Structural Changes in Milled Wood Lignin (MWL) of Chinese Quince (Chaenomeles sinensis) Fruit Subjected to Subcritical Water Treatment.

Subcritical water treatment has received considerable attention due to its cost effectiveness and environmentally friendly properties. In this investigation, Chinese quince fruits were submitted to subcritical water treatment (130, 150, and 170 °C), and the influence of treatments on the structure of milled wood lignin (MWL) was evaluated. Structural properties of these lignin samples (UL, L130, L150, and L170) were investigated by high-performance anion exchange chromatography (HPAEC), FT-IR, gel permeation chromatography (GPC), TGA, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 2D-Heteronculear Single Quantum Coherence (HSQC) -NMR, and 31P-NMR. The carbohydrate analysis showed that xylose in the samples increased significantly with higher temperature, and according to molecular weight and thermal analysis, the MWLs of the pretreated residues have higher thermal stability with increased molecular weight. The spectra of 2D-NMR and 31P-NMR demonstrated that the chemical linkages in the MWLs were mainly ß-O-4' ether bonds, ß-5' and ß-ß', and the units were principally G- S- H- type with small amounts of ferulic acids; these results are consistent with the results of Py-GC/MS analysis. It is believed that understanding the structural changes in MWL caused by subcritical water treatment will contribute to understanding the mechanism of subcritical water extraction, which in turn will provide a theoretical basis for developing the technology of subcritical water extraction.

Extraction of Fenugreek (Trigonella foenum-graceum L.) Seed Oil Using Subcritical Butane: Characterization and Process Optimization.

In this study, the subcritical butane extraction process of fenugreek seed oil was optimized using response surface methodology with a Box-Behnken design. The optimum conditions for extracted oil from fenugreek seed was as follows: extraction temperature of 43.24 °C , extraction time of 32.80 min, and particle size of 0.26 mm. No significant differences were found between the experimental and predicted values. The physical and chemical properties of the oil showed that the oil could be used as edible oil. Fatty acid composition of oils obtained by subcritical butane under the optimum conditions and by accelerated solvent extraction showed negligible difference. The oils were rich in linoleic acid (42.71%-42.80%), linolenic acid (26.03%-26.15%), and oleic acid (14.24%-14.40%). The results revealed that the proposed method was feasible, and this essay shows the way to exploit fenugreek seeds by subcritical butane extraction under the scope of edible oils.

Subcritical Fluid Extraction of Chinese Quince Seed: Optimization and Product Characterization.

Chinese quince seed (CQS) is an underutilized oil source and a potential source of unsaturated fatty acids and α-tocopherol-rich oil. Subcritical fluid (SCF) extraction is executed at lower pressures and temperatures than the pressures and temperatures used in supercritical fluid extraction. However, no studies on the SCF extraction of CQS oil are reported. Therefore, the objective of this study was to evaluate the use of SCF for the extraction of CQS oil and to compare the use of SCF with the classical Soxhlet (CS) and supercritical CO2 (SC-CO2) extraction methods. Response surface methodology (RSM) was used to investigate the extraction conditions: temperature (45-65 °C), time (30-50 min), and solvent/solid ratio (5-15 mL/g). The optimization results showed that the highest yield (27.78%) was obtained at 56.18 °C, 40.20 min, and 12.57 mL/g. The oil extracted by SCF had a higher unsaturated fatty acid content (86.37%-86.75%), higher α-tocopherol content (576.0-847.6 mg/kg), lower acid value (3.97 mg/g), and lower peroxide value (0.02 meq O2/kg) than extractions using CS and SC-CO2 methods. The SCF-defatted meal of oilseed exhibited the highest nitrogen solubility index (49.64%) and protein dispersibility index (50.80%), demonstrating that SCF extraction was a promising and efficient technique as an alternative to CS and SC-CO2 methods, as very mild operating conditions and an eco-friendly solvent can be used in the process with maximum preservation of the quality of the meal.

Process optimization and characterization of fragrant oil from red pepper (Capsicum annuum L.) seed extracted by subcritical butane extraction.

