Bioactive constituents, nutritional benefits and woody food applications of Castanea mollissima: A comprehensive review.

Castanea mollissima BL. is an outstanding species that represents a valuable woody food resource due to consumers' salient beliefs in the health benefits of chestnut consumption. Besides chestnut kernel, the discarded shells of chestnut were highlighted as remarkable sources of functional ingredients with promising applications in food, nutraceutical, pharmaceutical and industrial raw materials, mainly as natural antioxidants and effective prebiotics. Phytochemical studies reported not only antioxidant and antimicrobial activities, but also anti-inflammatory, anticancer, hypolipidemic, hypoglycemic and neuroprotective activities. This review aims to summarize the botanical characteristics, nutritional compositions, biological activities and comprehensive utilization of the whole C. mollissima, emphasizing the value of sustainable use in the recovery of bioactive compounds and their potential applications in food and other industries. It will provide a reference for the further development of C. mollissima in the field of multi-functional food and will inspiring investigations on the comprehensive utilization of chestnut and their by-products.

Breeding of a thermostable xylanase-producing strain of Myceliophthora thermophila by atmospheric room temperature plasma (ARTP) mutagenesis.

Introduction: Hemicellulose is an important component in lignocellulose materials, which is second only to cellulose, accounting for 15%-35% of the dry weight of plants. In the current situation of energy shortage, making full use of lignocellulose materials to produce fuel ethanol has become an important way to solve the energy problem. Xylanase plays a crucial role in the utilization of hemicellulose. It is a necessary means to reduce the cost of hemicellulose utilization by improving the activity of xylanase. Moreover, most naturally xylanases are mesophilic enzymes, which limits their industrial application. Methods:In this study, Myceliophthora thermophila was used to produce xylanases and a thermostable mutant M 2103 was obtained by atmospheric room temperature plasma (ARTP) mutagenesis. The research work started with exploring the effects of ARTP mutagenesis on the antioxidase system [superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO), and antioxidant capacity (AOC)] of M. thermophile, and found that superoxide dismutase activity increased by 221.13%, and polyphenol oxidase activity increased by 486.04% as compared with the original strain when the implantation time was 300 s. So as to determine the conditions for subsequent mutagenesis. Results and Discussion:For the mutant M 2103, the reaction temperature for xylanase production remained stable in the range of 70°C-85°C. Its optimum temperature was 75°C, which was 15°C higher than that of the original strain. And its xylanase activity increased by 21.71% as compared with the original strain. M 2103 displayed a significantly higher relative xylanase activity than the original strain in the acidic (pH 4.0-7.0) range, and the xylanase activity was relatively stable in the pH range of 6.0-8.5. These results provide an alternative biocatalyst for the production of xylooligosaccharide, and a potential usage of ARTP in the mutagenesis of thermostable mutant.

Effects of Microwave-Assisted Liquid Hot Water Pretreatment on Chemical Composition and Structure of Moso Bamboo.

The effects of microwave assisted liquid hot water (MA-LHW) pretreatment on the chemical composition of Moso bamboo were investigated, and the fiber structure of pretreated residues were studied. The results showed that MA-LHW pretreatment had high selectivity for the degradation of hemicellulose in Moso bamboo, and the extracted hemicellulose could be used to prepare xylooligosaccharide through enzyme depolymerization. The degradation rates of cellulose and lignin after MA-LHW pretreatment were only 14.73% and 7.18%, which were significantly lower than those of LHW pretreatment; 155.0 mg/g xylobiose and 61.0 mg/g xylotrisoe can be obtained after enzymatic hydrolysis, and the yield of xylo-oligosaccharide reached 80.59% of the theoretical conversion rate. MA-LHW pretreatment increased the removal of hemicellulose, lignin, and other non-crystalline parts in bamboo materials, and more cellulose with crystalline structure was retained, which increased the CrI value of Moso bamboo by 14.84%. FTIR spectra showed that the characteristic peak intensity of hemicellulose was significantly reduced after MA-LHW pretreatment, which confirmed the selective degradation of hemicellulose by MA-LAW pretreatment. Moreover, MA-LHW pretreatment also destroyed O-H, C-H, C-O-C, and ß-glucoside bonds in Moso bamboo fiber, caused by the recombination and synthesis of some groups (-CH2 and C=O) of cellulose, hemicellulose, and lignin destroyed under pretreatment conditions.

