Formation and properties of starch-palmitic acid complex nanoparticles and their influence on Pickering emulsions.

The starch-palmitic acid complex nanoparticles were prepared by Cyperus esculentus starch with enzymatic hydrolysis for different times and then complexed with palmitic acid. The FACE and 13C CP/MAS NMR analysis showed that there were more amylose molecules formed and complexed with palmitic acid when starch was treated by enzymatic hydrolysis for 4 h. With the enzymatic hydrolysis time increasing from 0 h to 4 h, the mean size of starch-palmitic acid complex nanoparticles increased from 500 ± 38.83 nm to 567.2 ± 22.32 nm, the size distribution became more uniform, and the crystallinity increased from 14.99% to 47.72%. The starch-palmitic acid complex nanoparticles could be used as a kind of stabilizers to stabilize Pickering emulsions. Rheological properties and storage stability of Pickering emulsions indicted that starch-palmitic acid complex nanoparticles can better stabilize. The starch-palmitic acid complex nanoparticles could be used as stabilizer of Pickering emulsion and encapsulation of bioactive compounds.

Effect of pulsed electric field on soybean isoflavone glycosides hydrolysis by ß-glucosidase: Investigation on enzyme characteristics and assisted reaction.

This work aimed to investigate how pulsed electric field (PEF) technology as an alternative to enhance the enzymatic hydrolysis of soybean isoflavone glycosides (SIG). To achieve it, the effect of PEF treatment on the activity, kinetics, thermodynamics and structure of ß-glucosidase (ß-GLU) were evaluated. The parameters for PEF-assisted hydrolysis of soybean isoflavone glycosides were optimized by response surface methodology. The results showed that PEF treatment increased the relative activity and catalytic efficiency of ß-GLU with moderate electric field intensity. Furthermore, PEF treatment induced the secondary and tertiary structural change of ß-GLU, the α-helix content increased by 4.23% and the ß-fold content decreased by 3.70%. The optimum conditions for PEF treatment were established as the highest yield of isoflavone aglycones achieved 94.58%. Therefore, these results indicated that PEF treatment could be used as an efficient process to improve the ß-GLU properties, converting soybean isoflavone glycoside to their aglycones form.

Lactoferrin-thymol complex for the disinfection of gram-positive Staphylococcus aureus and Gram-negative Escherichia coli.

Seeking all-nature derived antibacterial agents with effective disinfection function, high human safety as well as environment-friendly characteristics are highly required in the food industry. Herein, we report the lactoferrin-thymol (LF-Thy) complex as an effective killing agent against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). The multi-spectroscopy results clearly demonstrate the combination of LF and Thy to form the LF-Thy complex, accompanied with LF conformation variations including the increase in the hydrophobicity of amino acid residues and changes in the types of secondary conformation distribution in LF. Molecular docking results show that LF exhibits three possible binding sites and five predicted stable binding modes for Thy with the help of hydrogen bonding and hydrophobic interactions. Moreover, LF-Thy demonstrated a significantly higher antibacterial ability compared to LF and displays effective disinfection function against E. coli and S. aureus. The minimum inhibitory concentration (MIC) of LF toward E. coli and S. aureus is >40 mg mL-1 and 40 mg mL-1, which decreases to 10 mg mL-1 and 5 mg mL-1 after combination with Thy, respectively. This work demonstrates the promising antibacterial activities of the LF-Thy complex and provides an alternative agent for combating bacterial infection in the food industry, which holds great potential for promoting the development of the all-natural healthcare food complex.

BRG1 Promotes chromatin remodeling around DNA damage sites.

Chromatin remodeling complexes play important roles in various DNA metabolism processes, including DNA damage repair. BRG1 is the core subunit of the SWI/SNF complex, which plays critical roles in cell cycle regulation, cell development, cell differentiation, and tumorigenesis. In the present study, we report that BRG1 depletion increased the percentage of apoptotic cells in etoposide-treated cells. Moreover, western blotting and immunofluorescence data showed that BRG1 depletion decreased H2AX phosphorylation and caused defective phosphorylated histone H2AX (γH2AX) clearance. Furthermore, we found that in both SW13 and U2OS cells, BRG1 expression could increase the sensitivity of genomic DNA to micrococcal nuclease (MNase) and facilitate chromatin relaxation around DNA damage sites. Thus, the results provide evidence that BRG1 plays an important role in early DNA damage repair by remodeling the chromatin structure near DNA damage sites.

