查看更多>>摘要：? 2022 Elsevier B.V.Malaria is one of the major global health concerns that affect millions of people worldwide annually, especially people residing in the developing countries. The previously implemented measures to control and cure malaria are now being hampered due to the progression of multiple drug-resistance in the malaria-causing Plasmodium species. Artemisinin-based Combination Therapies (ACTs) are the most effective treatment available to medicate malaria, as recommended by World Health Organization (WHO). Artemisia annua L. (sweet wormwood) is a member of the family Asteraceae and is classified under the genus Artemisia. A. annua produces artemisinin (a sesquiterpene lactone) which has remarkable efficacy against multi-drug resistant malaria-causing parasite (Plasmodium species) and is a major component of ACTs. Due to low artemisinin content in naturally growing plants and low availability against high demand, attempts have been made during the past to increase the artemisinin content by way of selective breeding, micropropagation, pathway engineering, and genetic manipulations. Due to the limited progress, the implementation of novel strategies and advanced scientific methodologies are required to fill the gap between the global demand and supply of artemisinin and its derivatives. The enhancement in total phytochemical content in A. annua, especially artemisinin, has both commercial as well as medicinal significance for global humankind. This review focuses on different aspects of artemisinin production, including the efforts that have been made towards its enhancement in the natural population, and other socio-economic factors associated with the demand and supply of medicinally useful artemisinin and its derivatives.
查看更多>>摘要：? 2022 Elsevier B.V.Pogostemon cablin, commonly known as Patchouli (family-Lamiaceae) is a perennial aromatic herb with many medicinal properties and has immense use in different pharmaceutical industries. In this study genetic variability and association studies were performed for 200 M4 population derived from chemical and physical mutagenic agents. The trial was planted in Randomized Block Design and eleven morphological and quality characters were taken for the study during the year 2020. Analysis of variance (ANOVA) showed high phenotypic and genotypic coefficient of variation (PCV, GCV) for fresh herbage yield per plant, number of monopodia and number of sympodia. High heritability with high genetic advance was observed for the characters, like-length of sympodia (86.703, 28.942), plant height (86.001, 27.439). Correlation study revealed that length of sympodia has significant positive correlation with dry weight of herbage yield/plant, while essential oil yield percentage showed significant negative correlation with fresh herbage yield and dry herbage yield per plant. Patchouli alcohol percentage was also found to be significant and negatively correlated with fresh herbage yield and dry herbage yield per plant. Path coefficient study showed fresh herbage yield/plant to have highest positive direct effect (0.628) on dry weight of herbage yield/plant, while length of monopodia showed highest positive direct effect (0.120) on essential oil percentage. Genetic divergence study partitioned the genotypes into eight clusters, thereby showing great variability among them for the studied traits. So, for increasing essential oil quality characters like- number of sympodia and number of monopodia should be considered and for increasing herbage yield quality, length of sympodia should be taken as selection criteria.
查看更多>>摘要：? 2022 Elsevier B.V.The acquisition of transgenic materials relies on an efficient genetic transformation system, in which WUSCHEL-related homeobox genes play imperative roles in enhancing somatic embryogenesis potential. In our study, we isolated and characterized the cotton (Gossypium hirsutum L) homologues of Arabidopsis WOX11 and WOX12, namely GhWOX11_At, GhWOX11_Dt, GhWOX12_Dt and GhWOX12_At. Domain analysis indicated that the putative GhWOX11 and GhWOX12 proteins contain a highly conserved DNA-binding HOX domain or ACR domain. We have also demonstrated that callus initiation and adventitious root formation are simultaneously regulated by GhWOX11/12 genes. The asymmetric distribution of auxin leads to the differential expression of GhWOX11 and GhWOX12, which controls the formation of callus and presents a polar distribution at the ends of hypocotyl. Furthermore, overexpression of GhWOX11/12 significantly promotes the formation of callus and the fate transition from callus cell to pluripotent cell in G. hirsutum. On the other hand, expression of the chimeric GhWOX11/12 repressor in cotton callus inhibited embryogenic callus formation. Overexpression of GhWOX11 also promoted the formations of green callus, adventitious roots and adventitious shoots in Arabidopsis, corroborating its conserved functional role in inducing plant somatic embryogenesis and root development. Our results show that GhWOX11 and GhWOX12 genes play an important role in the process of cell fate transition in the early stage of somatic embryogenesis, providing a new perspective for the optimization of plant transformation systems.
