As the basic unit of proteins，amino acids play an important role in the nutritional health of people and animals． Currently，the global amino acid industry has developed into a large industrial group with a wide range of varieties and complete categories，becoming one of the pillar fermentation industries． Due to the high demand of amino acids，the world's largest amino acid producers have competitively developed production technologies to secure the supply of amino acids． This paper reviews the demand and price trends of amino acid products，the distribution pattern of amino acid manufacturers and the development of amino acid technology．

The development, characteristics, applications and scale -up of disposable bioreactor were summarized in this review. The wave-mixed, stirred and orbital shaken disposable bioreactors were elaborated. The challenges and future prospects of disposable bioreactor were also discussed.

Ｘａｎｔｈａｎ　ｇｕｍ　ｈａｓ　ｔｈｅ　ｐｒｏｐｅｒｔｉｅｓ　ｏｆ　ｓｈｅａｒ　ｄｉｌｕｔｉｏｎ，ｓｕｓｐｅｎｓｉｏｎ　ｅｍｕｌｓｉｆｉｃａｔｉｏｎ，
ｔｈｉｃｋｅｎｉｎｇ，ｒｅｓｉｓｔａｎｃｅ　ｔｏ　ｓａｌｔ，ａｃｉｄ，ａｌｋａｌｉ　ａｎｄ　ｈｉｇｈ　ｔｅｍｐｅｒａｔｕｒｅ，ｗｈｉｃｈ　ｉｓ　ｗｉｄｅｌｙ　ｕｓｅｄ　ｉｎ
ｐｅｔｒｏｌｅｕｍ　ｅｘｐｌｏｉｔａｔｉｏｎ，ｃｈｅｍｉｃａｌ，ｐｈａｒｍａｃｅｕｔｉｃａｌ，ｆｏｏｄ　ａｎｄ　ｍａｎｙ　ｏｔｈｅｒ　ｉｎｄｕｓｔｒｉｅｓ．Ｔｈｉｓ　ｒｅｖｉｅｗ
ｂｒｉｅｆｌｙ　ｄｅｓｃｒｉｂｅｓ　ｔｈｅ　ｂａｓｉｃ　ｓｔｒｕｃｔｕｒｅ，ｐｒｏｃｅｓｓ，ｐｒｏｐｅｒｔｉｅｓ　ｏｆ　ｘａｎｔｈａｎ　ａｎｄ　ｉｔｓ　ａｐｐｌｉｃａｔｉｏｎ　ｉｎ　ｆｏｏｄ　ａｎｄ
ｃｏｍｐｏｕｎｄ　ｇｕｍｓ，ｅｓｐｅｃｉａｌｌｙ　ｔｈｅ　ａｐｐｌｉｃａｔｉｏｎ　ｏｆ　ｘａｎｔｈａｎ　ｇｕｍ　ｉｎ　ｍｅａｔ　ｐｒｏｄｕｃｔｓ，ｆｌｏｕｒ　ｐｒｏｄｕｃｔｓ　ａｎｄ
ｂｅｖｅｒａｇｅｓ，ａｓ　ｗｅｌｌ　ａｓ　ｉｔｓ　ｃｏｍｐａｔｉｂｉｌｉｔｙ　ｗｉｔｈ　ｃａｒｒａｇｅｅｎａｎ，ｌｏｃｕｓｔ　ｂｅａｎ　ｇｕｍ　ａｎｄ　ｋｏｎｊａｃ　ｇｕｍ．

 

As an important member of the aldo-keto reductase ( AKR) superfamily，microbial AKRs exist in a wide range of microorganisms and perform oxidoreduction on a broad variety of natural and artificial ketone compounds． Usually，microbial AKRs are monomeric proteins with molecular weights around 37 kDa，containing the typical ( α /β)8-barrel fold and a conserved coenzyme binding domain． All microbial AKRs obey the ordered bi-bi mechanism，driven by a tetrad of Asp-Tyr-Lys-His． Currently，microbial AKRs have been applied in the synthesis of xylitol，vitamin C immediate precursor 2-keto-L-gulonic acid and pharmaceutical intermediate chiral alcohols．

 

