Novel umami peptides from two Termitomyces mushrooms and molecular docking to the taste receptor T1R1/T1R3

Wild edible Termitomyces mushrooms are popular in Southwest China and umami is important flavor qualities of edible mushrooms.This study aimed to understand the umami taste of Termitomyces intermedius and Termitomyces aff.bulborhizus.Ten umami peptides from aqueous extracts were separated using a Sephadex G-15 gel filtration chromatography.The intense umami fraction was evaluated by both sensory evaluation and electronic tongue.They were identified as KLNDAQAPK,DSTDEKFLR,VGKGAHLSGEH,MLKKKKLA,SLGFGGPPGY,TVATFSSSTKPDD,AMDDDEADLLLLAM,VEDEDEKPKEK,SPEEKKEEET and PEGADKPNK.Seven peptides,except VEDEDEKPKEK,SPEEKKEEET and PEGADKPNK were selectively synthesized to verify their taste characteristics.All these 10 peptides had umami or salt taste.The 10 peptides were conducted by molecular docking to study their interaction with identified peptides and the umami taste receptor T1R1/T1R3.All these 10 peptides perfectly docked the active residues in the T1R3 subunit.Our results provide theoretical basis for the umami taste and address the umami mechanism of two wild edible Termitomyces mushrooms.

Three novel umami peptides derived from the alcohol extract of the Pacific oyster(Crassostrea gigas):identification,characterizations and interactions with T1R1/T1R3 taste receptors

Oyster(Crassostrea gigas),the main ingredient of oyster sauce,has a strong umami taste.In this study,three potential umami peptides,FLNQDEEAR(FR-9),FNKEE(FE-5),and EEFLK(EK-5),were identified and screened from the alcoholic extracts of the oyster using nano-HPLC-MS/MS analysis,i Umami-Scoring Card Method(i Umami-SCM)database and molecular docking(MD).Sensory evaluation and electronic tongue analysis were further used to confirm their tastes.The threshold of the three peptides ranged from 0.38 to 0.55 mg/m L.MD with umami receptors T1R1/T1R3 indicated that the electrostatic interaction and hydrogen bond interaction were the main forces involved.Besides,the Phe592 and Gln853 of T1R3 were the primary docking site for MD and played an important role in umami intensity.Peptides with two Glu residues at the terminus had stronger umami,especially at the C-terminus.These results contribute to the understanding of umami peptides in oysters and the interaction mechanism between umami peptides and umami receptors.

Role of bitter contributors and bitter taste receptors:a comprehensive review of their sources,functions and future development

Bitterness,one of the 5“basic tastes”,is usually undesired by humans.However,abundant literature reported that bitter fruits and vegetables have beneficial health effects due to their bitter contributors.This review provided an updated overview of the main bitter contributors of typical bitter fruits and vegetables and their health benefits.The main bitter contributors,including phenolics,terpenoids,alkaloids,amino acids,nucleosides and purines,were summarized.The bioactivities and wide range of beneficial effects of them on anti-cancers,anti-inflammations,anti-microbes,neuroprotection,inhibiting chronic and acute injury in organs,as well as regulating behavior performance and metabolism were reported.Furthermore,not only did the bitter taste receptors(taste receptor type 2 family,T2Rs)show taste effects,but extra-oral T2Rs could also be activated by binding with bitter components,regulating physiological activities via modulating hormone secretion,immunity,metabolism,and cell proliferation.This review provided a new perspective on exploring and explaining the nutrition of bitter foods,revealing the relationship between the functions of bitter contributors from food and T2Rs.Future trends may focus on revealing the possibility of T2Rs being targets for the treatment of diseases,exploring the mechanism of T2Rs mediating the bioactivities,and making bitter foods more acceptable without getting rid of bitter contributors.

Umami taste components in chicken-spices blends and potential effect of aroma on umami taste intensity

In this study,umami taste intensity(UTI)and umami taste components in chicken breast(CB)and chickenspices blends were characterized using sensory and instrumental analysis.Our main objective was to assess the aroma-umami taste interactions in different food matrices and reconcile the aroma-taste perception to assist future product development.The impact of key aroma,including vegetable-note"2-pentylfuran",meaty"methional",green"hexanal",and spicy-note-estragole and caryophyllene"on UTI was evaluated in monosodium glutamate and chicken extract.We found that spices significantly decreased UTI and umami taste components in CB.Interestingly,the perceptually similar odorants and tastants exhibited the potential to enhance UTI in food matrices.Methional was able to increase the UTI,whereas spicy and green-note components could reduce the UTI significantly.This information would be valuable to food engineers and formulators in aroma selection to control the UTI perceived by consumers,thus,improving the quality and acceptability of the chicken products.

