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The issue of non-degradable petroleum-based plastic waste is a global challenge that requires urgent attention due to its harmful impact on humans and the environment. Biomass-based materials have garnered significant attention to address this challenge in recent times. Lignin, with its abundance, low price, and rich aromatic groups, is not only essential biomass but also a crucial material that can be utilized to produce biodegradable polymers. This review paper provides comprehensive knowledge of the synthesis and applications related to lignin, polyester, and lignin–polyester copolymers with a specific focus on organic polymer synthesis techniques and diverse applications. Beginning with lignin, the review explores various extraction methods from raw biomass resources aimed at enhancing its compatibility with polyester matrices. Next, we discuss lignin chemical modification methods that alter its chemical structure and properties, ultimately enhancing its integration with polyesters. Subsequently, the synthesis of polyester is examined, encompassing condensation polymerizations and ring-opening polymerizations. These methods are evaluated for their scalability and capability in producing tailored polymer chains suitable for copolymerization with lignin. The copolymerization strategies involving lignin and polyester are explored in detail, including graft-onto and graft-from approaches. Each method is discussed for its ability to control copolymer composition and properties, which are crucial for achieving desired material characteristics. In terms of applications, the review highlights the wide-ranging utility of lignin–polyester copolymers across industries such as packaging, construction, and separation. These polymers offer improved biodegradability, thermal stability, and mechanical strength compared to conventional polyesters, making them perfect candidates for novel sustainable materials. Overall, this review provides valuable insights into the synthesis methods and applications of lignin, polyester, and lignin–polyester copolymers offering a comprehensive overview of their potential for addressing environmental concerns and expanding the scope of lignin-derived materials in various industrial applications. [ABSTRACT FROM AUTHOR]

Pears constitute an essential temperate crop and are primarily produced through interspecific hybridization owing to self-incompatibility that complicates their breeding history. To address this, we sequenced the complete chloroplast (cp) genomes of 18 Pyrus and one Malu s species using the Illumina HiSeq4000 platform. The cp genomes ranged from 159,885 bp to 160,153 bp and exhibited a conserved circular DNA structure with an average GC content of 36.5%. Each cp genome contained 127 genes, including 83 protein-coding, 36 tRNA, and 8 rRNA genes. Divergence analysis with mVISTA showed high conservation in the coding regions and notable variations in the non-coding regions. All species shared 17 intron-containing genes, with ycf3 and clpP each having two introns. Five intron-containing genes (ndhB , rpl2 , rps12 , trnA-UGC , and trnE-UUC) were located in the inverted repeat regions, while trnL-UAA was located in the large single-copy region, with conserved intron lengths across Pomoideae. We identified polymorphic intron sequences in the rpl22 , petB , clpP , ndhA , and rps16 genes and designed primers for these regions. Notably, the two Pyrus ussuriensis accessions Doonggeullebae and Cheongdangrori showed intron-length polymorphisms despite being classified as the same species. Phylogenetic analysis of the cp genome sequences revealed two major clusters, indicating distinct maternal lineages and evolutionary origins. This study underscores the importance of cp gene polymorphisms in P. fauriei , P. calleryana , P. ussuriensis , and P. pyrifolia , providing valuable insights into Pyrus evolution as well as aiding in the conservation and breeding of pear germplasm. [ABSTRACT FROM AUTHOR]

This work highlights the conversion method of chaining up greenhouse gas CO2 with biomass lignin to develop new sustainable, recyclable polymers from abundant and non‐food based renewable resources. A cyclic carbonate monomer has synthesized using a cost‐effective, non‐phosgene‐based, and greener approach under atmospheric pressure and room temperature. The fully programable ring‐opening polymerization is accomplished by varying the catalyst (DBU and TBD), catalyst loading (0.5–5.0%) and reaction time (2–40 min). The best polymer is obtained in 1% TBD with a 30‐min reaction. The precise characterization of the synthesized cyclic carbonate monomer and polymers' structure are established using spectroscopic analyses including 1H, 13C, and 2D HSQC NMR, FT‐IR, and GPC. The new polymers exhibit high molecular weights (Mn: 120.34–154.58 kDa) and adequate thermal stabilities (Td5%: 244–277 °C from TGA and Tg: 33–52 °C from DSC), rendering them advantageous for practical applications. Significantly, the CO2 and lignin‐based polymers have successfully recycled to the monomer for a circular plastic economy by heating at 90 °C for 12 h in the presence of DBU. This process yields original monomers for another polymerization without unwanted changes in chemical structures, presenting an ultimate sustainable solution. [ABSTRACT FROM AUTHOR]

Physiological response and transcriptome changes were observed to investigate the effects on the growth, metabolism and genetic changes of Pinus densiflora grown for a long time in an environment with an elevated atmospheric CO2 concentration. Pine trees were grown at ambient (400 ppm) and elevated (560 ppm and 720 ppm) CO2 concentrations for 10 years in open-top chambers. The content of nonstructural carbohydrates was significantly increased in elevated CO2. It was notable that the contents of chlorophylls significantly decreased at an elevated CO2. The activities of antioxidants were significantly increased at an elevated CO2 concentration of 720 ppm. We analyzed the differences in the transcriptomes of Pinus densiflora at ambient and elevated CO2 concentrations and elucidated the functions of the differentially expressed genes (DEGs). RNA-Seq analysis identified 2415 and 4462 DEGs between an ambient and elevated CO2 concentrations of 560 ppm and 720 ppm, respectively. Genes related to glycolysis/gluconeogenesis and starch/sucrose metabolism were unchanged or decreased at an elevated CO2 concentration of 560 ppm and tended to increase at an elevated CO2 concentration of 720 ppm. It was confirmed that the expression levels of genes related to photosynthesis and antioxidants were increased at an elevated CO2 concentration of 720 ppm. [ABSTRACT FROM AUTHOR]