The separation and purification processes of chlorogenic acid from green coffee beans were studied. On the basis of single-factor experiments, hot water extraction of chlorogenic acid was optimized by response surface methodology. The results showed that the chlorogenic acid yield was significantly affected by the four factors, and the optimum extraction conditions were temperature 79.8 ℃, solvent pH 2.8, solid/liquid ratio 1∶6 and extraction time 3.0 h. The maximum extraction yield of chlorogenic acid was 92.0%. The experiments on screening of different resins showed that XDA-8 resin had best efficiency in chlorogenic acid separation and purification. Under the optimized conditions, chlorogenic acid content and recovery reached 70.9% and 85.4%, respectively. Preparative high performance liquid chromatography was used to obtain high purity (95.2%) of chlorogenic acid from green coffee bean extract. The established preparation process of chlorogenic acid had the advantages of simple, efficient and environmentally friendly

 

 

Based on the L-tryptophan chromatographic separation process which was jointly developed by France Novasep, the process parameters of L-tryptophan chromatographic separation in pilot scale were investigated, and a comparison with the traditional ion exchange process was also made. The results showed that L-tryptophan with a purity of 82%~93% was obtained by using the SSMB optimized process, and the yield reached 99%. Compared to IEX process, SSMB process resulted in higher L-tryptophan purity, less NH4+ content and lower conductivity of extract.

 

Ｏｘｉｄｏｒｅｄｕｃｔａｓｅｓ　ａｒｅ　ａ　ｇｒｏｕｐ　ｏｆ　ｅｎｚｙｍｅｓ　ｗｉｔｈ　ｈｉｇｈ　ｅｆｆｉｃｉｅｎｃｙ　ａｎｄ　ｓｐｅｃｉｆｉｃｉｔｙ　ｉｎ　ｏｘｉｄａｔｉｏｎ ｏｒ　ｒｅｄｕｃｔｉｏｎ　ｒｅａｃｔｉｏｎｓ，ｗｈｉｃｈ　ｈａｖｅ　ｂｅｅｎ　ｗｉｄｅｌｙ　ａｐｐｌｉｅｄ　ｉｎ　ｂｉｏｃａｔａｌｙｓｉｓ　ａｎｄ　ｏｒｇａｎｉｃ　ｓｙｎｔｈｅｓｉｓ．Ｔｈｅ ｍｕｌｔｉ－ｅｎｚｙｍａｔｉｃ　ｃａｓｃａｄｅ　ｒｅａｃｔｉｏｎｓ　ｈａｖｅ　ｂｅｅｎ　ｓｕｃｃｅｓｓｆｕｌｌｙ　ａｐｐｌｉｅｄ　ｔｏ　ｔｈｅ　ｓｙｎｔｈｅｓｉｓ　ｏｆ　ｃｈｉｒａｌ ａｌｃｏｈｏｌｓ，ａｍｉｎｅｓ　ａｎｄ　ａｍｉｎｏ　ａｃｉｄｓ　ｄｕｅ　ｔｏ　ａｄｖａｎｔａｇｅｓ　ｏｆ　ｓｈｏｒｔ　ｒｅａｃｔｉｏｎ　ｔｉｍｅ，ｌｏｗ　ｃｏｓｔ，ａｖｏｉｄａｎｃｅ　ｏｆ ａｃｃｕｍｕｌａｔｉｏｎ　ｏｆ　ｕｎｓｔａｂｌｅ　ｉｎｔｅｒｍｅｄｉａｔｅｓ　ａｎｄ　ｂｙｐｒｏｄｕｃｔｓ，ａｎｄ　ｈｉｇｈ　ｐｒｏｄｕｃｔ　ｙｉｅｌｄ．Ａｃｃｏｒｄｉｎｇ　ｔｏ ｄｉｆｆｅｒｅｎｔ　ｃａｓｃａｄｅ　ｄｅｓｉｇｎｓ，ｔｈｅ　ｕｓｅ　ｏｆ　ｏｘｉｄｏｒｅｄｕｃｔａｓｅｓ　ｉｎ　ｍｕｌｔｉ－ｅｎｚｙｍａｔｉｃ　ｃａｓｃａｄｅ　ｒｅａｃｔｉｏｎｓ　ｉｓ ｒｅｖｉｅｗｅｄ．

As highly efficient biocatalysts, enzymes have been widely used in the fields of chemical, pharmaceutical, food and energy industry with outstanding advantages. However, most enzymes face adverse conditions during the bioreaction, including high temperature, high salinity and extreme pH, and are very labile to lose activity, which severely limits their industrial applications. Therefore, it is critical and also challenging to enhance enzyme stability. Stabilizer additives supplementing is efficient to improve enzymes’ stability. The characteristics of several different types of additives and their application in enzymes’ stability enhancement were reviewed, and the underlying mechanisms were elucidated at the level of structure-function relationship.