查看更多>>摘要：? 2022 Elsevier B.V.Hemp bast fibers were degummed using combined microwave energy (MWE) and deep eutectic solvent (DES) to generate pure hemp cellulose fibers for potential textile applications. The properties of the degummed fibers were investigated and compared with those of the alkali-treated fibers using several analytical techniques. Results revealed that hemp fiber surface underwent dramatic structural disruption during the pretreatment, due to the removal of “gummy” compounds (i.e., pectin, oil, wax, etc.), lignin, and amorphous cellulose. The treated fibers had much enhanced thermal stability due to the removal of the gummy materials. The reduced enthalpy (171.34 J/g) of MWE-DES treated fibers at 1:20 fiber-DES ratio as compared to that of raw hemp fibers (272.09 J/g) also confirmed the higher thermal stability of MWE-DES treated fibers. Chemical composition analysis showed that the holocellulose content in the treated fiber samples at 1:20 fiber-DES ratio increased to 98.63% which was comparable with the holocellulose content (98.87%) of the alkali-treated fibers. The Ultraviolet (UV) protection factor (UPF) of MWE-DES treated fibers at 1:10 and 1:20 fiber-DES ratio was, respectively, 118.11 and 114.19, meeting the requirement of UV resistant textile fibers. The study demonstrates a potentially effective, less time-consuming, and environmentally sustainable protocol for manufacturing purified hemp cellulose fibers using combined MWE-DES treatment.
查看更多>>摘要：? 2022 Elsevier B.V.Removing phenolic compounds from water resources is urgent as they have seriously damaged aquatic ecological equilibrium. In this study, divanillin-based porous organic polymers (DPP) and 2,5-furandicarboxaldehyde-based porous organic polymers (FPP) were prepared from sustainable lignocellulose-derivatized monomers using a one-step synthetic method. The characterization highlighted the large Brunauer–Emmett–Teller (BET) surface area (SBET 513.9 and 772.8 m2?g?1), mainly mesoporous property (3.4 and 6.5 nm) and high nitrogen content (over 25%) of the obtained DPP and FPP, which rendered them high adsorption affinity toward phenolic pollutants. Specifically, DPP and FPP exhibited the highest adsorption capacity for p-nitrophenol (PNP) (254.2 and 339.4 mg?g?1) calculated by the Langmuir isotherm model. The porous networks of DPP and FPP enabled fast sorption kinetics for PNP with adsorption equilibrium times of only 8 and 4 min, respectively. Thermodynamic investigation revealed adsorption followed spontaneous and exothermic chemisorption processes. The interaction between the PNP and DPP/FPP mainly involved the synergism of hydrogen-bonding interactions, electrostatic force, and π-π stacking interactions. Furthermore, DPP and FPP exhibited outstanding durability and retained over 78.9% and 81.9% removal efficiency for PNP after ten cycles. Therefore, these biobased materials with high adsorption capacity and rapid adsorption rate show promising application in wastewater treatment.
查看更多>>摘要：? 2022 Elsevier B.V.Oregano essential oil (OEO) has great antioxidant and antifungal potential as a natural bioinhibitor, which is limited by its volatility and instability. In this study, OEO was loaded onto mesoporous nanosilica (MNS) to prolong the efficacy of biological inhibitors and then oxidized esterified tapioca starch (OETS) was used as a film-forming matrix to develop bio-nanocomposites for packaging by the casting method. Transmission electron microscopy (TEM), fourier transform infrared (FT-IR), and thermogravimetric analysis (TGA) were used to analyze the loading effect of nanoparticles. Then, the microstructure, physical, barrier, antioxidant and antifungal properties of the active films containing OEO–MNS were evaluated and compared with those of the OETS-based film. The results showed that the presence of OEO–MNS endowed the film with antioxidant, antifungal, and ultraviolet-blocking properties, as well as improved tensile strength (TS) and water resistance. Specifically, the best performance was obtained for the OETS-based film containing 0.9% OEO–MNS with a uniform nanoparticle distribution. Meanwhile, the TS of the active films reached up to 6.97 MPa, which was about 236% higher than that of the pure OETS-based films. In addition, the film incorporating 1.5% OEO–MNS had the highest antioxidant capacity and excellent antifungal activity. The prepared multifunctional nanocomposite films containing essential oil have promising applications in the field of active packaging.
