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In an effort to provide a theoretical basis and data reference for the efficient processing and utilization of peanuts, changes in the moisture content, browning degree, particle texture parameters, water state and distribution, and protein denaturation degree of peanuts before and after microwave pretreatment were investigated, as well as the effect of microwave pretreatment on the yield of screw-pressed peanut oil. The results were compared with those obtained using vacuum oven drying. Meanwhile, for each pretreatment, the Pearson correlation between oil yield and moisture content, browning index (BI), particle texture parameters, water state, and protein denaturation degree was determined. The results showed that after microwave treatment for 7 min at 900 W or vacuum oven treatment at 85 ℃ for 89 min, the moisture content of peanuts decreased from 5.25% to 2.27%, with the highest oil yields of 45.85% and 45.76% being obtained, respectively. Under these conditions, the shear stress formed between peanuts and the oil press was moderate, peanuts were fully squeezed and deformed, with a large amount of oil flowing out, and peanuts had the best plasticity, the most ideal moisture state and a moderate degree of protein denaturation, so that not only a large amount of oil flowed out, but also peanuts were not easily broken, thus not affecting the formation of peanut cake.

In this study, the flavor components of double-low fragrant rapeseed oils (cv. “Zhongyouza 19”) from nine different planting areas were qualitatively and quantitatively analyzed by headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry coupled with olfactometry (GC-MS-O). The results showed that a total of 63 aroma-active compounds were identified using two columns (polar and non-polar) at a total concentration of 222.0 to 468.9 mg/kg. The total concentration of aroma compounds was highest in the Hunan sample and lowest in the Jiangxi sample. Out of the identified flavor substances, 38 had odor activity value (OAV) greater than 10. The results of partial least squares-discriminant analysis (PLS-DA) and sensory evaluation showed that 2-methylpyrazine, 2,3,5-trimethylpyrazine, and 2-methyl-3,5-diethylpyrazine were the main contributors to roasted aroma notes, 3-butenylisothiocyanate provided spicy notes, and 5-hexenenitrile and 4-methylthionitrile led to green notes. Based on variable important in the projection (VIP) values, nine key differential substances were selected, namely, methanthiol, 2-methylpyrazine, 2,3-diethyl-5-methylpyrazine, dimethyl disulfide, 5-methylthiopentonitrile, 5-hexenenitrile, (E,Z)-2,4-pentadienonitrile, hexanal and dimethyl trisulfide. They could be considered as potential flavor markers for the discrimination of double-low fragrant rapeseed oils from different planting areas. This research can provide a theoretical guide for the screening of raw materials for fragrant rapeseed oils.

Summary: There was an extensive interest in food‐grade Pickering emulsions formulated by natural stabilisers owing to the gradual growing demand for pursuing green‐label products. Based on this, the desalted duck egg white nanogels (DEWN) combined with κ‐carrageenan (CAR) (CAR/DEWN) were used as stabilisers to prepare environment‐friendly Pickering emulsions. The DEWN and CAR/DEWN as well as the particles‐stabilised emulsions were all characterised. Compared with the DEWN‐ and CAR‐stabilised emulsions, Pickering emulsions based on CAR/DEWN were investigated to illustrate the long‐term stability according to the results of visual appearance, static multiple light scattering and centrifugation experiments. In addition, CAR/DEWN could prepare stable high internal phase emulsions, which may give a new perspective for nutraceutical or drug encapsulation and delivery. Adding CAR to the DEWN not only increased the apparent viscosity of the emulsions to 122.2% but also enhanced the thixotropic recovery rate to 87.7%. In general, CAR/DEWN as stabilisers significantly promoted the Pickering emulsions' properties, and provided a possibility for the application of Pickering emulsion in foods. [ABSTRACT FROM AUTHOR]