Effects of Liquid Hot Water Combined with 1, 4-Butanediol on Chemical Composition and Structure of Moso Bamboo.

The effects of liquid hot water combined with 1, 4-butanediol (LHW-BDO) on the chemical composition and structure of moso bamboo were investigated. The structure changes of moso bamboo fibers were characterized by infrared spectroscopy, X-ray diffraction, and electronic scanning electron microscopy. The results showed that the delignification rates of 1, 4-butanediol (BDO) and LHW-BDO pretreatment methods were at the same level (91.42-93.08%). However, compared with BDO pretreatment, the cellulose content in solid residue after LHW-BDO pretreatment was increased by 17.06% with a recovery rate of 75.68%, while the hemicellulose removal rate increased by 115.33% and reached 50.34%. After LHW-BDO pretreatment, the intramolecular hydrogen bonds, intermolecular hydrogen bonds, methylene bonds, and aromatic ether bonds of the fibers were broken, which contributed to the depolymerization and separation of cellulose, hemicellulose, and lignin molecules. However, LHW-BDO pretreatment does not destroy the ß-glycoside bond which links the glucose molecule inside the fiber molecule, which was also beneficial to the separation of cellulose. In addition, the amorphous zone of bamboo fibers was destroyed by the above treatments, and the fiber structure of bamboo samples mostly exists in crystalline form. The crystallinity of bamboo pretreated with LHW-BDO was increased by 32.15%. It can be found by scanning electron microscopy that the surface of the pretreated bamboo samples showed uniformly distributed bubbly protuberance.

Citric Acid Production from Acorn Starch by Tannin Tolerance Mutant Aspergillus niger AA120.

In this study, acorn starch was investigated as a new material for fermenting production of citric acid by using a tannin tolerance mutant strain Aspergillus niger AA120. The mutant A. niger AA120 was obtained by initially atmospheric pressure plasma at room temperature (ARTP) mutagenesis and then tannin gradient domestication. ARTP experiments showed that a "double-saddle" shape of survival rate curve was achieved, and a positive mutation rate of 63.6% was reached by setting the implantation time of mutagenesis to 100 s. In contrast to the original stain at the presence of 20.0 g/L tannin in the medium, the selected mutant A. niger AA120 exhibits an increase of biomass by 43.76% to 32.9 g/L, and citric acid production capacity by 20.34% to 130.8 g/L, with 8% (w/w) of inoculation quantity, an initial pH of 6.2 and shaking speed of 250 r/min. In this work, we present a referable method for the mutagenesis screening of the A. niger, and the application of acorn starch as a new raw material for the development of the citric acid industry.

[Adsorption kinetic and thermodynamic studies of lead onto activated carbons from cotton stalk].

Low-cost high surface area microporous carbons were prepared from cotton stalk and cotton stalk fiber by H3PO4 activation. The adsorption of lead ions on the carbons was investigated by conducting a series of batch adsorption experiments. The influence of solution pH value, contact time and temperature was investigated. The adsorption kinetics, thermodynamic behavior and mechanism were also discussed. The surface area and pore structure of the activated carbons were analyzed by BET equation, BJH method and H-K method according to the data from nitrogen adsorption at 77K. Boehm titration, Fourier transform infrared spectroscopy (FTIR), the point of zero charge (pH(PZC)) measurement and elemental analysis were used to characterize the surface properties. The results show that the carbons from cotton stalk and cotton stalk fiber have high surface area of 1570 and 1731 m2 x g(-1), and high content of oxygen-containing functional groups of 1.43 and 0.83 mmol x g(-1). The adsorption experiments show that the carbons have high adsorption capacity for lead, and the maximum adsorption equilibrium amount was found to be 120 mg x g(-1). The adsorption amount increased with contact time, and almost 80% of the adsorption occurred in the first 5 min. The pseudo-second-order model describes the adsorption kinetics most effectively. The Freundlich isotherm was found to the best explanation for experimental data. The negative change in free energy (delta G0) and positive change in enthalpy (delta H0) indicate that the adsorption is a spontaneous and endothermic process, and the adsorption of lead ions onto the carbons might be involved in an ion-exchange mechanism.

[Mechanism of Yiqi Huayu Bushen recipe in treating cervical syndrome in rats with qi deficiency, blood stasis and kidney deficiency].

