pHA

高色氨酸血症
  • 文章类型: Journal Article
    聚羟基链烷酸酯(PHA)的工业生产面临着一些限制,这些限制阻碍了它们对传统塑料的竞争力,主要是由于高生产成本和复杂的回收过程。微生物生物技术的创新为克服这些挑战提供了有希望的解决方案。生物合成途径的修改是主要策略之一;允许直接的碳通量朝向PHA形成,增加聚合物积累和改善聚合物性能。此外,已经实施了扩大PHA生产中使用的可再生基质的范围的技术。这些原料廉价且丰富,但需要昂贵且能量密集的预处理。通过消除预处理的需要,并使这些原材料能够直接使用,微生物生物技术旨在降低生产成本。此外,改善下游过程以促进生物质从培养液中的分离和PHA的回收是至关重要的。改变细胞形态并允许PHA直接分泌到培养基中的遗传修饰简化了提取和纯化过程。显著降低运营成本。微生物生物技术的这些进步不仅提高了PHA的高效和可持续生产,但也将这些生物聚合物定位为石油基塑料的可行和有竞争力的替代品,促进循环经济,减少对化石资源的依赖。
    The industrial production of polyhydroxyalkanoates (PHAs) faces several limitations that hinder their competitiveness against traditional plastics, mainly due to high production costs and complex recovery processes. Innovations in microbial biotechnology offer promising solutions to overcome these challenges. The modification of the biosynthetic pathways is one of the main tactics; allowing for direct carbon flux toward PHA formation, increasing polymer accumulation and improving polymer properties. Additionally, techniques have been implemented to expand the range of renewable substrates used in PHA production. These feedstocks are inexpensive and plentiful but require costly and energy-intensive pretreatment. By removing the need for pretreatment and enabling the direct use of these raw materials, microbial biotechnology aims to reduce production costs. Furthermore, improving downstream processes to facilitate the separation of biomass from culture broth and the recovery of PHAs is critical. Genetic modifications that alter cell morphology and allow PHA secretion directly into the culture medium simplify the extraction and purification process, significantly reducing operating costs. These advances in microbial biotechnology not only enhance the efficient and sustainable production of PHAs, but also position these biopolymers as a viable and competitive alternative to petroleum-based plastics, contributing to a circular economy and reducing the dependence on fossil resources.
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  • 文章类型: Journal Article
    一生中,动物必须保持体内平衡,同时应对具有挑战性的事件。生殖后的时期对于卵生雌性来说,维持体内平衡可能是一个挑战,因为它们将大部分能量存储引导到卵黄发生,可能会增加对压力源的脆弱性。糖皮质激素(GC)分泌的变化每天促进各种行为和生理调整,并在面对压力源后恢复平衡。然而,当GC长时间升高时,通常发生在长期暴露于压力源的反应中,它们可以影响进食行为并抑制免疫功能。我们旨在阐明慢性皮质酮(CORT)暴露对摄食行为的影响,雌性蜥蜴的身体状况和免疫功能,CatalalanensisTropidurus,在后生殖时期。将30只动物分成三组:1.对照(未进行实验程序);2.空植入物(植入空硅橡胶管的动物);和3.CORT植入物(动物植入填充有硅橡胶管的CORT,长期连续释放至少一周)。CORT血浆水平摄食行为,身体状况(身体指数[BI]和脂肪指数[FI]),白细胞计数,和几个免疫功能变量(细菌杀伤能力[BKA],血凝滴度,评估了植物血凝素[PHA]免疫攻击和白细胞计数)。植入后,经CORT处理的动物通过实验保持稳定的体重,而对照组和空植入物组显示体重减轻。在CORT治疗的动物中,BI和FI之间也存在正相关关系,与第1组和第2组相比,FI更高。未观察到CORT对摄食行为或免疫功能的影响。
    Throughout life, animals must maintain homeostasis while coping with challenging events. The period after reproduction can be challenging for oviparous females to maintain homeostasis since they direct most of their energy stores to vitellogenesis, possibly increasing the vulnerability to stressors. Changes in glucocorticoids\' (GC) secretion promote various behavioural and physiological adjustments daily and to restore balance after facing stressors. However, when GC are elevated for extended periods, which usually occurs in response to chronic exposure to stressors, they can affect feeding behaviour and suppress the immune function. We aim to elucidate the effects of chronic corticosterone (CORT) exposure on feeding behaviour, body condition and immune function in female lizards, Tropidurus catalanensis, in the post-reproductive period. Thirty animals were divided into three groups: 1. Control (no experimental procedure performed); 2. Empty Implant (animals implanted with empty silastic tube); and 3. CORT Implant (animals implanted with silastic tube filled with CORT, with a chronic continuous release for at least a week). CORT plasma levels feeding behaviour, body condition (body index [BI] and fat index [FI]), leukocyte count, and several immune function variables (bacterial killing ability [BKA], hemagglutination titer, phytohemagglutinin [PHA] immune challenge and leukocyte count) were evaluated. After implantation, CORT treated animals maintained stable body mass through the experiment, while Control and Empty Implant groups displayed weight loss. In the CORT treated animals, there was also a positive relation between BI and FI, and higher FI when compared to groups 1 and 2. No effects of CORT were observed on feeding behaviour nor on the immune function.
