Comparison of ultrasonic and CO2laser pretreatment methods on enzyme digestibility of corn stover.

To decrease the cost of bioethanol production, biomass recalcitrance needs to be overcome so that the conversion of biomass to bioethanol becomes more efficient. CO(2) laser irradiation can disrupt the lignocellulosic physical structure and reduce the average size of fiber. Analyses with Fourier transform infrared spectroscopy, specific surface area, and the microstructure of corn stover were used to elucidate the enhancement mechanism of the pretreatment process by CO(2) laser irradiation. The present work demonstrated that the CO(2) laser had potential to enhance the bioconversion efficiency of lignocellulosic waste to renewable bioethanol. The saccharification rate of the CO(2) laser pretreatment was significantly higher than ultrasonic pretreatment, and reached 27.75% which was 1.34-fold of that of ultrasonic pretreatment. The results showed the impact of CO(2) laser pretreatment on corn stover to be more effective than ultrasonic pretreatment.

Evaluation of antioxidant and antiproliferative properties of three Actinidia (Actinidia kolomikta, Actinidia arguta, Actinidia chinensis) extracts in vitro.

The total phenolic content, total flavonoid content, vitamin C content, and antioxidant activities of ethanol extracts from different kiwifruit varieties (Actinidia kolomikta, Actinidia arguta, Actinidia chinensis) were determined in this study. Multiple scavenging activity assays including the hydroxyl radical, O(2) (-)·radical, DPPH, and the ABTS(+) radical scavenging activity assays were used to identify the antioxidant activities of Actinidia extracts. The cell viability of HepG2 and HT-29 cells was also examined in this study. The results demonstrated that the Actinidia kolomikta extract had a higher antioxidant activity than the other two Actinidia extracts. There is a positive correlation between antioxidant activity and the polyphenols and vitamin C content in all three extracts (R(2) ≥ 0.712, p < 0.05). The Actinidia arguta extract had the highest inhibitory effect on HepG2 and HT-29 cell growth. These results provide new insight into the health functions of fruit and demonstrate that Actinidia extracts can potentially have health benefits.

Nondestructive Testing for Wheat Quality with Sensor Technology Based on Big Data.

Nondestructive testing with sensor technology is one of the fastest growing and most promising wheat quality information analysis technologies. Nondestructive testing with sensor technology benefits from the latest achievement of many disciplines such as computer, optics, mathematics, chemistry, and chemometrics. It has the advantages of simplicity, speed, low cost, no pollution, and no contact. It is widely used in wheat quality analysis and testing research. This article summarizes nondestructive testing with sensor technology for wheat quality, including the mechanical model, hyperspectral technology, Raman spectroscopy, and near-infrared techniques for wheat mechanical properties, storage properties, and physical and chemical properties (such as moisture, ash, protein, and starch) in the past decade. Based on the current research progress, big data technology needs a lot of research in spectral data mining, modeling algorithm optimization, model robustness, etc. to provide more data support and method reference for the research and application of wheat quality.

Physicochemical Properties and Digestion Characteristics of Corn Starch Esterfied by Malic Acid.

The objective of this study was to evaluate the effects of different degree of substitution on structural characteristics and crystalline properties of resistant starch esterfied by L-malic acid. With the deepening of the esterification reaction, malate starches particles became larger, particle surface cracks and grooves increased which led to a decline in whiteness of malate starches. With the increase in the degree of substitution (DS), the initial phase transition temperatures (To) and endothermic enthalpies (ΔH) of malate starch gradually decreased. The XRD results indicated that with the increase of DS, the diffraction peak at 15.1° disappeared in the spectrum. When the DS of malate starches reached 0.116, the content of resistant starch (RS) accounted for the majority of the total starch.

Fractal kinetic analysis of the enzymatic saccharification of CO2 laser pretreated corn stover.

The enzymatic hydrolyses of laser pretreated corn stover as a novel pretreatment method were examined to establish a simplified kinetic model for the complicated hydrolysis process. The time dependence of the total reducing sugars amount was closely related to the amounts of cellulosic materials and amounts of cellulase. The evaluated model fitted very well with the experimental data of enzymatic hydrolysis of laser pretreated corn stover under different conditions, including cellulase loading, nature of substrate, substrate loading in the reaction medium. The results indicated that the complex kinetics of cellulase enzymatic saccharification could be assessed with the fractal kinetic model. The cellulase enzymatic reaction process was effectively predicted and controlled with the kinetic model. The result showed that the model could effectively reflect dynamic process of enzyme hydrolysis.

Protective effect of anthocyanins from lingonberry on radiation-induced damages.

There is a growing concern about the serious harm of radioactive materials, which are widely used in energy production, scientific research, medicine, industry and other areas. In recent years, owing to the great side effects of anti-radiation drugs, research on the radiation protectants has gradually expanded from the previous chemicals to the use of natural anti-radiation drugs and functional foods. Some reports have confirmed that anthocyanins are good antioxidants, which can effectively eliminate free radicals, but studies on the immunoregulatory and anti-radiation effects of anthocyanins from lingonberry (ALB) are less reported. In this experiment, mice were given orally once daily for 14 consecutive days before exposure to 6 Gy of gamma-radiation and were sacrificed on the 7th day post-irradiation. The results showed that the selected dose of extract did not lead to acute toxicity in mice; while groups given anthocyanins orally were significantly better than radiation control group according to blood analysis; pretreatment of anthocyanins significantly (p < 0.05) enhanced the thymus and spleen indices and spleen cell survival compared to the irradiation control group. Pretreatment with anthocyanins before irradiation significantly reduced the numbers of micronuclei (MN) in bone marrow polychromatic erythrocytes (PCEs). These findings indicate that anthocyanins have immunostimulatory potential against immunosuppression induced by the radiation.

Optimization of CO2 laser-based pretreatment of corn stover using response surface methodology.

CO2 laser pretreatment to improve the enzymatic hydrolysis of corn stover for production of monosaccharide, was investigated. Response surface methodology (RSM), at a three-variable, three-level experiment Box-Behnken design (BBD) established the following optimum pretreatment parameters: time, 67.53 min; power, 264.33 W; and liquid-to-solid ratio, 21.29:1 (mL/g). Under these conditions, the reducing sugars produced was 4.941 mg/mL for cellulase hydrolysis. This amount matched the predicted value and increased cellulase hydrolysis from 14.47% to 30.84%. Scanning electron microscopy (SEM) showed that CO2 laser pretreatment converted the smooth into a rough and porous surface, which promoted the enzyme access and resulted in a high specific reducing sugars production rate.