OBJECTIVE: To explore the mechanism of Yiqi Huayu Bushen Recipe (YHBR), a compound traditional Chinese herbal medicine, in treating cervical syndrome (CS) with qi deficiency, blood stasis and kidney deficiency in rats. METHODS: A total of 30 three-month-old female Sprague-Dawley rats were randomly divided into normal control group, untreated group and YHBR group; there were ten rats in each group. The rat model of cervical syndrome with qi deficiency, blood stasis and kidney deficiency was established by combining disease and syndrome models. After one-month YHBR treatment in YHBR group, all rats were sacrificed. Serum, plasma and cervical intervertebral discs were detected and observed by radio-immunology, histopathology, immunohistochemistry, etc. RESULTS: Compared with those in the normal control group, rats in the untreated group showed obvious signs of deficiency in vital energy, such as tiredness, ptosis, few movement, bluish-purple tongue and tail and weight loss; the weight of uterus and appendages, and the ratio of cyclic adenosine monophosphate/cyclic guanosine monophosphate were decreased; hemorheological parameters and the expression of alpha-granular membrane protein (CD62p) were increased; the content of serum estradiol was decreased. YHBR could improve the above indexes except for the weight of uterus and appendages. HE staining showed annulus fibrosus with cracks, diminish of pulposus nucleus, and decrease in the height of intervertebral disc and the thickness of end-plate in the untreated group; and YHBR could improve the changes of cervical intervertebral discs, but no obvious changes in end-plate. Type II collagen protein (Col2a1)was distributed in every part of the annulus fibrosus in normal control group, but was decreased in untreated group; YHBR could increase Col2a1 expression in annulus fibrosus as compared with the untreated group. The expressions of Col2a1 and tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNAs were decreased in untreated group as compared with the normal control group (P<0.01); the expressions of Col2a1 and TIMP-1 mRNAs were higher and matrix metalloproteinase-13 mRNA was lower in the YHBR group than those in the untreated group (P<0.05, P<0.01). CONCLUSION: YHBR may improve the condition of cervical syndrome with qi deficiency, blood stasis and kidney deficiency by regulating immune system, coagulation system and endocrine system, and delay the degeneration of cervical intervertebral disc by regulating extracellular matrix and metalloproteases in intervertebral disc.

[Mechanism of Yiqi Huayu Bushen Recipe in treating cervical syndrome with kidney deficiency in rats].

OBJECTIVE: To research the action mechanism of Yiqi Huayu Bushen Recipe (YHBR), a compound of traditional Chinese herbal medicine, in treating cervical syndrome (CS) with kidney deficiency in rats. METHODS: A total of 30 three-month-old female Sprague-Dawley rats were randomly divided into normal control group, CS with kidney deficiency model group (untreated group) and YHBR group, with 10 rats in each group. Rats in the normal control group received no treatment, while rats of the other two groups underwent resection of both cervical muscles and ovaries to establish the model of CS with kidney deficiency. Three months after surgery, rats in the YHBR group were intragastrically administered YHBR for one month. Another one month later, all rats were sacrificed. The content of serum estradiol (E2) was detected by radio-immunoassay; contents of plasma cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) were tested, and the ratio of cAMP/cGMP was also calculated. Hemorheology was detected by Weissenberg's method; expression of alpha-granular membrane protein (CD62p) was detected by flow cytometry; HE staining was used to detect the histopathology of cervical intervertebral disc degeneration; type II collagen protein was detected by immunohistochemistry and aggrecan-1 (Agc1), type II procollagen gene, Col2a1, tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metalloproteinase-13 (MMP-13) mRNAs were detected by fluorescent quantization polymerase chain reaction. RESULTS: Compared with the untreated group, rats in the YHBR group showed an obvious increase in serum E2 content (P<0.05), and an increase in plasma cAMP and cGMP content without significant difference; hemorheological parameters and percentage of CD62p expression were significantly decreased in the YHBR group (P<0.05, P<0.01). YHBR could improve the degeneration of cervical intervertebral discs, decrease the Miyamoto scores (P<0.05), and increase the type II collagen. The expressions of Agc1, Col2a1 and TIMP-1 mRNAs were significantly increased and MMP-13 mRNA significantly decreased in YHBR group (P<0.05, P<0.01). CONCLUSION: YHBR may improve CS with kidney deficiency and delay the degeneration of cervical intervertebral disc by regulating the immune-metabolism system, coagulation system and endocrine system.

