Causal associations between gastroesophageal reflux disease and essential hypertension: A bidirectional Mendelian randomization study

BACKGROUND Clinical studies have reported that patients with gastroesophageal reflux disease(GERD)have a higher prevalence of hypertension.AIM To performed a bidirectional Mendelian randomization(MR)analysis to investi-gate the causal link between GERD and essential hypertension.METHODS Eligible single nucleotide polymorphisms(SNPs)were selected,and weighted median,inverse variance weighted(IVW)as well as MR egger(MR-Egger)re-gression were used to examine the potential causal association between GERD and hypertension.The MR-Pleiotropy RESidual Sum and Outlier analysis was used to detect and attempt to reduce horizontal pleiotropy by removing outliers SNPs.The MR-Egger intercept test,Cochran’s Q test and“leave-one-out”sen-sitivity analysis were performed to evaluate the horizontal pleiotropy,heterogen-eities,and stability of single instrumental variable.RESULTS IVW analysis exhibited an increased risk of hypertension(OR=1.46,95%CI:1.33-1.59,P=2.14E-16)in GERD patients.And the same result was obtained in replication practice(OR=1.002,95%CI:1.0008-1.003,P=0.000498).Meanwhile,the IVW analysis showed an increased risk of systolic blood pressure(β=0.78,95%CI:0.11-1.44,P=0.021)and hypertensive heart disease(OR=1.68,95%CI:1.36-2.08,P=0.0000016)in GERD patients.Moreover,we found an decreased risk of Barrett's esophagus(OR=0.91,95%CI:0.83-0.99,P=0.043)in essential hypertension patients.CONCLUSION We found that GERD would increase the risk of essential hypertension,which provided a novel prevent and therapeutic perspectives of essential hypertension.

Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension

Background:Gastroesophageal variceal bleeding is one of the most severe complications of patients with cirrhosis.Although primary prevention drugs,including non-selectiveβ-blockers,have effectively reduced the incidence of bleeding,their efficacy is limited due to side effects and related contraindications.With recent advances in precision medicine,precise drug treatment provides better treatment efficacy.Data sources:Literature search was conducted in PubMed,MEDLINE and Web of Science for relevant articles published up to May 2022.Information on clinical trials was obtained from https://clinicaltrials.gov/and http://www.chictr.org.cn/.Results:The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising drugs.According to the site of action,these drugs could be classified into four classes:intrahepatic,extrahepatic,both intrahepatic and extrahepatic targets and others.All these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.Conclusions:This review classified and summarized the promising drugs,which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension,demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.

Adherence to Pharmacotherapy in Post-Menopausal Women with Hypertension or Metabolic Syndrome: Real World Experience

Background: Adherence to medications is dependent upon a variety of factors, including individual characteristics of the patient, interactions with health care providers, and medication complexity. Even though several studies were conducted to test intervention strategies, results are uncertain. Aim: The aim of the study is to assess if a tailored combined intervention strategy improves medication adherence in a large population of post-menopausal women affected by hypertension or metabolic syndrome. Methods: We enrolled 6833 patients aged 50 to 69 years, 85.7% with hypertension, and 14.3% with metabolic syndrome. A network between patients, general practitioners, and cardiologists was established. Interventions included education, adequate information to patients, a simplified scheme of treatment, and periodic adherence assessment. These were either delivered as healthcare provider supports or using modern technology. Medication adherence was estimated by the proportion of days covered for all classes of drugs after the index date. Results: Non-adherent hypertensive women were 297 (5%), and those with metabolic syndrome were 73 (7.4%) (p Conclusions: The rate of non-adherence in both settings of postmenopausal women was 7.7%, much lower than that described in the literature. This rate was increased in patients with metabolic syndrome;probably it is related to the complexity of the therapeutic scheme or to a poor consciousness of the disease. Therefore, implementing a tailored combined intervention can improve significantly patients’ adherence to medical therapy.

