Tree species composition, growing stock and biomass carbon dynamics of the major timber species in Hindu Kush regions of Pakistan / Composição de espécies de árvores, estoque em crescimento e dinâmica de biomassa de carbono das principais espécies madeireiras nas regiões de Indocuche no Paquistão

Using inventory data, this study evaluates the species composition, growing stock volume (GSV), and biomass carbon (BMC) of the five major timber species in the sub-tropical, and temperate/sub-alpine regions of Pakistan. It was found that the stem density varies between 50 and 221 trees ha -1, with a mean of 142 trees ha-1 (13.68 million trees for entire forest area). Among the species, Pinus wallichiana showed a high species composition (27.80%) followed by Picea smithiana (24.64%). The GSV was found in the range of 67.81 to 425.94 m3 ha-1, with a total GSV value of 20.68 million m3 for the entire region. Similarly, The BMC ranged from 27.04 to 169.86 Mg ha-1, with a mean BMC value of 86.80 Mg ha-1. The total amount of stored carbon was found at 8.69 million tons for a total of 95842 ha of commercially managed forest. Furthermore, the correlation analysis between the basal area (BA) and GSV and BMC showed that BA is the best predictor of GSV and BMC. The findings provide insights to the policy makers and forest managers regarding the sustainable commercial forest management as well as forest carbon management in the recent global carbon management for climate change mitigation.

Usando dados de inventário, este estudo avaliou a composição de espécies, volume de estoque crescente (GSV) e carbono de biomassa (BMC) das cinco principais espécies madeireiras nas regiões subtropicais e temperadas/subalpinas do Paquistão. Constatou-se que a densidade do caule variou entre 50 e 221 árvores ha-1, com média de 142 árvores ha-1 (13,68 milhões de árvores para toda a área florestal). Entre as espécies, Pinus wallichiana apresentou alta composição de espécies (27,80%), seguida de Picea smithiana (24,64%). O GSV foi encontrado na faixa de 67,81 a 425,94 m3 ha-1, com um valor total de 20,68 milhões de m3 para toda a região. Da mesma forma, o BMC variou de 27,04 a 169,86 mg ha-1, com valor médio de 86,80 mg ha-1. A quantidade total de carbono armazenado foi de 8,69 milhões de toneladas para um total de 95.842 ha de floresta manejada comercialmente. Além disso, a análise de correlação entre área basal (BA), GSV e BMC mostrou que BA é o melhor preditor de GSV e BMC. As descobertas fornecem insights para os formuladores de políticas e gestores florestais sobre o manejo florestal comercial sustentável, bem como o manejo florestal de carbono no recente gerenciamento global de carbono para a mitigação das mudanças climáticas.

Progress and future perspective of epidemiological research of air pollution and climate change in the context of achieving carbon peaking and carbon neutrality goals / 中华流行病学杂志

Climate change is the great health challenge for human beings in the 21st century. Air pollution is also an important public health problem worldwide. China announced the climate commitment to achieve carbon peaking by 2030 and carbon neutrality by 2060. Achieving these goals would not only have far-reaching effects on air pollution control and climate change, but also improve the population health in China. Air pollution and climate change epidemiology are important aspects of environmental epidemiology. In this paper, we discuss the current status and future development of epidemiological research of air pollution and climate change in the context of achieving carbon peaking and carbon neutrality goals to provide ideas and suggestions for environmental and health studies in the future.

Microorganisms used for bioleaching of metals from typical solid wastes and their leaching mechanism: a review / 生物工程学报

Typical solid wastes contain many metal resources, which are worthy of recycling. The bioleaching of typical solid waste is affected by multiple factors. Green and efficient recovery of metals based on the characterization of leaching microorganisms and the elucidation of leaching mechanisms may contribute to the implementation of China's "dual carbon" strategic goals. This paper reviews various types of microorganisms used for leaching metals from typical solid wastes, analyzes the action mechanism of metallurgical microorganisms, and prospects the application of metallurgical microorganisms to facilitate the application of metallurgical microorganisms in typical solid wastes.

