查看更多>>摘要：High concentration of reducing sugar from enzymatic hydrolysis of cellulose is the key for utilization of cellulose nowadays. Here, in-situ homogeneous enzymolysis of cellulose in supercritical carbon dioxide (SC-CO2) system by using cellulase modified with dextran (Cell-DEX) could resolve the above question. Cell-DEX can effectively hydrolyze cellulose in SC-CO2 system, and the yield of reducing sugar reaches 242 mg/g cellulose. At the same time, the effects of the modified site, molecular weight of modifier and degree of substitution, stability of Cell-DEX were discussed. Then the enzymolysis of corn straw was also studied in this system and the efficiency has been greatly improved. Therefore, it is an effective way to use cellulose sustainably.
查看更多>>摘要：Biomolecules present in natural materials have always remained a prime choice for the development of safe, protective, and wellness-related textile products. In this study, functional microcapsules were prepared using the chitosan-gelatin complex as a shell material and rosemary essential oil as a core material. The prepared mi-crocapsules were utilized for the development of multifunctional linen fabric. The oil release mechanism of microcapsules was studied using the Korsmeyer-Peppas model. The obtained microcapsules and finished linen fabrics were characterized using SEM-EDX analysis and ATR-FTIR analysis. The durability of functionalities against repeated launderings was also studied. The microcapsules with an encapsulation efficiency of more than 70% were used to impart durable mosquito-repellency (more than 90%) against Anopheles mosquitoes, anti-bacterial properties against E. coli (> 93%) and S. aureus (> 95%) bacteria, significant (> 91%) antioxidant activity and a pleasant aroma. The chemical constituents of rosemary oil were also found to be responsible for imparting multifunctional properties. The novel combination of biopolymers and essential oil was explored for the development of multifunctional textiles.
查看更多>>摘要：The facile preparation of rice husk-derived green coagulant (RHC) via water-based heatless and salt-free technique has been attempted. The coagulating activity for the practical treatment of urban and agricultural runoffs has been examined with respect to the indicator parameters, specifically turbidity, total suspended solids (TSS) and chemical oxygen demand (COD), and optimized according to the effects of coagulant dosage, solution pH, temperature, settling time and stirring speed. The morphological characteristics, elemental composition and surface functionalities of RHC were detected by scanning electron microscopy, energy dispersive X-ray analysis and Fourier transform infrared spectroscopy, respectively, while the fundamental governing mechanism was postulated. The polymeric chains of polysaccharides and proteins within RHC, notably the pendant O-and N bearing moieties, were accounted for the coagulative effect with the colloidal particulates, predominantly via sorption, charge neutralization and interparticle bridging interactions. The treatment performance compared favorably against the reported biomass-derived coagulants, in terms of both coagulating potential and environmental sustainability. The viable role of rice husk as a renewable resource for the preparation of an effective, green coagulant has been successfully presented.
Salehi, MaryamBahmankar, MoslemNaghavi, Mohammad RezaCornish, Katrina...
9页
查看更多>>摘要：Natural rubber (NR) has unique properties which are unmatched by synthetic rubber and is used in over 50,000 products. The only commercial source of NR is the Para rubber tree (Hevea brasiliensis) which is insecure because of increasing demand, price instability, high labor costs, trade politics, competition with other crops, deforestation bans preventing new H. brasiliensis acreage, and disease. Taraxacum kok-saghyz, rubber root dandelion, produces NR quite similar to that from H. brasiliensis. One of the major challenges in turning T. kok-saghyz into an industrial rubber-bearing crop is the lack of an environmentally friendly and cost-effective process for rubber extraction proven at commercial scale. Rubber in T. kok-saghyz is present as latex and solid rubber threads. If the latex form is not required, the better option is to recover all the NR as solid rubber after drying the roots. This review summarizes latex extraction (flow and blender methods) and solid rubber extraction (wet milling, enzyme digestion, solvent extraction, and dry milling processes) from T. kok-saghyz and their effects on NR yield and quality (molecular weight and purity). The current challenges and future perspectives for improving T. koksaghyz NR extraction processes are discussed.
