Application of Cocultures of Fungal Mycelium during Solid-State Fermentation of Canola Meal for Potential Feed Application

In this study, the mono-, bi-, and tri-cultivation of Aureobasidium pullulans, Neurospora crassa, and Trichoderma reesei in solid-state fermentation were applied to improve the nutritional values of hexane extracted canola meal (HECM) along with the reduction of antinutritional factors for animal feed applications. Static fermentation trials of 50% moisture content HECM were conducted in 500 mL Erlenmeyer flasks for 168 hours at 30 °C. The results showed that fungal cultivation had positive effects on the level of protein, fiber, and, glucosinolates (GLS). Monoculture of N. crassa exhibited the highest protein level of 49%. The combination of A. pullulans and N. crassa provided the highest reduction of crude fiber, acid detergent fiber and neutral detergent fiber by 21.9%, 1.7%, and 9.1%, respectively. Bi-culture of A. pullulans and T. reesei resulted in the best GLS reduction by 81.3% (0.3 vs. 1.6 μM g⁻¹ GLS of uninoculated control). These results indicate that each fungal strain possesses different enzymatic ability and selectively can work with other fungi in synergistic relationship for better fungal conversion of canola meal.     

Production of Canolol from Canola Meal Phenolics via Hydrolysis and Microwave-Induced Decarboxylation

A potent antioxidant, anti-inflammatory and anti-mutagenic agent; 4-vinyl-2,6-dimethoxyphenol (canolol) was obtained from canola meal in a significant yield via alkaline (NaOH)/enzymatic (ferulic acid esterase) hydrolysis followed by microwave-assisted decarboxylation. The hydrolysis was carried out either through using canola meal directly as a substrate or by using the 70 % aqueous methanolic extract filtrates. The hydrolyzed extracts underwent RP-HPLC analysis which showed that 81.0 and 94.8 % of the total phenolics were hydrolyzed to sinapic acid after the alkaline hydrolysis of the meal and the methanolic extracts, respectively. The enzymatic hydrolysis showed lower conversion rates (49.5 and 58.3 %). The hydrolyzed extracts were consequently decarboxylated using 8-diazabicyclo[5.4.0]undec-7-ene under microwave irradiation at different conditions. The HPLC profiling of decarboxylated extracts showed that using microwave at 300 W of microwave power for 12 min brought the highest sinapic acid conversion to canolol (58.3 %) yielding 4.2 mg canolol from each gram of canola meal suggesting that the process could be commercially economical.     

Submerged vs. Solid-State Conversion of Soybean Meal into a High Protein Feed Using Aureobasidium pullulans

The goal of this study was to assess the performance of Aureobasidium pullulans in converting soybean meal (SBM) into high protein feed using the submerged and solid-state processes. High solid loading rates (SLR) were evaluated for each process, i.e., 10–25% for submerged and 35–70% for static solid-state fermentation. During the submerged fermentation, 10% SLR was considered the best performer due to the high amount of cell density, low residual carbohydrates, and high protein titers, while 40% SLR resulted in the high protein yields and low residual carbohydrates during the static solid-state fermentation. The solid-state fermentation was conducted in a 14-L paddle-type reactor at 50% SLR, and periodic mixing resulted in a protein titer of ~58% at 72 hours of fermentation. Overall, results showed the feasibility of scaling up these processes in converting SBM to a high protein feed ingredient for animal diet.     

Identification of a TBHQ-Interfering Peak in Crude Canola Oil Using AOCS Official Method Ce 6-86 and its Chromatographic Resolution

AOCS Official Method Ce 6-86 “Antioxidants, Liquid Chromatographic Method” was originally developed to confirm the correct antioxidant was added at the specified concentration to refined oils. Today, this method is increasingly utilized to validate that antioxidants are absent from oil products. False positive results can have a significant impact on the ability to sell products in specific markets and can impart additional business expenditures for conclusive secondary analyses. In the current work, quantification of tert-butylhydroquinone (TBHQ) in crude canola/rapeseed oil using liquid chromatography (LC) with ultraviolet (UV) detection was compromised by an interfering peak. Analyses using liquid chromatography-mass spectrometry (GC–MS) and high-resolution accurate mass LC–MS identified the interferent as 2,6-dimethoxy-4-vinylphenol (canolol), an endogenous compound present in crude canola/rapeseed oil. Resolution of canolol and TBHQ using LC-UV can be achieved via minor modification of the chromatographic conditions.     