[Establishment of a rat model of cervical syndrome with qi deficiency, blood stasis and kidney deficiency].

OBJECTIVE: To establish a rat model of cervical syndrome with qi deficiency, blood stasis and kidney deficiency. METHODS: A total of 30 three-month-old female Sprague-Dawley rats were randomly divided into normal group, cervical syndrome group and cervical syndrome with qi deficiency, blood stasis and kidney deficiency group (combined group), with 10 rats in each group. Rats in the normal group received no treatment, rats in cervical syndrome group underwent resection of cervical muscles and ligaments as unbalanced dynamic and static animal model, and rats in combined group underwent resection of both cervical muscles and ovaries, swimming and irregular diet, and injection of adrenal cortex hormone and adrenaline two and a half months after resection as combined model. The qi deficiency, blood stasis and kidney deficiency were determined by observing behaviors and physical signs of the rats, detecting the contents of plasma cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), the hemorrheology, the expression of alpha-granular membrane protein (CD62p) and the serum estradiol (E(2)) content. The aggrecan-1, type II procollagen gene (Col2a1), matrix metalloproteinases-13 (MMP-13) and tissue inhibitor of metalloproteinases-1 (TIMP-1) mRNAs in cervical intervertebral discs were detected by histopathology, immunohistochemistry and real-time polymerase chain reaction. The cataplasia of the intervertebral discs was determined by detecting the histopathology, the expressions of type II collagen and type X collegen proteins, and the expressions of aggrecan-1 (Agc1), type II procollagen gene (Col2a1), matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNAs. RESULTS: Compared with those in the normal group and cervical syndrome group, the rats in the combined group were noted with obvious signs of deficiency of vital energy, such as depression, tiredness, ptosis, obvious weight loss and blue tail. And the ratio of cAMP/cGMP was decreased; the reducing viscosity was significantly up-regulated; the expression of CD62p was increased; the content of serum E(2) was decreased; the intervertebral disc structure was destructed; the cervical intervertebral disc was more seriously deteriorated. There exhibited a decrease in type II collagen protein expression, an increase in type X collagen protein expression, as well as decreases of Agc1, Col2a1 and TIMP-1 mRNA expressions in intervertebral disc, and the expression of MMP-13 mRNA was noted an increase. CONCLUSION: The rat model of cervical syndrome with qi-deficiency, blood stasis and kidney deficiency is established. Qi deficiency, blood stasis and kidney deficiency can aggravate cervical intervertebral disc degeneration.

[Establishment of a rat model of cervical syndrome with kidney deficiency].

OBJECTIVE: To establish a rat model of cervical syndrome (CS) with kidney deficiency. METHODS: A group of 30 three-month-old female Sprague-Dawley rats were randomly divided into normal control group, CS group and CS with kidney deficiency group (combined group), with 10 rats in each group. Rats in the normal control group received no treatment, rats in the CS group underwent only resection of cervical muscles and ligaments as unbalanced dynamic and static animal model, and rats in combined group underwent resection of both cervical muscles and ovaries as kidney deficiency model. Serum and cervical intervertebral discs were collected. Kidney deficiency was determined by observing the morphologic changes of uterus and appendages, detecting the weight of uterus and appendages and the content of serum estradiol (E(2)). The degeneration of intervertebral discs was determined by detecting the histopathology, the expressions of type II collagen and type X collagen proteins, and the expressions of aggrecan-1 (Agc1), type II procollagen gene (Col2a1), matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of metalloproteinases-1 (TIMP-1) mRNAs. RESULTS: Compared with those in the normal control group and CS group, the rats in the combined group were noted with the uterus atrophied, the caliber of oviduct thinned, the weight of uterus and appendages diminished obviously, the content of serum E(2) decreased, cervical intervertebral disc degenerated more seriously, type II collagen protein expression decreased, type X collagen protein expression increased, Agc1 and Col2a1 mRNA expressions in intervertebral disc decreased, and the MMP-13 mRNA expression increased. CONCLUSION: The rat model of CS with kidney deficiency is established. Kidney deficiency can aggravate cervical intervertebral disc degeneration.