查看更多>>摘要：Biodiesel is a renewable biobased fuel obtained from transesterification of plant seed oil with methanol. This fuel has physical properties that make it attractive as an alternative fuel for compression-ignition (diesel) engines. In the United States (US), there is a need to increase the production of sustainable and environmentally friendly biofuels, including biodiesel, to supplement fossil fuels. To meet these challenges, emphasis is being placed on expanding the use of low-cost non-food oils as feedstocks for biodiesel. Low-erucic acid pennycress (LEAP) was developed from field pennycress as a cover crop for use in the Upper Midwestern US. The objective of the present study was to convert LEAP oil to biodiesel (fatty acid methyl esters [FAME]) and evaluate its fuel properties. The same process was applied to FAME made from natural field pennycress (FPC) oil as a baseline for comparison of results. The LEAP oil-FAME (LEAP-ME) had a kinematic viscosity at 40 degrees C (KV40) that was lower than that of FPC oil-FAME (FPC-ME), and nearly equivalent to the KV40 of soybean oil-FAME (SME). The total saturated-FAME (SFAME) concentration of LEAP-ME (5.40 mass%) was greater than that of FPC-ME. Since SFAME have high melting points, this caused LEAP-ME to have a higher cloud point (CP) than FPC-ME. However, the CP of LEAP ME (-6.8 degrees C) was lower than those of canola oil-FAME (CaME; -2.5 degrees C) and SME (-2.8 degrees C). The oxidative induction period at 110 degrees C (IP110) of LEAP-ME was poor (0.83 h), indicating that it would need to be treated with antioxidants before distribution as an alternative diesel fuel.
查看更多>>摘要：Dichroa febrifuga has been used in traditional Chinese medicine for centuries to treat productive cough and fevers caused by malaria infection, however the antimicrobial activity is still unknown. In this study, the crude alka-loids extract of D. febrifuga leaves showed potent anti-oomycete activity against phytopathogen Phytophthora capsici. Subsequent bioassay-guided fractionation led to identify febrifugine as the main active component. Febrifugine showed specific in vitro anti-oomycete activity against P. capsici, Phytophthora sojae and Phytophthora infestans with EC50 of 1.741, 1.674 and 0.413 mu g/mL, respectively, but showed no or weak antifungal activity against twelve test phytopathogenic fungi. Scanning electron microscope and optical microscope results indi-cated that febrifugine could alter the morphology of P. infestans hyphae, but did not destroy the cell wall. The electrical conductivity and intracellular component leakage experiments suggested the integrity of the cell membrane after the treatment of febrifugine. Moreover, febrifugine possessed inhibitory effects on zoospore release and germination of P. infestans. In vivo bioassay using detached leaves demonstrated that febrifugine had better protective and curing activities than commercialized drug metalaxyl. The application of febrifugine at a dose of 60 mu g/mL provided protective efficacies of 93.1% and 91.9%, and curing efficacies of 86.2% and 86.6% for pepper phytophthora blight and potato late blight, respectively. Taken together, this study showed that the crude alkaloids extract of D. febrifuga and its active component febrifugine represent alternatives to control plant diseases caused by oomycetes, and febrifugine is expected to be a new leading structure for the development of oomyceticides.
Pino-Otin, Maria RosaNavarro, JulianaVal, JonatanRoig, Francisco...
11页
查看更多>>摘要：Despite the current popularity of herbal and flower hydrolates and the multiple applications found in the food, wood, pharmaceutical, pesticide, perfume, cosmetic, and aromatherapy industries, the effect of hydrolates in the environment is poorly known. This study evaluates the ecotoxicity of the Satureja montana L. hydrolate on water and soil bioindicators and also on the fluvial periphyton mesocosms for a more ecological point of view. The acute toxicity of the fresh water invertebrate Daphnia magna, the bacteria Vibrio fisheri, and the earthworm Eisenia fetida, was quantified as well as the phytotoxic effect on the plant Allium cepa L. Communities of river periphyton were used to study the impact of the hydrolate on the freshwater ecosystems. The taxonomic study of these communities revealed a rich diversity of diatoms. The hydrolate of S. montana showed a high ecotoxicity at very low percentages of hydrolate in all organisms tested and in the periphyton communities. The LC50 varies from 0.05% to 4.25%, with a clear dose-dependent relationship. The effect of the hydrolate in decreasing order was: A.cepa > D. magna > V. fisheri > periphyton > E. fetida. The strong phytotoxic effect on A. cepa allows exploring possible uses of the hydrolate as a bio-herbicide. The Gas Chromatography Mass Spectrometry (GC-MS) characterisation of the hydrolate reveals 1 alcohol and 6 terpenes. Carvacrol (89.03%) and thymol (6.66%) are the volatile compounds found in the highest proportion, products that have multiple biological properties and known synergistic effects, which could explain the high bioactivity of the hydrolate. Our study suggests that S. montana hydrolate could impact different trophic levels of the river ecosystems and can affect the soil functions affecting earthworms due its powerful bioactivity on a wide range of non-target organisms even in complex communities such as the fluvial periphyton. Therefore, although hydrolates can become a good alternative to synthetic products, the use of these products is not free of environmental risks and their release to the environment should be evaluated.
