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Invasive plants can grow rampantly and spread fast in large amount, which can be economically invoked for generating value-added products. In this study, lignocellulosic fiber was extracted from the leaf waste of a luxuriant invasive plant, Mikania micrantha Kunth-ex H.B.K. by mercerization process. After the alkaline treatment, the lignocellulosic biomass remained at 38.54% resulting from the large removal of extractive impurities. The lignocellulosic fraction in the mercerized leaf fiber was improved from 56.59% to 83.96%. The chemical composition analysis showed the cellulose fraction was increased by 11.17% while the hemicellulose and lignin fractions were found to be decreased by 4.89% and 6.28%, respectively. The FT-IR and TGA results further affirmed the change in chemical composition of the lignocellulosic fiber. Furthermore, an increase in cellulose fraction raised the fiber crystallinity index from 11.0% to 36.7%. The SEM study revealed that the surface morphology of lignocellulosic fiber changed from smooth surface into rough corrugated ridges, which affirmed the increase in crystallinity, resulting from the removal of wrapped cementing materials. In subsequent, the lignocellulosic fiber exhibited more pervious to water attack with an increase in moisture absorption from 119.22% to 410.19%. [ABSTRACT FROM AUTHOR]

Herein, an efficient epoxidation of 1-nonene is described. In a simple epoxidation system, commercially available Novozym 435, an immobilized Candida antarctica lipase B, and hydrogen peroxide (H₂O₂) were utilized to facilitate the in situ oxidation of phenylacetic acid to the corresponding peroxy acid which then reacted with 1-nonene to give 1-nonene oxide with high yield and selectivity. The aliphatic terminal alkene was epoxidised efficiently in chloroform to give an excellent yield (97%-99%) under the optimum reaction conditions, including temperature (35 °C), initial H₂O₂ concentration (30%), H₂O₂ amount (4.4 mmol), H₂O₂ addition rate (one step), acid amount (8.8 mmol), and stirring speed (250 rpm). Interestingly, the enzyme was stable under the single-step addition of H₂O₂ with a catalytic activity of 190.0 Ug-1. The entire epoxidation process was carried out within 12 h using a conventional water bath shaker. [ABSTRACT FROM AUTHOR]

Here, we describe an improved enzyme-facilitated epoxidation of 1-nonene using a conventional water bath shaker at ambient temperature. Enzymes were used to produce peroxy acids instantly from hydrogen peroxide (H2O2) and various perhydrolysis substrates. The peroxy acid generated was then utilised directly for in-situ oxidation of 1-nonene to 1-nonene oxide. Various parameters affecting the reaction were studied such as the nature of the peroxy acids, organic solvents, enzyme sources and enzyme concentrations. The highest conversion rate was achieved using phenylacetic acid as an oxygen carrier. 1-Nonene was converted most efficiently with 95% of the maximum yield by Novozym 435, an immobilised Candida antarctica lipase B, using dichloromethane as the reaction media. A minimum amount (16 mg, 1.4% w/w) of Novozym 435 was needed to maintain catalytic activity (160.0 Ug−1). In addition, a simple and rapid Gas chromatography mass spectroscopy selective ion monitoring (GC-MS SIM) method was developed using a HP-5ms column for determining 1-nonene oxide. The method was found to be linear in the range of 29.9 to 298.8 mg/L with R2 = 0.9981. [ABSTRACT FROM AUTHOR]

Solid acid catalyzed cracking of waste oil-derived fatty acids is an attractive route to hydrocarbon fuels. HZSM-5 is an effective acid catalyst for fatty acid cracking; however, its microporous nature is susceptible to rapid deactivation by coking. We report the synthesis and application of hierarchical HZSM-5 (h-HZSM-5) in which silanization of pre-crystallized zeolite seeds is employed to introduce mesoporosity during the aggregation of growing crystallites. The resulting h-HZSM-5 comprises a disordered array of fused 10–20 nm crystallites and mesopores with a mean diameter of 13 nm, which maintain the high surface area and acidity of a conventional HZSM-5. Mesopores increase the yield of diesel range hydrocarbons obtained from oleic acid deoxygenation from ~20% to 65%, attributed to improved acid site accessibility within the hierarchical network. [ABSTRACT FROM AUTHOR]

Here, we focused on a simple enzymatic epoxidation of alkenes using lipase and phenylacetic acid. The immobilised Candida antarctica lipase B, Novozym 435 was used to catalyse the formation of peroxy acid instantly from hydrogen peroxide (H2O2) and phenylacetic acid. The peroxy phenylacetic acid generated was then utilised directly for in situ oxidation of alkenes. A variety of alkenes were oxidised with this system, resulting in 75-99% yield of the respective epoxides. On the other hand, the phenylacetic acid was recovered from the reaction media and reused for more epoxidation. Interestingly, the waste phenylacetic acid had the ability to be reused for epoxidation of the 1-nonene to 1-nonene oxide, giving an excellent yield of 90%. [ABSTRACT FROM AUTHOR]

