The differences of volatile odorants of rice at different roasting levels were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) using fingerprints combined with principal component analysis (PCA). GC-IMS and PCA could distinguish the different roasting levels of rice and the results showed that a total of 47 representative flavor compounds were detected in four samples from all roasting stages. The aroma components of roasted rice are mainly aldehydes and ketones, furans and pyrroles, as well as a large number of phenols, esters and alcohols, which make up the special aroma flavor of roasted rice. It can be seen that the flavor characteristics of roasted rice can be reflected more fully when the rice is roasted in medium (18 min), and can have more fruit wood, cream and roasted aromas. The PCA based on the signal intensity of the detected volatile compounds revealed effective differentiation of samples from different stages into comparatively independent spaces. Thus, the differences of volatile compounds from different roasting stages of rice were determined, and the flavor fingerprints of that can be successfully established using HS-GC-IMS and PCA.

Mathanobatins (Mb, Mbtins) were immobilized successfully on nanometer-sized gold colloid particles associated with β-mercaptoethylamine. The structures of Mb functionalized gold nanoparticles were characterized and confirmed by UV-vis spectroscopy (UV-vis), FTIR spectra and electrochemical analyses. Direct electron transfer between Mb or copper-loading Mbtins and the modified electrode was investigated without the aid of any electron mediator. The copper-loading Mbtins act as a better electrocatalyst for the reduction of H2O2 than Mb. The copper-loading Mb, with which gold nanoparticles were functionalized, as a model enzyme, was immobilized on gold electrode to construct a novel H2O2 biosensor. In pH 6.4 phosphate buffer solution, the reduction and oxidation peak potentials of Mb functionalized gold nanoparticles modified Au electrode (copper-loading Mbtins) were 0.115 and 0.222 V. On the surface, capacitance per unite area (Cd) of Mb functionalized gold nanoparticles modified electrode were 38 μF cm-2. The immobilized Mb displayed the features of a peroxidase and gave an excellent electrocatalytic response to the reduction of H2O2. The detection limit of Mb functionalized gold nanoparticles (copper-loading) were 09 × 10-5 mA/M (S/N = 3). The Michaelis-Menten constant (Km) was 0.787 mM. Good stability and sensitivity were assessed for the biosensor.

The study investigated the changes of lipid metabolism histology in rats under the three groups of dietary modifications after dietary intervention in (Sprague-Dawley, SD) SD rats using lotus seed reconstituted rice, ordinary rice, and high-fat feed made from lotus seed starch-rice flour after extrusion and puffing. It was found that the high-fat feed could lead to the disorder of lipid metabolism in rats, and the accumulation of lipid metabolism substances caused by the high-fat feed was significantly increased; the intervention of ordinary rice and high-dose reconstituted rice revealed that the high-dose reconstituted rice could improve the disorder of lipid metabolism and the accumulation of lipid substances caused by the high-fat feed to a greater extent. The main lipid substances were PC, TAG, Cer, CE, SM, PE, LPC, Acar, DAG, FAHFA, OxPI, PI, SQDG, Cer/NS, GlcADG, HBMP, Cer/NDS, HexCer/NS, etc., and the study confirmed that the reconstituted rice made from lotus seeds in this experiment was better than ordinary rice, and the high-dose reconstituted rice obtained from the study has a better modulating effect on lipid metabolism disorders and organism damage caused by high-fat feed.

High fat diet may cause obesity, diabetes, atherosclerosis, hypertension, hyperlipidemia and other diseases, and even mortality. The recombinant rice based on mixing lotus seed starch and broken rice flour was used to feed high-fat diet rats, and its effects on body weight and organ index were determined. The changes of intestinal flora in rats were studied by macrogenomic technology, and the effects of lotus seed starch-broken rice flour recombinant rice (LSBR) on intestinal flora in rats were discussed. The results showed that adding enough LSBR could effectively inhibit the weight gain of rats, reduce the liver index from 0.3498 to 0.2836, and the kidney index from 0.0079 to 0.0072. The reduction of intestinal flora abundance and diversity caused by high-fat diet were improved, the relative abundance ratio of Firmicutes/Bacteroidete was reduced from 11.04 to 2.17, while the relative abundance of beneficial bacteria was increased.