1.Dimethyl fumarate alleviates DEHP-induced intrahepatic cholestasis in maternal rats during pregnancy through NF-κB/NLRP3 signaling pathway
Yue Jiang ; Yun Yu ; Lun Zhang ; Qianqian Huang ; Wenkang Tao ; Mengzhen Hou ; Fang Xie ; Xutao Ling ; Jianqing Wang
Acta Universitatis Medicinalis Anhui 2025;60(1):117-123
Objective :
To investigate the protective effect of dimethyl fumarate(DMF) on maternal intrahepatic cholestasis(ICP) during pregnancy induced by di(2-ethylhexyl) phthalate(DEHP) exposure and its mechanism.
Methods :
Thirty-two 8-week-old female institute of cancer research(ICR) mice were randomly divided into 4 groups: Ctrl group, DEHP group, DMF group and DEHP+DMF group. DEHP and DEHP+DMF groups were treated with DEHP(200 mg/kg) by gavage every morning at 9:00 a.m. DMF and DEHP+DMF groups were treated with DMF(150 mg/kg) from day 13 to day 16 of gestation by gavage. After completion of gavage on day 16 of pregnancy, maternal blood, maternal liver, placenta, and amniotic fluid were collected from pregnant mice after a six-hour abrosia. The body weight of the mother rats and the body weight of the fetus rats were sorted and analyzed; the levels of total bile acid(TBA), alkaline phosphatase(ALP), aspartate aminotransferase/alanine aminotransferase(AST/ALT) in serum and TBA in liver, amniotic fluid and placenta were detected by biochemical analyzer; HE staining was used to observe the pathological changes of liver tissue; Quantitative reverse transcription PCR(RT-qPCR) was used to detect the expression levels of tumor necrosis factor-α(TNF-α), interleukin(IL)-6, IL-1, IL-18 and NOD-like receptor thermal protein domain associated protein 3(NLRP3) in the liver; Western blot was used to detect the expression of the nuclear factor KappaB(NF-κB) and NLRP3.
Results :
Compared with the control group, the body weight of the DEHP-treated dams and pups decreased(P<0.05); the levels of TBA, ALP, AST/ALT in the serum of dams and the levels of TBA in the liver, amniotic fluid, and placenta of dams increased(P<0.05); the histopathological results showed that liver tissue was damaged, bile ducts were deformed, and there was inflammatory cell infiltration around them; the levels of inflammation-related factors TNF-α, IL-6, IL-1, IL-18 and NLRP3 transcription in maternal liver increased(P<0.05); the expression of NF-κB and NLRP3 protein in maternal liver significantly increased( P<0. 05). Compared with the DEHP group,the body weight of both dams and fetuses significantly increased in DEHP + DMF group( P<0. 05); the levels of TBA,ALP,AST/ALT in the serum of dams and amniotic fluid of fetuses decreased( P<0. 05); the degree of liver lesions was improved; the transcription levels of inflammation-related factors TNF-α,IL-6,IL-1,IL-18 and NLRP3 in maternal liver decreased( P<0. 05); the expression of NF-κB and NLRP3 protein in maternal liver significantly decreased( P<0. 05).
Conclusion
DMF can effectively protect the DEHP exposure to lead to female ICP,and its mechanism may be through inhibiting the NF-κB/NLRP3 pathway and reducing liver inflammation.
