改进测定饮料中合成色素的方法

改进测定饮料中合成色素的方法四川省产品质量监督检验所周晓群随着科学，尤其是毒理学的发展，人们已发现某些合成色素有慢性毒性和致癌性，因此，各国都严格控制其使用范围和使用量，着色剂指标已成为饮料类产品质量检验的强制性必测项目之一。目前，对于色素的检测方法...

Growth and pigmentation of halophilic archaea Haloarcula isolated from saltponds

Carotenoids accumulation in red halophilic archaea cells is considered apotential biotechnological product possessing a number of biological functions. Anarchaeal strain was isolated from brine water in a saltern crystallizer pond ofHanguSaltworks, China. 16S rRNA gene sequence analysis showed that it wasHaloarcula belonged to extremely halophilic archaea genus Halobacteriaceae. Todeterminethe effect of carbon source on the growth in Haloarcula cells, sucrose,lactose, glucose and soluble starch were supplemented into the culturemediumcontainingdissolved yeast extract and casein hydrolysate （10 g/L, 4：3 w/w） at alevel of 10 g/L, respectively, and sucrose was found to be a suitable one. To determinethe optimal supplementing levels of sucrose, three levels of sucrose （5, 10, 15 g/L）were added to the modified complete medium, and 10 g/L of sucrose supplementationwas optimal. The analysis of TLC and column gel chromatograph on pigment extractshowed five major pigments accumulated in Haloarcula cells, which werepreliminary detected as lycopene, bacterioruberin and its derivatives according to their absorptionpeak features.

Complete genome sequence of the rifamycin SV-producing Amycolatopsis mediterranei U32 revealed its genetic characteristics in phylogeny and metabolism

Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strain U32 comprising 10 236 715 base pairs, is one of the largest prokaryotic genomes ever sequenced so far. Unlike the linear topology found in streptomycetes, this chromosome is circular, particularly similar to that of Saccharopolyspora erythraea and Nocardia farcinica, representing their close relationship in phylogeny and taxonomy. Although the predicted 9 228 protein-coding genes in the A. mediterranei genome shared the greatest number of orthologs with those of S. erythraea, it was unexpectedly followed by Streptomyces coelicolor rather than N. farcinica, indicating the distinct metabolic characteristics evolved via adaptation to diverse ecological niches. Besides a core region analogous to that common in streptomycetes, a novel ＇quasicore＇ with typical core characteristics is defined within the non-core region, where 21 out of the total 26 gene clusters for secondary metabolite production are located. The rifamycin biosynthesis gene cluster located in the core encodes a cytochrome P450 enzyme essential for the conversion of rifamycin SV to B, revealed by comparing to the highly homologous cluster of the rifamycin B-producing strain S699 and further confirmed by genetic complementation. The genomic information of A. mediterranei demonstrates a metabolic network orchestrated not only for extensive utilization of various carbon sources and inorganic nitrogen compounds but also for effective funneling of metabolic intermediates into the secondary antibiotic synthesis process under the control of a seemingly complex regulatory mechanism.

Distribution and ultrastructure of pigment cells in the skins of normal and albino adult turbot, Scophthalmus Maximus

The distribution and ultrastructure of pigment cells in skins of normal and albino adult turbots were examined with transmission electron microscopy （TEM）. Three types of pigment cells of melanophore, iridophore and xanthophore have been recognized in adult turbot skins. The skin color depends mainly on the amount and distribution of melanophore and iridophore, as xanthophore is quite rare. No pigment cells can be found in the epidermis of the skins. In the pigmented ocular skin of the turbot, melanophore and iridophore are usually co-localized in the dermis. This is quite different from the distribution in larvae skin. In albino and white blind skins of adult turbots, however, only iridophore monolayer still exists, while the melanophore monolayer disappears. This cytological evidence explains why the albino adult turbot, unlike its larvae, could never resume its body color no matter what enviroumental and nutritional conditions were provided. Endocytosis is quite active in the cellular membrane of the iridophore. This might be related to the formation of reflective platelet and stability of the iridophore.