BACKGROUND: Red pepper seeds account for 450-500 g kg-1 of the total pepper weight and are often discarded as waste. In this study, process optimization and characterization of fragrant oil from roasted red pepper seed extracted by subcritical butane extraction were carried out. RESULTS: The optimal conditions of extraction were a temperature of 74.61 °C, a time of 68.65 min and a liquid/solid ratio of 30.24:1. The oil had a refractive index (25 °C) of 1.471, a relative density of 0.900, an acid value of 1.421 mg g-1 oil, an iodine value of 127.035 g per 100 g, a saponification value of 184.060 mg KOH g-1 , an unsaponifiable matter content of 12.400 g kg-1 , a peroxide value of 2.465 meq. O2 kg-1 and a viscosity of 52.094 cP. The main fatty acids in the oil were linoleic acid (72.95%) followed by palmitic acid (11.43%) and oleic acid (10.00%). The oil showed desirable thermal and oxidative stability. A total of 19 volatile compounds, mostly aldehydes and alkenes, were identified from the oil. CONCLUSION: The results indicated that the method is appropriate for the preparation of fragrant red pepper seed oil, and the oil is suitable for used as edible oil. © 2016 Society of Chemical Industry.

[Raman spectroscopy analysis of impact of UV radiation on linoleic acid oxidation].

The authors studied on self oxidation of linoleic acid and the effect of UV irradiation on oxidation of linoleic by Raman spectroscopy. The result reflects that:the intensity of 1 266 cm' which stands for ==CH olenic hydrogen in-plane bend is diminished, and it disappeared at 72 hours after the oxidation beginning. That indicates that double bond was lost or reduced. upsilon(C==C) and the carboxylic acid C==O vibrations are lies in 1 658 cm(-1). The intensity of 1 658 cm(-1) was increased in the beginning and decreased then. At the initial stage in the reaction, rearrangement of carbon chains and the formation of carboxylic acids caused the increasing. Later in the reaction, carboxyl of linoleic acid reacted with the generated hydroxy acids, hydroxy aldehyde. So it decreased. UV irradiation accelerated the oxidation reaction starting, increased the speed of the oxidation reaction. All the result shows that the changes of Raman spectroscopy indicate the changes of bulky group in fatty acid oxidation process and the effect of UV irradiation. It provides an effective research tool for the mechanism of lipid peroxidation reaction.

Effect of various drying pretreatments on the structural and functional properties of starch isolated from Chinese yam (Dioscorea opposita Thumb.).

The objective of the present investigation was to compared the structural and functional properties of starch isolated from fresh raw Chinese yam (FYS) and the Chinese yam after freeze-drying pretreatment (FDS), after hot-air drying pretreatment (HADS), after subcritical dimethyl ether dewaterization pretreatment (SDDS). Freeze-drying (FD) process reduced the short-and long-range molecular order of Chinese yam starch. Hot-air drying (HAD) process promoted the formation of ordered structure of starch granules. SEM images displayed the presence of protein-starch complexes in the HADS and SDDS samples. The FDS had the smallest Mw of amylopectin with 4.09 × 106 g/mol, but the Mw values of amylose molecules for FYS was highest. The branch chain length of amylopectin in HADS had a smaller proportion of short chains and less long chains and higher proportion of long chains compared with other starches. These molecular structure changes caused by the various drying pretreatment processes, resulting in the difference in functional properties including solubility and swelling power, gelatinization parameters, pasting characteristics and rheological properties. This study provided important information for the suitable application of starches isolated from various dried Chinese yam.

Gene expression of halophyte Kosteletzkya virginica seedlings under salt stress at early stage.