Measures for waste and by-product recycling and circular economy of whole industry chain of traditional Chinese medicine resources facing carbon peak and carbon neutrality (dual carbon) goals / 中国中药杂志

It has become a common consensus that resource conservation and intensive recycling for improving resource utilization efficiency is an important way to achieve carbon peak and carbon neutrality(dual carbon). Traditonal Chinese medicine(TCM)resources as national strategic resources are the material basis and fundamental guarantee for the development of TCM industry and health services. However, the rapid growth of China's TCM industry and the continuous expansion and extension of the industrial chain have exposed the low efficiency of TCM resources. Resource waste and environmental pollution caused by the treatment and discharge of TCM waste have emerged as major problems faced by the development of the industry, which has aroused wide concern. Considering the dual carbon goals, this paper expounds the role and potential of TCM resource recycling and circular economy industry development. Taking the typical model of TCM resource recycling as the case of circular economy industry in reducing carbon source and increasing carbon sink, this paper puts forward the suggestions for the TCM circular economy industry serving the double carbon goals. The suggestions mainly include strengthening the policy and strategic leading role of the double carbon goals, building an objective evaluation system of low-carbon emission reduction in the whole industrial chain of TCM resources, building an industrial demonstration park for the recycling of TCM resources, and promoting the establishment of a circular economy system of the whole industrial chain of TCM resources. These measures are expected to guide the green transformation of TCM resource industry from linear economic model to circular economy model, provide support for improving the utilization efficiency and sustainable development of TCM resources, and facilitate the low-carbon and efficient development of TCM resource industry and the achievement of the double carbon goals.

The degradation of plastics and the production of polyhydroxyalkanoates (PHA) / 生物工程学报

In recent years, the petroleum-based plastic pollution problem has been causing global attention. The idea of "degradation and up-cycling of plastics" was proposed for solving the environmental pollution caused by non-degradable plastics. Following this idea, plastics would be firstly degraded and then reconstructed. Polyhydroxyalkanoates (PHA) can be produced from the degraded plastic monomers as a choice to recycle among various plastics. PHA, a family of biopolyesters synthesized by many microbes, have attracted great interest in industrial, agricultural and medical sectors due to its biodegradability, biocompatibility, thermoplasticity and carbon neutrality. Moreover, the regulations on PHA monomer compositions, processing technology, and modification methods may further improve the material properties, making PHA a promising alternative to traditional plastics. Furthermore, the application of the "next-generation industrial biotechnology (NGIB)" utilizing extremophiles for PHA production is expected to enhance the PHA market competitiveness, promoting this environmentally friendly bio-based material to partially replace petroleum-based products, and achieve sustainable development with carbon-neutrality. This review summarizes the basic material properties, plastic upcycling via PHA biosynthesis, processing and modification methods of PHA, and biosynthesis of novel PHA.

Preface for special issue on chemical bioproduction / 生物工程学报

Engineering efficient enzymes or microbial cell factories should help to establish green bio-manufacturing process for chemical overproduction. The rapid advances and development in synthetic biology, systems biology and enzymatic engineering accerleate the establishing feasbile bioprocess for chemical biosynthesis, including expanding the chemical kingdom and improving the productivity. To consolidate the latest advances in chemical biosynthesis and promote green bio-manufaturing, we organized a special issue on chemical bioproduction that including review or original research papers about enzymatic biosynthesis, cell factory, one-carbon based biorefinery and feasible strategies. These papers comprehensively discussed the latest advaces, the challenges as well as the possible solutions in chemical biomanufacturing.

Genetic modification of acetogens and optimization of fermentation process in C1-gas bioconversion / 生物工程学报

The current linear economy model relies on fossil energy and increases CO2 emissions, which contributes to global warming and environmental pollution. Therefore, there is an urgent need to develop and deploy technologies for carbon capture and utilization to establish a circular economy. The use of acetogens for C1-gas (CO and CO2) conversion is a promising technology due to high metabolic flexibility, product selectivity, and diversity of the products including chemicals and fuels. This review focuses on the physiological and metabolic mechanisms, genetic and metabolic engineering modifications, fermentation process optimization, and carbon atom economy in the process of C1-gas conversion by acetogens, with the aim to facilitate the industrial scale-up and carbon negative production through acetogen gas fermentation.