In order to investigate the effects of marine chlorella powder on antioxidant capacity in diabetic mice, the diabetes model mice were fed with fodders containing different amount of marine chlorella powder for 28 d, and the blood glucose level in mice were monitored continuously in the whole feeding period. The levels of glucose tolerance, MDA, SOD and GSH-Px of blood serum were measured at the end of the experiment. Compared with normal control group, the weight gain levels, glucose tolerance, SOD and GSH-Px contents in all of diabetes model groups significantly decreased(p<0.05), and the blood glucose concentration and MDA increased significantly(p<0.05). Compared with model control group, the weight gain levels, glucose tolerance, SOD and GSH-Px contents increased significantly(p<0.05) in the marine chlorella powder diet intervention groups, and the blood glucose and MDA decreased significantly(p<0.05).The results showed that marine chlorella powder diet intervention had good hypoglycemic and antioxidant effects in diabetic mice, especially medium and high dose diet intervention.

Glutathione, an important active small molecule in cells and tissues, is widely used in the field of industrial production and primarily obtained by large-scale fermentation. Therefore, the efficient and specific detection of glutathione has become an important issue in its industrial production and functional studies. As a new kind of detection method, the fluorescent probe has the advantages of high sensitivity, strong specificity and low preparation cost and has been widely used in many kinds of small molecule detection. In recent years, many fluorescent probes used to detect glutathione had been reported and showed good detection performance. This paper summarized the different kinds of glutathione probes and their mechanisms were also briefly introduced.