The optimal extraction conditions of rapeseed cake oil using subcritical R134a/butane were established by response surface methodology. The quality of subcritical R134a/butane extraction oil (SRBEO) was compared with supercritical CO2 extraction oil (SCO2EO) and hexane extraction oil (HXEO). The results showed the highest extraction yield obtained by subcritical R134a/butane in the condition of R134a‐butane ratio of 1.5 kg/kg, at 45°C for 50 min. Compared with SCO2EO and HXEO, the extraction yield and β‐carotene content of SRBEO (87.76%, 357.21 μg/100g) were the highest. The content of phospholipids and canolol in SRBEO (3.01 mg/g, 118.51 mg/100 g) was higher than SCO2EO (not detected, 95.82 mg/100 g) and less than HXEO (25.78 mg/g, 131.85 mg/100 g). The tocopherols in SRBEO were equivalent to SCO2EO but phytosterol content of SRBEO (560.19 mg/100 g) was less than SCO2EO (591.40 mg/100 g). For fatty acids, the three extraction oils had slight difference. Thus, subcritical R134a/butane extraction appeared to be feasible for rapeseed cake oil extraction. [ABSTRACT FROM AUTHOR]

α‐Amylase, an essential biomarker in pancreas related diseases and perform a major role in carbohydrates metabolism. Hence, monitoring the dynamic changes of α‐amylase is crucial for better clinical diagnosis of diseases. However, the existing methods are suffered from low sensitivity, time consumption and indirect assay with aid of tool enzyme or inhibitor of competitive substrates, the rapid and non‐destructive sensing of α‐amylase in biological samples was highly desired. In this work, a very simple tetraphenylethylene motif and γ‐cyclodextrin based supramolecular fluometric sensing system was firstly established. This system has no emission signal in aqueous media for the freely rotation of phenyl rings in the cavity of γ‐cyclodextrin, but the AIE residues can be released in to water after the α‐amylase hydrolysing γ‐cyclodextrin, then turn on the fluorescence. In this system, the detection limit is calculated to be 0.007 U mL−1 in MES buffer with a linear range of 0–0.35 U mL−1, having excellent selectivity to α‐amylase compared to other proteins. At last, our probe can be applied to the quantitative analysis of α‐amylase in human serum, showing potential in point of care testing. How to be a good guest: A supramolecular probe based on the tetraphenylethylene motif and γ‐cyclodextrin host–guest inclusion for α‐amylase recognition was designed and synthesized. The specific cleavage of the 1,4‐glycosidic bonds in cyclodextrin by α‐amylase results in the release of the guest molecule TPESO3Na, a relatively amphiphilic moiety that self‐assembles into a highly fluorescent micelle, thus giving rise to "turn‐on" fluorescent signals. [ABSTRACT FROM AUTHOR]

We analyzed and compared the difference in sinapine concentration in rapeseed meal between the filamentous fungus, Trametes sp 48424, and the yeast, Saccharomyces cerevisiae, in both liquid and solid-state fermentation. During liquid and solid-state fermentation by Trametes sp 48424, the sinapine concentration decreased significantly. In contrast, the liquid and solid-state fermentation process by Saccharomyces cerevisiae just slightly decreased the sinapine concentration (P ≤ 0.05). After the solid-state fermented samples were dried, the concentration of sinapine in rapeseed meal decreased significantly in Saccharomyces cerevisiae. Based on the measurement of laccase activity, we observed that laccase induced the decrease in the concentration of sinapine during fermentation with Trametes sp 48424. In order to eliminate the influence of microorganisms and the metabolites produced during fermentation, high moisture rapeseed meal and the original rapeseed meal were dried at 90°C and 105°C, respectively. During drying, the concentration of sinapine in high moisture rapeseed meal decreased rapidly and we obtained a high correlation coefficient between the concentration of sinapine and loss of moisture. Our results suggest that drying and enzymes, especially laccase that is produced during the solid-state fermentation process, may be the main factors that affect the concentration of sinapine in rapeseed meal. [ABSTRACT FROM AUTHOR]