Efficient synthesis of L-methionine by engineering the one carbon module of Escherichia coli / 生物工程学报

L-methionine, also known as L-aminomethane, is one of the eight essential amino acids required by the human body and has important applications in the fields of feed, medicine, and food. In this study, an L-methionine high-yielding strain was constructed using a modular metabolic engineering strategy based on the M2 strain (Escherichia coli W3110 ΔIJAHFEBC/PAM) previously constructed in our laboratory. Firstly, the production of one-carbon module methyl donors was enhanced by overexpression of methylenetetrahydrofolate reductase (methylenetetrahydrofolate reductase, MetF) and screening of hydroxymethyltransferase (GlyA) from different sources, optimizing the one-carbon module. Subsequently, cysteamine lyase (hydroxymethyltransferase, MalY) and cysteine internal transporter gene (fliY) were overexpressed to improve the supply of L-homocysteine and L-cysteine, two precursors of the one-carbon module. The production of L-methionine in shake flask fermentation was increased from 2.8 g/L to 4.05 g/L, and up to 18.26 g/L in a 5 L fermenter. The results indicate that the one carbon module has a significant impact on the biosynthesis of L-methionine, and efficient biosynthesis of L-methionine can be achieved through optimizing the one carbon module. This study may facilitate further improvement of microbial fermentation production of L-methionine.

Characterization the response of Chlamydomonas reinhardtii serine/threonine protein kinase mutant to blue light / 生物工程学报

In order to investigate the molecular mechanism of silk/threonine protein kinase (STK)-mediated blue light response in the algal Chlamydomonas reinhardtii, phenotype identification and transcriptome analysis were conducted for C. reinhardtii STK mutant strain crstk11 (with an AphvIII box reverse insertion in stk11 gene coding region) under blue light stress. Phenotypic examination showed that under normal light (white light), there was a slight difference in growth and pigment contents between the wild-type strain CC5325 and the mutant strain crstk11. Blue light inhibited the growth and chlorophyll synthesis in crstk11 cells, but significantly promoted the accumulation of carotenoids in crstk11. Transcriptome analysis showed that 860 differential expression genes (DEG) (559 up-regulated and 301 down-regulated) were detected in mutant (STK4) vs. wild type (WT4) upon treatment under high intensity blue light for 4 days. After being treated under high intensity blue light for 8 days, a total of 1 088 DEGs (468 upregulated and 620 downregulated) were obtained in STK8 vs. WT8. KEGG enrichment analysis revealed that compared to CC5325, the crstk11 blue light responsive genes were mainly involved in catalytic activity of intracellular photosynthesis, carbon metabolism, and pigment synthesis. Among them, upregulated genes included psaA, psaB, and psaC, psbA, psbB, psbC, psbD, psbH, and L, petA, petB, and petD, as well as genes encoding ATP synthase α, β and c subunits. Downregulated genes included petF and petJ. The present study uncovered that the protein kinase CrSTK11 of C. reinhardtii may participate in the blue light response of algal cells by mediating photosynthesis as well as pigment and carbon metabolism, providing new knowledge for in-depth analysis of the mechanism of light stress resistance in the algae.

An examination of the carbon metabolic pathways in Acinetobacter sp. TAC-1 in the context of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) utilization / 生物工程学报

The present study aimed to unravel the carbon metabolism pathway of Acinetobacter sp. TAC-1, a heterotrophic nitrification-aerobic denitrification (HN-AD) strain that utilizes poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) as a carbon source. Sodium acetate was employed as a control to assess the gene expression of carbon metabolic pathways in the TAC-1 strain. The results of genome sequencing demonstrated that the TAC-1 strain possessed various genes encoding carbon metabolic enzymes, such as gltA, icd, sucAB, acs, and pckA. KEGG pathway database analysis further verified the presence of carbon metabolism pathways, including the glycolytic pathway (EMP), pentose phosphate pathway (PPP), glyoxylate cycle (GAC), and tricarboxylic acid (TCA) cycle in the TAC-1 strain. The differential expression of metabolites derived from distinct carbon sources provided further evidence that the carbon metabolism pathway of TAC-1 utilizing PHBV follows the sequential process of PHBV (via the PPP pathway)→gluconate (via the EMP pathway)→acetyl-CoA (entering the TCA cycle)→CO2+H2O (generating electron donors and releasing energy). This study is expected to furnish a theoretical foundation for the advancement and implementation of novel denitrification processes based on HN-AD and solid carbon sources.

