified in exons 9, and 16/37(43.2%) in exon 20. All analysed mutations were missense mutations, the frequencies of which varied from 2.7% to 43.2%. PIK3CA mutation was found to be significantly associated with age (p = .023), grade (p = .001) and histological types (p = .032). Only 6.6% of serous carcinomas and 3.8% of endometrioid had PIK3CA mutation. The Mutated PIK3CA gene was significantly involved in the pathogenesis of EOC among Saudi women. PIK3CA gene mutation and overexpression represent important clinical implications for diagnosis, and prognosis, which can be utilised for better EOC management.Impact statement What is already known on this subject? The detailed molecular and genetic phenomenon underlying the progression of these tumours is still unclear. Recently, the pathogenesis of ovarian cancer has been attributed to mutations of PIK3CA. What do the results of this study add? Mutation in the PIK3CA gene leads to altered PI3K/AKT signalling pathways responsible for the progression of the epithelial ovarian cancer. What are the implications of these findings for clinical practice and/or further research? The Mutated PIK3CA gene was significantly involved in the pathogenesis of EOC among Saudi women. PIK3CA gene mutation and overexpression represent important clinical implications for diagnosis, and prognosis, which can be utilised for better EOC management