Tribological characteristics and self-repairing effect of hydroxy-magnesium silicate on various surface roughness friction pairs

Tribological characteristics and self-repairing effect of hydroxy-magnesium silicate (HMS) dispersed in lubricant oil on steel-to-steel friction pairs with various surface roughness were analyzed.The friction-reduction,anti-wear and self-repairing performance of various surface roughness friction pairs were examined by friction testing machine.An operation comparison was made between SJ10W-40 lubricant with and without HMS.The surface morphology and elementary composition of the grinding cracks were analyzed by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS).The results show that the lubrication state changes from boundary lubrication into mixed lubrication after operation in lubricant with HMS.The friction-reduction,anti-wear and self-repairing performance of the friction pairs with various surface roughness are distinctly different.There is a repairing film whose material is different from substrate material on the grinding cracks.In addition,Si,Mg,O,Al and other elements are deposited on the repairing film which contains nanocrystals of these elements.And HMS self-repairing material possesses superior performance of friction-reduction,anti-wear and self-repairing effects.

Phytoplankton pigment patterns and community composition in the northern South China Sea during winter

Phytoplankton pigment patterns and community composition were investigated in the northern South China Sea using high-performance liquid chromatography and the CHEMTAX software from February 11 to 23, 2009. We recognized four different vertical distribution patterns of pigments: chlorophyll a (Chl a)-like type, divinyl chlorophyll a (DV Chl a) type, even distribution type, and surface type. The average value of ratios of accessory photo-protective pigments (APP) to accessory photo-synthetic pigments was 0.89±0.63 in the upper 50 m and 0.16±0.06 below 50 m depth. With increasing depth, APP decreased and photo-synthetically active radiation was attenuated. There was an obvious succession in the phytoplankton community from inshore to the open sea. Diatoms were dominant in the inshore region, while pelagophytes, Prochlorococcus, cyanobacteria and prymnesiophytes were dominant in the open sea. The vertical distribution of phytoplankton also differed greatly from inshore to the open sea. In the coastal and shelf region, diatoms were important components in the whole water column. Cyanobacteria also had a high abundance at the Subsurface Chlorophyll a Maxima (SCM) in the shelf region. In the slope and open sea, Prochlorococcus and cyanobacteria were important groups above the SCM, while pelagophytes dominated below the SCM.

Regulation of Anthocyanin during Storage Root Development Stage in Sweet Potato(Ipomoea batatas(L.) Lam.)

Anthocyanin accumulation during storage root development in purple-fleshed sweet potato was analyzed by detection of anthocyanin concentration, accumulation rate and the expression pattern of anthocyanin biosynthetic genes by semi-quantitative RT-PCR. Anthocyanin concentration in sweet potato cvs Jishu 18 and Ayamurasaki increased steadily during storage root development stage. The accumulation rate in two genotypes peaked at 50 to 65 d after transplanting, and then declined rapidly. During storage root development of Ayamurasaki, the anthocyanin biosynthesis gene, IbCHS, was constitutively expressed, the genes IbF3H, IbDFR, IbANS were induced steadily, reaching a maximum at the later stage of root thickening, and IbPAL steadily decreased. Therefore, the mechanism of anthocyanin accumulation differed between the two cultivars, and anthocyanin biosynthesis was regulated through regulation of its synthetic enzymes.

Venlafaxine Dependence： A Case Report

Venlafaxine, an SNRI （serotonin-norepinephrine reuptake inhibitor） drug, is commonly used to treat depression. Although it is very rare, venlafaxine may lead to addiction or abuse in some patients. To date, there are very limited data available on venlafaxine addiction. The aim of this article is to draw an attention to dependence of venlafaxine in clinical practice. Significant point of this article is： Our patient was addicted by ＂high＂ doses of venlafaxine for getting high effects. Overdose of venlafaxine produces an amphethamine-like ＂high＂ with experiences of euphoria by its ability to increase neurotransmitter levels in addiction literature [1-3]. We present a man aged 42 years, who was referred to our clinic for detoxification from venlafaxine addiction. He had been taking venlafaxine upto 1,950-2,100 mg/day to get high for the past 10 years. Physicians must be careful when prescribing antidepressants to patients, especially those with a history of alcohol and/or drug addictions or abuse.