2.Impact of initial screening strategies on compliance with colonoscopy for colorectal carcinoma in residents aged 50 years and above
Fang XIANG ; Zhihao HU ; Yawei WANG ; Yiying ZHANG ; Fang HUANG ; Qian PENG ; Hongjie YU ; Chaowei FU
Shanghai Journal of Preventive Medicine 2025;37(2):140-144
ObjectiveTo compare colonoscopy compliance rates under different screening strategies, to explore ways to enhance colonoscopy compliance among residents with colorectal carcinoma. MethodsResidents aged between 50‒80 years were recruited through extensive community outreach and voluntary participation. A total of 210 630 residents who participated in the colorectal carcinoma screening program in Jiading District, Shanghai, between 2013 and 2019 were selected as the research subjects. All subjects underwent a colorectal carcinoma risk assessment questionnaire survey and two fecal occult blood tests (FOBT). Positive results in the initial screening were defined as a positive questionnaire survey or a positive result in at least one FOBT. Participants with positive initial screening results were advised to undergo colonoscopy screening in a hospital. Colonoscopy results were collected from hospital reports and physician follow-ups. Compliance with colonoscopy was analyzed under different screening strategies to identify possible factors influencing residents’ willingness to undergo the procedure. ResultsA total of 21 403 individuals (10.16%) were identified as positive with the questionnaire survey, 31 595 individuals (15.00%) tested positive with at least one FOBT. Combined questionnaire and FOBT positivity was observed in 3 501 individuals (1.66%). Among the 48 453 individuals with positive initial screening results, 17 230 (35.56%) underwent colonoscopy, and a total of 315 cases of colorectal cancer were detected. The sensitivity, specificity value of FOBT initial screening were 83.81% and 84.66%, respectively. According to the combined risk assessment and FOBT initial screening preliminary screening, the lowest colonoscopy compliance rate (25.63%) was observed among individuals with only a positive questionnaire, and the highest compliance rate (52.55%) was among those with both positive questionnaire survey and two positive FOBT results. Multivariate analysis revealed that FOBT positivity had the greatest impact on colonoscopy compliance. Those with one positive FOBT test result were 2.64 times more likely to undergo colonoscopy screening than those with negative FOBT results, while individuals with two positive FOBT results were 3.18 times more likely to do so. After adjusting for FOBT results, individuals with positive questionnaire survey results were 1.43 times more likely to undergo colonoscopy screening than those with negative results (95%CI: 1.34‒1.52). Compared to questionnaire-based risk assessment, FOBT results were more influential in determining compliance with colonoscopy. ConclusionThe choice of initial screening method significantly impacts residents’ compliance with colonoscopy. While implementing colorectal carcinoma screening programs, it is necessary to strictly adhere to screening protocols, including risk assessment and FOBT. Additionally, efforts should be made to raise public awareness, encouraging residents to actively participate in risk assessments and FOBT, thereby improving their compliance with colonoscopy.
3.EGCG Promotes Aβ Clearance of Microglia Through Blockage of the HDAC6-PI3K/AKT/mTOR Signalling Axis Followed by Autophagy Activation
Yu LIN ; Kaiwen HUANG ; Honghai HONG ; Dan ZHU ; Yousheng MO ; Dongli LI ; Shuhuan FANG
Journal of Sun Yat-sen University(Medical Sciences) 2025;46(3):486-497
ObjectiveTo clarify whether epigallocatechin gallate (EGCG) is involved in the clearance of amyloid β-protein (Aβ) and autophagy induction by microglia, so as to explore the potential mechanisms of EGCG in the prevention and treatment of Alzheimer's disease (AD). MethodsSix-month-old APP/PS1 mice were randomly divided into model and EGCG groups, with some additional wild type (WT) mice as the control group, each group consisting of 15 mice. The EGCG group received continuous gavage administration[5 mg/(kg·d)] for 8 weeks, followed by the open field test and Y-maze to assess the learning and memory abilities of the mice. Thioflavin-S staining was used to evaluate the content and distribution of amyloid β-protein (Aβ)in the brain parenchyma of the mice, and immunofluorescence was employed to detect the expression levels of Aβ1-42, glial fibrillary acidic protein (GFAP), and ionized calcium-binding adapter molecule 1 (Iba1) in the hippocampal tissue of the mice. Additionally, N9 mouse microglial cells were induced with 20 µmol/L Aβ1-42, and the cell viability was measured after treatment with different concentrations of EGCG (5 µmol/L, 10 µmol/L, 20 µmol/L). Western blotting was used to detect the levels of Aβ1-42, low density lipoprotein receptor-related protein 1(LRP1), receptor for advanced glycation endproducts (RAGE), amyloid precursor protein (APP), insulin degrading enzyme (IDE), neprilysin (NEP), microtubule associated protein 1 hydrogen chain 3(LC3)-Ⅱ/LC3-Ⅰ, phosphatidylinositol 3-hydroxy kinase(PI3K), p-PI3K, protein kinase B (AKT), p-AKT, mammalian target of rapamycin (mTOR), p-mTOR, and histone deacetylase 6(HDAC6). Finally, through the co-culture of microglial cells and neuronal SH-SY5Y cells, cell viability and Caspase-3 levels were measured to verify the protective effect of EGCG-mediated Aβ clearance on neurons. ResultsEGCG increased the activity time and frequency of APP/PS1 mice in the central area of the open field (P<0.05), and enhanced the percentage of alternation in the Y-maze test (P<0.01); EGCG reduced Aβ deposition in the hippocampal tissue of APP/PS1 mice and increased the number of microglia; in vitro experiments showed that EGCG improved the survival rate of Aβ-induced N9 cells (P<0.01), upregulated RAGE activity (P<0.05), and promoted the internalization and phagocytosis of Aβ (P<0.01). ECGC activated microglial autophagy by downregulating the level of HDAC6 (P<0.05), inhibiting the phosphorylation of PI3K, AKT, mTOR (P<0.001), and increasing the LC3-Ⅱ/LC3-I ratio (P<0.001); EGCG improved the survival rate of SH-SY5Y cells (P<0.05) and reduced the activity of Caspase-3 (P<0.01) by clearing Aβ1-42 through microglia, and had a protective effect on neurons. ConclusionEGCG activates microglial autophagy to clear Aβ by targeting and inhibiting the HDAC6-PI3K/AKT/mTOR axis.
4.Lanthanide Metal Organic Framework as A New Unlabeled Fluorescence Anisotropy Probe for Detection of Phosphate Ions
Kai MAO ; Xiao-Yan WANG ; Yu-Jie LUO ; Jia-Li XIE ; Tian-Jin XIE ; Yuan-Fang LI ; Cheng-Zhi HUANG ; Shu-Jun ZHEN
Chinese Journal of Analytical Chemistry 2024;52(1):35-44,中插1-中插4
Fluorescence anisotropy(FA)analysis has many advantages such as no requirement of separation,high throughput and real-time detection,and thus has been widely used in many fields,including biochemical analysis,food safety detection,environmental monitoring,etc.However,due to the small volume or mass of the target,its combination with the fluorescence probe cannot produce significant signal change.To solve this issue,researchers often use nanomaterials to enhance the mass or volume of fluorophore to improve the sensitivity.Nevertheless,this FA amplification strategy also has some disadvantages.Firstly,nanomaterials are easy to quench fluorescence.As a result,the FA value is easily influenced by light scattering,which reduces the detection accuracy.Secondly,fluorescent probes in most methods require complex modification steps.Therefore,it is necessary to develop new FA probes that do not require the amplification of volume and mass or modification.As a new kind of nanomaterials,luminescent metal-organic framework(MOF)has a large volume(or mass)and strong fluorescence emission.It does not require additional signal amplification materials.As a consequence,it can be used as a potential FA probe.This study successfully synthesized a lanthanide metal organic framework(Ce-TCPP MOF)using cerium ion(Ce3+)as the central ion and 5,10,15,20-tetra(4-carboxylphenyl)porphyrin(H2TCPP)as the ligand through microwave assisted method,and used it as a novel unmodified FA probe to detect phosphate ions(Pi).In the absence of Pi,Ce-TCPP MOF had a significant FA value(r).After addition of Pi,Pi reacted with Ce3+in MOF and destroyed the structure of MOF into the small pieces,resulting in a decrease in r.The experimental results indicated that with the increase of Pi concentration,the change of the r of Ce-TCPP MOF(Δr)gradually increased.The Δr and Pi concentration showed a good linear relationship within the range of 0.5-3.5 μmol/L(0.016-0.108 mg/L).The limit of detection(LOD,3σ/k)was 0.41 μmol/L.The concentration of Pi in the Jialing River water detected by this method was about 0.078 mg/L,and the Pi value detected by ammonium molybdate spectrophotometry was about 0.080 mg/L.The two detection results were consistent with each other,and the detection results also meet the ClassⅡwater quality standard,proving that this method could be used for the detection of Pi in complex water bodies.