Ａｔ　ｐｒｅｓｅｎｔ，ａｓ　ｔｈｅ　ｒｅｓｏｕｒｃｅ　ｅｘｈａｕｓｔｉｏｎ　ａｎｄ　ｅｎｖｉｒｏｎｍｅｎｔ　ｐｏｌｌｕｔｉｏｎ　ｐｒｏｂｌｅｍｓ　ｂｅｃｏｍｅ
ｍｏｒｅ　ａｎｄ　ｍｏｒｅ　ｓｅｒｉｏｕｓ，ｔｈｅ　ｐｒｏｄｕｃｔｉｏｎ　ｏｆ　ｂｉｏｐｒｏｄｕｃｔｓ　ｉｎｃｌｕｄｉｎｇ　ｂｉｏｆｕｌｅｓ　ａｎｄ　ｂｉｏｍａｔｅｒｉａｌｓ　ｆｒｏｍ
ａｇｒｉｃｕｌｔｕｒａｌ　ｗａｓｔｅ　ａｎｄ　ｏｔｈｅｒ　ｌｉｇｎｏｃｅｌｌｕｌｏｓｉｃ　ｆｅｅｄｓｔｏｃｋｓ　ｈａｓ　ａｔｔｒａｃｔｅｄ　ａ　ｇｒｅａｔ　ｄｅａｌ　ｏｆ　ａｔｔｅｎｔｉｏｎ．Ｔｈｅ
ｍｉｃｒｏｂｉａｌ　ｃｏ－ｕｔｉｌｉｚａｔｉｏｎ　ｏｆ　ｇｌｕｃｏｓｅ　ａｎｄ　ｘｙｌｏｓｅ　ｉｓ　ｅｓｓｅｎｔｉａｌ　ｉｎ　ｌｉｇｎｏｃｅｌｌｕｌｏｓｅ　ｂｉｏｒｅｆｉｎｅｒｙ，ａｎｄ
ｍｅａｎｗｈｉｌｅ　ｉｓ　ｂｅｎｅｆｉｃｉａｌ　ｉｎ　ｉｍｐｒｏｖｉｎｇ　ｆｅｒｍｅｎｔａｔｉｏｎ　ｐｅｒｆｏｒｍａｎｃｅ　ｆｏｒ　ａｒｏｍａｔｉｃ　ａｍｉｎｏ　ａｃｉｄｓ．
Ｎｅｖｅｒｔｈｅｌｅｓｓ，ｂｅｃａｕｓｅ　ｏｆ　ｔｈｅ　ｅｘｉｓｔｅｎｃｅ　ｏｆ　ｃａｒｂｏｎ　ｃａｔａｂｏｌｉｔｅ　ｒｅｐｒｅｓｓｉｏｎ （ｇｌｕｃｏｓｅ　ｅｆｆｅｃｔ），ｍｏｓｔ
ｍｉｃｒｏｂｅｓ　ｄｏｎｔ　ｈａｖｅ　ｔｈｉｓ　ａｂｉｌｉｔｙ．Ｔｈｅｒｅｆｏｒｅ，ｉｔ　ｉｓ　ｕｒｇｅｎｔ　ｔｏ　ｃｏｎｓｔｒｕｃｔ　ｓｔｒａｉｎｓ　ｔｈａｔ　ｓｉｍｕｌｔａｎｅｏｕｓｌｙ
ｕｓｅ　ｇｌｕｃｏｓｅ　ａｎｄ　ｘｙｌｏｓｅ　ｂｙ　ｍｅｔａｂｏｌｉｃ　ｅｎｇｉｎｅｅｒｉｎｇ　ｔｅｃｈｎｏｌｏｇｉｅｓ．Ｉｎ　ｔｈｉｓ　ｓｔｕｄｙ，ｔｈｅ　ｓｉｇｎｉｆｉｃａｎｃｅ　ｏｆ
ｓｉｍｕｌｔａｎｅｏｕｓ　ｕｔｉｌｉｚａｔｉｏｎ　ｏｆ　ｇｌｕｃｏｓｅ　ａｎｄ　ｘｙｌｏｓｅ　ｂｙ　ｍｉｃｒｏｂｅｓ　ｗａｓ　ｓｔａｔｅｄ，ａｓ　ｗｅｌｌ　ａｓ　ｔｈｅ　ｍｅｃｈａｎｉｓｍｓ
ｏｆ　ｇｌｕｃｏｓｅ　ｅｆｆｅｃｔ　ａｎｄ　ｉｔｓ　ｂｒｅａｋ－ｄｏｗｎ　ｍｅｔｈｏｄｓ　ｉｎ　ａｍｉｎｏ　ａｃｉｄｓ　ａｎｄ　ｎｕｃｌｅｏｔｉｄｅｓ　ｐｒｏｄｕｃｉｎｇ　ｓｔｒａｉｎｓ
ｓｕｃｈ　ａｓ　Ｅｓｈｅｒｉｃｈａｉ　ｃｏｌｉ，Ｂａｃｉｌｌｕｓ　ｓｕｂｔｉｌｉｓ，ａｎｄ　Ｃｏｒｙｎｅｂａｃｔｅｒｉｕｍ　ｇｌｕｔａｍｉｃｕｍ ｗｅｒｅ　ｅｌａｂｏｒａｔｅｄ．Ｉｎ
ａｄｄｉｔｉｏｎ，ｔｈｅ　ａｐｐｌｉｃａｔｉｏｎｓ　ｏｆ　ｇｌｕｃｏｓｅ　ａｎｄ　ｘｙｌｏｓｅ　ｃｏ－ｍｅｔａｂｏｌｉｚｉｎｇ　ｓｔｒａｉｎｓ　ｗｅｒｅ　ｉｎｔｒｏｄｕｃｅｄ．