The double-low rapeseed contains ≤2% erucic acid in its oil and ≤35μmol/g of dry meal. The oil of double-low rapeseed contains very low levels of saturated fatty acids (6%), high levels of oleic acid (≥60%), and intermediate levels of linoleic and linolenic acids (20 %and 10 %, respectively). Because of its higher oil content and numerous agricultural advantages, double-low rapeseed is getting worldwide attention. The rapeseed oil, which was extracted by a traditional process with pre-press and solvent extraction, is of bad quality. Commercial hexane, which has been used as a solvent for crude edible oil extraction, has toxicological and environmental safety issues. Carbon dioxide in its supercritical state has properties and extraction capacities very similar to liquids. Supercritical carbon dioxide extraction is a new technique for oil extraction and is similar to conventional solvent extraction in that the material to be extracted is withdrawn from the substrate by using a solvent. In its supercritical state, carbon dioxide is the most commonly used supercritical solvent due to its nontoxicity, non-flammability, low cost, availability in bulk quantities, ease of removal from the extracted materials, and low critical temperature and pressure (31.06 °C and 7.38 MPa, respectively). To improve the additional value of oils and meals obtained from the cold press cake of double-low dehulled rapeseed, supercritical CO2 is used to extract double-low rapeseed oil and then the quality of the oil and meal obtained is studied. The affection of factors, which includes extraction pressure, temperature, and time effecting on oil yield, is investigated by Box-Behnken's response surface methodology. The model equation for predicting the optimum response values is established by Design Expert software. The adequacy of the model equation for predicting the optimum response values was effectively verified by the validation. The experiment result indicates that affection of extraction pressure and time on oil yield are more significant than extraction temperature. The interaction between extraction pressure and time has a very significant affection on oil yield. The optimum operation parameters of supercritical CO2 extraction are: extraction temperature 40°C, pressure 28MPa, and time 120min.In this optimal condition, the oil yield is 95.08% and is similar to the 95.30% predicted as maximum oil yield by the mathematical model under the condition of temperature 39.66°C and pressure 27.50MPa with extraction time 120 min. The supercritical CO2 extraction of double-low rapeseed oil from dehulled cold press cake has a lighter color and better acid and peroxide value compared to n-hexane extraction. The phospholipid content of oil extracted with supercritical CO2 is 0.051mg/g, which is 1/32 of the n-hexane process, and the vitamin E and total phenolic content are 17.68ug/g and 5.17ug/mL respectively, which are both larger than the n-hexane extraction process. The meal of double-low rapeseed obtained from dehulled cold press cake with supercritical CO2 extraction, which has a superior quality compared to the meal obtained by n-hexane extraction, has lower glucosinolate content, high protein solubility, and better color. These study results can help utilize cold press cake of dehulled double-low rapeseed for high-value purposes. [ABSTRACT FROM AUTHOR]