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  • 文章类型: Journal Article
    构建具有双配体的新型纳米载体,以实现优异的抗肿瘤功效和较低的毒副作用。
    采用薄膜水化法制备脂质体。紫外线,高效液相色谱法,纳米尺寸分析仪,超滤离心,透析,透射电子显微镜,流式细胞术,细胞计数试剂盒-8,共聚焦激光扫描显微镜,transwell,和肿瘤球体测定法用于研究其特征,细胞毒性,和体外靶向dg-Bcan靶向肽(BTP-7)/pHA-替莫唑胺(TMZ)/四(4-羧基苯基)卟啉(TCPP)-Lip。
    BTP-7/pHA-TMZ/TCPP-Lip是一个球体,平均直径为143±3.214nm,多分散指数为0.203±0.025,表面电荷为-22.8±0.425mV。载药量(TMZ和TCPP)为7.40±0.23%和2.05±0.03%(mg/mg);包封效率为81.43±0.51%和84.28±1.64%(mg/mg)。结果表明,BTP-7/pHA-TMZ/TCPP-Lip具有增强的靶向性和细胞毒性。
    BTP-7/pHA-TMZ/TCPP-Lip可以特异性靶向肿瘤细胞,实现高效的药物输送,提高抗肿瘤疗效,降低全身毒性。
    UNASSIGNED: To construct a novel nano-carrier with dual ligands to achieve superior anti-tumour efficacy and lower toxic side effects.
    UNASSIGNED: Liposomes were prepared by thin film hydration method. Ultraviolet, high performance liquid chromatography, nano-size analyser, ultrafiltration centrifugation, dialysis, transmission electron microscope, flow cytometry, Cell Counting Kit-8, confocal laser scanning microscopy, transwell, and tumorsphere assay were used to study the characterisations, cytotoxicity, and in vitro targeting of dg-Bcan targeting peptide (BTP-7)/pHA-temozolomide (TMZ)/tetra(4-carboxyphenyl)porphyrin (TCPP)-Lip.
    UNASSIGNED: BTP-7/pHA-TMZ/TCPP-Lip was a spheroid with a mean diameters of 143 ± 3.214 nm, a polydispersity index of 0.203 ± 0.025 and a surface charge of -22.8 ± 0.425 mV. The drug loadings (TMZ and TCPP) are 7.40 ± 0.23% and 2.05 ± 0.03% (mg/mg); and the encapsulation efficiencies are 81.43 ± 0.51% and 84.28 ± 1.64% (mg/mg). The results showed that BTP-7/pHA-TMZ/TCPP-Lip presented enhanced targeting and cytotoxicity.
    UNASSIGNED: BTP-7/pHA-TMZ/TCPP-Lip can specifically target the tumour cells to achieve efficient drug delivery, and improve the anti-tumour efficacy and reduces the systemic toxicity.