Analyzing the potential mechanism of Buyang Huanwu decoction for the treatment of salt-sensitive hypertension based on network pharmacology and in vivo experiments

Background:Buyang Huanwu decoction(BHD)is a traditional Chinese medicine herbal formula used for treating hypertension,particularly in the later stages of hypertension when it is associated with intracerebral hemorrhage.This study aims to investigate the treatment mechanism of BHD to provide a basis for its clinical application in hypertension treatment.Methods:Network pharmacology analysis and cell culture experiments were performed to explore the potential proteins and mechanisms of action of BHD against hypertension.Bioactive compounds related to BHD were screened,and relevant targets associated with hypertension and BHD were retrieved.Molecular docking technology was used to identify the effective signaling pathway based on the Kyoto Encyclopedia of Genes and Genomes and protein-protein interaction network cores.Lastly,the effects and mechanisms of BHD on salt-sensitive hypertensive endothelial cells were investigated.Results:Ninety-three potential therapeutic targets for BHD and salt-sensitive hypertension were found to be closely associated with the PI3K/Akt/eNOS signaling pathway and oxidative stress.Cell experiments further indicated the pivotal role of endothelial cells in hypertension,and validation analysis showed that BHD significantly preserved cell morphology,suppressed oxidative stress reactions,activated the PI3K/Akt/eNOS signaling pathways,preserved normal endothelial cell function,and reduced cell apoptosis.Conclusion:BHD effectively activates the PI3K/Akt/VEGF signaling pathway,attenuates oxidative stress-induced injury in endothelial cells exposed to high salt levels,and mitigates apoptosis,supporting the use of traditional Chinese medicine BHD in the treatment of salt-sensitive hypertension.

Investigating causal links between gastroesophageal reflux disease and essential hypertension

Gastroesophageal reflux disease(GERD)is a prevalent global health concern with a rising incidence.Various risk factors,including obesity,hiatal hernia,and smo-king,contribute to its development.Recent research suggests associations bet-ween GERD and metabolic syndrome,cardiac diseases,and hypertension(HTN).Mechanisms linking GERD to HTN involve autonomic dysfunction,inflammatory states,and endothelial dysfunction.Furthermore,GERD medications such as pro-ton-pump inhibitors may impact blood pressure regulation.Conversely,antihy-pertensive medications like beta-blockers and calcium channel blockers can exacerbate GERD symptoms.While bidirectional causality exists between GERD and HTN,longitudinal studies are warranted to elucidate the precise relationship.Treatment of GERD,including anti-reflux surgery,may positively influence HTN control.However,the interplay of lifestyle factors,comorbidities,and medications necessitates further investigation to comprehensively understand this relation-ship.In this editorial,we comment on the article published by Wei et al in the recent issue of the World Journal of Clinical Cases.We evaluate their claims on the causal association between GERD and HTN.

Spleen volume is associated with overt hepatic encephalopathy after transjugular intrahepatic portosystemic shunt in patients with portal hypertension

BACKGROUND Portal shunt and immune status related to the spleen are related to the occurrence of hepatic encephalopathy(HE).It is unknown whether spleen volume before transjugular intrahepatic portosystemic shunt(TIPS)is related to postoperative HE.AIM To investigate the relationship between spleen volume and the occurrence of HE.METHODS This study included 135 patients with liver cirrhosis who underwent TIPS,and liver and spleen volumes were elevated upon computed tomography imaging.The Kaplan-Meier curve was used to compare the difference in the incidence rate of HE among patients with different spleen volumes.Univariate and multivariate Cox regression analyses were performed to identify the factors affecting overt HE(OHE).Restricted cubic spline was used to examine the shapes of the dose-response association between spleen volumes and OHE risk.RESULTS The results showed that 37(27.2%)of 135 patients experienced OHE during a 1-year follow-up period.Compared with preoperative spleen volume(901.30±471.90 cm3),there was a significant decrease in spleen volume after TIPS(697.60±281.0 cm^(3))in OHE patients.As the severity of OHE increased,the spleen volume significantly decreased(P<0.05).Compared with patients with a spleen volume≥782.4 cm^(3),those with a spleen volume<782.4 cm^(3) had a higher incidence of HE(P<0.05).Cox regression analysis showed that spleen volume was an independent risk factor for post-TIPS OHE(hazard ratio=0.494,P<0.05).Restricted cubic spline model showed that with an increasing spleen volume,OHE risk showed an initial increase and then decrease(P<0.05).CONCLUSION Spleen volume is related to the occurrence of OHE after TIPS.Preoperative spleen volume is an independent risk factor for post-TIPS OHE.