The double-low rapeseed contains ≤2% erucic acid in its oil and ≤35μmol/g of dry meal. The oil of double-low rapeseed contains very low levels of saturated fatty acids (6%), high levels of oleic acid (≥60%), and intermediate levels of linoleic and linolenic acids (20 %and 10 %, respectively). Because of its higher oil content and numerous agricultural advantages, double-low rapeseed is getting worldwide attention. The rapeseed oil, which was extracted by a traditional process with pre-press and solvent extraction, is of bad quality. Commercial hexane, which has been used as a solvent for crude edible oil extraction, has toxicological and environmental safety issues. Carbon dioxide in its supercritical state has properties and extraction capacities very similar to liquids. Supercritical carbon dioxide extraction is a new technique for oil extraction and is similar to conventional solvent extraction in that the material to be extracted is withdrawn from the substrate by using a solvent. In its supercritical state, carbon dioxide is the most commonly used supercritical solvent due to its nontoxicity, non-flammability, low cost, availability in bulk quantities, ease of removal from the extracted materials, and low critical temperature and pressure (31.06 °C and 7.38 MPa, respectively). To improve the additional value of oils and meals obtained from the cold press cake of double-low dehulled rapeseed, supercritical CO2 is used to extract double-low rapeseed oil and then the quality of the oil and meal obtained is studied. The affection of factors, which includes extraction pressure, temperature, and time effecting on oil yield, is investigated by Box-Behnken's response surface methodology. The model equation for predicting the optimum response values is established by Design Expert software. The adequacy of the model equation for predicting the optimum response values was effectively verified by the validation. The experiment result indicates that affection of extraction pressure and time on oil yield are more significant than extraction temperature. The interaction between extraction pressure and time has a very significant affection on oil yield. The optimum operation parameters of supercritical CO2 extraction are: extraction temperature 40°C, pressure 28MPa, and time 120min.In this optimal condition, the oil yield is 95.08% and is similar to the 95.30% predicted as maximum oil yield by the mathematical model under the condition of temperature 39.66°C and pressure 27.50MPa with extraction time 120 min. The supercritical CO2 extraction of double-low rapeseed oil from dehulled cold press cake has a lighter color and better acid and peroxide value compared to n-hexane extraction. The phospholipid content of oil extracted with supercritical CO2 is 0.051mg/g, which is 1/32 of the n-hexane process, and the vitamin E and total phenolic content are 17.68ug/g and 5.17ug/mL respectively, which are both larger than the n-hexane extraction process. The meal of double-low rapeseed obtained from dehulled cold press cake with supercritical CO2 extraction, which has a superior quality compared to the meal obtained by n-hexane extraction, has lower glucosinolate content, high protein solubility, and better color. These study results can help utilize cold press cake of dehulled double-low rapeseed for high-value purposes. [ABSTRACT FROM AUTHOR]

The quality properties and antioxidant activities of tiger nut (Cyperus esculentus L.) oil produced using mechanical expression with subcritical n -butane extraction (ME-SBE) and supercritical CO 2 extraction (ME-SCO 2 E) were investigated and compared with mechanical expression or critical fluid extraction. Results showed that the highest extraction yield was obtained by ME-SBE (28.47 ± 0.20 g/100 g) and ME-SCO 2 E (28.56 ± 0.24 g/100 g). The content of tocopherols, β -carotene and total phenolic compound in oil extracted by ME-SBE (30.69 ± 0.15 mg/100 g, 160.56 ± 7.98 μg/100 g and 28.79 ± 0.34 mg sinapic acid/100 g, respectively) were the highest, and followed by ME-SCO 2 E oil, For fatty acid composition, five oils were similar and rich in oleic acid (73.81–74.10%) and linoleic acid (8.75–8.89%). Furthermore, oil extracted by ME-SBE presented the uppermost antioxidant activities and oxidation stability, which were correlated with α-tocopherols, total tocopherols and total phenolic compound content. Thus, mechanical expression with subcritical n -butane extraction appeared to be preferable for tiger nut oil extraction. • Profiles of tiger nut oils obtained by five methods were studied. • ME-SBE was proven to be the most suitable method, and the highest yield was 28.5 g/100 g • Tiger nut oils showed a predominance of oleic acid (73.81–74.10%). • Oil extracted by ME-SBE appeared better qualities and antioxidant activities. [ABSTRACT FROM AUTHOR]