Structural characterization of PCP-Ⅰ from Poria as vaccine adjuvant and its hydrolytic oligosaccharide / 中国中药杂志

Poria is an important medical herb in clinic. The authors isolated a polysaccharide(PCP-Ⅰ) from Poria in previous studies, which is composed of galactose, mannose, fucose and glucose. PCP-Ⅰ exhibited significant adjuvant effects on H1N1 influenza vaccine, hepatitis B surface antigen and anthrax protective antigen, and its adjuvant activity was stronger than aluminium adjuvant. However, little is known about the chemical structure of PCP-Ⅰ at present. In this study, weak acid hydrolysis was used to obtain the backbone oligosaccharide of PCP-Ⅰ. Then periodate oxidation, Smith degradation, methylation analysis, Fourier transform infrared spectroscopy(FT-IR), nuclear magnetic resonance(NMR) and gas chromatography-mass spectrometry(GC-MS) were performed to investigate the chemical structural features of PCP-Ⅰ and its hydrolytic oligosaccharide(PCP-Ⅰ-hy-1). These results suggested that the backbone of PCP-Ⅰ was composed of galactose with α anomeric carbon and β anomeric carbon. The linking residues of galactan are(1→),(l→6) and(1→2,6).

Payment for ecosystem services (PES): a holistic tool for sustainable forest management-a case study from Pakistan / Pagamento por serviços ecossistêmicos (PES): uma ferramenta holística para o manejo florestal sustentável: um estudo de caso do Paquistão

Abstract Economic valuation of ecosystem services is a new concept in forest management. Economic valuation provides basis for payment for ecosystem services (PES). Therefore, objective of this study was to evaluate eco-tourism and carbon stock services of the Maindam valley, District Swat, Pakistan. For the carbon stock calculation, a sample size of 155 plots of 0.1 hectare (Ha) was taken using preliminary survey at 95% confidence interval and 10% allowable error. The data for tourism services was collected from owners of all the hotels, 100 tourists and key informants of the area at 10% sampling intensity on pretested questionnaire for twenty years period (1997-2017). Results showed that Miandam valley has carbon stock worth US$ 16,306,000 while the value of eco-tourism was US$ 1,578,458 on annual basis. The results also showed that trend of tourism has drastically declined after the 9/11 incident for foreigners and locals and the situation was further deteriorated during the era of Talibanization or militancy from 2008-2011. This study recommends implementation of PES strategy at the rate of 5%, thus a total of US$ 78,922 can be earned from eco-tourism and carbon crediting in the study area annually, which could play important role in sustainable forest management.

Resumo A valoração econômica dos serviços ecossistêmicos é um novo conceito no manejo florestal. A avaliação econômica fornece base para o pagamento por serviços ecossistêmicos (PES). Portanto, o objetivo deste estudo foi avaliar o ecoturismo e os serviços de estoque de carbono do vale de Miandam, distrito Swat, Paquistão. Para o cálculo do estoque de carbono, um tamanho de amostra de 155 parcelas de 0,1 hectare (ha) foi tirado, usando pesquisa preliminar com intervalo de confiança de 95% e erro admissível de 10%. Os dados para serviços de turismo foram coletados de proprietários de todos os hotéis, 100 turistas e informantes-chave da área em 10% de intensidade de amostragem em questionário pré-testado para um período de 20 anos (1997-2017). Os resultados mostraram que o vale de Miandam tem estoque de carbono no valor de US$ 16.306.000, enquanto o valor do ecoturismo foi de US$ 1.578.458 anualmente. Os resultados também mostraram que a tendência do turismo diminuiu drasticamente para estrangeiros e locais após o incidente de 11 de Setembro, e a situação se agravou ainda mais durante a era da talibanização ou militância de 2008-2011. Este estudo recomenda a implementação da estratégia de PES na taxa de 5%, portanto um total de US$ 78.922 pode ser ganho com ecoturismo e crédito de carbono na área de estudo anualmente, o que pode desempenhar um papel importante no manejo florestal sustentável.