AGTR1 A1166C gene polymorphism is associated with the effectiveness of valsartan monotherapy in Chinese patients with essential hypertension:A retrospective analysis

Objective:To investigate whether angiotensinⅡtype 1 receptor(AGTR1 A1166C)gene polymorphism was associated with the effectiveness of valsartan monotherapy in Chinese patients with essential hypertension.Methods:This retrospective analysis included 198 patients(≥18 years of age)who received valsartan monotherapy(80 mg/day)for newly developed essential hypertension at the authors’center between January 1,2020 and December 31,2023.Genotyping for AGTR1 A1166C gene polymorphism was done by polymerase chain reaction(PCR)-melting curve analysis of genomic DNA from peripheral blood samples.A dominant genetic model for AGTR1 A1166C(AA genotype versus AC+CC genotype)was used.Multivariate regression analysis of baseline variables and AGTR1 polymorphism was conducted to identify predictors of target blood pressure attainment(<140/90 mmHg)at the 4-week follow-up.Results:The median age of the 198 patients was(53.7±13.5)years,and 58%were men.Genotyping assays showed that 164 patients had the AA genotype,and 34 patients were of the AC/CC genotype,including 30 with the AC genotype and 4 with the CC genotype.Allele distribution was consistent with Hardy Weinberg equilibrium.109 Patients(55.1%)attained the blood pressure target.Multivariate analysis showed that smoking(versus no smoking,HR 0.314,95%CI 0.159-0.619,P=0.001)and AGTR1 A1166C AA genotype(versus AC/CC,HR 2.927,95%CI 1.296-6.611,P=0.023)were significant and independent predictors of target attainment.25 Patients(73.5%)with AGTR1 A1166C AC/CC genotype attained the target versus 51.2%(51/164)of patients with AGTR1 A1166C AA genotype(P=0.017).Patients with AGTR1 A1166C AC/CC genotype had a significantly greater reduction in systolic blood pressure[(33.1±10.8)mmHg versus(29.2±11.7)mmHg in AA carriers;(P=0.029)].Conclusions:Hypertensive patients carrying one or two C alleles of the AGTR1 A1166C gene were more responsive to valsartan treatment.

The Association Between Daily Physical Activity and Risk of Hypertension in Middle-Aged and Older Adults:A Nationwide Cohort Study in China

Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA and hypertension are not consistent, and little is known about this relationship within the Chinese middle-aged and older people. We investigated the relationship between PA and hypertension within this population using China Health and Nutrition Survey 1991-2015 data. Physical activity was expressed in terms of the metabolic equivalent task (MET) and participants were divided into groups according to quartiles, namely, Q1 (< 32.97 METs-h/w), Q2 (32.97-60.38 METs-h/ w), Q3 (60.38-98.95 METs-h/w), and Q4 (> 98.95 METs-h/w). Compared with the Q1 group, the odds ratio of risk with hypertension (95% CIs) after adjusting for confounding factors were 0.63 (0.35, 1.12), 0.49 (0.28, 0.86), and 0.62 (0.35, 1.09) for those in Q2, Q3, and Q4, respectively. Restricted cubic spline functions were used and a U-shaped relationship between physical activity and hypertension risk was found, indicative of an optimal level of physical activity, which was found to be 112 METs-h/w. Our data suggest maintenance of optimal levels of total daily physical activity may be important for preventing hypertension in Chinese adults over the age of 40.

Evaluation of the Effectiveness of Community Pharmacy Services on Rational Medication Use in Elderly Patients with Hypertension and Diabetes

Objective:To explore the effect of community pharmacy services on rational medication use in elderly patients with hypertension and diabetes.Methods:Between November 2022 and December 2023,80 elderly patients with hypertension and diabetes were selected and randomly divided into a control group(routine medication guidance)and an observation group(community pharmacy services),with 40 subjects each.The medication effect scores,blood pressure,blood sugar levels,and quality of life scores before and after intervention were compared between the two groups.Results:Comparison of pharmaceutical knowledge,medication compliance,and safe medication behavior scores showed that the observation group had higher scores as compared to the control group(P<0.05);blood pressure(systolic blood pressure,diastolic blood pressure,heart rate)and blood sugar(fasting blood glucose,2 h postprandial blood glucose,glycated hemoglobin)index levels were compared,and the observation group’s index levels were lower than those of the control group(P<0.05);the scores of physical health,mental health,social relationships,and environment in the observation group were higher than those in the control group(P<0.05).Conclusion:Community pharmacy services improved the rational medication effect of elderly patients with hypertension and diabetes,and improved their blood pressure,blood sugar control levels,and quality of life.

pH值调控方法对剩余污泥与柑橘废渣厌氧共发酵产酸影响

考察不同pH值调控方法对剩余污泥和柑橘废渣共发酵系统的产酸性能影响,结果表明:持续调节pH值为6可以提高共发酵系统的增溶过程,促进糖类物质水解,增强产酸和产甲烷过程,VFA产量和累积甲烷产量分别是空白组的1.36倍和1.25倍;提高共发酵系统中水解细菌和发酵产酸细菌的菌群丰度,促使甲烷生成途径从乙酰分解途径转向氢化营养途径.调节初始pH值为10可以有效促进共发酵系统中溶解性有机物的释放和达到快速水解的目的,促进产酸性能,但对产甲烷过程有抑制作用.