Plant extracts originated from an exotic species, Mikania micrantha Kunth ex H.B.K. have shown appreciable phytoinhibitory activities against a rice weed, Echinocloa colona (L.) Link. In spite of that, the glutinous extracts exhibit poor physicochemical properties preventing it from delivering efficiently and for ease of application. This research study aimed to formulate the leaf extract of M. micrantha with pre-emulsions and lignocellulosic coarse powder for the sake of ameliorated bioefficacy of the extract via nano-delivery system and improved product handling. Three pre-emulsions were developed using rapeseed oil methyl esters (ROME) and disparate bisurfactant mixtures including polyalkoxylated fatty alcohol (PAFA)-alkyl sulfonate (AS), PAFA-cocamidopropyl betaine (CB) and PAFA-alkyl polyglucosides (APG). The pre-emulsions were incorporated with leaf extracts containing the phenolic allelochemicals. The pre-emulsified extracts were loaded onto mercerized lignocellulose by solvent percolation and evaporation (SPE) technique produced the formulated water-dispersible coarse powders, WDP-F1, WDP-F2 and WDP-F3. A non-formulated extract was prepared into water-dispersible powder, WDP-EX for quality control. The results show greater water absorption by the formulated powders in prolonged duration of 7 days exerted the release of higher total amount of phenolic compounds (63.66–86.52%) than the phenolics amount released from the non-formulated powder (41.98%). Transmission electron microscopy (TEM) revealed the formulated extracts exhibited particles release in regular patterns from three dimensional networks and gigantic vesicles, unlike the non-formulated extract liberated uneven particles from disordered aggregates. The particles released from the formulated powders displayed low mean sizes (87.56–103.27 nm) in monodisperse range (PDI = 0.180–0.203). In opposition, non-formulated particles indicated larger mean size (423.93 nm) and polydisperse (PDI = 0.550). In the glasshouse study, the formulated powders promoted significantly higher inhibitions of germination, shoot height, fresh weight and dry weight of E. colona than non-formulated powder and non-treated weedy control. Moreover, the paddy seedling growth and grain yield treated with the formulated powders were statistically equivalent (p = 0.05) to treated with a commercial formulation, Satunil® and weed-free non-treated control. These valuable outcomes genuinely reflected the inspirational use of green water-dispersible coarse powder in the formulation of natural products in fostering the sustainable development of crop protection products. • Allelopathic leaf extract of Mikania micrantha in weed control of Echinochloa colona. • Pre-emulsion formulations of the leaf extract for physicochemical characterizations. • Lignocellulosic fiber incorporated pre-emulsion formulations into handy products. • Water-dispersible coarse powder formulations for sustained release of phenolics. • The powder formulations greatly suppressed E. colona while improved the rice yield. [ABSTRACT FROM AUTHOR]

Methyl methacrylate (MMA) has emerged as an essential industrial monomer. However, the toxic by-production and shortage supply of MMA in the global market has gained great attention. Herein, a one-step synthesis to produce MMA from isobutene via a direct oxidative esterification process has been demonstrated to curb the aforementioned downsides. Thermodynamic analysis via Gibbs free energy minimization method proved the feasibility of this route via the equilibrium constant. Despite tert-butanol and isobutane showed higher equilibrium constant than isobutene, they should be avoided. Isobutane is highly flammable while the precursor of tert-butanol is exorbitant. Thus, isobutene was selected for the equilibrium compositions screening. Isobutene conversion was 90% and 15% MMA yield at 700 °C and IBN: O2: MeOH ratio with 1:7:1. This route is mainly limited by the generation of side reactions from the reaction of CH3OH and O2. By varying the feedstock ratio at 1:2:1, the MMA yield increased to ~25%. [ABSTRACT FROM AUTHOR]

Palm fatty acid distillate (PFAD) is considered as an inedible and renewable feedstock for the production of green diesel. In the current study, green diesel was successfully synthesised via catalytic deoxygenation of PFAD in an environment free of H 2 using a mesoporous activated carbon (AC) supported CoMo catalyst with various molybdenum (Mo) concentrations (5–20 wt%). Based on the study results, bimetallic catalyst Co 10 Mo 10 /AC formulation exhibited excellent catalytic performance with 92% hydrocarbon components (C 8 -C 20) yield and 89% selectivity for n -(C 15 + C 17) with a total acid number of 24 mg KOH mg−1. Based on a comparison study with various supports (AC, γ-Al 2 O 3, TiO 2), the AC-supported CoMo catalyst showed higher deoxygenation activity than both Co 10 Mo 10 /γ-Al 2 O 3 and Co 10 Mo 10 /TiO 2 owing to the super acid-base sites as a result of synergism between the CoMo and AC support. The Co 10 Mo 10 /AC catalyst demonstrated excellent stability during the study as it maintained the hydrocarbon components yield and selectivity of n -(C 15 + C 17) >80% until the sixth run. Unlabelled Image • The CoMo/ AC bimetallic catalyst successfully converted PFAD to green diesel under N 2 ambient. • The decarboxylation is the major pathway in the deoxygenation reaction under N 2 ambient. • The deoxygenated liquid product mainly composed of saturated (C 15 + C 17). • The catalytic activity of AC support was higher than (Al2O3 & TiO2) due to possessing super acid-base characteristics. • The CoMo/ AC catalyst demonstrated good thermal stability and reusability. [ABSTRACT FROM AUTHOR]

Here, we focused on a simple enzymatic epoxidation of alkenes using lipase and phenylacetic acid. The immobilised Candida antarctica lipase B, Novozym 435 was used to catalyse the formation of peroxy acid instantly from hydrogen peroxide (H2O2) and phenylacetic acid. The peroxy phenylacetic acid generated was then utilised directly for in situ oxidation of alkenes. A variety of alkenes were oxidised with this system, resulting in 75-99% yield of the respective epoxides. On the other hand, the phenylacetic acid was recovered from the reaction media and reused for more epoxidation. Interestingly, the waste phenylacetic acid had the ability to be reused for epoxidation of the 1-nonene to 1-nonene oxide, giving an excellent yield of 90%.