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Nowadays, climate change and global warming are major environmental issue due to continuous increase to atmospheric carbon dioxide concentration and vast growth in industrialization (Yaashikaa et al. in J CO2 Utiliz 33:131–147, 2019).

In these days, the interest in vitality has quickly expanded a direct result of the monetary development around the world.

Biosequestration of carbon dioxide using microbial carbonic anhydrase (CA) is one of the most environmentally friendly and attractive biomimetic routes for carbon sequestration due to its economic viability and environmental compatibility. However, the optimum use of microbial CA in industrial applications is hindered by the cost and unstable nature of enzyme. The use of engineered microbial CA as a reaction promoter can overcome these obstacles. Engineered microbial CA can be used to accelerate the CO2 hydration rate with improved thermokinetic stability. This chapter introduces multiple possibilities for CA engineering methods to promote the enhancement of carbon dioxide conversion and economical use of microbial CA. To reduce the greenhouse effect of carbon dioxide, further research should be devoted to the large-scale production, long-term performance of engineered CA, and developing highly efficient engineering strategies.

In the present era, global warming is a serious environmental concern, which is mainly caused by higher CO2 concentration in the atmosphere. In order to mitigate the CO2 level, it should be captured and converted. Plant, algae, and microbes present in nature have the capability to fix the atmospheric CO2, but in the industrial areas where CO2 concentration is high, the biological system cannot capture the whole CO2. Nowadays, various nanoporous materials, chemicals, and graphene oxide particles have been used to capture and convert CO2 into value-added products. The conversion of CO2 into chemicals and fuels using chemical, enzymatic, and electrochemical systems may offer a promising strategy to recycle a huge quantity of carbon. In this review, we discuss the recent advances in various methods used for CO2 capture and its conversion. However, various methods have been reported for CO2 capture and its conversion, but individually each of these methods has its own limitations, which makes their commercial usage more complex.

Inert municipal solid waste consists of waste which is chemically and biologically uncreative. It covers 30%–50% of total municipal waste and challenge for its management. Such waste is a burden for its management in landfill sites due to quantity. It affects human health and environment due to the presence of other types of secondary pollutants trapped or immobilized on it. The major inert municipal waste includes concrete and demolition, debris, glass, etc. Its management includes conversion toward recycled concrete aggregate, building material, tiles etc. Some research studies propose the conversion of these into adsorbent materials as a new and value-added approach.

Radon (Rn-222), thoron (Rn-220) and its progeny are the natural radioactive gases emitted everywhere in different concentration. These carcinogenic substances were known to be responsible for lung cancer. Human exposure of these gases in an indoor environment was principally dependent on the house types like concrete, slate, mud-tin etc. Rate of exposure is also influenced by unplanned construction and associated poor ventilation.The study of inhalation dose with house type and the associated indoor environment were important to study the exposure due to natural ionising radiation. In this study, we report the results from passive measurement of indoor radon, thoron and their progeny concentrations in Bilaspur district of Himachal Pradesh, India. The measurement was performed at selected 95 dwellings, based on outdoor ambient gamma level and type of houses. Highest inhalation dose due to indoor radon, thoron and their progeny were found in mud houses in comparison to other concrete, slate and tin type of houses. The average annual inhalation dose thus found due to exposure to radon and thoron varies from 0.1 to 0.5 mSv/y in the concrete, 0.3–0.6 in mud and slate type of houses whereas 0.1–0.4 in mud-tin type. The estimated average value of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose.

Carbonic anhydrase modification (chemical and biological) is an attractive strategy for its diverse application to accelerate the absorption of CO2 from a flue gas with improved activity and stability. This article reports various possibilities of CA modification using metal–ligand homologous chemistry, cross-linking agents, and residue- and group-specific and genetic modifications, and assesses their role in carbon management. Chemically modified carbonic anhydrase is able to improve the absorption of carbon dioxide from a gas stream into mediation compounds with enhanced sequestration and mineral formation. Genetically modified CA polypeptide can also increase carbon dioxide conversion. Chemical modification of CA can be categorized in terms of (i) residue-specific modification (involves protein–ligand interaction in terms of substitution/addition) and group-specific modifications (based on the functional groups of the target CA). For every sustainable change, there should be no/limited toxic or immunological response. In this review, several CA modification pathways and biocompatibility rules are proposed as a theoretical support for emerging research in this area.

Microbial diversity was investigated in the soil samples from Himachal Pradesh and Kumaun Himalaya. Phylogenetic analysis of all bacterial strains confirms the presence of Proteobacteria (55%), Firmicutes (27%), Actinobacteria (18%) and Bacteroidetes (6%) like mesophilic microbial communities in the study area. Shannon Index was used as a tool for bacterial diversity assessment. Isolated bacterial strains were further screened for extracellular crude carbonic anhydrase (CA) production. Pseudomonas spp. is able to produce extracellular CA, while other bacterial strains showed intracellular activity. 16s rRNA sequencing and FT-IR was used to identify the isolates and CA application in CO2 mineralization.