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  • 文章类型: Journal Article
    随着细菌对常规抗生素耐药性的增加,迫切需要开发新的抗菌药物。用于递送这些药剂的传统生物材料通常难以在保持非细胞毒性特性的同时实现持续释放。在这项研究中,我们提出了一种创新的方法,使用细菌聚羟基链烷酸酯(PHA)作为抗微生物剂的载体,专门设计用于伤口愈合的应用。盐酸奥替尼啶(OCT),一种广泛使用的抗菌剂,作为我们的模型药物。为了达到所需的OCT释放和低细胞毒性的平衡,我们介绍了一种新型的生物衍生添加剂,3-羟基十五烷酸(3OHC15),从细菌中提取。该添加剂显著改善了PHA膜的亲水性,导致OCT的增强和持续释放。重要的是,添加剂不会对材料的拉伸强度或热性能产生不利影响。增加的OCT释放导致针对革兰氏阴性和阳性菌株两者的抗菌活性的改善。最值得注意的是,在PHA中掺入3OHC15减轻了释放的药物对人成纤维细胞的细胞毒性作用,确保生物相容性。这项工作代表了设计生物活性化合物的生物材料的新策略,在功效和细胞相容性之间实现关键的平衡,并标志着抗微生物递送系统领域的重大进步。
    With the increased occurrence of bacteria resistance to conventional antibiotics, the development of novel antimicrobials is urgently needed. Traditional biomaterials used for delivering these agents often struggle to achieve sustained release while maintaining non-cytotoxic properties. In this study, we present an innovative approach using bacterial polyhydroxyalkanoates (PHA) as a carrier for antimicrobial delivery, specifically designed for wound healing applications. Octenidine dihydrochloride (OCT), a widely used antimicrobial agent, served as our model drug. To achieve the desired balance of OCT release and low cytotoxicity, we introduced a novel bio-derived additive, 3-hydroxy-pentadecanoic acid (3OHC15), extracted from bacteria. This additive significantly improved the hydrophilicity of PHA films, resulting in enhanced and sustained release of OCT. Importantly, the additive did not adversely affect the material\'s tensile strength or thermal properties. The increased OCT release led to improved antibacterial activity against both Gram-negative and -positive strains. Most notably, the incorporation of 3OHC15 in PHA mitigated the cytotoxic effects of the released drug on human fibroblasts, ensuring biocompatibility. This work represents a novel strategy in the design of biomaterials for the delivery of bioactive compounds, achieving a critical balance between efficacy and cytocompatibility, and marks a significant advancement in the field of antimicrobial delivery systems.
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  • 文章类型: Journal Article
    聚羟基链烷酸酯(PHA)是微生物用于能量和碳储存的细胞内生物聚合物。化学提取时,它们在机械上类似于石化塑料,但完全可生物降解。虽然它们有潜力替代石化塑料,他们使用传统碳源的高生产成本仍然是一个重大挑战。一种潜在的解决方案是修饰异养PHA产生菌株以利用替代碳源。另一种方法是利用甲基营养或自养菌株。本文概述了用于PHA生产的细菌菌株,特别关注干细胞团中PHA含量最高的那些。菌株根据其碳源利用率进行组织,包括自养(利用CO2,CO)和甲基营养(利用减少的单碳底物)到异养(利用更传统和替代的底物)。
    Polyhydroxyalkanoates (PHAs) are intracellular biopolymers that microorganisms use for energy and carbon storage. They are mechanically similar to petrochemical plastics when chemically extracted, but are completely biodegradable. While they have potential as a replacement for petrochemical plastics, their high production cost using traditional carbon sources remains a significant challenge. One potential solution is to modify heterotrophic PHA-producing strains to utilize alternative carbon sources. An alternative approach is to utilize methylotrophic or autotrophic strains. This article provides an overview of bacterial strains employed for PHA production, with a particular focus on those exhibiting the highest PHA content in dry cell mass. The strains are organized according to their carbon source utilization, encompassing autotrophy (utilizing CO2, CO) and methylotrophy (utilizing reduced single-carbon substrates) to heterotrophy (utilizing more traditional and alternative substrates).
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  • 文章类型: Case Reports
    背景:Parry-Romberg综合征(PRS)是一种病因不明的罕见进行性退行性疾病。本文报道1例罕见的PRS合并晶状体半脱位在复旦大学眼耳鼻喉科医院,上海。据我们所知,这是上海首例报告的PRS合并晶状体半脱位病例,通过超声乳化和CTR放置以及IOL植入手术治疗。
    方法:一名60岁女性因“右侧视觉模糊2年”被转诊,自12岁起患有病因不明的持续性右侧面瘫。她有右面部肌肉萎缩和瘫痪。眼部检查还显示右眼睑假性上下垂,眼球内陷,右眼存在年龄相关性白内障合并晶状体半脱位。患者被诊断为年龄相关性白内障和右眼晶状体半脱位以及进行性半面神经萎缩(Parry-Romberg综合征)。我们进行了联合超声乳化手术,全麻下患者行IOL和CTR植入及瞳孔成形术,术后UCVA为20/30,随访1年。
    结论:这里我们报道了一例罕见的PHA合并晶状体半脱位病例。经过适当的眼科手术,患者在右眼取得满意的视力结果。
    BACKGROUND: Parry-Romberg syndrome (PRS) is a rare progressive degenerative disorder of unknown etiology. Here we report a rare case of PRS combined with lens subluxation in Eye and ENT hospital of Fudan University, Shanghai. To our knowledge, it is the first reported case of PRS combined with lens subluxation that has been managed surgically with phacoemulsification and CTR placement and IOL implantation in Shanghai.