5.Budget impact analysis for adjusting the price of carotid endarterectomy over the next five years
Zhe-Yi FANG ; Jin-Yu LIU ; Jia-Yan HUANG
Fudan University Journal of Medical Sciences 2024;51(2):230-237
Objective To analyze the budget impact of a price increase for carotid endarterectomy(CEA)on the total expenditure of health insurance expenditure in China.Methods We set 2021 as the base year,and 2022-2026 as the study years.A budget impact analysis model was developed to calculate the expenditure of health insurance funds over the next 5 years following a 30%price increase for carotid endarterectomy.Data on the target population,treatment costs,and market share changes both nationwide and in four sample cities were used.The data was collected in May to Jul 2022.Results The price increase for carotid endarterectomy will reduce total health insurance fund expenditures nationwide by 143.176 2 million yuan over five years.Total health insurance fund expenditures in the sample cities will also decrease to varying degrees.The higher the price increase for the surgical procedure,the greater the decrease in total expenditure of the health insurance fund.The market share of the surgical procedure has the greatest impact on the total expenditure of the health insurance fund.Conclusion Increasing the price of carotid endarterectomy may lead to increase in its market share and decline in the health insurance fund expenditures in future five years.
6.Establishment and application of a prospective follow-up research method for acute infectious diseases in Shanghai community residents
Yaxu ZHENG ; Xiao YU ; Huanyu WU ; Liming WU ; Jian CHEN ; Wenjia XIAO ; Zhuoying HUANG ; Sheng LIN ; Qiwen FANG ; Rui LIU ; Hao ZHANG ; Xin CHEN
Shanghai Journal of Preventive Medicine 2024;36(1):5-10
ObjectiveTo present the exploration and application of a prospective follow-up research method for acute infectious disease surveillance based on natural community populations, using COVID-19 infection as an example, and to provide a reference for improving the infectious disease surveillance and early warning system. MethodsA multi-stage probability proportional sampling method was employed to sample residents from all communities of 16 administrative districts in Shanghai, with households as the units. A cohort for acute infectious diseases based on natural community populations was established. The baseline survey was conducted for all cohort subjects, and COVID-19 antigen test kits were distributed. From December 21, 2022 to September 30, 2023, prospective follow-up monitoring of COVID-19 antigen and nucleic acid was carried out on the study subjects on a weekly basis. The baseline characteristics and follow-up information of the cohort subjects were described. ResultsThe cohort for acute infectious diseases included a total of 12 881 subjects, comprising 6 098 males (47.3%) and 6 783 females (52.7%). The baseline survey revealed that 35.2% (4 540/12 881) of the subjects had a history of COVID-19 infection. During the follow-up period from December 21, 2022 to September 30, 2023, the average incidence density in the cohort was 0.61/person-year, with a higher incidence density in females (0.63/person-year) compared to males (0.59/person-year). Individuals aged 60 and above (0.64/person-year) and those with underlying health conditions (0.67/person-year) had a higher incidence density. Healthcare workers showed a notably higher incidence density (0.84/person-year) than that in other occupational groups. As of September 30, 2023, a total of 340 subjects in the cohort experienced secondary infections, with a median interval of 170 days between the first and second infections. ConclusionThis study applies cohort study method to acute infectious disease surveillance, providing crucial data support for estimating infection rates and forecasting alerts for acute infectious diseases in the community. This method can be promoted and applied as a new approach for acute infectious disease surveillance.