Stoichioproteomics study of differentially expressed proteins and pathways in head and neck cancer / Estudo estequioproteômico de proteínas e vias expressas diferencialmente no câncer de cabeça e pescoço

Abstract Hypoxia is a prominent feature of head and neck cancer. However, the oxygen element characteristics of proteins and how they adapt to hypoxia microenvironments of head and neck cancer are still unknown. Human genome sequences and proteins expressed data of head and neck cancer were retrieved from pathology atlas of Human Protein Atlas project. Then compared the oxygen and carbon element contents between proteomes of head and neck cancer and normal oral mucosa-squamous epithelial cells, genome locations, pathways, and functional dissection associated with head and neck cancer were also studied. A total of 902 differentially expressed proteins were observed where the average oxygen content is higher than that of the lowly expressed proteins in head and neck cancer proteins. Further, the average oxygen content of the up regulated proteins was 2.54% higher than other. None of their coding genes were distributed on the Y chromosome. The up regulated proteins were enriched in endocytosis, apoptosis and regulation of actin cytoskeleton. The increased oxygen contents of the highly expressed and the up regulated proteins might be caused by frequent activity of cytoskeleton and adapted to the rapid growth and fast division of the head and neck cancer cells. The oxygen usage bias and key proteins may help us to understand the mechanisms behind head and neck cancer in targeted therapy, which lays a foundation for the application of stoichioproteomics in targeted therapy and provides promise for potential treatments for head and neck cancer.

Resumo A hipóxia é uma característica proeminente do câncer de cabeça e pescoço. No entanto, as características do elemento oxigênio das proteínas e como elas se adaptam aos microambientes de hipóxia do câncer de cabeça e pescoço ainda são desconhecidas. Sequências do genoma humano e dados expressos de proteínas de câncer de cabeça e pescoço foram recuperados do atlas de patologia do projeto Human Protein Atlas. Em seguida, comparou o conteúdo do elemento de oxigênio e carbono entre proteomas de câncer de cabeça e pescoço, e células epiteliais escamosas da mucosa oral normal, localizações do genoma, vias e dissecção funcional associada ao câncer de cabeça e pescoço também foram estudadas. Um total de 902 proteínas expressas diferencialmente foi observado onde o conteúdo médio de oxigênio é maior do que as proteínas expressas de forma humilde em proteínas de câncer de cabeça e pescoço. Além disso, o conteúdo médio de oxigênio das proteínas reguladas positivamente foi 2,54% maior do que das outras. Nenhum de seus genes codificadores foi distribuído no cromossomo Y. As proteínas reguladas positivamente foram enriquecidas em endocitose, apoptose e regulação do citoesqueleto de actina. O conteúdo aumentado de oxigênio das proteínas altamente expressas e reguladas pode ser causado pela atividade frequente do citoesqueleto e adaptado ao rápido crescimento e divisão das células cancerosas de cabeça e pescoço. O viés do uso de oxigênio e as proteínas-chave podem nos ajudar a entender os mecanismos por trás do câncer de cabeça e pescoço na terapia direcionada, o que estabelece uma base para a aplicação da estequioproteômica na terapia direcionada e oferece uma promessa para potenciais tratamentos para o câncer de cabeça e pescoço.

A pandemia de COVID-19 e o seu impacto à saúde planetária / The COVID-19 pandemic and its impact on planetary health

A pandemia de COVID-19 deu ao mundo uma imagem clara do que é uma crise multidimensional em escala planetária, revelando o papel central que ocupa o setor de saúde e as profundas desigualdades no acesso aos cuidados em saúde que existem entre os diferentes países, e dentro de cada um deles. Melhorar os efeitos ambientais do setor e reduzir as emissões de gases de efeito estufa pode não apenas melhorar a saúde de todos, mas também reduzir os custos com os cuidados em saúde. O setor de saúde de cada país libera direta e indiretamente gases de efeito estufa ao fornecer seus serviços e ao comprar produtos, serviços e tecnologias em uma cadeia de fornecimento de carbono intensivo. Educar os profissionais de saúde mais profundamente sobre os efeitos das mudanças climáticas pode levar a práticas clínicas mais sustentáveis, melhorando os resultados para os pacientes e fornecendo um impulso substancial para aumentar os esforços para reduzir as emissões de carbono. O setor da saúde deve assumir a responsabilidade por sua pegada climática respondendo à crescente emergência climática, não apenas prestando assistência aos doentes, feridos ou moribundos como resultado da crise climática e suas causas, mas também fazendo a prevenção primária e reduzindo drasticamente suas próprias emissões.