Abstract The purpose of the study was to observed the effect of microwave irradiation on the distribution of sinapic acid and its derivatives in hull, endosperm, cotyledon and entire rapeseed. Meanwhile, total phenolic conetent, DPPH and FRAP scavenging capacity of rapeseed were evaluated. Eight main sinapic acid derivatives including sinapine (SP), sinapoyl-glucoside (SG), quercetin-sinapoyl-di-hexosepentose (QSDG), sinapic acid (SA), sinapoyl-malic acid (SM), disinapoyl gentiobioside (DSGG), sinapoylcholine thiocyanate-glucoside (SPTG) and canolol were confirmed in rapeseed by using UPLC-QTOF-MS/MS. After microwave irradiation, canolol in hull, cotyledon, endosperm and whole rapeseed increased by 11.1, 90.0,49.8 and 67.4 mg/100 g, respectively. SP in cotyledon, endosperm and whole rapeseed decreased by 15.9%, 29.1% and 22.1%, respectively. No direct connection was found between canolol formation and sinapine pyrolysis. SG, SA, SM, DSGG and SPTG in endosperm, cotyledon and entire rapeseed decreased significantly except for QSDG. There was no significant different in total phenolic content, DPPH and FRAP scavenging capacity before or after microwave. SP and SA exhibited similar DPPH and FRAP scavenging capacity which were stronger than others. These results indicated microwave irradiation affects the distribution of sinapic acid and its derivatives and contributes to the formation of canolol in rapeseed. Highlights • Eight main SA and its derivatives are confirmed in rapeseed by UPLC-QTOF-MS/MS. • Effects of microwave on the content of SA and derivatives in rapeseed were studied. • Canolol content was effected by SA and its derivatives profile and distribution. • SP and SA possessed stronger DPPH and FRAP scavenging capacity than others. [ABSTRACT FROM AUTHOR]

The linseed gum/cellulose composite hydrogels were successfully fabricated by mixing cellulose and linseed gum solutions dissolved in the NaOH/urea aqueous system and cross-linked with epichlorohydrin. The morphology and structure of the composite hydrogels were investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis (TGA). The swelling ratio and water retention properties were investigated. The results revealed that linseed gum mainly contributed to water adsorption, whereas the cellulose acted as a backbone to strengthen the porous structure. This work provided a simple way to prepare cellulose-based superabsorbent hydrogels, which could be potentially applied as an effective water conservation material in agriculture. [ABSTRACT FROM AUTHOR]

The optimal extraction parameters of Dendranthema indicum extract using supercritical carbon dioxide extraction were organized by response surface methodology (RSM) with Box - Behnken design (BBD). The peak extraction yield (9.37%) was obtained in the condition of 750 W of microwave power, 40 °C of extraction temperature, 26 MPa of extraction pressure, and 105 min of extraction time. Subsequently, molecular distillation was applied to separate essential oil from D. indicum extract. The separation yield of D. indicum essential oil obtained at 80 (DIEO80) and 90 °C (DIEO90) were 0.21 g/100 g and 0.44 g/100 g, respectively, which was lower than those of 100, 110 and 120 °C, while they presented transparent with no precipitate. DIEO90 possessed the strongest antioxidant activities (16.08 μmol TE/g for 1,1-diphenyl-2-picrylhydrazyl scavenging activity, 46.05 μmol TE/g for ferric reducing antioxidant power, respectively). Furthermore, alkenes, alcohols and esters were identified the main volatile flavor components for D. indicum extract and essential oils. The proportions of major contributing components such as 1,8-cineol (6.45%–15.04%), isopinocarveol (6.02%–11.78%), (E)-α-bergamotene (3.02%–5.62%), (E)-β-famesene (2.80%–12.92%), germacrene D (2.83%–8.23%), 6-ethenyl-2,2,6-trimethyloxan-3-ol (5.86%–6.88%), (6-Ethenyl-2,2,6-trimethyl-oxa- n-3-yl) acetate (9.11%–10.51%) and β-elemene (4.16%–6.44%). Though molecular distillation, compounds with low boiling points were enriched in DIEO80 and DIEO90, and compounds with high boiling points were in other oils. Overall, the sequential green process based on supercritical carbon dioxide extraction with molecular distillation is an efficient method for extraction and separation of essential oil. • Supercritical CO 2 extraction combined with molecular distillation is developed to extract and separate essential oil. • Supercritical carbon dioxide extraction is optimized by response surface methodology (RSM) with Box- Behnken design (BBD). • Molecular distillation at lower temperature obtained lower yield but superior properties. • Dendranthema indicum essential oil obtained at 90 °C presented the strongest antioxidant activities. [ABSTRACT FROM AUTHOR]