    METHODS: A 60-year-old woman was referred for \"right visual blur for 2 years\" and had persistent right facial paralysis of unknown etiology since the age 12. She had right facial muscle atrophy and paralysis. Eye examination also showed the right eyelid pseudoptosis, enophthalmos, age-related cataract combined with lens subluxation existed in the right eye. The patient was diagnosed as age-related cataract and lens subluxation in the right eye and progressive hemifacial atrophy (Parry-Romberg syndrome). We conducted a combined phacoemulsification, IOL and CTR implantation and pupilloplasty surgery for the patient under general anesthesia and the postoperative UCVA was 20/30 and remained for 1 year\'s follow up.
    CONCLUSIONS: Here we reported a rare case of PHA combined with lens subluxation in China. After appropriate eye surgery, the patient achieved satisfying vision result in the right eye.
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    文章类型: Journal Article
    这项研究比较了从2018年健康相关行为调查(HRBS)和定期健康评估(PHA)调查中获得的烟草和尼古丁使用的患病率和危险因素的估计。HRBS和PHA是国防部从美国军人那里收集的有关健康行为的重要数据来源。虽然它们的收集方法不同,一些调查问题是相似的,这提供了一个比较调查估计的机会。与HRBS相比,现役服务成员一致报告说,PHA中所有类型的烟草和尼古丁使用的患病率要低得多:香烟(11.1%vs.18.4%),电子烟(7.3%与16.2%),咀嚼烟草(9.7%与13.4%),任何烟草或尼古丁的使用(25.3%vs.37.8%),以及使用2种或更多的烟草或尼古丁产品(5.8%vs.17.4%)。烟草和尼古丁使用以及人口统计学和其他行为变量之间的关联非常相似,包括年龄,性别,教育,种族和民族,等级,酒精的使用。与服务部门的协会,身体质量指数,和睡眠不一致。这项研究的结果表明,随着时间的推移,PHA可以提供有关军事烟草和尼古丁使用趋势的及时信息,但是机密的估计要高得多,本研究报告的自愿性HRBS表明,指令型PHA可能大大低估了所有类型烟草和尼古丁使用的患病率。
    This study compared estimates of the prevalence of and risk factors for tobacco and nicotine use obtained from the 2018 Health Related Behaviors Survey (HRBS) and Periodic Health Assessment (PHA) survey. The HRBS and the PHA are important Department of Defense sources of data on health behavior collected from U.S. military service members. While their collection methods differ, some survey questions are similar, which provides an opportunity to compare survey estimates. Active duty service members consistently reported a much lower prevalence of all types of tobacco and nicotine use on the PHA compared to the HRBS: cigarettes (11.1% vs. 18.4%), e-cigarettes (7.3% vs. 16.2%), chewing tobacco (9.7% vs. 13.4%), any tobacco or nicotine use (25.3% vs. 37.8%), and use of 2 or more tobacco or nicotine products (5.8% vs. 17.4%). Associations between tobacco and nicotine use as well as demographic and other behavioral variables were fairly similar, including age, sex, education, race and ethnicity, rank, and alcohol use. The associations with service branch, body mass index, and sleep were inconsistent. This results of this study suggest that the PHA can provide timely information on trends in military tobacco and nicotine use over time, but much higher estimates from the confidential, voluntary HRBS reported in this study suggest that the command-directed PHA may substantially underestimate the prevalence of all types of tobacco and nicotine use.