Degradation of Phytic Acid and Soy Protein in Soy Meal via Co-fermentation of Aspergillus oryzae and Aspergillus ficuum

The usage of soy meal (SM) as a protein source for young monogastric animals is limited by the presence of antinutritional factors. To address this problem, fermentation was applied to simultaneously degrade phytic acid and soy protein in SM. Aspergillusoryzae (ATCC 9362) and Aspergillusficuum (ATCC 66876), sources of protease and thermostable phytase, respectively, were co‐fermented using a two‐stage temperature protocol: 36.5 °C (0–28 h), then 50 °C (28–40 h). The two‐stage co‐fermentation approach achieved a 17 % increase of phytic acid degradation compared to A. oryzae fermentation and 72 % increase in protein degree of hydrolysis (DH) compared to A. ficuum fermentation. The two‐stage temperature fermentation produced a 27 % increase in phytic acid degradation and 90 % increase in DH compared to a single‐stage fermentation. The fermented SM with reduced levels of antinutritional factors would serve as high quality feedstuff.     

Conversion Process of Strontium–Titanium Bimetallic Methoxyethoxide Precursor into SrTiO3 via Hydrolysis/Calcination

The conversion of a Sr–Ti bimetallic methoxyethoxide precursor into SrTiO₃ via hydrolysis and/or calcination was investigated. Hydrolysis with various water/metal molar ratios ( r _H; r _H= 0.5, 2, 4, 6, 8, 10) in tetrahydrofuran at reflux resulted in a decrease in the amount of the methoxyethoxyl groups, and the hydrolyzed products were soluble with r _H≤ 2. At r _H≥ 8, SrTiO₃ was crystallized without calcination. Both the hydrolyzed and unhydrolyzed precursors ( r _H= 0, 0.5, 2) were calcined in dry air at 550°–800°C. SrTiO₃ was crystallized on calcination at ≥550°C from amorphous materials with a considerable loss of carbon, which was present as both chars and carbonate ions.     

Process synthesis and optimization of a sustainable integrated biorefinery via fuzzy optimization

Over the last decade, utilization of biomasses is highly encouraged to conserve scarce resources, reduce dependency on energy imports as well as protect the environment. Integrated biorefinery emerged as noteworthy concept to integrate several conversion technologies to have more flexibility in product generation with energy self‐sustained and reduce the overall cost of the process. Integrated biorefinery is a processing facility that converts biomass feedstocks into a wide range of value added products via multiple technologies. In this work, a systematic approach for the synthesis and optimization of a sustainable integrated biorefinery which considers economic, environmental, inherent safety, and inherent occupational health performances is presented. Fuzzy optimization approach is adapted to solve four parameters simultaneously as they are often conflicting in process synthesis and optimization of an integrated biorefinery. An integrated palm oil‐based biorefinery case study is solved to demonstrate the proposed approach. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4212–4227, 2013     

Conversion of a polysilazane-modified cellulose-based paper into a C/SiFe(N,C)O ceramic paper via thermal ammonolysis

Cellulose-based paper samples were surface-modified by a polymeric single-source precursor prepared from perhydropolysilazane (PHPS) and iron(III)acetylacetonate (Fe(acac)₃) and ammonolyzed at 500°C, 700°C, 900°C, and 1000°C, leading to C/SiFe(N,C)O-based ceramic papers with in situ-generated hierarchical micro/nano-morphology. As reference, cellulose-free samples were prepared under the same conditions. Upon thermal treatment, the microstructure evolutions of the resulting ceramic paper and the reference sample were comparatively investigated. Scanning electron microscopy (SEM) showed that for all temperatures, the ceramic papers exhibit the same morphology as the template, however, with noticeable shrinkage and curling, particularly evident at higher temperatures. X-ray diffraction (XRD) measurements of the reference samples and the ceramic papers showed a similar crystallization behavior and phase evolution in both materials. In the ceramic paper, the crystallization process seems to occur at a later time. The results provide a comprehensive understanding of the investigated C/SiFe(N,C)O-based ceramic system. It was shown that use of the cellulose-based paper template has the benefit of retaining the microstructure and furthermore, apart from transforming the cellulose fibers into turbostratic carbon, does not change the phase evolution during the polymer-to-ceramic transformation, allowing at the same time the manufacturing of novel morphologically complex parts by a convenient one-pot synthesis approach.     