[Key Production Process of Nitrous Oxide and Nitrogen Sources in Tuojia River].

The nitrogen (N) pollution of water is a common global problem. To understand the key production process of N2 O and identify the dominant N sources, Tuojia River, a typical agricultural watershed in a subtropical area, was investigated. To analyze the characteristics of dual nitrate isotopes (δ15N-NO3-,δ18O-NO3-) in water, and N isotope (δ15Norg) and carbon-nitrogen ratio (C/N) in sediment organic matter from four reaches(S1-S4), the stable isotopes method was used. The results showed that the sources of nitrate varied significantly among river segments and were affected by agricultural production and human habitation on the land surface. The average δ15N-NO3- in reaches S1, S2, S3, and S4 were 1.72‰, 2.62‰, 4.10‰, and -1.28‰, respectively, while the average δ18O-NO3- were 2.60‰,-0.06‰, 0.85‰, and -0.62‰. The N in terrestrial soil made a large contribution to nitrate sources in reach S1, while soil N, ammonium N fertilizer, and manure played a main role in reaches S2 and S3. Most of the nitrate came from ammonium N fertilizer in reach S4. We also found that δ15Norg in sediment organic matter ranged from -0.69‰ to 11.21‰, and C/N was between 7.30 and 12.02. The mean δ15Norg in reaches S1-S4 were 1.91‰, 2.96‰, 4.72‰, and 3.23‰, respectively, and the mean C/N values were 10.62, 8.63, 9.05, and 9.22, respectively. Although there were some differences in δ15Norg among reaches S2-S4, the dominant N source was sewage in those reaches. However, soil organic matter was the main N source in the sediments of reach S1. The mean δ18O-NO3- in reaches S1-S4 were -7.01‰,-0.17‰,-0.28‰, and -0.60‰, respectively, indicating that nitrification was the key N2 O production process in these reaches. The ratios of δ15N-NO3- and δ18O-NO3- were 0.66,-41.01,-30.23, and 9.39 in reaches S1-S4, respectively. Finally, we found that there was a positive correlation between NO3--N and δ15N-NO3-. To summarize, the N transformation and N2 O production could be dominated by the nitrification process in Tuojia River.

Hg(II) sensing platforms with improved photostability: The combination of rhodamine derived chemosensors and up-conversion nanocrystals.

This paper reported two nanocomposite sensing platforms for Hg(II) detection with improved photostability, using two rhodamine derivatives as chemosensors and up-conversion nanocrystals as excitation host, respectively. There existed a secondary energy transfer from this excitation host to these chemosensors, which was confirmed by spectral analysis, energy transfer radius calculation and emission decay lifetime comparison. In this case, chemosensor photostability was greatly improved. Further analysis suggested that these chemosensors recognized Hg(II) following a simple binding stoichiometry of 1:1. Hg(II) sensing performance of these sensing platforms was analyzed through their emission spectra upon various Hg(II) concentrations. Emission spectral response, Stern-Volmer equation, emission stability and sensing selectivity were discussed in detail. It was finally concluded that these chemosensors showed emission turn on effect towards Hg(II), with high photostability, good selectivity and linear response.

Huatuo Zaizao pill promotes functional recovery and neurogenesis after cerebral ischemia-reperfusion in rats.

