Biomineralization Induced by Cells of Sporosarcina pasteurii: Mechanisms, Applications and Challenges

Biomineralization has emerged as a novel and eco-friendly technology for artificial mineral formation utilizing the metabolism of organisms. Due to its highly efficient urea degradation ability, Sporosarcina pasteurii (S. pasteurii) is arguably the most widely investigated organism in ureolytic biomineralization studies, with wide potential application in construction and environmental protection. In emerging, large-scale commercial engineering applications, attention was also paid to practical challenges and issues. In this review, we summarize the features of S. pasteurii cells contributing to the biomineralization reaction, aiming to reveal the mechanism of artificial mineral formation catalyzed by bacterial cells. Progress in the application of this technology in construction and environmental protection is discussed separately. Furthermore, the urgent challenges and issues in large-scale application are also discussed, along with potential solutions. We aim to offer new ideas to researchers working on the mechanisms, applications and challenges of biomineralization.

Influence of Thermally Processed Zeolite on Properties of Composite Gypsum Binder

One effective way to improve the water resistance of gypsum binder is to add a hydraulic additive consisting of Portland cement and an active mineral additive regulating the formation of highly basic compounds. Various natural and artificial mineral substances are used as additives. It is known the effectiveness of fine-ground natural zeolites of the "Honguruu" (hongurin) deposit in the process of composite gypsum binders (CGB). There are also separate studies proving the increase in the activity of zeolites during their calcination at temperatures of 300-400 ° C. This paper presents the results of the study of the effect of the calcination temperature of hongurin on the properties of CGB. As a result of the studies, the optimal calcination temperature of hongurin - 180 ° C was determined. At the same time, the activity of hongurin increases, which provides significant growth of mechanical indicators of rock on the basis of CGB: the ultimate strength at compression of samples at the age of 28 days from compositions without plasticizer increased by 90% at addition of plasticizer in the amount of 1% - by 35%, and at 2% - by 57%. But with the use of calcined hongurin there is a slight decrease in the water resistance of the rock: in the optimal composition from 0,96 to 0,87, it is explained by the decrease in the activity of hongurin due to the reduction in the number of active groups, and the resulting new centers have a Lewis character.

Justification of approaches to the prevention of occupational and work-related diseases in workers during production and use of artificial mineral fibers

Improvement of the quality of working environment by creating safe working conditions, identification and classification of risks are the basic principles for the prevention of occupational and work-related diseases in workers during production and use of artificial mineral fibers. The most important stage of prevention is therapeutic and preventive measures, including prevention of occupational skin neoplasms in the production of continuous glass fiber, prevention of dusty lung diseases when using mineral wool, vibration- and noise-induced diseases, organization of therapeutic and preventive nutrition.

Combined Effects of Test Media and Dietary Algae on the Toxicity of CuO and ZnO Nanoparticles to Freshwater Microcrustaceans Daphnia magna and Heterocypris incongruens: Food for Thought

The chemical composition of the test medium as well as the presence of algae (microcrustaceans’ food) affects the bioavailability and thus the toxicity of metal nanoparticles (NP) to freshwater microcrustaceans. This study evaluated the effect of the addition of algae (Rapidocelis subcapitata at 7.5 × 106 cells/mL) on the toxicity of CuO (primary size 22–25 nm) and ZnO NP (10–15 nm) to planktic Daphnia magna and benthic Heterocypris incongruens in artificial (mineral) and natural freshwater (lake water). The toxicity of ionic controls, CuSO4 and ZnSO4, was evaluated in parallel. When algae were added and the toxicity was tested in mineral medium, 48 h EC50 of CuO and ZnO NP to D. magna was ~2 mg metal/L and 6-day LC50 of H. incongruens was 1.1 mg metal/L for CuO and 0.36 mg metal/L for ZnO. The addition of algae to D. magna test medium mitigated the toxicity of CuO and ZnO NP 4–11-fold when the test was conducted in natural water but not in the artificial freshwater. The addition of algae mitigated the toxicity of CuSO4 (but not ZnSO4) to D. magna at least 3-fold, whatever the test medium. In the 6-day H. incongruens tests (all exposures included algae), only up to 2-fold differences in metal NP and salt toxicity between mineral and natural test media were observed. To add environmental relevance to NP hazard assessment for the freshwater ecosystem, toxicity tests could be conducted in natural water and organisms could be fed during the exposure.

VALUABLE SPICE-AROMATIC VEGETABLE – MONARDA CITRIODORA L.

One of valuable spice-aromatic vegetable of Lamiaceae family is lemony monarda (Monarda citriodora L.) cultivated as nonperennial crop in most of regions of Russian Federation. Information regarding its parentage and biological special aspects are described here in this article. Brief review regarding nutritional quality and pharmaceutical importance as well as description of four cultivars of lemony monarda (which are currently included to Russian State register of selection invention and approved for usage, two of these cultivars Mona Lisa and Simka were selected and cultivated by Federal Scientific Vegetable Center are given here in this article. Main directions for up-to-date selection and application and practical usage of lemony monarda were indicated. In the field of creation of up-to-date vegetable cultivars, one of the main directions is selection of such a cultivars with high content of biologically active compounds for improvement of antioxidative activity and applicability for its cultivation at hydroponic plant with frame area to provide fresh green vegetables for people all year round. Simka cultivar meets requirements mentioned above and can be cultivated at various types of hydroponic plants including horizontal (salad lines, seedling tables) and vertical (multilayer hydroponics) types using natural (drag turf) or artificial (mineral wool blocks) substrates. This article also describes the main elements of technology of cultivation of lemony monarda in the open and protected ground to get green products and seed production. The features of the preparation of raw materials with a high content of biologically active compounds for fresh consumption and as a spicy-aromatic dry seasoning for salads, meat dishes, as a natural preservative and aromatic of jam, tea and other drinks are shown.

Artificial mineral films similar to biogenic calcareous shells: oriented calcite nanorods on a self-standing polymer sheet

Micrometre-thick calcareous shells consisting of c-axis-oriented calcite nanorods are produced on an organic sheet as mimetics of foraminiferal tests and isopod cornea cuticles.