Ａｍｉｄａｓｅｓ　ａｒｅ　ａ　ｃｌａｓｓ　ｏｆ　ｈｙｄｒｏｌａｓｅｓ，ｗｈｉｃｈ　ｃａｔａｌｙｚｅ　ｔｈｅ　ｈｙｄｒｏｌｙｓｉｓ　ｏｆ　Ｃ—Ｎ　ｂｏｎｄｓ　ｏｆｖａｒｉｏｕｓ　ａｍｉｄｅｓ　ｔｏ　ｔｈｅ　ｃｏｒｒｅｓｐｏｎｄｉｎｇ　ｃａｒｂｏｘｙｌｉｃ　ａｃｉｄｓ　ａｎｄ　ａｍｍｏｎｉａ．Ｔｈｅｙ　ａｒｅ　ｕｂｉｑｕｉｔｏｕｓ　ｉｎ　ｍａｎｙ   ｄｉｆｆｅｒｅｎｔ　ｔｙｐｅｓ　ｏｆ　ｏｒｇａｎｉｓｍｓ．Ａｃｃｏｒｄｉｎｇ　ｔｏ　ｔｈｅｉｒ　ａｍｉｎｏ　ａｃｉｄ　ｓｅｑｕｅｎｃｅｓ，ａｍｉｄａｓｅｓ　ｃａｎ　ｂｅ　ａｓｓｉｇｎｅｄ   ｉｎｔｏ　ｎｉｔｒｉｌａｓｅ　ｓｕｐｅｒｆａｍｉｌｙ　ａｎｄ　ａｍｉｄａｓｅ　ｓｉｇｎａｔｕｒｅ　ｆａｍｉｌｙ．Ｈｅｒｅ，ｗｅ　ｓｙｓｔｅｍａｔｉｃａｌｌｙ　ｒｅｖｉｅｗ　ｔｈｅ   ｐｒｏｇｒｅｓｓ　ｏｆ　ｓｔｕｄｙ　ｉｎ　ｍｏｌｅｃｕｌａｒ　ｓｔｒｕｃｔｕｒｅｓ　ａｎｄ　ｃａｔａｌｙｔｉｃ　ｍｅｃｈａｎｉｓｍｓ　ｏｆ　ａｍｉｄａｓｅｓ，ａｓ　ｗｅｌｌ　ａｓ　ｔｈｅ   ｓｐｅｃｉｆｉｃ　ｃａｔａｌｙｔｉｃ　ｐｒｏｃｅｓｓｅｓ　ｏｆ　ｓｐｅｃｉｆｉｃ　ａｍｉｄａｓｅｓ．Ａｌｌ　ｍｅｍｂｅｒｓ　ｏｆ　ｔｈｅ　ｎｉｔｒｉｌａｓｅ　ｓｕｐｅｒｆａｍｉｌｙ　ｐｏｓｓｅｓｓ   ｔｈｅ　ｃｏｎｓｅｒｖｅｄ　ｃａｔａｌｙｔｉｃ　ｔｒｉａｄ　Ｃｙｓ－Ｌｙｓ－Ｇｌｕ，ａｎｄ　ｅｘｈｉｂｉｔ　ｓｉｍｉｌａｒ　ｃａｔａｌｙｔｉｃ　ｐｒｏｃｅｓｓｅｓ．Ｔｈｅ　ｒｅｓｉｄｕｅ   Ｃｙｓ　ｉｓ　ｒｅｓｐｏｎｓｉｂｌｅ　ｆｏｒ　ｔｈｅ　ｎｕｃｌｅｏｐｈｉｌｉｃ　ａｔｔａｃｋ，Ｇｌｕ　ａｃｔｓ　ａｓ　ａ　ｇｅｎｅｒａｌ　ｂａｓｅ，ｗｈｉｌｅ　Ｌｙｓ　ｉｓ　ｉｎｖｏｌｖｅｄ　ｉｎ   ｔｈｅ　ｓｔａｂｉｌｉｚａｔｉｏｎ　ｏｆ　ｔｈｅ　ｔｒａｎｓｉｔｉｏｎ　ｓｔａｔｅｓ．Ａｓ　ｆｏｒ　ａｍｉｄａｓｅ　ｓｉｇｎａｔｕｒｅ　ｆａｍｉｌｙ，ｔｈｅ　ｃｏｎｓｅｒｖｅｄ　ｃａｔａｌｙｔｉｃ   ｔｒｉａｄ　ｉｓ　Ｓｅｒ－ｃｉｓＳｅｒ－Ｌｙｓ，ａｎｄ　ｔｈｅ　ｃａｔａｌｙｔｉｃ　ｐｒｏｃｅｓｓｅｓ　ｖａｒｙ　ｆｒｏｍ　ｄｉｆｆｅｒｅｎｔ　ｓｉｇｎａｔｕｒｅ　ａｍｉｄａｓｅｓ．   Ａｃｃｏｒｄｉｎｇ　ｔｏ　ｔｈｅ　ｒｏｌｅ　ｏｆ　Ｌｙｓ，ｔｈｅ　ｃａｔａｌｙｔｉｃ　ｍｅｃｈａｎｉｓｍ　ｃａｎ　ｂｅ　ｄｉｖｉｄｅｄ　ｉｎｔｏ　ｔｗｏ　ｔｙｐｅｓ：ｇｅｎｅｒａｌ　ａｃｉｄ
ｃａｔａｌｙｓｉｓ　ａｎｄ　ｇｅｎｅｒａｌ　ｂａｓｅ　ｃａｔａｌｙｓｉｓ．

Ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ　ｈａｓ　ｉｍｐｏｒｔａｎｔ　ｐｈｙｓｉｏｌｏｇｉｃａｌ　ｆｕｎｃｔｉｏｎｓ　ｉｎｖｏｌｖｅｄ　ｉｎ　ｓｕｇａｒ，ｆａｔ，ｐｒｏｔｅｉｎ  ａｎｄ　ｅｎｅｒｇｙ　ｍｅｔａｂｏｌｉｓｍ．Ａｓ　ｓｕｃｈ，ｉｔ　ｗａｓ　ｗｉｄｅｌｙ　ｕｓｅｄ　ａｓ　ｍｉｃｒｏｂｉａｌ　ｄｒｕｇｓ，ａｓ　ｗｅｌｌ　ａｓ　ｆｏｏｄ　ａｎｄ　ｆｅｅｄ   ａｄｄｉｔｉｖｅｓ．Ｔｏ　ｉｎｃｒｅａｓｅ　ｔｈｅ　ｙｉｅｌｄ　ｏｆ　ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ，ｔｈｅ　ｅｘｐｒｅｓｓｉｏｎ　ｏｆ　ｅｎｚｙｍｅｓ　ｒｅｓｐｏｎｓｉｂｌｅ　ｆｏｒ
ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ　ｓｙｎｔｈｅｓｉｓ　ｉｎ　Ｓａｃｃｈａｒｏｍｙｃｅｓ　ｃｅｒｅｖｉｓｉａｅ， ｓｕｃｈ　ａｓ　ｋｅｔｏｐａｎｔｏａｔｅ    ｈｙｄｒｏｘｙｍｅｔｈｙｌｔｒａｎｓｆｅｒａｓｅ， ２－ｄｅｈｙｄｒｏｐａｎｔｏａｔｅ－２－ｒｅｄｕｃｔａｓｅ， ｐａｎｔｏａｔｅ－ｂｅｔａ－ａｌａｎｉｎｅ　ｌｉｇａｓｅ　ａｎｄ   ｐｏｌｙａｍｉｎｅ　ｏｘｉｄａｓｅ　ｗｅｒｅ　ｉｎｃｒｅａｓｅｄ．Ｔｈｅ　ｙｉｅｌｄ　ｏｆ　ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ　ｒｅａｃｈｅｄ　２９０μｇ／Ｌ　ａｆｔｅｒ　１０２ｈ   ｉｎｃｕｂａｔｉｏｎ　ｉｎ　ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ－ｆｒｅｅ　ｍｅｄｉｕｍ．Ｔｈｅ　ｓｔｒａｉｎ　ＢＹＰＡＮ０１ ｗａｓ　ｆｕｒｔｈｅｒ　ｍｕｔａｔｅｄ　ｂｙ   ｍｉｃｒｏｗａｖｅ　ｉｒｒａｄｉａｔｉｏｎ　ａｎｄ　ｔｈｅ　ｏｂｔａｉｎｅｄ　ｍｕｔａｎｔ　ＢＹＰＡＮ０２ｒｅｓｕｌｔｅｄ　ｉｎ　ｐｒｏｄｕｃｔｉｏｎ　ｏｆ　４１５．７μｇ／Ｌ   ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ，ｗｈｉｃｈ　ｗａｓ　４３．３％ｈｉｇｈｅｒ　ｔｈａｎ　ｔｈａｔ　ｏｆ　ＢＹＰＡＮ０１ａｎｄ　２０３．２％ｈｉｇｈｅｒ　ｔｈａｎ　ｔｈａｔ
ｏｆ　ｗｉｌｄ　ｔｙｐｅ　ＢＹ４７４１．Ｔｈｉｓ　ｓｔｕｄｙ　ｐｒｏｖｉｄｅｓ　ａ　ｎｅｗ　ｓｔｒａｔｅｇｙ　ｆｏｒ　ｔｈｅ　ｅｎｖｉｒｏｎｍｅｎｔ－ｆｒｉｅｎｄｌｙ　ａｎｄ　ｌｏｗ   ｃｏｓｔ　ｓｙｎｔｈｅｓｉｓ　ｏｆ　ｐａｎｔｏｔｈｅｎｉｃ　ａｃｉｄ．

The effects of Ca2+ on the performance of xanthan gum were studied. Two kinds of xanthan gum with different calcium contents were prepared and the effects of Ca2+ on the viscosity of xanthan gum were analyzed. With low shear viscosity as index, the acid and heat resistance of 0.2% and 1.0% xanthan gum were tested at concentrations by adding different concentration of CaCl2. The results showed that the acid and heat resistance of high calcium xanthan gum are superior to that of low calcium xanthan gum, and sufficient Ca2+ concentration in aqueous solution would help to improve the performance of xanthan gum. The results would provide theoretical basis for improving the performance of the xanthan gum in production and application.