Component Analysis of Volatile Oil of Garlic from Different Districts and Assay of Allicin Content

[ Objective] The aim was to study the chemical component of volatile oil of garlic in different districts. [ Method] GC-MS was used to an- alyze the composition of the garlic volatile oil in Guiyang, Guizhou Majiang, Shandong, Yunnan and Chongqing and the HPLC method was used to assay the content of gadicin. [ Result]Gadicin in different essential oil had the highest content but varied a lot. The sampling amount of garlicin be- tween 0.562 and 2.810 μg was in a good linear relation （R =0.999 2, n = 5 ） with peak area, the average recovery rate was 99.39, RSD = 1.76%. [ Conclusion] GC-MS can be used to analysis the composition of essential oil quickly and effectively. The liquid chromatographic analysis of garlicin was simple, reliable and reproducible. The study provided the theoretical basis for selecting garlic in gadic flavor oil production and improving quality of gadicin oil.

Study on the Element Composition of Southern Celadon Porcelain and Coloring Mechanism

This paper mainly discusses the Si/Al molar ratio, RO/R2O molar ratio, Fe content, glazing and firing system on the thickness of Longquan Celadon pink coloring effects, and using a colorimeter, field emission scanning electron microscopy were used to analyze better experimental sample microstructure and color and so on. We explored the Longquan Celadon of pink coloration mechanism.

Study on the Element Composition of Southern Celadon Porcelain and Coloring Mechanism

This paper mainly discusses the Si/A1 molar ratio, RO/R20 molar ratio, Fe content, glazing and firing system on the thickness of Longquan Celadon pink coloring effects, and using a colorimeter, field emission scanning electron microscopy were used to analyze better experimental sample microstructure and color and so on. We explored the Longquan Celadon of pink coloration mechanism.

The Lack of Afterlife and Its Effects on Chinese Economic Behavior

It is widely recognized that each culture has a specific effect on the economic development. Based on Chinese culture which can be characterized as lack of afterlife, the pattern of Chinese economic development has distinctive features relative to the economy of the Western world, even to that of Japan and Korea. This paper argues that culture influences economic development through two paths： One is that some cultural factors, as certain institutions, have effects on cost, especially transaction costs. Another point is that culture forms people＇s preferences and influences people＇s choices. With the influences of Chinese culture, Chinese have a weak sense for legal obedience and strong inclination for ＂free riding＂, this would increase social transaction costs. The family centered tradition of Chinese society results in Chinese features such as being good at individual struggles but poor at cooperation, the alienation between civil society and government, a strong sense for competition and a weak sense for legal obedience, seeing material wealth as important and neglecting scientific innovation. Traditional Chinese culture also has effects on the developmental pattern of Chinese enterprises

Facilitated column selection in the separation of acetylspiramycin components using a simple column classification system

Acetylspiramycin（ASPM）,a 16-membered basic macrolide antibiotic,is the acetylated derivative of spiramycin.In addition to the four main components,more than seventy minor components could be present in ASPM.Thus,it is a challenge to obtain a baseline separation of ASPM components.Meanwhile,in some cases it was found that the results obtained by different brands of C_（18） columns were significantly different,indicating the necessity of a rational column selection for the separation of ASPM components.In this paper,we attempted to facilitate column selection for the analysis of ASPM using the database of the column characterization system established by Leuven University.With the CAPCELL PAK MG C_（18）（250 mm×4.6 mm,5μm） as the reference column,three groups of columns（F2 group：similar selectivity;2F6：intermediate ranked group;F6 group： different selectivity,compared to the reference column） were selected,and their performances in the separation of ASPM components were evaluated under the chromatographic conditions described in Chinese Pharmacopoeia monograph.A good relationship was demonstrated between the ranking of columns and their selectivity in the separation of ASPM components,indicating the column classification system established by Leuven University was a helpful tool in the selection of suitable columns for the analysis of ASPM,a complex mixture of basic compounds.