The aim of this work was to study the CO2 bio-sequestration application of indigenous Citrobacter species and its carbonic anhydrase (CA). Intracellular CA was purified from Citrobacter freundii (CF; accession no: MH283871) isolated from limestone rock site in Kumaun region of Indian Himalaya studied for the sequestration of carbon dioxide and the formation of calcite. CF showed maximum CA enzyme activity at 11.3 EU/ml at pH 7.0 and 37 °C. Hydration of CO2 into carbonate was characterized by calcite phase of calcium carbonate using absorption spectroscopy and imaging technique. Purified CA showed a significantly high CO2 sequestration capacity of 230 mg CaCO3/mg of purified as compared to crude enzyme (50 mg CaCO3/ml of enzyme).

Bioremediation or microbial cooperation can improve the e-waste management process in a greener way. Every management strategy is concentrated upon the organic and inorganic portion of the e-waste. Organic part consists of variety of thermo and thermosetting plastic with the presence of halogenated material. Microbes are involved in the process of dehalogenation in many ways. Microbes can manage the leaching of inorganic portion of e-waste which consists of both metallic and nonmetallic components.

Perturbations in various carbon pools like biological, geological, oceanic, and missing carbon sink affect its global data, which are generally neglected or ignored in routine calculations. These natural and anthropogenic events need to be considered before projecting a sustainable carbon management plan. These plans have both general and experimental aspects. General plans should focus on (a) minimizing emission; (b) maximizing environmentally sound reuse, reduce, and recycling; (c) effective treatment; and (d) converting carbon into valuable products with atom economy. Experimental carbon management plans involving various biological and chemical techniques with limitation in terms of research level and economic feasibility. Chemical options have benefits of higher productivity and wider product range, but it suffers from its higher-energy requirements and environmental unfriendliness. In contrast to this, biological options are more selective and less energy intensive, but their productivity is very low. Hence, there is a requirement of hybrid process where the benefits of both the options, i.e., biological and chemical, can be reaped. In view of above, the proposed review targets to highlight the various perturbations in the global carbon cycle and their effects; study the currently practiced options of carbon management, specifically in light of 3R principle; and propose various new hybrid methods by compatible combinations of chemical and biological processes to develop better and safer carbon management. These methods are hypothetical so they may require further research and validations but may provide a comprehensive base for developing such management methods.

Intradermal (ID) vaccination with modern cell culture rabies vaccines is a means to significantly reduce the cost of post-exposure prophylaxis as compared to intramuscular vaccination. In this study we evaluated the efficacy, immunogenicity and tolerability of PCECV and PVRV administered ID in doses of 0.1 mL per site according to the 2-site Thai Red Cross (TRC) regimen. Patients with WHO category III exposure to suspect or laboratory proven rabid animals were administered either PCECV (n = 58) or PVRV (n = 52) ID at a dose of 0.1 mL per site at two sites on days 0, 3 and 7 and at one site on days 30 and 90. Serum samples were withdrawn on days 0, 14, 30, 90 and 180 and rabies virus neutralizing antibody (RVNA) titers were determined by rapid fluorescent focus inhibition test (RFFIT). Patients who were exposed to laboratory confirmed rabid animals were followed up for one year after exposure. All 110 patients developed RVNA titers above 0.5 IU/mL by day 14. Adequate titers >0.5 IU/mL were maintained up to day 180. Both vaccines induced equivalent RVNA titers at all time points and were well tolerated. Five subjects who were bitten by laboratory confirmed rabid dogs were alive and healthy one year after exposure. As demonstrated, PCECV and PVRV are both immunogenic, efficacious and well tolerated when administered in the TRC post-exposure prophylaxis regimen in ID doses of 0.1 mL as recommended by WHO guidelines. The use of PCECV in this regimen may prove more economical in developing countries like India.

Multimodality therapy for esophageal cancer can cause various kinds of treatment-related sequelae, especially pulmonary toxicities. This prospective study aims to investigate the clinical and dosimetric parameters predicting lung injury in patients undergoing radiation therapy for esophageal cancer. Forty-five esophageal cancer patients were prospectively analyzed. The pulmonary toxicities (or sequelae) were evaluated by comparing chest X-ray films, pulmonary function tests and symptoms caused by pulmonary damage before and after treatment. All patients were treated with either three-dimensional radiotherapy (3DCRT) or with intensity-modulated radiotherapy (IMRT). The planning dose volume histogram was used to compute the lung volumes receiving more than 5, 10, 20 and 30 Gy (V5, V10, V20, V30) and mean lung dose. V20 was larger in the IMRT group than in the 3DCRT group (p = 0.002). V20 (>15%) and V30 (>20%) resulted in a statistically significant increase in the occurrence of chronic pneumonitis (p = 0.03) and acute pneumonitis (p = 0.007), respectively. The study signifies that a larger volume of lung receives lower doses because of multiple beam arrangement and a smaller volume of lung receives higher doses because of better dose conformity in IMRT plans. Acute pneumonitis correlates more with V30 values, whereas chronic pneumonitis was predominantly seen in patients with higher V20 values.