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  • 文章类型: Journal Article
    气候变化和塑料污染可能是21世纪环境面临的最重要的挑战。开发用于将甲烷(CH4)生物转化为聚羟基链烷酸酯(PHA)的具有成本效益的技术可以同时减少CH4排放并促进可生物降解聚合物的商业化。尽管温度的作用,氮剥夺,CH4:O2比例或微量营养素的可用性对甲烷营养生物的PHA积累能力进行了仔细探索,在成为未来生物精炼厂中的可行平台之前,仍然需要优化CH4到PHA的生物转化过程。在这项研究中,不同培养液pH值(5.5、7、8.5和10)对细菌生物量生长的影响,CH4生物转化率,在氮剥夺条件下,在搅拌釜生物反应器中研究了PHA的积累能力和细菌群落结构。较高的CH4消除率在增加的pH,在pH8.5时观察到最大值为50.4±2.7gCH4·m-3·h-1。这可能是由矿物介质中增加的离子强度介导的,增强了气液传质。有趣的是,在pH降低时观察到更高的PHB积累,在pH5.5时记录到最高的PHB含量(43.7±3.4%w·w-1)。低pH对II型嗜甲烷细菌生长的强选择压力可以解释这一发现。在pH5.5和7时,Methylocystis属的丰度分别从34%增加到85%和90%。相反,在pH8.5(14%)富集的社区中,甲基球菌的丰度较低。细胞内PHB作为能量和碳储存材料的积累允许在完全氮剥夺后48小时内维持高CH4生物降解率。此处获得的结果首次证明了pH对CH4向PHA的生物转化性能的关键和多因素作用。
    Climate change and plastic pollution are likely the most relevant challenges for the environment in the 21st century. Developing cost-effective technologies for the bioconversion of methane (CH4) into polyhydroxyalkanoates (PHAs) could simultaneously mitigate CH4 emissions and boost the commercialization of biodegradable polymers. Despite the fact that the role of temperature, nitrogen deprivation, CH4:O2 ratio or micronutrients availability on the PHA accumulation capacity of methanotrophs has been carefully explored, there is still a need for optimization of the CH4-to-PHA bioconversion process prior to becoming a feasible platform in future biorefineries. In this study, the influence of different cultivation broth pH values (5.5, 7, 8.5 and 10) on bacterial biomass growth, CH4 bioconversion rate, PHA accumulation capacity and bacterial community structure was investigated in a stirred tank bioreactor under nitrogen deprivation conditions. Higher CH4 elimination rates were obtained at increasing pH, with a maximum value of 50.4 ± 2.7 g CH4·m-3·h-1 observed at pH 8.5. This was likely mediated by an increased ionic strength in the mineral medium, which enhanced the gas-liquid mass transfer. Interestingly, higher PHB accumulations were observed at decreasing pH, with the highest PHB contents recorded at a pH 5.5 (43.7 ± 3.4 %w·w-1). The strong selective pressure of low pH towards the growth of Type II methanotrophic bacteria could explain this finding. The genus Methylocystis increased its abundance from 34 % up to 85 and 90 % at pH 5.5 and 7, respectively. On the contrary, Methylocystis was less abundant in the community enriched at pH 8.5 (14 %). The accumulation of intracellular PHB as energy and carbon storage material allowed the maintenance of high CH4 biodegradation rates during 48 h after complete nitrogen deprivation. The results here obtained demonstrated for the first time a crucial and multifactorial role of pH on the bioconversion performance of CH4 into PHA.
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  • 文章类型: Journal Article
    埃克托因,一种在嗜盐菌中适应盐的关键渗透保护剂,对化妆品和医疗行业越来越感兴趣。然而,其生产仍然受到模型微生物中严格的发酵过程和其本地生产者的低生产水平的挑战。这里,我们通过过表达ectABC操纵子,系统地设计了天然的ectoine生产商Halomonasbluphagenesis用于生产ectoine,增加前体的可用性,增强产品运输系统并优化其生长培养基。在没有质粒的情况下,在7L生物反应器中开放式无菌孵育下,最终的工程化H.bluphagenesis在52小时内产生了85g/L的ectoine,抗生素或诱导剂。此外,成功地证明了通过工程化的H.bluphagenesis将盐浓度与外胎合成脱钩以及与生物塑料P(3HB-co-4HB)共同生产的可行性。未灭菌的发酵过程和显着增加的外泌素滴度表明H.bluphagenesis作为下一代工业生物技术(NGIB)的底盘,不仅可以用于细胞内生物塑料PHA的生物制造,还可以用于小分子化合物的生物制造。
    Ectoine, a crucial osmoprotectant for salt adaptation in halophiles, has gained growing interest in cosmetics and medical industries. However, its production remains challenged by stringent fermentation process in model microorganisms and low production level in its native producers. Here, we systematically engineered the native ectoine producer Halomonas bluephagenesis for ectoine production by overexpressing ectABC operon, increasing precursors availability, enhancing product transport system and optimizing its growth medium. The final engineered H. bluephagenesis produced 85 g/L ectoine in 52 h under open unsterile incubation in a 7 L bioreactor in the absence of plasmid, antibiotic or inducer. Furthermore, it was successfully demonstrated the feasibility of decoupling salt concentration with ectoine synthesis and co-production with bioplastic P(3HB-co-4HB) by the engineered H. bluephagenesis. The unsterile fermentation process and significantly increased ectoine titer indicate that H. bluephagenesis as the chassis of Next-Generation Industrial Biotechnology (NGIB), is promising for the biomanufacturing of not only intracellular bioplastic PHA but also small molecular compound such as ectoine.
