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To reduce environmental pollution and reliance on fossil resources, polyethylene terephthalate as the most consumed synthetic polyester needs to be recycled effectively. However, the existing recycling methods cannot process colored or blended polyethylene terephthalate materials for upcycling. Here we report a new efficient method for acetolysis of waste polyethylene terephthalate into terephthalic acid and ethylene glycol diacetate in acetic acid. Since acetic acid can dissolve or decompose other components such as dyes, additives, blends, etc., Terephthalic acid can be crystallized out in a high-purity form. In addition, Ethylene glycol diacetate can be hydrolyzed to ethylene glycol or directly polymerized with terephthalic acid to form polyethylene terephthalate, completing the closed-loop recycling. Life cycle assessment shows that, compared with the existing commercialized chemical recycling methods, acetolysis offers a low-carbon pathway to achieve the full upcycling of waste polyethylene terephthalate. The recycling of polyethylene terephthalate is of utmost importance to reduce environmental pollution and reliance on fossil resources however, the existing methods do not process colored or blended polyethylene terephthalate materials. Here, the authors demonstrate the acetolysis of waste polyethylene terephthalate into terephthalic acid and simultaneous acidic degradation of dyes and additives

Pollen and spore morphology provides essential taxonomic reference data for floristic and environmental studies in tropical regions, where modern comparative datasets remain limited. This study documents the morphological characteristics of pollen and spores recovered from a shallow soil profile in a degraded mixed deciduous forest within Sri Nan National Park, northern Thailand. Using a non-acetolysis extraction protocol and systematic sub-sampling of a 30-cm profile, pollen and spores representing 37 plant families were identified, including lycophytes, bryophytes, monilophytes, gymnosperms, and angiosperms. Spore-producing taxa, particularly monilophytes, dominate the assemblage, while angiosperm pollen includes both arboreal and non-arboreal elements. More than 100 morphotypes are described based on aperture type, exine ornamentation, size, and symmetry, supported by high-resolution photomicrographs and standardized morphotype descriptions. The resulting dataset expands the regional palynological reference framework for northern Thailand and tropical Southeast Asia and supports consistent taxonomic identification in palynological, floristic, and comparative paleoecological studies, particularly in human-impacted forest–agriculture mosaics.

Carbon fibre-reinforced polymers (CFRPs) are used in many applications in the global energy transition, including for lightweighting aircraft and vehicles and in wind turbine blades, shipping containers and gas storage vessels 1 , 2 , 3 – 4 . Given the high cost and energy-intensive manufacture of CFRPs 5 , 6 – 7 , recycling strategies are needed that recover intact carbon fibres and the epoxy-amine resin components. Here we show that acetic acid efficiently depolymerizes both aliphatic and aromatic epoxy-amine thermosets used in CFRPs to recoverable monomers, yielding pristine carbon fibres. Deconstruction of materials from multiple sectors demonstrates the broad applicability of this approach, providing clean fibres from 2 h reactions. The optimal conditions were scaled to 80.0 g of post-consumer CFRPs, and demonstrative composites were fabricated from the recycled carbon fibres, which were recycled two more times, maintaining their strength throughout. Process modelling and techno-economic analysis, with feedstock cost informed by wind turbine blade waste generation 8 , indicates this method is cost effective, with a minimum selling price of US$1.50 per kg for recycled carbon fibres whereas life cycle assessment shows process greenhouse gas emissions around 99% lower than virgin carbon fibre production. Overall, this approach could enable recycling of industrial CFRPs as it provides clean, mechanically viable recycled carbon fibres and recoverable resin monomers from the thermoset. Acetic acid efficiently depolymerizes aliphatic and aromatic epoxy-amine thermosets used in carbon fibre-reinforced polymers (CFRPs) to yield recoverable monomers and pristine carbon fibres, which, based on process modelling, techno-economic analysis and life cycle assessment, could enable industrial recycling of CFRPs.

This study investigates the diversity of forage plants and the pollen morphology associated with Apis dorsata in mangrove stands of the Mahakam Delta. The research applied the acetolysis method to analyze bee bread samples. From these samples, five plant families comprising seven species were identified, with pollen from Rhizophora apiculata found to be the most frequently collected by A. dorsata foragers. The pollen grains were generally medium to large in size, exhibiting oblate spheroidal to prolate spheroidal forms. They occurred as monads, with apertures categorized as tricolporate, inaperturate, and tricolpate. The surface ornamentation was characterized by scabrate, verrucate, and perforate textures.

Monitoring of airborne pollen concentrations provides an important source of information for the globally increasing number of hay fever patients. Airborne pollen is traditionally counted under the microscope, but with the latest developments in image recognition methods, automating this process has become feasible. A challenge that persists, however, is that many pollen grains cannot be distinguished beyond the genus or family level using a microscope. Here, we assess the use of Convolutional Neural Networks (CNNs) to increase taxonomic accuracy for airborne pollen. As a case study we use the nettle family (Urticaceae), which contains two main genera ( Urtica and Parietaria ) common in European landscapes which pollen cannot be separated by trained specialists. While pollen from Urtica species has very low allergenic relevance, pollen from several species of Parietaria is severely allergenic. We collect pollen from both fresh as well as from herbarium specimens and use these without the often used acetolysis step to train the CNN model. The models show that unacetolyzed Urticaceae pollen grains can be distinguished with > 98% accuracy. We then apply our model on before unseen Urticaceae pollen collected from aerobiological samples and show that the genera can be confidently distinguished, despite the more challenging input images that are often overlain by debris. Our method can also be applied to other pollen families in the future and will thus help to make allergenic pollen monitoring more specific.