Flaxseed powder is a widely used nutrient-rich food, valued for its flavor as well as its nutritional value. The effect of peeling on the flavor profiles of raw and microwaved flaxseed powder remains unclear. In this study, the volatile components of flaxseed powder were analyzed using solvent-assisted flavor evaporation combined with gas chromatography-mass spectrometry-olfactometry. Fifty-two odor-active compounds were identified, with flavor dilution (FD) factors ranging from 3 to 729. Hexanal, d -limonene, 1-hexanol, β -phellandrene, α -phellandrene, and nonanal with Odor Activity Values (OAV≥1), which could impart green-like, fresh-like, and mint-like notes, were the typical odorants in raw flaxseed powders. Microwaved powders had more intense roasted and woody notes than raw powders. Peeling treatment had a significant effect on the aroma of microwaved flaxseed powder, but caused only a slight change in the flavor profiles of the raw powders. The key aroma differences in the two kinds of microwaved powders were mainly due to the levels of 2-methylbutanal, 2-methylpyrazine 6-methyl-5-hepten-2-ol, 4-hydroxy-2,5-dimethylfuran-3-one, 2-ethyl-3,6-dimethylpyrazine, and 2-ethyl-3,5-dimethylpyrazine. This work provides a basis for the improvement of the aroma of flaxseed products. • Volatile components of flaxseed powder were analyzed. • Fifty-two odor-active compounds were identified. • Microwaved powders had more intense roasted and woody notes than raw powders. • Peeling had a significant effect on the aroma of microwaved flaxseed powder. [ABSTRACT FROM AUTHOR]

The free-radical-mediated formation mechanism of polar polymeric triglycerides (TAGs) was derived based on the formation of lipid-derived radicals and the degradation of TAGs in palm oil (PO), rapeseed oil (RO), and sunflower oil (SO). The experimental spectra were simulated by alkoxyl, alkyl, and 5-dimethyl-1-pyrroline N-oxide (DMPO)-oxidized adducts. DMPO-oxidized adducts were the main radical adducts in the initial stage. Then, alkyl radical adducts became the dominating radical adducts after 12 min in PO and RO. The intensity of alkyl radical adducts was the highest in SO. Therefore, based on the bimolecular reaction, polar polymeric TAGs were mainly bonded by -C-O-O-C- in the initial stage and then by -C-C- and -C-O-C- after 30 min. Besides, according to the correlation analysis between the amounts of polar polymeric TAGs and the degradation of TAGs, the main structures of polar polymeric TAGs in PO, RO, and SO were POL-LOP, POL-OOP, and POO-OOP; OLL-LnLO, OLLn-OLnO, OOO-OLO, and OLLn-OOO; and LLL-LLO, LLL-LLL, and OLL-LLO, respectively.

α-Amylase, an essential biomarker in pancreas related diseases and perform a major role in carbohydrates metabolism. Hence, monitoring the dynamic changes of α-amylase is crucial for better clinical diagnosis of diseases. However, the existing methods are suffered from low sensitivity, time consumption and indirect assay with aid of tool enzyme or inhibitor of competitive substrates, the rapid and non-destructive sensing of α-amylase in biological samples was highly desired. In this work, a very simple tetraphenylethylene motif and γ-cyclodextrin based supramolecular fluometric sensing system was firstly established. This system has no emission signal in aqueous media for the freely rotation of phenyl rings in the cavity of γ-cyclodextrin, but the AIE residues can be released in to water after the α-amylase hydrolysing γ-cyclodextrin, then turn on the fluorescence. In this system, the detection limit is calculated to be 0.007 U mL -1 in MES buffer with a linear range of 0-0.35 U mL -1 , having excellent selectivity to α-amylase compared to other proteins. At last, our probe can be applied to the quantitative analysis of α-amylase in human serum, showing potential in point of care testing., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The high catalytic activity, specificity and stability of immobilized lipase have been attracting great interest. How to reduce the cost of support materials has always been a hot topic in this field. Herein, for the development of low-cost immobilized lipase, we demonstrate an amphiphilic polyvinylpyrrolidone (PVP) grafted on silicone particle (SP) surface materials (SP-PVP) with a rational design based on interfacial activation and solution polymerization. Meanwhile, hydrophilic pristine SP and hydrophobic polystyrene-corded silicone particles (SP-Pst) were also prepared for lipase immobilization. SP-PVP was characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and thermogravimetry. Our results indicated that the lipase loading amount on the SP-PVP composites was about 215 mg of protein per gram. In the activity assay, the immobilized lipase SP-PVP@CRL exhibited higher catalysis activity and better thermostability and reusability than SP@CRL and SP-Pst@CRL. The immobilized lipase retained more than 54% of its initial activity after 10 times of re-use and approximately trended to a steady rate in the following cycles. By introducing the interesting amphiphilic polymer to this cheap and easily obtained SP surface, the relative performance of the immobilized lipase can be significantly improved, facilitating interactions between the low-cost support materials and lipase., Competing Interests: We declare we have no competing interests.