Gene differential expression of Kosteletzkya virginica seedlings under salt stress at two time points (2, 24 h) in roots and leaves was analyzed using the cDNA-amplified fragment length polymorphism (cDNA-AFLP) technique. Polymorphic transcript-derived fragments (TDFs) among control plants and salt-treated plants were grouped into four main differential expression patterns: repression (A), de novo induction (B), up-regulation (C) and down-regulation (D). Among them, 34 differentially expressed gene fragments were homologous to known genes from other species and 4 were sequences with unknown functions. These differentially expressed genes can be classified into four groups according to their putative functions: (1) genes for re-establishing ion homeostasis and protecting the plant from stress damage; (2) genes involved in metabolism or energy and resuming plant growth and development under salt stress; (3) genes involved in regulation of gene expression; (4) genes for signal transduction. Changes of eight differentially expressed genes were confirmed by quantitative real time RT-PCR.

[Absorption spectrum study of HeLa cells treated with vacuum and low-energy ions implantation].

Mineral oil was selected to protect HeLa cells from water evaporation during low-energy ions implantation in the present paper. Then, HeLa cells having been treated with vacuum and low-energy N+ ions implantation were used to collect ultraviolet absorption spectrum by spectrophotometer. Analytical results indicated that HeLa cells had some characteristic absorption peaks near 202 and 260 nm, respectively. And then the study also found: (1) The spectral intensity increased with the vacuum treatment time. In addition, the effect of vacuum on cellular spectrum was greater than that of mineral oil. (2) The influence of low energy N+ ions on absorption spectrum was far more than that of vacuum. (3) The spectral intensity increased with the implantation dose. According to these results, the effect of low-energy N+ ions implantation and vacuum on tumorous cells (HeLa cells), especially on the molecular configuration and component of tumorous cells (HeLa cells) was discussed. In a word, this study provides a basis for further research on the functionary mechanism of low-energy ions implantation on biomaterial.

Structural elucidation of lignin-carbohydrate complexes (LCCs) from Chinese quince (Chaenomeles sinensis) fruit.

The lignin-carbohydrate complexes (LCCs) of the mesocarp (MS) and near the endocarp (NE) of Chinese quince (Chaenomeles sinensis) fruits were analyzed using three different methods of fractioning: milled wood lignin (MWL), LCC extracted from crude MWL with acetic acid (LCC-AcOH), and Bjorkman LCC. The MWL and LCC fractions were characterized by carbohydrate composition analysis, SEC, FT-IR, Py-GC/MS, thermal analysis and 2D HSQC NMR. Notably, large amounts of arabinose and galactose remained in the Björkman LCC fractions suggesting a chemical bond between the lignin and pectin. MWL and LCC-AcOH fractions showed better thermal stability than the Björkman LCC fractions. The structure of MS lignin was similar to that of NE lignin; however, fractions from the different fractionation methods revealed differences. The MWL fractions were rich in benzyl ether and γ-ester linkages, while the Björkman LCC fractions contained phenyl glycoside and γ-ester linkages, and the LCC-AcOH fractions contained phenyl glycoside and benzyl ether linkages. These findings are helpful in understanding the nature of lignin and LCC in Chinese quince fruits and provide a theoretical support for their potential application.

Structural characterization of Chinese quince fruit lignin pretreated with enzymatic hydrolysis.

Lignin is an increasingly valuable raw material for industrial, pharmaceutical and the food industries; natural antioxidants are also being used more and more widely. The Chinese quince fruits have an abundance of lignins with antioxidant properties; however, the lignins cannot be isolated by the methods conventionally used on other sources (e.g., wood, straw). In this investigation, multi-enzymatic hydrolytic pretreatments were used to isolate lignins from Chinese quince fruit, and the structures of these multi-enzyme mixture lignin (EML) fractions were then analyzed and compared with conventional cellulolytic enzyme lignin (CEL). EML fractions are structurally similar to CEL fractions except for an increased S/G ratio, greater number of ß-O-4 linkages, higher average molecular weight and decreased thermal stability. The EML-2 fraction in particular seemed most representative of the lignins isolated, and it exhibited the highest antioxidant activity in comparison with CEL and other EML fractions.

Acetic acid lignins from Chinese quince fruit (Chaenomeles sinensis): effect of pretreatment on their structural features and antioxidant activities.