7.Research on the Improvement Path of Medical Staff's Report Intention on Adverse Events Based on Technology Acceptance Model
Jin WU ; Xinlu TONG ; Binru FANG ; Yu QIAN ; Yuwei FAN ; Xianhong HUANG ; Yongting YANG ; Liming ZHU
Chinese Hospital Management 2024;44(11):51-54,78
Objective Based on the technology acceptance model,to explore the influence mechanism of technical support,perceived interactivity,perceived usefulness,perceived ease of use and perceived risk on medical staff's report intention on adverse events,and to provide path suggestions for improving medical staff's report intention adverse events.Methods The multi-stage sampling method was used to select 637 medical staffs of tertiary public hospitals in Hangzhou who used the information-based platform to report adverse events as the research respondents,and the self-developed scale of report intention on adverse events was used as the research tool,monofactor analysis were conducted by Wilcoxon rank-sum test,and the structural equation model was used to analyze the influence path of their report intention on adverse events.Results Perceived ease of use and perceived usefulness have positive effects on medical staff's report intention on adverse events(β=0.264,0.658;P<0.001);Perceived risk negatively affected the medical staff's report intention on adverse events(β=-0.143,P<0.001).The indirect effects of perceived usefulness and perceived ease of use on medical staff's report intention on adverse events are 0.538 and 0.205,respectively.Conclusion Perceived usefulness and perceived ease of use plays a mediating role in perceived interactivity and medical staff's report intention on adverse events.
8.Expert consensus on surgical treatment of oropharyngeal cancer
China Anti-Cancer Association Head and Neck Oncology Committee ; China Anti-Cancer Association Holistic Integrative Oral Cancer on Preventing and Screen-ing Committee ; Min RUAN ; Nannan HAN ; Changming AN ; Chao CHEN ; Chuanjun CHEN ; Minjun DONG ; Wei HAN ; Jinsong HOU ; Jun HOU ; Zhiquan HUANG ; Chao LI ; Siyi LI ; Bing LIU ; Fayu LIU ; Xiaozhi LV ; Zheng-Hua LV ; Guoxin REN ; Xiaofeng SHAN ; Zhengjun SHANG ; Shuyang SUN ; Tong JI ; Chuanzheng SUN ; Guowen SUN ; Hao TIAN ; Yuanyin WANG ; Yueping WANG ; Shuxin WEN ; Wei WU ; Jinhai YE ; Di YU ; Chunye ZHANG ; Kai ZHANG ; Ming ZHANG ; Sheng ZHANG ; Jiawei ZHENG ; Xuan ZHOU ; Yu ZHOU ; Guopei ZHU ; Ling ZHU ; Susheng MIAO ; Yue HE ; Jugao FANG ; Chenping ZHANG ; Zhiyuan ZHANG
Journal of Prevention and Treatment for Stomatological Diseases 2024;32(11):821-833
With the increasing proportion of human papilloma virus(HPV)infection in the pathogenic factors of oro-pharyngeal cancer,a series of changes have occurred in the surgical treatment.While the treatment mode has been im-proved,there are still many problems,including the inconsistency between diagnosis and treatment modes,the lack of popularization of reconstruction technology,the imperfect post-treatment rehabilitation system,and the lack of effective preventive measures.Especially in terms of treatment mode for early oropharyngeal cancer,there is no unified conclu-sion whether it is surgery alone or radiotherapy alone,and whether robotic minimally invasive surgery has better func-tional protection than radiotherapy.For advanced oropharyngeal cancer,there is greater controversy over the treatment mode.It