Association of Glu298Asp Polymorphism of the En-dothelial Nitric Oxide Synthase Gene with Essential Hypertension in Elderly People

Objective: To investigate the association of Glu298Asp polymorphism of theeNOS gene with essential hypertension in elderly people. Methods: Ninety-five cases of essentialhypertension were randomly chosen from outpatients and inpatients as the study group, and an equalnumber of sexes, age-matched healthy people as the control group. Their height, weight and bloodpressure were recorded and their fasting plasma lipid concentrations were measured. Glu298Asppolymorphism of the eNOS gene was measured using the methods of PCR and RFLP. Results: Theconstituent ratio of Genotype Glu/Asp in the study group (26.3%) was higher than that in the controlgroup (12.6%, x^2 = 5. 67, P<0.05), the allelic frequency of 298Asp in the study group (13.2%) wassignificantly higher than that in the control group (6.3%, x^2 = 5.06, P<0.05). Conclusion: Glu298Asp variant of the eNOS gene may be an independent predictor in essential hypertension.

改进和优化黑果枸杞及其制品中花青素测定的pH示差法

建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质谱法鉴别出黑果枸杞中花青素的具体化学结构,并计算出混合花青素的平均摩尔质量。通过分光光度法测得混合花青素的平均摩尔消光系数,对改进后的pH示差法进行方法学验证和花青素的含量测定。结果显示,最佳提取和检测条件如下:黑果枸杞花青素提取溶剂为盐酸-80%(体积分数)乙醇(3∶97,体积比),料液比为1∶100(g∶mL),提取温度为50℃,提取时间为30 min,缓冲溶液稀释5倍后静置平衡20 min。液相色谱-三重四级杆串联质谱法鉴别黑果枸杞中主要以矮牵牛素类花青素为主(占97.96%),黑果枸杞特有的混合花青素平均摩尔质量为912.7 g/mol,平均摩尔消光系数为29591 L/(mol·cm)。pH示差法改进后能够满足方法学验证要求,固体样品和液体样品最低检出限分别为28.2 mg/100 g、0.282 mg/100 mL。方法改进后花青素提取增长率均大于20%,静置平衡20 min后单次检测结果精密度小于0.3%。以矮牵牛素类花青素代替矢车菊素-3-O-葡萄糖苷计算花青素含量平均提高了2.41倍,能真实地反映黑果枸杞及其制品中花青素的含量。

两种调理剂对水稻土pH值和重金属吸收的影响

探明两种调理剂对近中性水稻土pH值、重金属有效性和水稻吸收的影响,及其与土壤性质的关系,为调理剂的科学开发及合理施用提供科学依据。选取水淬高炉渣源调理剂(T1)及其腐殖质改性调理剂(T2),分别设置2个施用量梯度(T1L、T1H和T2L、T2H),通过盆栽试验分析了两种调理剂及不同用量对土壤pH值、有效硅、镉、锌、铜含量,以及水稻籽粒和秸秆镉、锌、铜含量的影响。与对照(CK)相比,2个施用T1调理剂处理土壤pH值分别升高0.64和1.02,2个施用T2调理剂处理pH值分别升高0.27和0.56(P<0.05),土壤pH值随调理剂施用量的增加而增加。T1L和T1H处理土壤有效硅含量与CK相比分别提高5和22倍(P<0.05),且显著高于施用T2调理剂处理。与CK相比,T1H处理土壤有效镉、锌、铜含量分别降低37.21%、45.57%和95.30%(P<0.05);T2L和T2H处理土壤有效锌含量分别降低31.55%和30.67%,有效铜含量分别降低6.53%和19.32%(P<0.05)。与CK相比,T1L和T1H水稻籽粒锌含量分别降低23.44%和18.12%(P<0.05);施用T2调理剂后,籽粒和秸秆锌、铜含量无显著变化。土壤pH值、有效硅含量与土壤有效镉、锌、铜含量呈显著或极显著负相关,土壤有效硅含量与籽粒、秸秆镉含量呈显著负相关。研究表明,在近中性水稻土上施用富含硅的强碱性调理剂,既有利于提高土壤p H值和有效硅含量,又可有效降低土壤重金属有效性及其水稻吸收量。