The Muara Enim Formation is known as coal bearing formation. The abundant presence of coal in this Late Miocene formation indicates a terrestrial vegetation suited depositional environment. This research employed pollen analysis to identify the type of vegetation that existed during the formation of the upper Muara Enim Formation. Pollen was extracted from fine-sized lithology taken from field in Tanjung Agung area, South Sumatra Basin. Acetolysis treatment was applied to obtain pollen. The number of pollen fossils was calculated based on the total grains present at each research locations. There are species that categorised as abundant fossils which are Canarium indicum, Morus microphylla, Archontophoenix cunninghamiana, Tectaria brachiata, Pteris deflexa, Asplenium nidus, Polypodium vulgare dan Lycopodiella cernua. The most abundant fossils is Polypodium vulgare which is including into fern group. The second abundant fossils is Archontophoenix cunninghamiana which is including into angiosperm group. The vegetation present in abundance in the moss group is Lycopodiella cernua . Thus, it is known that the paleoenvironment of the research area is tropical rainforest and lowland forest at the research site.

The acetolysis technology for waste polyester fibers is characterized by simplicity, efficiency, and cost-effectiveness. However, challenges emerge when processing polyester-cotton blends, as the cotton component cannot endure more aggressive chemical conditions due to its distinct chemical properties. To overcome this, we now employ the concept of \"acetylation\" for a mild cotton-stripping pretreatment. During acetylation, the cotton component gradually dissolves in the acetic acid solution, forming a homogeneous solution, while the polyester fiber remains in solid form, thereby ensuring efficient separation (removal rate exceeding 90%). The entire process utilizes inexpensive bulk chemicals and is straightforward to operate. Given the similarity in the solvent system, this approach is termed the extended acetolysis system. Comprehensive techno-economic analysis and life cycle assessment indicate that, even when benchmarked against petroleum-based pricing, the extended acetolysis system can achieve economic viability alongside appreciable environmental benefits.

For many bacteria, including those important in pathogenesis, expression of a surface-localized capsular polysaccharide (CPS) can be critical for survival in host environments. In Gram-positive bacteria, CPS linkage is to either the cytoplasmic membrane or the cell wall. Despite the frequent occurrence and essentiality of these polymers, the exact nature of the cell wall linkage has not been described in any bacterial species. Using the Streptococcus pneumoniae serotype 2 CPS, which is synthesized by the widespread Wzy mechanism, we found that linkage occurs via the reducing end glucose of CPS and the β-D-N-acetylglucosamine (GlcNAc) residues of peptidoglycan (PG). Hydrofluoric acid resistance, 31P-NMR, and 32P labeling demonstrated the lack of phosphodiester bonds, which typically occur in PG–polysaccharide linkages. Component sugar analysis of purified CPS–PG identified only CPS and PG sugars in the appropriate ratios, suggesting the absence of an oligosaccharide linker. Time of flight mass spectrometry confirmed a direct glycosidic linkage between CPS and PG and showed that a single CPS repeat unit can be transferred to PG. The linkage was acetolysis susceptible, indicative of a 1,6 glycosidic bond between CPS and the GlcNAc C-6. The acetylation state of GlcNAc did not affect linkage. A direct glycosidic linkage to PG was also demonstrated for serotypes 8 and 31, whose reducing end sugars are glucose and galactose, respectively. These results provide the most detailed descriptions of CPS–PG linkages for any microorganism. Identification of the linkage is a first step toward identifying the linking enzyme and potential inhibitors of its activity.

This study aims to determine the types of feed pollen consumed by the bee species Tetragonula biroi . The research has the objective of providing information to the public regarding the sources of feed for T. biroi honey bees, which are located in Kuajang Village, Binuang District, Polewali Mandar Regency, West Sulawesi. The research was conducted between February and April 2020. A comparative method was employed to examine the shapes of plant pollen found around the meliponiary in comparison to the shapes of pollen discovered in honey and bee bread. Samples were prepared using the acetolysis method and stained using safranin. The research findings indicate the presence of 23 identified flowering plant species in the vicinity of the meliponiary, along with their identification in bee bread. However, only 12 species were identified in honey. Coconut pollen exhibited the highest percentage, accounting for 44.8% of honey and 38.13% of bee bread, categorizing it as a secondary pollen type.

The stable carbon isotope composition (δ13C) of plants and algae is influenced by environmental factors, such as pCO2, water availability, and altitude. To effectively use the δ13C of fossil material as a proxy for these parameters, it is essential to understand the chemical and isotopic effects of diagenesis and conventional chemical treatments. In this study, we subject various species of pollen and spores of higher plants to different chemical treatments simulating diagenesis and chemical alteration in the environment as well as palynological processing. We analyze changes in the molecular and isotopic composition using pyrolysis–gas chromatography–mass spectrometry (Py-GC-MS) and both elemental analyzer–isotope ratio mass spectrometry (EA-IRMS) and laser ablation–isotope ratio mass spectrometry (LA-IRMS), respectively. We find that saponification removes extractable and ester-bound lipids, which increases the δ13C value of the sporomorphs. Treatment with HF and HCl (HF–HCl) removed most hydrolyzable polysaccharides and proteins, causing a drop in δ13C values. Acetolysis produced aromatic-rich residual sporomorphs with the lowest δ13C values compared to other treatments, likely representing the diagenetically resistant sporopollenin polymer. These findings imply a successional depletion of 13C during fossil maturation, where aliphatic lipids are diagenetically removed in the process, until only the relatively 13C-depleted sporopollenin remains. To adequately compare fossil and extant sporomorph δ13C values, we advise the use of HF–HCl and a lipid removal step other than acetolysis as the palynological treatment, as acetolysis treats the material non-uniformly. Lastly, LA-IRMS shows promise for targeted isotopic analysis of individual specimens of various types of palynomorphs.