is still unclear whether to adopt a non-surgical treatment mode of synchronous chemoradiotherapy or induction chemotherapy combined with synchronous chemoradiotherapy,or a treatment mode of surgery combined with postopera-tive chemoradiotherapy.In order to standardize the surgical treatment of oropharyngeal cancer in China and clarify the indications for surgical treatment of oropharyngeal cancer,this expert consensus,based on the characteristics and treat-ment status of oropharyngeal cancer in China and combined with the international latest theories and practices,forms consensus opinions in multiple aspects of preoperative evaluation,surgical indication determination,primary tumor re-section,neck lymph node dissection,postoperative defect repair,postoperative complication management prognosis and follow-up of oropharyngeal cancer patients.The key points include:① Before the treatment of oropharyngeal cancer,the expression of P16 protein should be detected to clarify HPV status;② Perform enhanced magnetic resonance imaging of the maxillofacial region before surgery to evaluate the invasion of oropharyngeal cancer and guide precise surgical resec-tion of oropharyngeal cancer.Evaluating mouth opening and airway status is crucial for surgical approach decisions and postoperative risk prediction;③ For oropharyngeal cancer patients who have to undergo major surgery and cannot eat for one to two months,it is recommended to undergo percutaneous endoscopic gastrostomy before surgery to effectively improve their nutritional intake during treatment;④ Early-stage oropharyngeal cancer patients may opt for either sur-gery alone or radiation therapy alone.For intermediate and advanced stages,HPV-related oropharyngeal cancer general-ly prioritizes radiation therapy,with concurrent chemotherapy considered based on tumor staging.Surgical treatment is recommended as the first choice for HPV unrelated oropharyngeal squamous cell carcinoma(including primary and re-current)and recurrent HPV related oropharyngeal squamous cell carcinoma after radiotherapy and chemotherapy;⑤ For primary exogenous T1-2 oropharyngeal cancer,direct surgery through the oral approach or da Vinci robotic sur-gery is preferred.For T3-4 patients with advanced oropharyngeal cancer,it is recommended to use temporary mandibu-lectomy approach and lateral pharyngotomy approach for surgery as appropriate;⑥ For cT1-2N0 oropharyngeal cancer patients with tumor invasion depth>3 mm and cT3-4N0 HPV unrelated oropharyngeal cancer patients,selective neck dissection of levels ⅠB to Ⅳ is recommended.For cN+HPV unrelated oropharyngeal cancer patients,therapeutic neck dissection in regions Ⅰ-Ⅴ is advised;⑦ If PET-CT scan at 12 or more weeks after completion of radiation shows intense FDG uptake in any node,or imaging suggests continuous enlargement of lymph nodes,the patient should undergo neck dissection;⑧ For patients with suspected extracapsular invasion preoperatively,lymph node dissection should include removal of surrounding muscle and adipose connective tissue;⑨ The reconstruction of oropharyngeal cancer defects should follow the principle of reconstruction steps,with priority given to adjacent flaps,followed by distal pedicled flaps,and finally free flaps.The anterolateral thigh flap with abundant tissue can be used as the preferred flap for large-scale postoperative defects.