BACKGROUND: Ischemic stroke is the third leading cause of death in adults worldwide and is the first leading cause of long-term disability. Neurogenesis plays an important role in promoting behavioral recovery after stroke. Huatuo Zaizao pill (HT), a traditional Chinese medicine, has been used clinically in China to promote the rehabilitation after stroke, but the underlying mechanism of action was still unclear. This study is to investigate the effects of HT on the functional recovery in a rat model of cerebral ischemia-reperfusion (I/R) injury, and the potential molecular mechanisms. METHODS: Rats were randomly divided into sham, model with cerebral I/R injury, or HT-treated groups, then administered orally with vehicle (for the sham and model group) or HT (0.5, 1.0, or 2.0 mg/kg) respectively, for 3 or 7 days. Functional recovery was assessed by cylinder test, beam walking test, and adhesive test. Neurogenesis was investigated by double immunofluorescence staining for 5-ethynyl-2-deoxyuridine (EdU) and neuronal nuclear protein (NeuN). The proteins of kinase A (PKA), cAMP response element-binding protein (CREB), and brain-derived neurotrophic factor (BDNF) were assayed by western blotting. The level of BDNF mRNA was evaluated by RT-PCR. RESULTS: Compared with the model group, treatment with HT significantly promoted functional recovery in I/R injured rats (p < 0.05 or p < 0.01). The generation of new neurons was increased in the HT groups. HT treatment for 3 days increased the level of BDNF mRNA in I/R injured rats. Expression of PKA, phosphorylated CREB, and BDNF were significantly (p < 0.05) increased with the 7-day HT treatment. CONCLUSIONS: These results indicated that HT treatment could promote functional recovery after stroke. HT enhanced the expression of BDNF and increased the level of neurogenesis in cerebral I/R animal, which might be associated with the functional recovery.

Acetylcholinesterase Inhibitors for Alzheimer's Disease Treatment Ameliorate Acetaminophen-Induced Liver Injury in Mice via Central Cholinergic System Regulation.

Acetaminophen (APAP) is widely used as an analgesic and antipyretic agent, but it may induce acute liver injury at high doses. Alzheimer's disease patients, while treated with acetylcholinesterase inhibitor (AChEI), may take APAP when they suffer from cold or pain. It is generally recognized that inhibiting acetylcholinesterase activity may also result in liver injury. To clarify whether AChEI could deteriorate or attenuate APAP hepatotoxicity, the effects of AChEI on APAP hepatotoxicity were investigated. Male C57BL/6J mice were administrated with the muscarinic acetylcholine receptor (mAChR) blocker atropine (Atr), or classic α7 nicotine acetylcholine receptor (α7nAChR) antagonist methyllycaconitine (MLA) 1 hour before administration of AChEIs-donepezil (4 mg/kg), rivastigmine (2 mg/kg), huperzine A (0.2 mg/kg), or neostigmine (0.15 mg/kg)-followed by APAP (300 mg/kg). Eight hours later, the mice were euthanized for histopathologic examination and biochemical assay. The results demonstrated that the tested AChEIs, excluding neostigmine, could attenuate APAP-induced liver injury, accompanied by reduced reactive oxygen species formation, adenosine triphosphate and cytochrome C loss, c-Jun N-terminal kinase 2 (JNK2) phosphorylation, and cytokines. However, Atr or MLA significantly weakened the protective effect of AChEI by affecting mitochondrial function or JNK2 phosphorylation and inflammation response. These results suggest that central mAChR and α7nAChR, which are activated by accumulated acetylcholine resulting from AChEI, were responsible for the protective effect of AChEIs on APAP-induced liver injury. This indicates that Alzheimer's patients treated with AChEI could take APAP, as AChEI is unlikely to deteriorate the hepatotoxicity of APAP.

Oral Administration of Escin Inhibits Acute Inflammation and Reduces Intestinal Mucosal Injury in Animal Models.

The present study aimed to investigate the effects of oral administration of escin on acute inflammation and intestinal mucosal injury in animal models. The effects of escin on carrageenan-induced paw edema in a rat model of acute inflammation, cecal ligation and puncture (CLP) induced intestinal mucosal injury in a mouse model, were observed. It was shown that oral administration of escin inhibits carrageenan-induced paw edema and decreases the production of prostaglandin E2 (PGE2) and cyclooxygenase- (COX-) 2. In CLP model, low dose of escin ameliorates endotoxin induced liver injury and intestinal mucosal injury and increases the expression of tight junction protein claudin-5 in mice. These findings suggest that escin effectively inhibits acute inflammation and reduces intestinal mucosal injury in animal models.