查看更多>>摘要：As abundant, biodegradable, and biocompatible materials, polysaccharides have received great attention in many fields. Ionic conductive hydrogels based on sodium alginate and its derivatives have been extensively studied in the field of wearable sensors due to their low cost, non-toxic and biocompatible. However, the inherent low mechanical strength of hydrogels leads to poor accuracy and durability of electrical signals under high loads. Herein, the intelligent ionic hydrogels based on oxide sodium alginate (OSA), poly (acrylamide-co-acrylic acid) (PACA), and FeCl3 were synthesized by a simple one-pot method. Reversible imine and hydrogen bonds between OSA and PACA, and coordination interactions among PACA, OSA, and Fe3+ were successfully designed to provide hydrogels with excellent elongation at break (830%), strong tensile strength (370 kPa), and high self-healing efficiency (90%). They also show controlled conductivity and high tensile sensitivity (Gauge factor, GF=7.8) for accurate and stable detection of human movement and physiological stimuli. Given these findings, the developed polysaccharide-based hydrogels represent a great application prospect in strain sensors for wearable electronic devices, soft robotics, and human-machine interfaces.
查看更多>>摘要：The integration of Bacillus thuringiensis (Bt) genes is often accompanied by unintended effects along with the improved resistance to targeted pests. The insertion information of transfer DNA (T-DNA) and the expression information of upstream and downstream genes are of great significance for related research on unexpected effects and molecular-level mechanisms. In this study, six dual Bt transgenic Populus x euramericana cv. Neva (poplar 107) lines were used as research objects. We determined growth and physiological indices, and characterized the T-DNA integration using next-generation sequencing technology. The transgenic and nontransgenic lines showed no significant difference in growth index. However, while insect resistance was enhanced, effects related to the integration sites of the Bt gene occurred. A total of 15 insertion sites were detected among the six transgenic lines, and T-DNA preferentially inserted into AT-rich regions of the poplar genome. RNA sequencing and weighted gene co-expression network analysis were used to explore the effects of T-DNA insertion on the gene expression of poplar 107. As a result, the metabolic pathways most affected by the Bt gene were starch and sucrose metabolism and pentose and gluconate conversion. The expression of exogenous Bt had a greater impact than the insertion position or copy number on poplar 107 gene expression, and the Cry1Ac toxin protein also played a major role. This study provides theoretical support for the cultivation and management of poplar 107 new varieties, and provides reference for Poplar insect resistance breeding and its molecular response to Bt gene.
Haghighi, Tahereh MovahhedSaharkhiz, Mohammad Jamal
11页
查看更多>>摘要：Drought has become a global concern due to the climate-change. Here, the effects of Claroiedoglomus etunicatum inoculation (F-1) and without inoculation (F-0) and silicon nutrition (300 mg/L) (Si-1) and no silicon nutrition (Si0) were evaluated on morphophysiological and biochemical traits in Licorice (Glycyrrhiza glabra L.). The plants were exposed to drought stress (20%, 40%, 60%, 80%, and 100% field capacity (FC)). A significant trend (p -value < 0.05) was observed between Si0F1 (4.32 mu mol/g FW) and Si0F0 (3.76 mu mol/g FW) regarding the malondialdehyde content (MDA). The activities of superoxide dismutase (SOD) was significantly higher (0.91-0.94 U mg(-1) protein) (p -value < 0.05) in severe drought stress (20% FC) while peroxidase (POD) showed its maximum activity at 80% FC (48.86 U mg(-1) protein). Specifically, at 20% FC, there was a significant increase in catalase (CAT) activity (45.49 U mg(-1) protein) (p -value < 0.05). Minimum electrolyte leakage (EL), was observed at 40% FC in the fungi inoculated treatment (28.34%) and by Si application (26.28%). The fungi inoculation affected plant height positively and significantly (p -value < 0.05), as the height grew to 24.27 cm. The Si nutrition partially maintained plant performance, despite severe drought stress (20% and 40% FC). Taken together, the results indicated that microbial agent and mineral nutrition in the face of environmental stress, water deficit, improved enzymatic defense, morphophysiological features, quality and yield of G. glabra.
NSTL
Elsevier