9.Efficacy of 6% hydroxyethyl starch 130/0.4 electrolyte solution for fluid therapy in patients undergoing meningioma resection
Yaling CHANG ; Yu ZHANG ; Xiang HUANG ; Juan LI ; Fang KANG
Chinese Journal of Anesthesiology 2024;44(1):80-84
Objective:To evaluate the efficacy of 6% hydroxyethyl starch (HES) 130/0.4 electrolyte solution for fluid therapy in the patients undergoing meningioma resection.Methods:Ninety-two American Society of Anesthesiologists Physical Status classification Ⅰ or Ⅱ patients of either sex, aged 18-64 yr, with body mass index of 18-30 kg/m 2, with expected operation duration>3 h, undergoing elective meningioma resection, were divided into 2 groups ( n=46 each) using a random number table method: lactated Ringer′s solution (LR) group and HES group. LR was infused throughout operation in group LR, and 6% HES was intravenously infused in group HES, with the maximum dose not exceeding 50 ml/kg, and the excess part was supplemented with LR. Goal-directed fluid therapy was used to maintain stroke volume variation<13% and mean arterial pressure 70-90 mmHg. Arterial blood gas analysis was performed immediately before anesthesia induction (T 0), when 1 000 and 2 000 ml of fluid were infused (T 1, 2), and at the end of surgery (T 3) to record electrolyte and acid-base balance indexes. Thromboelastogram was simultaneously monitored. The occurrence of electrolyte disorder, acid-base imbalance and abnormal coagulation function and consumption of norepinephrine were recorded. Patients were followed up at 3 and 7 days after surgery, and the Chinese quality of recovery-15 scores were recorded. The hospitalization time and occurrence of brain edema, pulmonary edema, nausea and vomiting were recorded. Results:In group L and group H, 4 cases and 6 cases were excluded due to prolonged operation time, and 42 cases and 40 cases were finally included, respectively. Compared with LR group, the plasma Na + concentration was significantly increased at T 3, the plasma Cl - concentration and pH value were increased at T 1-3, the plasma Ca 2+ concentration was decreased at T 2, 3, reaction time was increased at T 3, coagulation time was increased and maximum amplitude was decreasedat T 2, 3, and coagulation Angle was decreased at T 1-3( P<0.05). No electrolyte disorder and abnormal coagulation function was found in the two groups. There was no statistically significant difference in the consumption of norepinephrine, postoperative Chinese quality of recovery-15 score, length of hospital stay and incidence of alkalosis, pulmonary edema, brain edema, and nausea and vomiting between the two groups ( P>0.05). Conclusions:The efficacy of liquid therapy is comparable between HES and LR in the patients undergoing meningioma resection.
10.Extraction process,enzymatic properties and practical application of glucuronic hydrolase in Scutellaria baicalensis stems and leaves
Yu-Jie CHENG ; Xu CHEN ; Yun-Hua LIU ; Zhi-Fang HUANG ; Yan CHEN ; Yu-Hong LIU ; Jin-Hai YI
Chinese Traditional Patent Medicine 2024;46(1):35-40
AIM To study the extraction process,enzymatic properties and practical application of glucuronic hydrolase in Scutellaria baicalensis stems and leaves(sbsl GUS).METHODS With granularity,water consumption,extraction time and extraction frequency as influencing factors,enzymatic activity as an evaluation index,the extraction process was optimized by orthogonal test on the basis of single factor test.The relationship between substrate(baicalin)concentration and enzymolysis rate,after which Vmax and Km were calculated,the effects of pH value,temperature and metal ion on enzymatic activity were investigated,pH stability and heat stability were evaluated.sbsl GUS was adotped in the enzymolysis of baicalin to prepare baicalein,then the effects of pH value,temperature,reaction time,initial substrate concentration and enzyme addition on transfer rate were investigated.RESULTS The optimal extraction process was determined to be 40 mesh for granularity,10 times for water consumption,15 min for extraction time,and 3 times for extraction frequency.The enzymolysis accorded with the kinetics of enzymatic reaction,Km was 0.006 3 mol/L,Vmax was 70.42 μmol/h,the strongest enzymatic activity was found at the pH value of 6.0,temperature of 45℃and metal ion of 100 mmol/L Cu2+,sbsl GUS demonstrated good stability at the ranges of 4.0-7.0 for pH value and 4-30℃for temperature.The optimal preparation process was determined to be 6.0 for pH value,45℃for temperature,more than 12 h for reaction time,67.2 mmol/L for initial substrate concentration,and 1 mL/0.269 mmol baicalin for enzyme addition,the transfer rate was 97.83%.CONCLUSION sbsl GUS enzymolysis exhibits high efficiency and mild condition,which can provide a simple preparation method for obtaining baicalein,and expand the application path of Scutellaria baicalensis stems and leaves.


Result Analysis
Print
Save
E-mail