The COVID-19 pandemic has painted a clear picture of what a multidimensional planetary crisis is, revealing the central role played by the health sector and the deep inequalities in access to health care that exist between and within each country. Decreasing the environmental effects of the health sector and reducing greenhouse gas emission may not only improve people's health, but also reduce health care costs. The health care sectors around the world directly and indirectly release greenhouse gases by providing their services and purchasing products, services, and technologies within a carbon-intensive supply chain. Further educating health care professionals about the effects of climate change may lead to more sustainable clinical practices, improving patient outcomes and providing substantial impetus to increased efforts to reduce carbon emission. The health sector must take responsibility for its climate footprint by responding to the growing climate emergency not only by assisting the sick, injured, or dying from the climate crisis, but also by doing primary prevention and drastically reducing its own carbon emission.

Direct Synthesis of Bienzyme-like Carbide-derived Carbons via Mild Electrochemical Oxidation of Ti 3AlC 2 MAX / 生物医学与环境科学（英文）

Objective@#To develop effective alternatives to natural enzymes, it is crucial to develop nanozymes that are economical, resource efficient, and environmentally conscious. Carbon nanomaterials that have enzyme-like activities have been extensively developed as substitutes for traditional enzymes.@*Methods@#Carbide-derived carbons (CDCs) were directly synthesized via a one-step electrochemical method from a MAX precursor using an ammonium bifluoride electrolyte at ambient conditions. The CDCs were characterized by systematic techniques.@*Results@#CDCs showed bienzyme-like activities similar to that of peroxidase and superoxide dismutase. We systematically studied the dependence of CDC enzyme-like activity on different electrolytes and electrolysis times to confirm activity dependence on CDC content. Additionally, the synthesis mechanism and CDC applicability were elaborated and demonstrated, respectively.@*Conclusion@#The demonstrated synthesis strategy eliminates tedious intercalation and delamination centrifugation steps and avoids using high concentrations of HF, high temperatures, and halogen gases. This study paves the way for designing two-dimensional material-based nanocatalysts for nanoenzyme and other applications.

Engineering the glycogen metabolism in cyanobacterial photosynthetic cell factories: a review / 生物工程学报

Cyanobacteria are important photosynthetic autotrophic microorganisms and are considered as one of the most promising microbial chassises for photosynthetic cell factories. Glycogen is the most important natural carbon sink of cyanobacteria, playing important roles in regulating its intracellular carbon distributions. In order to optimize the performances of cyanobacterial photosynthetic cell factories and drive more photosynthetic carbon flow toward the synthesis of desired metabolites, many strategies and approaches have been developed to manipulate the glycogen metabolism in cyanobacteria. However, the disturbances on glycogen metabolism usually cause complex effects on the physiology and metabolism of cyanobacterial cells. Moreover, the effects on synthesis efficiencies of different photosynthetic cell factories usually differ. In this manuscript, we summarized the recent progress on engineering cyanobacterial glycogen metabolism, analyzed and compared the physiological and metabolism effects caused by engineering glycogen metabolism in different cyanobacteria species, and prospected the future trends of this strategy on optimizing cyanobacterial photosynthetic cell factories.

Engineering application of aerobic methane oxidizing bacteria (methanotrophs): a review / 生物工程学报

Aerobic methane oxidizing bacteria (methanotrophs) can use methane as carbon source and energy source, eliminating 10%-20% of global methane. Methanotrophs can also effectively synthesize valuable methane-derived products. This article introduced the methane oxidizing mechanism of methanotrophs, and summarized the practical application and research hotspots of methanotrophs in the field of methane emission reduction in the landfill, ventilation air methane mitigation in coal mines, valuable chemicals biosynthesis, as well as oil and gas reservoir exploration. Main factors influencing the pollutant removal and the biosynthesis efficiency in various applications were also discussed. Based on the study of large-scale cultivation of methanotrophs, some measures to benefit the application and promotion of aerobic methane oxidizing biotechnology were proposed. This includes investigating the effect of intermediate metabolites on methanotrophs activity and population structure, and exploiting economical and efficient alternative culture media and culture techniques.