Herein, a promising carrier, graphene oxide (GO) decorated with ZnO nanoparticles, denoted as GO/ZnO composite, has been designed and constructed. This carrier was characterized by X-ray powder diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and thermogravimetry. Then, Candida rugosa lipase (CRL) was immobilized onto the GO-based materials via physical adsorption. Our results indicated that the lipase loading amount on the GO/ZnO composites was about 73.52 mg of protein per g. In the activity assay, the novel immobilized lipase GO/ZnO@CRL, exhibited particularly excellent performance in terms of thermostability and reusability. Within 30 min at 50 °C, the free lipase, GO@CRL and ZnO@CRL had respectively lost 64%, 62% and 41% of their initial activity. However, GO/ZnO@CRL still retained its activity of 63% after 180 min at 50 °C. After reuse of the GO/ZnO@CRL 14 times, 90% of the initial activity can be recovered. Meanwhile, the relative activity of GO@CRL and ZnO@CRL was 28% and 23% under uniform conditions. Hence, GO-decorated ZnO nanoparticles may possess great potential as carriers for immobilizing lipase in a wide range of applications., Competing Interests: The authors declare no conflict of interest.

A study was conducted to evaluate the effect of microwave heating on the efficacy of expeller pressing of rapeseed and mustard seed and the composition of expeller meals in two types of Brassica napus rapeseed (intermediate- and low-glucosinolate) and in Brassica juncea mustard (high-glucosinolate). Following microwave treatment, the microstructure of rapeseed using transmission electron microscopy showed a significant disappearance of oil bodies and myrosin cells. After 6 min of microwave heating (400 g, 800 W), the oil content of rapeseed expeller meal decreased from 44.9 to 13.5% for intermediate-glucosinolate B. napus rapeseed, from 42.6 to 11.3% for low-glucosinolate B. napus rapeseed, and from 44.4 to 14.1% for B. juncea mustard. The latter values were much lower than the oil contents of the corresponding expeller meals derived from the unheated seeds (i.e., 26.6, 22.6, and 29.8%, respectively). Neutral detergent fiber (NDF) contents showed no differences except for the expeller meal from the intermediate-glucosinolate B. napus rapeseed, which increased from 22.7 to 29.2% after 6 min of microwave heating. Microwave treatment for 4 and 5 min effectively inactivated myrosinase enzyme of intermediate-glucosinolate B. napus rapeseed and B. juncea mustard seed, respectively. In low-glucosinolate B. napus rapeseed the enzyme appeared to be more heat stable, with some activity being present after 6 min of microwave heating. Myrosinase enzyme inactivation had a profound effect on the glucosinolate content of expeller meals and prevented their hydrolysis to toxic breakdown products during the expelling process. It appeared evident from this study that microwave heating for 6 min was an effective method of producing expeller meal without toxic glucosinolate breakdown products while at the same time facilitating high yield of oil during the expelling process.