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Flue gas emissions are the waste gases produced during the combustion of fuel in industrial processes, which are released into the atmosphere. These identical processes also produce a significant amount of wastewater that is released into the environment. The current investigation aims to assess the viability of simultaneously mitigating flue gas emissions and remediating wastewater in a bubble column bioreactor utilizing bacterial consortia. A comparative study was done on different growth media prepared using wastewater. The highest biomass yield of 3.66 g L -1 was achieved with the highest removal efficiencies of 89.80, 77.30, and 80.77% for CO 2 , SO 2 , and NO, respectively. The study investigated pH, salinity, dissolved oxygen, and biochemical and chemical oxygen demand to assess their influence on the process. The nutrient balance validated the ability of bacteria to utilize compounds in flue gas and wastewater for biomass production. The Fourier Transform-Infrared Spectrometry (FT-IR) and Gas Chromatography-Mass Spectrometry (GC-MS) analyses detected commercial-use long-chain hydrocarbons, fatty alcohols, carboxylic acids, and esters in the biomass samples. The nuclear magnetic resonance (NMR) metabolomics detected the potential mechanism pathways followed by the bacteria for mitigation. The techno-economic assessment determined a feasible total capital investment of 245.74$ to operate the reactor for 288 h. The bioreactor's practicability was determined by mass transfer and thermodynamics assessment. Therefore, this study introduces a novel approach that utilizes bacteria and a bioreactor to mitigate flue gas and remediate wastewater., (© 2024. The Author(s).)

The bubble column reactor of 10 and 20 L capacity was designed to bio-mitigate 10% CO 2 (g) with 90% air utilizing thermophilic bacteria (Bacillus cereus SSLMC2). The maximum biomass yield during the growth phase was obtained as 9.14 and 10.78 g L -1 for 10 and 20 L capacity, respectively. The maximum removal efficiency for CO 2 (g) was obtained as 56% and 85% for the 10 and 20 L reactors, respectively. The FT-IR and GC-MS examination of the extracellular and intracellular samples identified value-added products such as carboxylic acid, fatty alcohols, and hydrocarbons produced during the process. The total carbon balance for CO 2 utilization in different forms confirmed that B. cereus SSLMC2 utilized 1646.54 g C in 10 L and 1587 g of C in 20 L reactor out of 1696.13 g of total carbon feed. The techno-economic assessment established that the capital investment required was $286.21 and $289.08 per reactor run of 11 days and $0.167 and $0.187 per gram of carbon treated for 10 and 20 L reactors, respectively. The possible mechanism pathways for bio-mitigating CO 2 (g) by B. cereus SSLMC2 were also presented utilizing the energy reactions. Hence, the work presents the novelty of utilizing thermophilic bacteria and a bubble column bioreactor for CO 2 (g) bio-mitigation., (© 2024. The Author(s).)

Comparative characterization of microRNA-mediated stress regulatory networks in contrasting rice cultivars is critical to decipher plant stress response. Consequently, a multi-level comparative analysis, using sRNA sequencing, degradome analysis, enzymatic and metabolite assays and metal ion analysis, in drought tolerant and sensitive rice cultivars was conducted. The study identified a group of miRNAs "Cultivar-specific drought responsive" (CSDR)-miRNAs (osa-miR159f, osa-miR1871, osa-miR398b, osa-miR408-3p, osa-miR2878-5p, osa-miR528-5p and osa-miR397a) that were up-regulated in the flag-leaves of tolerant cultivar, Nagina 22 (N22) and Vandana, but down-regulated in the sensitive cultivar, Pusa Basmati 1 (PB1) and IR64, during drought. Interestingly, CSDR-miRNAs target several copper-protein coding transcripts like plantacyanins, laccases and Copper/Zinc superoxide dismutases (Cu/Zn SODs) and are themselves found to be similarly induced under simulated copper-starvation in both N22 and PB1. Transcription factor OsSPL9, implicated in Cu-homeostasis also interacted with osa-miR408-3p and osa-miR528-5p promoters. Further, N22 flag leaves showed lower SOD activity, accumulated ROS and had a higher stomata closure. Interestingly, compared to PB1, internal Cu levels significantly decreased in the N22 flag-leaves, during drought. Thus, the study identifies the unique drought mediated dynamism and interplay of Cu and ROS homeostasis, in the flag leaves of drought tolerant rice, wherein CSDR-miRNAs play a pivotal role.

MicroRNAs regulate a spectrum of developmental and biochemical processes in plants and animals. Thus, knowledge of the entire miRNome is essential to understand the complete regulatory schema of any organism. The current study attempts to unravel yet undiscovered miRNA genes in rice. Analysis of small RNA libraries from various tissues of drought-tolerant 'aus' rice variety Nagina 22 (N22) identified 71 novel miRNAs. These were validated based on precursor hairpin structure, small RNA mapping pattern, 'star' sequence, conservation and identification of targets based on degradome data. While some novel miRNAs were conserved in other monocots and dicots, most appear to be lineage-specific. They were segregated into two different classes based on the closeness to the classical miRNA definition. Interestingly, evidence of a miRNA-like cleavage was found even for miRNAs that lie beyond the classical definition. Several novel miRNAs displayed tissue-enriched and/or drought responsive expression. Generation and analysis of the degradome data from N22 along with publicly available degradome identified several high confidence targets implicated in regulation of fundamental processes such as flowering and stress response. Thus, discovery of these novel miRNAs considerably expands the dimension of the miRNA-mediated regulation in rice.

Sub-QTLs and multiple intra-QTL genes are hypothesized to underpin large-effect QTLs. Known QTLs over gene families, biosynthetic pathways or certain traits represent functional gene-clusters of genes of the same gene ontology (GO). Gene-clusters containing genes of different GO have not been elaborated, except in silico as coexpressed genes within QTLs. Here we demonstrate the requirement of multiple intra-QTL genes for the full impact of QTL qDTY12.1 on rice yield under drought. Multiple evidences are presented for the need of the transcription factor 'no apical meristem' (OsNAM12.1) and its co-localized target genes of separate GO categories for qDTY12.1 function, raising a regulon-like model of genetic architecture. The molecular underpinnings of qDTY12.1 support its effectiveness in further improving a drought tolerant genotype and for its validity in multiple genotypes/ecosystems/environments. Resolving the combinatorial value of OsNAM12.1 with individual intra-QTL genes notwithstanding, identification and analyses of qDTY12.1has fast-tracked rice improvement towards food security.