Conversion of polyester into heat‐resistant polyamide by reacting with aromatic diamine compound II. Semibatch reaction by nitrogen gas sweeping process

The conversion of poly(ethylene terephthalate) (PET) into heat‐resistant polyamide was carried out in the solid state polycondensation by applying a nitrogen gas sweeping process. The reaction product obtained by the catalyzed and uncatalyzed batch reaction with the specified reaction condition was used as the starting material in the semibatch reaction process. Nitrogen gas was introduced into the reactor to remove a volatile reaction byproduct from the reaction mixture. Effect of the semibatch reaction variables such as temperature, time, and nitrogen gas sweeping rate on the extent of reaction and the heat‐resistant property of polyamide obtained was investigated. A comparison of the extent of reaction in the semibatch reaction process was made between the catalyzed starting material and the uncatalyzed one. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2223–2232, 2004     

A two-dimensional Monte Carlo model for pore densification in a bi-crystal via grain boundary diffusion: Effect of diffusion rate,initial pore distance,temperature, boundary energy and number of pores

A two-dimensional Monte Carlo (MC) model is introduced for simulating the evolution of the pore on a bi-crystal grain boundary via grain boundary diffusion. Simulated pore shrinkage kinetics is found to be consistent with previously reported results over variable grain boundary diffusion rates and initial pore distances while the essential characteristics of the microstructural evolution are simultaneously realized. The influence on the pore densification kinetics of grain boundary motion, boundary energy ratio, simulation temperature and pore interactions in an array is found such that pore shrinkage rate increases as the grain boundary motion, the simulation temperature and the grain boundary energy increase. The interactions of the pores are found to hinder the pore densification. The body of results signify that the more elongated the pore shape and the shaper the pore tip region are favored for the faster pore shrinkage kinetics during the simulated densification process via grain boundary diffusion.     

Conversion of carbohydrates into 5‐hydroxymethylfurfural in a green reaction system of CO2‐water‐isopropanol

In this work, a green reaction system of CO₂‐water‐isopropanol was developed for 5‐hydroxymethylfurfural (HMF) production. The conversion of fructose in a CO₂‐water system was first investigated, and the results showed this system could promote the formation of HMF compared to a pure water system. Then, isopropanol was introduced into the CO₂‐water system and the HMF formation became better because the solvent effect of isopropanol increased the tautomeric composition of fructofuranose, which was easy to form HMF. The existence of isopropanol was found to greatly suppress secondary reactions where HMF was converted to levulinic acid and insoluble humin. Meanwhile, the effects of reaction parameters on the conversion of fructose to HMF in the CO₂‐water‐isopropanol system were analyzed, and a high HMF yield of 67.14% was obtained. Finally, to further illustrate the merits of CO₂‐water‐isopropanol system, productions of HMF from other carbohydrates were tested and satisfactory yields were achieved. © 2016 American Institute of Chemical Engineers AIChE J, 63: 257–265, 2017     

Fabrication of Ultrahigh‐Strength Polybenzimidazole Fibers via a Novel and Green Integrated Liquid Crystal Spinning Process

Herein, the first example of ultrahigh‐strength polybenzimidazole (PBI) fibers using a PBI solution in liquid crystal state is reported via a novel and green integrated spinning technology. Microwave‐assisted polycondensation is utilized to synthesize the polybenzimidazole/polyphosphoric acid liquid crystal spinning solution and pure water is employed as the coagulating and washing bath to afford a green fabrication process. The green integrated spinning technology is eco‐friendly, cheap, and conducive for the large‐scale production of PBI fibers. The as‐prepared PBI fibers display superb flame retardancy, and the outstanding thermal stability of PBI fiber enables it to preserve structural integrity at temperatures as high as 600 °C. More significantly, it prepared the ultrahigh‐strength of PBI fiber up to 0.91 GPa, which is two times than that of the reported PBI fibers, marking a significant breakthrough for the high‐performance PBI fibers.     

One‐Pot Conversion of L‐Threonine into L‐Homoalanine: Biocatalytic Production of an Unnatural Amino Acid from a Natural One

A novel biocatalytic process for production of L ‐homoalanine from L ‐threonine has been developed using coupled enzyme reactions consisting of a threonine deaminase (TD) and an ω‐transaminase (ω‐TA). TD catalyzes the dehydration/deamination of L ‐threonine, leading to the generation of 2‐oxobutyrate which is asymmetrically converted to L ‐homoalanine via transamination with benzylamine executed by ω‐TA. To make up the coupled reaction system, we cloned and overexpressed a TD from Escherichia coli and an (S)‐specific ω‐TA from Paracoccus denitrificans. In the coupled reactions, L ‐threonine serves as a precursor of 2‐oxobutyrate for the ω‐TA reaction, eliminating the need for employing the expensive oxo acid as a starting reactant. In contrast to α‐transaminase reactions in which use of amino acids as an exclusive amino donor limits complete conversion, amines are exploited in the ω‐TA reaction and thus maximum conversion could reach 100%. The ω‐TA‐only reaction with 10 mM 2‐oxobutyrate and 20 mM benzylamine resulted in 94% yield of optically pure L ‐homoalanine (ee>99%). However, the ω‐TA‐only reaction did not produce any detectable amount of L ‐homoalanine from 10 mM L ‐threonine and 20 mM benzylamine, whereas the ω‐TA reaction coupled with TD led to 91% conversion of L ‐threonine to L ‐homoalanine.     