Role of endoscopy in inflammatory bowel disease

Crohn’s disease(CD)and ulcerative colitis(UC)constitute the twomost common phenotypes of inflammatory bowel disease(IBD).Ileocolonoscopy with biopsy has been considered the gold standard for the diagnosis of IBD.Differential diagnosis of CD and UC is important,as theirmedical and surgical treatmentmodalities and prognoses can be different.However,approximately 15%of patients with IBD aremisdiagnosed as IBD unclassified due to the lack of diagnostic certainty of CD or UC.Recently,there has been increased recognition of the role of the therapeutic endoscopist in the field of IBD.Newer imaging techniques have been developed to aid in the differentiation of UC vs CD.Furthermore,endoscopic balloon dilation and stenting have become an integral part of the therapeutic armamentariumof CD stricturemanagement.Endoscopic ultrasound has been recognized as beingmore accurate thanmagnetic resonance imaging in detecting perianal fistulae in patientswith CD.Additionally,chromoendoscopymay help to detect dysplasia earlier compared with white-light colonoscopy.Hence,interventional endoscopy has become a cornerstone in the diagnosis,treatment andmanagement of IBD complications.The role of endoscopy in the field of IBD has significantly evolved in recent years fromsmall-bowel imaging to endoscopic balloon dilation and use of chormoendoscopy in dysplasia surveillance.In this reviewarticle,we discuss the current evidence on interventional endoscopy in the diagnosis,treatment andmanagement of IBD compications.

A PKS gene, pks-1, is involved in chaetoglobosin biosynthesis, pigmentation and sporulation in Chaetomium globosum

Chaetomium globosum is one of the most common fungi in nature. It is best known for producing chaetoglobosins; however, the molecular basis of chaetoglobosin biosynthesis is poorly understood in this fungus. In this study, we utilized RNA inter- ference （RNAi） to characterize a polyketide synthase gene, pks-1, in C. globosum that is involved in the production of chaeto- globosin A. When pks-1 was knocked down by RNAi, the production of chaetoglobosin A dramatically decreased. Knock-down mutants also displayed a pigment-deficient phenotype. These results suggest that the two polyketides, melanin and chaetoglobosin, are likely to share common biosynthetic steps. Most importantly, we found that pks-I also plays a critical role in sporulation. The silenced mutants ofpks-1 lost the ability to produce spores. We propose that polyketides may modulate cellular development via an unidentified action. We also suggest that C. globosum pks-1 is unique because of its triple role in melanin formation, chaetoglobosin biosynthesis and sporulation. This work may shed light on chaetoglobosin biosynthesis and indicates a relationship between secondary metabolism and fungal morphogenesis.

Overexpression of the bacterial tryptophan oxidase RebO affects auxin biosynthesis and Arabidopsis development

Both tryptophan （Trp） and auxin are essential for plant growth and Trp is a precursor for auxin biosynthesis. Concentrations of Trp and auxin need to be tightly con- trolled to ensure optimal growth and development. It has been very difficult to study the homeostasis of these two essential and inter-dependent compounds. Auxin is mainly synthesized from Trp via a two-step pathway using indole- 3-pyruvate （IPA） as the intermediate. Here we used a bacterial Trp oxidase RebO, which does not exist in Ara- bidopsis and which converts Trp to the imine form of IPA, to modulate IPA levels in Arabidopsis. Our results demonstrate that Arabidopsis plants use two strategies to ensure that no excess IPA is made from Trp. IPA is made from Trp by the TAA family of aminotransferases, which we show catalyzes the reverse reaction when IPA level is high. Moreover, excess IPA is converted back to Trp by the YAS1 aminotransferase. We show that the VASl-cat- alyzed reaction is very important for Trp homeostasis. This work not only elucidates the intricate biochemical mech- anisms that control the homeostasis of Trp, IPA, and auxin, but also provides novel tools for further biochemical studies on Tip metabolism and auxin biosynthesis in plants.