Investigation of the Role of the Calvin Cycle and C1 Metabolism during HCHO Metabolism in Gaseous HCHO-Treated Petunia under Light and Dark Conditions Using<sup>13</sup>C-NMR

Shah

et al. 2023

Environ Sci Pollut Res

Volatile organic compounds (VOCs) such as formaldehyde and benzene are among the key contributors to indoor air pollution. The current situation of environmental pollution is alarming, where especially the indoor air pollution is becoming challenge as affecting the plants and humans. VOCs are known to adversely affect indoor plants such as causing necrosis and chlorosis. In order to withstand these organic pollutants, plants are naturally equipped with antioxidative defense system. The current research study was aimed to evaluate the combined effect of formaldehyde and benzene on antioxidative response of selected indoor plants namely Chlorophytum, Dracaena and Ficus. After the combined application of different levels (2, 2; 2, 4; 4, 2 & 4, 4 ppm) of formaldehyde and benzene in an airtight glass chamber, the enzymatic and non-enzymatic antioxidants were analyzed. Analysis of various non enzymatic assays showed signi cant increase in the total phenolics to 10.72 mgGAE/g in Ficus; Chlorophytum (9.20 mgGAE/g) & Dracaena (8.74 mgGAE/g) as compared to their respective controls i-e, 3.76, 5.39 & 6.07 mgGAE/g. Total avonoids in Ficus were also increased to1545.72 µg/g from 724 µg/g (in control) followed by 322.66 µg/g in Dracaena (control having only 167.11 µg/g) while total carotenoids content also increased in Dracaena (0.67 mg/g) followed by Chlorophytum (0.63 mg/g) while increasing the combined dose as compared to their control plants having only 0.62 and 0.24 mg/g content. The maximum increase in enzymatic antioxidants including total antioxidants (87.89%), catalase (59.21 U/mg) and guaiacol peroxidase (52.16 U/mg) was observed in Dracaena plant under combined dose of benzene (2 ppm) and formaldehyde (4 ppm). Although the experimental indoor plants have been reported to metabolize the indoor pollutants, but the current ndings indicate that both benzene and formaldehydes are also affecting the physiology of indoor plants.

Section: Discussionsupporting

confidence: 92%

Evaluating the antioxidative defense response of selected indoor plants against benzene and formaldehyde

Shah

et al. 2023

Environ Sci Pollut Res

“…During light reaction, sunlight was utilized by chlorophyll pigments to synthesize the high-energy compounds ATP and NADPH (Armbruster et al, 2017). The Calvin cycle is a lightindependent redox reaction to fix carbon dioxide into the sugar glucose molecules and gaseous detoxification during photosynthesis (Sun et al, 2015;Nowicka and Kruk, 2018). Repression of genes involved in photosynthetic components were reported in tea (Shi et al, 2019), hibiscus (Paredes and Quiles, 2015), and rice (Liu et al, 2018b) under LT stress.…”

Section: Role Of Photosynthesis System In Lt Stress Responsementioning

confidence: 99%

Genome-wide transcriptome profiling revealed biological macromolecules respond to low temperature stress in Brassica napus L

et al. 2022

Brassica napus L. (B. napus) is a vital oilseed crop cultivated worldwide; low temperature (LT) is one of the major stress factors that limit its growth, development, distribution, and production. Even though processes have been developed to characterize LT-responsive genes, only limited studies have exploited the molecular response mechanisms in B. napus. Here the transcriptome data of an elite B. napus variety with LT adaptability was acquired and applied to investigate the gene expression profiles of B. napus in response to LT stress. The bioinformatics study revealed a total of 79,061 unigenes, of which 3,703 genes were differentially expressed genes (DEGs), with 2,129 upregulated and 1,574 downregulated. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis pinpointed that the DEGs were enriched in LT-stress-responsive biological functions and metabolic pathways, which included sugar metabolism, antioxidant defense system, plant hormone signal transduction, and photosynthesis. Moreover, a group of LT-stress-responsive transcription factors with divergent expression patterns under LT was summarized. A combined protein interaction suggested that a complex interconnected regulatory network existed in all detected pathways. RNA-seq data was verified using real-time quantitative polymerase chain reaction analysis. Based on these findings, we presented a hypothesis model illustrating valuable information for understanding the LT response mechanisms in B. napus.

Over-expression of the Arabidopsis formate dehydrogenase in chloroplasts enhances formaldehyde uptake and metabolism in transgenic tobacco leaves

Wang

Zeng

Guo

et al. 2017

Planta

Over-expression of AtFDH controlled by the promoter of Rubisco small subunit in chloroplasts increases formaldehyde uptake and metabolism in tobacco leaves. Our previous study showed that formaldehyde (HCHO) uptake and resistance in tobacco are weaker than in Arabidopsis. Formate dehydrogenase in Arabidopsis (AtFDH) is a key enzyme in HCHO metabolism by oxidation of HCOOH to CO, which enters the Calvin cycle to be assimilated into glucose. HCHO metabolic mechanism in tobacco differs from that in Arabidopsis. In this study, AtFDH was over-expressed in the chloroplasts of transgenic tobacco using a light inducible promoter. C-NMR analysis showed that the carbon flux from HCHO metabolism was not introduced into the Calvin cycle to produce glucose in transgenic tobacco leaves. However, the over-expression of AtFDH significantly enhanced the HCHO metabolism in transgenic leaves. Consequently, the productions of [4-C]Asn, [3-C]Gln, [U-C]oxalate, and HCOOH were notably greater in transgenic leaves than in non-transformed leaves after treatment with HCHO. The increased stomatal conductance and aperture in transgenic leaves might be ascribed to the increased yield of oxalate in the guard cells with over-expressed AtFDH in chloroplasts. Accordingly, the transgenic plants exhibited a stronger capacity to absorb gaseous HCHO. Furthermore, the higher proline content in transgenic leaves compared with non-transformed leaves under HCHO stress might be attributable to the excess formate accumulation and Gln production. Consequently, the HCHO-induced oxidative stress was reduced in transgenic leaves.