Yanshu spraying agent, a traditional Chinese medicine, relieves chronic pharyngitis in animals by anti-inflammatory and antibacterial effects.

Chronic pharyngitis is chronic inflammation that is often caused by repeated occurrences of acute pharyngitis or upper respiratory tract infections, including Streptococcus and Staphylococcus. The present study aimed to investigate the effects of Yanshu spraying agent (Yanshu) in relieving chronic pharyngitis, as well as the possible underlying mechanisms. The results revealed that Yanshu inhibited chronic inflammation in ammonia-induced chronic pharyngitis in rabbits and cotton pellet-induced granuloma tissue formation in rats. Yanshu also demonstrated antibacterial effects on Streptococcus and Staphylococcus in vitro. Yanshu did not exhibit any effects on the immune system, including the spleen and thymus indexes, immunocyte count and monocyte-macrophage function, when compared with the effects of dexamethasone. Therefore, the results of the present study indicate that Yanshu may relieve chronic pharyngitis via its anti-inflammatory and antibacterial activities.

The effects of huperzine A on gastrointestinal acetylcholinesterase activity and motility after single and multiple dosing in mice.

The acetylcholinesterase inhibitor (AChEI), huperzine A has been used in the treatment of the cognitive deterioration associated with Alzheimer's disease (AD). However, the side-effects of huperzine A associated with increased cholinergic activity, particularly in the gastrointestinal system, are evident. It is not yet known how quickly these side-effects become tolerated; this information would provide guidance to doctors on how to use huperzine A so as to attenuate the adverse events. The present study aimed to observe the effects of huperzine A on gastrointestinal motility and acetylcholinesterase (AChE) activity in mice. After oral administration of huperzine A with single and multiple dosing, the gastrointestinal motility and AChE activity of the mice were examined. The results revealed that, following a single dose of huperzine A, the AChE activity in the stomach and duodenum were significantly inhibited and the gastrointestinal motility was significantly increased. However, following multiple doses (7 or 28 doses, one dose per day), no significant changes in the AChE activity and gastrointestinal motility were identified. These findings indicate that the gastrointestinal adverse effects of huperzine A may be well-tolerated relatively quickly and do not recur. Additionally, it suggests that patients with AD are likely to have minimal gastrointestinal side-effects after taking multiple doses of huperzine A.

Anti-inflammatory activity of Yanshu spraying agent in animal models.

Acute pharyngitis is characterized by an inflammation of the mucous membranes in the pharynx. Yanshu spraying agent was prepared according to the traditional Chinese formulation for the treatment of acute pharyngitis. The present study aimed to investigate the anti-inflammatory effect of Yanshu in xylene-induced ear edema in mice and carrageenan-induced paw edema in rats by measuring the degree of edema in the animal models. The histopathology and the levels of prostaglandin E2 (PGE2) and cycloxygenase-2 (COX-2) in the hind paws of the carrageenan-treated rats were also analyzed. The results showed that Yanshu significantly reduced ear edema in the mice and paw edema in the rats. Furthermore, treatment with Yanshu also reduced the number of inflammatory cells in tissue and decreased the production of PGE2 and COX-2. These results suggest that Yanshu possesses potent anti-inflammatory activity mediated by the inhibition of COX-2 expression which, in turn, downregulates the inflammatory mediator PGE2.

Conserved miRNAs and their targets identified in lettuce (Lactuca) by EST analysis.

MicroRNAs (miRNAs) are a newly identified class of endogenous, non-coding, short ( approximately 21nt) RNAs that play important roles in regulating gene expression at post-transcriptional level by targeting mRNA cleavage or translational inhibition in plants and animals. Though there are lots of differences between plant miRNAs and animal miRNAs, most of these tiny RNAs are highly conserved in each kingdom. Here, we show the conserved miRNAs in lettuce (Lactuca) identified using EST (expressed sequence tag) analysis. Namely, all previously known miRNAs in other plant species were blasted against lettuce EST sequences to select novel miRNAs in lettuce by a series of filtering criteria. By this strategy, we found a total of 21 conserved miRNAs belonging to 12 miRNA families. After analyzing the conservation and evolution of lettuce miRNAs and their counterparts in other plant species, we revealed that though miRNAs are highly conserved, some specific sites are more likely to mutate. To confirm the expression of identified miRNAs in lettuce, an RT-PCR approach was employed. Moreover, all identified lettuce miRNAs were used to search their potential target genes by miRU web-server from TIGR database available at http://www.tigr.org and a total of 63 potential targets for 10 identified miRNA families in lettuce were found. Similar to previous works, some miRNA targets are transcription factors involved in lettuce growth and development, metabolism, and stress responses.