Halomonas uses short-chain fatty acids to synthesize polyhydroxyalkanoates / 生物工程学报

Halomonas can grow on diverse carbon sources. As it can be used for unsterile fermentation under high-salt conditions, it has been applied as a chassis for next-generation industrial biotechnology. Short-chain volatile fatty acids, including acetate, propionate, and butyrate, can be prepared from biomass and are expected to be novel carbon sources for microbial fermentation. Halomonas sp. TD01 and TD08 were subjected to shaking culture with 10-50 g/L butyrate, and they were found to effectively synthesize poly-3-hydroxybutyrate with butyrate as the carbon source. The highest yield of poly-3-hydroxybutyrate was achieved at butyrate concentration of 20 g/L (9.12 g/L and 7.37 g/L, respectively). Butyrate at the concentration > 20 g/L inhibited cell growth, and the yield of poly-3-hydroxybutyrate decreased to < 4 g/L when butyrate concentration was 50 g/L. Moreover, Halomonas sp. TD08 can accumulate the copolymer of 3-hydroxybutyrate and 3-hydroxyvalerate by using propionate and butyrate as carbon sources. However, propionate was toxic to cells. To be specific, when 2 g/L propionate and 20 g/L butyrate were simultaneously provided, cell dry weight and polymer titer were 0.83 g/L and 0.15 g/L, respectively. The addition of glycerol significantly improved cell growth and boosted the copolymer titer to 3.95 g/L, with 3-hydroxyvalerate monomer content of 8.76 mol%. Short-chain volatile fatty acids would be promising carbon sources for the production of polyhydroxyalkanoates by Halomonas.

Identification and biological characteristics of a pathogen causing leaf blight of Rehmannia glutinosa / 中国中药杂志

Leaf blight outbroke in Rehmannia glutinosa plantation in Wenxian county, Henan province in 2019. R. glutinosa plants with diseased leaves were collected from the plantation, and three strains were isolated from the diseased leaf samples. Pathogenicity test, morphological observation, and phylogenetic analysis of ITS, EF1-α, and Tub suggested that they were respectively Fusarium proliferatum, F. oxysporum, and F.acuminatum. Among them, F. acuminatum, as a pathogen of R. glutinosa leaf disease, had never been reported. To clarify the biological characteristics of F. acuminatum, this study tested the influence of light, pH, temperature, medium, carbon source, and nitrogen source on the mycelial growth rate of the pathogen during a 5-day culture period, and explored the lethal temperature. The results showed that the mycelia grew well under the photoperiod of 12 h light/12 h darkness, at 5-40 ℃(optimal temperature: 25 ℃), at pH 4-11(optimal pH: 7.0), on a variety of media(optimal medium: oatmeal agar), and in the presence of diverse carbon and nitrogen sources(optimal carbon source: soluble starch; optimal nitrogen source: sodium nitrate). The lethal temperature was verified to be 51 ℃(10 min). The conclusion is expected to lay a scientific basis for diagnosis and control of R. glutinosa leaf diseases caused by F. acuminatum.

Research advances on the application of carbon dots in wound treatment / 中华烧伤杂志

Chronic and infectious wound healing has always been an issue of concern in clinical and scientific research, in which bacterial infection and oxidative damage are the key factors hindering wound healing. Carbon dots, as a new material, has attracted much attention because of its unique physical and chemical properties and good biological safety. In recent years, the researches on the antibacterial property, antioxidant, and photoluminescence properties of carbon dots are more and more extensive and carbon dots have great potential in the treatment of chronic and infectious wounds. This paper reviews the research progress of carbon dots in three aspects: antibacterial, anti-oxidation and monitoring of wound infection are reviewed, and further discusses its specific mechanism, potential research direction, and application prospect.