面向栽培基质的二氧化钛电极EGFET pH传感器设计

针对农业生产中栽培基质直接在线检测pH准确性差的问题,采用化学腐蚀法,制备出具有氢离子敏感特性和超亲水特性的二氧化钛(TiO_(2))电极,并且采用退火工艺以提高电极表面硬度;将TiO_(2)电极与金属氧化物场效应晶体管(MOSFET)组合成基于延伸式栅极场效应晶体管(EGFET)的pH传感器.测试得到传感器灵敏度为0.05063 V/pH,重复性试验的变异系数最大为0.0057.测试结果表明该传感器具有良好的灵敏度、重复性和稳定性.选取4种典型栽培基质进行pH在线检测应用试验,pH检测误差的绝对值最大为0.18,经过温度补偿后误差的绝对值最大为0.11;使用后电极表面的亲水性依旧保持良好.应用试验结果表明,该传感器适用于栽培基质pH在线检测.

暗褐脉柄牛肝菌产淀粉水解酶最适温度及最适初始pH研究

以20113和21014暗褐脉柄牛肝菌菌株为试材,采用刚果红、卢戈氏碘液变色圈法,研究了温度、pH对暗褐脉柄牛肝菌产淀粉水解酶能力的影响,以期为研发暗褐脉柄牛肝菌淀粉高效利用方案提供参考依据。结果表明:刚果红变色圈试验中,随着温度升高,菌丝生长速率、淀粉水解酶指数逐渐升高,并在28℃达到最大值,随后逐渐下降;卢戈氏碘液变色圈试验中,随着温度升高,菌丝生长速率、淀粉水解酶指数逐渐升高,并分别在30℃和28℃达到最大值,随后逐渐降低;随着初始pH逐渐升高,淀粉水解酶指数逐渐升高并在pH 6.5时达到最大值,pH 7.0~8.0变化不显著;随着pH升高,21014菌株生长速率逐渐降低,20113菌株生长速率无显著变化。综上,暗褐脉柄牛肝菌产淀粉水解酶最适宜温度为30℃,最适初始pH为6.5。

激素及pH对大蒜愈伤组织诱导研究

探讨大蒜愈伤组织诱导及增殖分化的影响因素,建立大蒜愈伤组织诱导、增殖及器官分化的培养体系。结果表明,适合大蒜愈伤组织诱导及增殖的培养基激素浓度及pH为2 mg/L NAA,2 mg/L 6-BA,1 mg/L 2,4-D和pH 5.8;苍山蒜愈伤组织出芽分化的最佳培养基激素浓度及pH为1 mg/L NAA,3 mg/L 6-BA,pH 5.8;苏联蒜愈伤组织出芽分化的最佳培养基激素浓度及pH为2 mg/L NAA,2 mg/L 6-BA,pH 6.1;苍山蒜和苏联蒜愈伤组织生根分化的最佳培养基激素浓度及pH均为1 mg/L NAA,pH 5.8,表明高浓度的2,4-D有利于大蒜愈伤组织的诱导,但并不利于其分化。

基于逆Leidenfrost效应的多孔地聚合物微球孔结构及pH缓冲性能

以水玻璃、矿渣粉为材料,基于逆Leidenfrost效应制备了多孔地聚合物微球,研究了其孔结构及pH缓冲性能.结果表明:改变水玻璃掺量和水固比可以调控多孔地聚合物微球的孔结构和pH缓冲性能;当水固比为1.0、水玻璃掺量由4%增大至8%时,微球的孔隙率、中位孔径和孔比表面积均减小,pH值波动范围为1.50~1.90;当水玻璃掺量为4%、水固比由1.0增大至1.2时,微球的孔隙率、中位孔径和孔比表面积均增大,pH值波动范围超过2.00;与双氧水直接发气法制备的多孔地聚合物相比,基于逆Leidenfrost效应制备的多孔地聚合物具有更好的pH缓冲性能和更高的OH-累积浸出量.