查看更多>>摘要：? 2022 Elsevier B.V.Functionalized microcrystalline cellulose (MCC) and its composites have a wide range of applications. In this research, bio-based phytic acid (PA) rich in phosphorus and condensed tannins (CT) were incorporated into MCC, and a product PA/CT/MCC with excellent flame retardant and cationic dye adsorption properties was prepared. The FT-IR and ICP-MS analyses confirmed the phosphorylation of MCC. The thermal stability, charring ability, heat release capability, and combustibility of PA/CT/MCC were investigated. PA/CT/MCC was susceptible to degradation and charring at low temperature primarily resulting from the pyrolysis products of PA, and yielded char layers at high temperature. Furthermore, PA/CT/MCC had a very low heat release capability in the microscale combustion, and displayed excellent flame retardancy in the vertical combustion, thereby being a potential FR material. Additionally, PA/CT/MCC exhibited a strong capability of adsorbing cationic dye from water, thereby being a potential adsorbent for removing cationic dye. The adsorption of cationic dye on PA/CT/MCC followed the pseudo-second-order kinetic model and the Langmuir–Nernst dual isotherm model. The Langmuir adsorption played a major role in total adsorption. This research suggests the novel approaches of constructing flame retardant and adsorptive MCC materials, which have potential application prospects in the fire protection and water treatment fields, respectively.
查看更多>>摘要：? 2022 Elsevier B.V.Deep eutectic solvents (DESs) composed by carboxylic acids and quaternary ammonium salts are potential candidate for lignocellulose dissolution and pretreatment. To both explore the most efficient DESs for lignocellulose dissolution and pretreatment as well as unveil the process mechanism, DESs composed by carboxylic acids as the hydrogen bond donors (HBDs) and quaternary ammonium salts as the hydrogen bond acceptors (HBAs) were prepared and further applied for kraft lignin (KL) dissolution as well as poplar and pine pretreatment. We found DES composed by lactic acid (LA) and allyltrimethylammonium chloride (ATMAC) with mole ratio of 2:1 is high-efficient for the dissolution of KL. In addition, 70% poplar lignin and 82% pine lignin could be removed at 120 ℃ for 6 h with a solid-to-liquid ratio of 1:10. Furthermore, the -OH and -COOH groups in HBDs [dbnd] of DESs provided active protons to cleave ether bonds and part of carbon-carbon bonds during lignin dissolution and extraction. Additionally, the KL solubility and the Kamlet-Taft (K-T) parameters (α and π * ) of the DESs showed good positive correlation. These findings give a deep insight into the dissolution mechanism of KL and pretreatment of lignocellulose, which is helpful for designing robust DESs for dissolution and pretreatment of lignocellulose.
查看更多>>摘要：? 2022 Elsevier B.V.Antibacterial textiles that repel external liquids while synchronously transport internal sweat to keep comfort moisture balance are desirable. However, very limited success has been achieved to construct such textiles. Herein, a facile approach to create durable antibacterial cotton fabric with skin-like wet management was proposed. The first step involved several minutes (< 5) dip-coating subsequently with PA and Cu2+, which afforded Cu enriched surfaces endowing highly efficient (99.95% in 2 h for E. coli, 99.99% in 2 h for S. aureus) and durable antibacterial activity (> 99.95% after 50 times washing treatment). The following step further paved a way of skin-like wet management by the construction of dotted wetting gradient on superhydrophobic background via transient exposure to a vapor mixture of methylchlorosilanes and successive patterned plasma etching. The liquid could only be transferred in the direction of the wetting gradient and was stopped when the fabric was faced against it, featuring synchronous antifouling and unidirectional water transmission so as to avoid wet clicking of the fabric with high air permeability even in a wet environment. This study opens a way for developing advanced fabrics which voluntarily release human sweat and meanwhile restrain microbial development obviating bacterial infection.
查看更多>>摘要：? 2022 Elsevier B.V.The exploration of plant bioactive components for plant protection is significant for sustainable development of agriculture. Although the essential oil of Melaleuca alternifolia Maiden & Betche Cheel has been widely applied in many fields, its non-volatile active components are not fully utilized in agriculture. This study found that nonvolatile components of M. alternifolia possessed fungicidal activity against Rhizoctonia solani Kühn. The n-butanol extract of M. alternifolia mixed with borneol at a ratio of 5:1 enables good synergism in terms of antifungal activity. Importantly, the fungicidal activity against R. solani can be further significantly improved by microemulsification. The 10% microemulsion (ME) possessed significant preventive and curative efficacy against R. solani in rice plants with control efficacy of 85.29% and 76.87% at 300 mg/L, respectively. They are comparable to the control efficacy of 8% validamycin A aqueous at 300 mg/L. The 10% ME could also suppress the formation of sclerotia of R. solani even at a low concentration of 50 mg/L. Primary study on the mechanism of action indicated that 10% ME destroyed the cell membrane and mitochondria, triggered the release of cellular contents, produced reactive oxygen species (ROS) and reduced the number of cell nuclei in R. solani mycelia. This study demonstrates that the nonvolatile components of plants are valuable resources for the development of plant-source green formulations for the control of phytopathogenic bacteria and fungi.
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