Computational identification of microRNAs and their targets in wheat (Triticum aestivum L.).

microRNAs (miRNAs) are a class of endogenous, non-coding, short (approximately 21 nt) RNAs directly involved in regulating gene expression at the post-transcriptional level. Previous reports have noted that plant miRNAs in the plant kingdom are highly conserved, which provides the foundation for identification of conserved miRNAs in other plant species through homology alignment. Conserved miRNAs in wheat are identified using EST (Expressed Sequence Tags) and GSS analysis. All previously known miRNAs in other plant species were blasted against wheat EST and GSS sequences to select novel miRNAs in wheat by a series of filtering criteria. From a total of 37 conserved miRNAs belonging to 18 miRNA families 10 conserved miRNAs comprising 4 families were reported in wheat. MiR395 is found to be a special family, because three members belonging to the same miR395 family are clustered together, similar to animal miRNAs. MiRNA targets are transcription factors involved in wheat growth and development, metabolism,and stress responses.

Lycopene accumulation affects the biosynthesis of some carotenoid-related volatiles independent of ethylene in tomato.

For elucidating the regulatory mechanism of ethylene on carotenoid-related volatiles (open chain) compounds and the relationship between lycopene and carotenoid-related volatiles, transgenic tomato fruits in which ACC synthase was suppressed were used. The transgenic tomato fruit showed a significant reduction of lycopene and aroma volatiles with low ethylene production. 6-Methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol and geranylacetone, which were suspected to be lycopene degradation products, were lower than those in wild type tomato fruits. In order to identify whether lycopene accumulation effects the biosynthesis of some carotenoid-related volatiles independent of ethylene in tomato or not, the capability of both wild type and transgenic tomato fruits discs to convert lycopene into carotenoid-related volatiles was evaluated. The data showed that external lycopene could convert into 6-methyl-5-hepten-2-one and 6-methyl-5-hepten-2-ol in vivo, indicating that the strong inhibition of ethylene production had no effect on enzymes in the biosynthesis pathway of some carotenoid-related volatiles. Therefore, in ACS-suppression transgenic tomato fruits, the low levels of 6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol was due to decreased lycopene accumulation, not ethylene production. Ethylene only affected the accumulation of lycopene, and then indirectly influenced the level of lycopene-related volatiles.

[Soil organic carbon storage and its spatial distribution characteristics in Hainan Island: a study based on HNSOTER].

The study based on HNSOTER and supported by GIS showed that in Hainan Island, the total amount of soil organic carbon in the standard profile depth of 0 - 100 cm was about 2.78 x 10(8) t, and the soil organic carbon density in 0 - 20 cm and 0 - 100 cm profile depth was 0.3 - 18.8 kg x m(-2) and 1.0 - 32.1 kg x m(-2), with an area-weighted means of 3.3 kg x m(-2) and 8.4 kg x m(-2), respectively. Soil organic carbon density varied significantly with different landform, lithology and soil, which tended to decrease from the mountains in the middle part of Hainan Island to its coastal plain, and had some differences between 0 - 20 cm and 0 - 100 cm profile depth. The areas of high soil organic carbon density in 0 - 20 cm profile depth were mainly distributed in the mountains and northern basalt tableland, while those in 0 - 100 cm profile depth were in the middle-eastern mountains and tableland. The distribution center of soil organic carbon density in 0 - 100 cm profile depth had a significant shift to the eastern part, compared with that in 0 - 20 cm profile depth.