Preparation and Mechanical Properties of Long Glass Fiber Reinforced PA6 Composites Prepared by a Novel Process

Summary: Long glass fiber reinforced PA6 (LGF/PA6) prepregs were prepared by impregnating PA6 oligomer melt into reinforcing glass fiber followed by subsequent solid‐state polymerization (SSP) to obtain LGF/PA6 composite pellets. A conventional injection‐molding machine suitable for short glass fiber reinforced composites was applied to the processing of the prepared composites, which reduced the fiber length in the final products. Mechanical properties, thermal property, and fiber length distribution of injection molding bars were investigated. Scanning electron microscopy (SEM) was used to observe the impact fracture surfaces and the surfaces of glass fiber after the SSP. It was found that the LGF/PA6 composites were of favorable mechanical properties, especially the impact strength, although the average length of glass fiber was rather short. By this novel process, the content of glass fiber in composite could be high up to 60 wt.‐% and the maximum level of heat distortion temperature (HDT) was close to the melting temperature of PA6. SEM images indicated the favorable interfacial properties between the glass fiber and matrix. The glass fiber surfaces were further observed by SEM after removing the matrix PA6 with a solvent, the results showed that PA6 macromolecules were grafted onto the surface. Furthermore, the grafting amount of PA6 was increased with SSP time.

SEM images of impact fracture surfaces of LGF/PA6 composites (left) and of glass fiber surfaces after removing PA6 with 5 h SSP (right).     

Facile and Selective Synthesis of Imidazobenzimidazoles via a Copper‐Catalysed Domino Addition/Cycloisomerisation/ Coupling Process

A copper(I)‐catalysed domino transformation for the synthesis of tricyclic imidazobenzimidazole derivatives was developed. Using readily available primary propargylic amines and o‐haloarylcarbodiimides as the starting materials, a variety of substituted benzo[d]imidazo[1,2‐a]imidazoles was efficiently and selectively assembled. Further investigations indicated that the domino reaction was likely the result of a novel addition/cycloisomerisation/coupling process.

     

Novel and Mild Route to Phthalocyanines and 3‐Iminoisoindolin‐1‐ones via N,N‐Diethylhydroxylamine‐Promoted Conversion of Phthalonitriles and a Dramatic Solvent‐Dependence of the Reaction

Refluxing a mixture of phthalonitrile C₆R¹R²R³R⁴(CN)₂ 1 (R¹–R⁴=H), or its substituted derivatives 2 (R¹, R³, R⁴=H, R²=Me), or 3 (R¹, R⁴=H, R², R³=Cl) (1 equiv.) and N,N‐diethylhydroxylamine, Et₂NOH, (4 equivs.) in methanol for 4 h results ( Route A ) in precipitation of the symmetrical ( 6 and 8 ) and an isomeric mixture of unsymmetrical ( 7 ) phthalocyanines, isolated in good (55–65 %) yields. The reaction of phthalonitriles 1 , 2 , or 4 (R¹, R³, R⁴=H, R²=NO₂) (4 equivs.) with Et₂NOH (8 equivs.) in the presence of a metal salt MCl₂ (M=Zn, Cd, Co, Ni) (1 equiv.) in n‐BuOH or without solvent results in the formation of metallated phthalocyanine species ( 9 – 17 ). Upon refluxing in freshly distilled dry chloroform, phthalonitrile 1 or its substituted analogues 2 , 3 or 5 (R¹–R⁴=F) (1 equiv.) react with N,N‐diethylhydroxylamine (2 equivs.) affording 3‐iminoisoindolin‐1‐ones 18 – 21 ( Route B ) isolated in good yields (55–80 %). All the prepared compounds were characterized with C, H, and N elemental analyses, ESI‐MS, IR, and compounds 18 – 21 also by 1D (¹H, ¹³C{¹H}), and 2D (¹H,¹⁵N‐HMBC and ¹H,¹³C‐HMQC, ¹H,¹³C‐HMBC) NMR spectroscopy.