In this study, three pretreatment processes were evaluated for their effects on the structural features and antioxidant activities of lignins extracted by the acetosolv process from the fruit of Chinese quince. The three pretreatments included dephenolization, sugar removal, and multiple processes (a combination of both dephenolization and sugar removal). The results showed that after sugar removal pretreatment, the carbohydrate content, the molecular weight and S/G value of the lignin fractions decreased. However, after dephenolization pretreatment, the carbohydrate content and the molecular weight of the lignin fractions increased. After sugar removal and dephenolization, there were increases in the temperatures corresponding to the maximal rate of decomposition (DTGmax) in all lignin fractions. The radical scavenging index of lignin after sugar removal pretreatment was higher compared to other pretreatments and no treatment. The results of these tests showed that sugar removal, as a pretreatment, enhanced lignin extraction, yielding pure and highly functional lignins. Additionally, dephenolization or multiple process were beneficial to the acquisition of macromolecular lignins. All the results provided references for the biorefinery of biomass rich in polyphenol and sugar compounds.

Low-energy ion beam promotes the transcription and transposition of the Copia-retrotransposons in wheat (Triticum aestivum L.).

LTR-retrotransposons are genetic elements having the direct long terminal repeats (LTRs). It can move via an RNA intermediate within genomes and is an important fraction of eukaryote genomes. Low-energy N(+) ion beam promoted the transcription of the copia-retransposons in those wheat (cv. 'Zhoumai 16', which were radiated and allowed to grow for 24 h and 48 h from the planting. Relative expression ratio of the copia-retransposons was elevated in different degrees (with a max 40 fold) in wheat plants treated with different doses of N(+) beam, comparing to that in the controls. The molecule markers of the IRAP and REMAP to the DNA isolated from the 14-d leaves of wheat plants treated with the low-energy N(+) beam showed that the transposition of some copia-retransposons was re-activated. The enhanced transcription of the copia-retransposons in wheat could weaken or enhance the expression of their nearby genes. The transposition of the retrotransposon in genome can change the primary structure of the functional DNA fragments of chromosomes, and it can also be visualized as the appearance of a new phenotype of plants. In the mid 1980s, the biological effects of low-energy ion beam were recognized and demonstrated experimentally. Hence, it suggests that the enhanced transcription and the re-activated transposition of the retrotransposons are partially attributed to the biological effect of low-energy ion beam.

[Differential expression of the proteins in endosperms of rice with different chromosome sets].

The present paper compared the major storage proteins in starchy endosperm of four autotetraploid rice lines with that of their corresponding diploid rice lines. The content of albumin, globulin, prolamin and glutelin in each sample was determined respectively. The structure and expression pattern of each storage protein was investigated using one-dimensional SDS-PAGE. Our results showed that the protein content of each fraction in endosperm of autotetraploid rice line is mostly higher than that of its corresponding diploid rice line. However, the SDS-PAGE analysis showed that the subunit types of each storage protein of autotetraploid rice line was generally homologous to that of its corresponding diploid rice line, except for one differential band observed on SDS-PAGE gels of total protein fraction and another on the SDS-PAGE gels of albumin and globulin fraction. These results indicated that duplicated genes in autotetraploid rice ac-quired the same expression patterns as that seen in its corresponding diploid rice. It was suggested that the doubling of chromosome sets did not change the protein expression profile but the protein expression level in the starchy endosperm of autotetraploid rice.

[Prediction of protein content of intact wheat seeds with near infrared reflectance spectroscopy (NIRS)].

In the present article, the measurement of intact wheat seeds' protein content with near infrared reflentance spectroscopy(NIRS) was studied. The wavelength range of 1 100-2 498 nm was used. The distinguishability of NIRS machine was 2 nm. Firstly the representative wheat samples with different protein contents were selected and the original spectra of wheat were obtained using NIRS machine. Then through scatter correction and maths treatment, spectrum noise were decreased. Finally regression methods used multiple linear regression, principal component regression and modified partial least squares respectively. The result showed that after optimizing all the factors, the best calibration model of equation was chosen using "first derivative" +"Standard Multiplicative Scatter Correction, SMSC"+"Modified Partial Least Squares, MPLS". RSQ, SECV and 1-VR of the obtained calibration model were 0. 94, 0. 42 and 0. 87 respectively. A set of representative individual wheat samples were uesed to check the model, and prediction coefficient of determination was 0.88. Protein content of wheat could be preidicted quickly and scathelessly by using the NIRS measurement. It was feasible to be used in early generation selection in wheat quality breeding process.