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  • 文章类型: Journal Article
    塑料污染是我们这个时代最大的环境问题。微塑料和纳米塑料等细分产品不可避免地进入食物链,并带来前所未有的健康风险。在这种情况下,生物基和可生物降解的塑料替代品已获得动力,旨在弥合向更可持续的未来过渡。聚羟基链烷酸酯(PHA)是少数通过生物技术路线100%合成的热塑性聚合物之一,可在常见的自然环境中完全生物降解。聚(羟基丁酸酯-羟基己酸酯)[P(HB-co-HHx)]是一种PHA共聚物,在商品聚合物行业中具有巨大潜力,因为它的机械性能可以通过微调其摩尔HHx含量来定制。我们最近开发了一种策略,该策略能够可靠地调整P(HB-co-HHx)的单体含量。然而,通常缺乏对PHA的材料特性的全面研究,以评估它们是否实际上模仿了常规塑料的功能。我们对具有低至中等羟基己酸酯含量的P(HB-co-HHx)共聚物进行了详细研究,以了解HHx单体含量如何影响热和机械性能,并将其与非生物降解联系起来。通过在2-14mol%的范围内增加HHx分数,随着共聚物的熔融温度(Tm)玻璃化温度(Tg)从Tm165°C降低到126°C,我们赋予了加工窗口和应用范围的扩展。Tg4°C至-5.9°C,伴随着结晶度从54%降低到20%。在14摩尔%HHx含量下,断裂伸长率从5.7%增加到703%,确认所检查的范围足够大以获得延性和脆性共聚物,而拉伸强度在整个研究范围内保持不变。最后,随着HHx分数的增加,在12小时内从70%降低到55%,加速的非生物降解速度减慢。
    Plastic pollution is the biggest environmental concern of our time. Breakdown products like micro- and nano-plastics inevitably enter the food chain and pose unprecedented health risks. In this scenario, bio-based and biodegradable plastic alternatives have been given a momentum aiming to bridge a transition towards a more sustainable future. Polyhydroxyalkanoates (PHAs) are one of the few thermoplastic polymers synthesized 100 % via biotechnological routes which fully biodegrade in common natural environments. Poly(hydroxybutyrate-co-hydroxyhexanoate) [P(HB-co-HHx)] is a PHA copolymer with great potential for the commodity polymers industry, as its mechanical properties can be tailored through fine-tuning of its molar HHx content. We have recently developed a strategy that enables for reliable tailoring of the monomer content of P(HB-co-HHx). Nevertheless, there is often a lack of comprehensive investigation of the material properties of PHAs to evaluate whether they actually mimic the functionalities of conventional plastics. We present a detailed study of P(HB-co-HHx) copolymers with low to moderate hydroxyhexanoate content to understand how the HHx monomer content influences the thermal and mechanical properties and to link those to their abiotic degradation. By increasing the HHx fractions in the range of 2 - 14 mol%, we impart an extension of the processing window and application range as the melting temperature (Tm) and glass temperature (Tg) of the copolymers decrease from Tm 165 °C to 126 °C, Tg 4 °C to -5.9 °C, accompanied by reduced crystallinity from 54 % to 20 %. Elongation at break was increased from 5.7 % up to 703 % at 14 mol% HHx content, confirming that the range examined was sufficiently large to obtain ductile and brittle copolymers, while tensile strength was maintained throughout the studied range. Finally, accelerated abiotic degradation was shown to be slowed down with an increasing HHx fraction decreasing from 70 % to 55 % in 12 h.
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