NaCl胁迫下pH值和氮素形态对狗牙根生长及钠钾离子调控的影响

以狗牙根〔Cynodon dactylon(Linn.)Pers.〕品种‘阳江’(‘Yangjiang’)为实验材料、2-(N-吗啡啉)乙磺酸(MES)为pH缓冲剂,采用水培法研究NaCl胁迫下pH值和氮素形态(铵态氮和硝态氮)对狗牙根生长和钠钾离子调控的影响。结果表明:处理1周后,若不添加MES,铵态氮处理组培养液的pH值下降到pH 4.0左右,而硝态氮处理组培养液的pH值则上升到pH 9.0左右;添加20 mmol·L^(-1)MES的铵态氮处理组培养液的pH值也下降到pH 4.0左右,而硝态氮处理组培养液的pH值则接近pH 7.0。与0 mmol·L^(-1)NaCl处理组相比,300 mmol·L^(-1)NaCl处理组狗牙根的枝条长度和枝条干质量显著(P<0.05)下降,而根长度、根干质量、根和叶中Na^(+)含量和Na^(+)/K^(+)比、钠钾选择性转运系数、叶Na^(+)和K^(+)的分泌量及分泌物Na^(+)/K^(+)比总体上显著升高。300 mmol·L^(-1)NaCl胁迫下,硝态氮处理组狗牙根的枝条长度、根长度、根干质量、根冠比、根中Na^(+)含量总体上显著高于铵态氮处理组,而叶中Na^(+)和K^(+)含量及Na^(+)/K^(+)比、叶Na^(+)和K^(+)的分泌量明显低于铵态氮处理组。300 mmol·L^(-1)NaCl胁迫下,20 mmol·L^(-1)MES处理组狗牙根的多数生长指标显著高于0 mmol·L^(-1)MES处理组,而根和叶中Na^(+)和K^(+)含量及Na^(+)/K^(+)比、钠钾选择性转运系数在0和20 mmol·L^(-1)MES处理组间的差异不显著。三因素方差分析结果表明:3个因子的单一和交互作用对多数生长指标、叶中Na^(+)含量和泌盐量相关指标的影响具有统计学意义。研究结果显示:硝态氮能缓解NaCl胁迫对狗牙根的伤害,而用MES缓冲根际酸碱环境对NaCl胁迫下狗牙根生长有一定的促进作用,因此,施用硝态氮或添加MES均有利于提高狗牙根的抗盐性。

基于二维相关红外光谱对pH值影响大豆分离蛋白二级结构含量的快速分析

为满足不同种类食品对大豆分离蛋白(soybean protein isolate,SPI)不同功能性的需求,本研究利用红外光谱快速采集70组不同pH值处理后SPI的数据,探讨pH值变化对SPI结构含量的影响。使用均值中心化、多元散射校正、标准正态变量变换和归一化算法对红外光谱数据进行预处理,基于二维相关红外光谱提取特征波段,再利用偏最小二乘(partial least square,PLS)法和算术优化算法-随机森林(arithmetic optimization algorithm-random forests,AOA-RF)建立不同pH值条件下SPI结构及含量的预测模型。结果表明,经均值中心化和多元散射校正结合处理后,α-螺旋、β-折叠、β-转角和无规卷曲模型的相对标准偏差分别为1.29%、1.60%、1.37%、7.28%,两者结合对光谱数据的预处理效果最佳。预测α-螺旋和β-折叠含量最优模型为AOA-RF(特征波段),校正集决定系数为0.9350和0.9266,预测集决定系数为0.8568和0.8701;预测β-转角和无规卷曲含量最优模型为PLS(特征波段),校正集决定系数为0.9154和0.8817,预测集决定系数为0.8913和0.7843。本研究结果可为工业生产过程中产品质量快速检测和工艺条件控制提供理论支撑。

超声辅助pH值偏移处理对大豆亲脂蛋白结构和功能性质的影响及其相关性分析

为探究超声辅助pH值偏移对大豆亲脂蛋白(soybean lipophilic proteins,SLP)结构和功能性的影响,将分离提取的SLP在超声(240 W、20 min)及极端pH值(pH 1或12)条件下进行改性。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、游离巯基含量、傅里叶变换红外光谱、荧光光谱等对不同处理的SLP一级、二级、三级结构进行表征,并对SLP功能性质进行分析。结果表明:超声辅助pH 12偏移处理下SLP结构-功能性改变最大,平均粒径由5245.33 nm降低至447.13 nm,ζ-电位值由-5.95 mV下降至-18.53 mV,游离巯基含量下降,α-螺旋相对含量增加,荧光光谱发生蓝移,荧光强度降低;同时溶解度由9.84%上升至92.04%,乳化性、起泡性提高。因此超声和pH值偏移处理对SLP结构性质和功能性质具有协同作用,且结构和功能性质相关性较密切。