[XPS research on thymine implanted by low energy N+].

The induced variation mechanism of low energy ion beam implantation into a creature has attracted a great attention. DNA was the target of radiation. XPS analysis of thymine sample implanted by low energy N+ was studied. It was found that the relative content of C, N and O changed in the implanted samples. The content of N and O decreased, while that of C increased. Subtle structure of C, N and O was studied. It was found that the peak location of O(1s) shifted. The peak number of N(1s) changed from one to three, while that of C(1s) changed from two to one. The results indicated that the chemical environment and physical structure changed greatly by implantation. N+ implantation could lead to destruction and change of thymine molecular structure.

Structure characterization and antioxidant activity of polysaccharides from Chinese quince seed meal.

In the present study, three polysaccharide fractions, QSMP-1, QSMP-2, and QSMP-3, were isolated and purified from the seed meal of Chinese quince. These fractions' structures were investigated by high performance anion exchange chromatography (HPAEC), gel permeation chromatography (GPC), Fourier transform infrared (FT-IR), and nuclear magnetic resonance (NMR), and their antioxidant activities were assessed. The results showed that QSMP-1 is a novel polysaccharide with a backbone mainly composed of →4)-Glcp-(1→, →6)-Glcp-(1→, →6)-Galp-(1→, →2, 3, 4)-Xylp-(1→. The side chains consist of →4)-Arap-(1→, →3, 4)-Arap-(1→, →2)-Galp-(1→, →4)-Manp-(1→, →3)-Galp-(1→, and →3, 6)-Glcp-(1→ with the non-reducing terminals Glcp and Galp. QSMP-1 exhibited effective antioxidant activities by ferrous ion chelation and superoxide anion-scavenging in a dose-dependent manner. These investigations of the polysaccharides from the seed meal of Chinese quince provide a scientific basis for the use of the by-products of quince seed oil processing, particularly as an ingredient in functional foods and medicines.

[Study on ion beam mutagenizing of the Trichosporon lactis T for enantioselective separation of ibuprofen].

The initial strain, Trichosporon Lactis T, isolated from soil sample, having the capability of enantioselectively hydrolyzing S-isomer of racemic ibuprofen ethyl-ester into the corresponding S-ibuprofen, was implanted by 30 KeV, 1 x 10(15) ions/cm2 - 5 x 10(15) ions/cm2 low-energy N+ for the purpose of obtaining mutants with high-efficiency hydrolyzing enzyme to produce active S-ibuprofen. Under the dosage of 30 KeV, 4 x 10(15) ions/cm2, the mutation rate is the highest, with 32.9 % positive and 37.1% negative mutant, respectively. Therefore, 30 KeV, 4 x 10(15) ions/cm2 is chosen as the optimal implantation dosage. Under optimal implantation dosage, seven mutants with high-efficiency hydrolyzing enzyme are selected after N+ implantation. The genetic stability test shows that T. lactis K1, one of the seven mutants, has a stable hydrolyzing ability during consecutive five-generation. The enzyme activity of T. lactis K1 is higher with 50% than that of the initial strain after 24 h cultivation, and the highest enzyme activity of T. lactis K1 appears 6h earlier than that of the initial strain. After 24 h cultivation and succeeding 24 h incubation with ibuprofen ethyl ester, the S-ibuprofen production of T. lactis K1 is 6.96 g/L, 64.2% higher than that of T. lactis T, which only produces 4.24 g/L S-ibuprofen at the same time, the specific rotation and enantiomeric excess (ee%) of the S-ibuprofen produced by two stains, however, are the same, + 54.1 degrees and 98%, respectively.