Studies of the Variability of Primary Metabolites in the Epicarp, Mesocarp and Seed of Dacryodes edulis Fruit at Taste Maturity

The fruits of Dacryodes edulis are rich in biologically active substances, which makes them of great interest in terms of validation. In this study, we targeted the primary metabolites in the epicarp, the mesocarp and the seed of the fruit of Dacryodes edulis at taste maturity, which were selected for their nutritional quality and its appreciation throughout the Gulf of Guinea area, which is very popular because of its large size, texture and special taste. The evaluation of total carbohydrates, total lipids and soluble proteins in the epicarp, mesocarp and seed of the fruit at taste maturity was made from spectrophotometer measurements. The overall analysis of the results of the present study shows that total carbohydrates, total lipids and proteins accumulate more in the seed with respectively 251.33 ± 1.15 mg/g DM;9.92 ± 0.201 mg/g DM and 55.075 ± 0.024 mg/g DM. Likewise, the results indicate low concentrations of total carbohydrates and total lipids in the epicarp with respectively 245 ± 1 mg/g DM and 4.77 ± 0.047 mg/g DM, on the other hand, it is the mesocarp which presents the lowest content of soluble proteins: 28.075 ± 3.231 mg/g DM. This variation could be linked to the nature of the compartment, more particularly to the storage location. This comparative study could lead to the valorization of the seed of the fruit of Dacryodes edulis for its richness in metabolites and arouse significant interest in nutrition.

First report of the histopathological effect of electrocautery using on the urethral taste rosea during glans penis injury by incision in rabbits

Objective:Currently,electrocautery devices have frequently been used in penile surgical procedures.We hypothesized that electrocautery using during penile surgical procedures may harm the taste rosea and the dorsal nerve of the penis or clitoris.Methods:Eighteen young age male New Zealand rabbits were studied:five in the control(Group I,n=5),five in the penile surgery without using electrocautery(sham group,Group II,n=5),eight in the monopolar cautery(study group,Group III,n=8)groups under general anesthesia.The animals were followed for 3 weeks and sacrificed.Penile tissue—pudendal nerve root complexes and dorsal root ganglion of sacral 3 level were examined using stereological methods.The results were compared statistically.Results:The live and degenerated taste bud-like structures and degenerated neuron densities of pudendal ganglia(mean±standard deviation,n/mm^(3))were estimated as 198±24/mm^(3),4±1/mm^(3),and 5±1/mm^(3) in Group I;8±3/mm^(3),174±21/mm^(3),and 24±7/mm^(3) in Group II;and 21±5/mm^(3),137±14/mm^(3),and 95±12/mm^(3) in Group III,respectively.Neurodegeneration of taste buds and pudendal ganglia was significantly different between groups.Conclusion:Intact spinal cord and normal parasympathetic and thoracolumbar sympathetic networks are crucial for human sexual function.The present study indicates that the glans penis injury by using electrocautery may lead to pudendal ganglia degeneration.Iatrogenic damage to taste rosea and retrograde degeneration of the pudendal nerve may be the cause of sexual dysfunction responsible mechanism.

Genetic mutation of Tas2r104/Tas2r105/Tas2r114 cluster leads to a loss of taste perception to denatonium benzoate and cucurbitacin B

Background:Bitter taste receptors(Tas2rs)are generally considered to sense various bitter compounds to escape the intake of toxic substances.Bitter taste receptors have been found to widely express in extraoral tissues and have important physiological functions outside the gustatory system in vivo.Methods:To investigate the physiological functions of the bitter taste receptor cluster Tas2r106/Tas2r104/Tas2r105/Tas2r114 in lingual and extraoral tissues,multiple Tas2rs mutant mice and Gnat3 were produced using CRISPR/Cas9 gene-editing technique.A mixture containing Cas9 and sgRNA mRNAs for Tas2rs and Gnat3 gene was microinjected into the cytoplasm of the zygotes.Then,T7EN1 assays and sequencing were used to screen genetic mutation at the target sites in founder mice.Quantitative real-time polymerase chain reaction(qRT-PCR)and immunostaining were used to study the expression level of taste signaling cascade and bitter taste receptor in taste buds.Perception to taste substance was also studied using twobottle preference tests.Results:We successfully produced several Tas2rs and Gnat3 mutant mice using the CRISPR/Cas9 technique.Immunostaining results showed that the expression of GNAT3 and PLCB2 was not altered in Tas2rs mutant mice.But qRT-PCR results revealed the changed expression profile of m Tas2rs gene in taste buds of these mutant mice.With two-bottle preference tests,these mutant mice eliminate responses to cycloheximide due to genetic mutation of Tas2r105.In addition,these mutant mice showed a loss of taste perception to quinine dihydrochloride,denatonium benzoate,and cucurbitacin B(CuB).Gnat3-mediated taste receptor and its signal pathway contribute to CuB perception.Conclusions:These findings implied that these mutant mice would be a valuable means to understand the biological functions of TAS2Rs in extraoral tissues and investigate bitter compound-induced responses mediated by these TAS2Rs in many extraoral tissues.

Ranking academic institutions based on the productivity,impact,and quality of institutional scholars

Purpose:The quantitative rankings of over 55,000 institutions and their institutional programs are based on the individual rankings of approximately 30 million scholars determined by their productivity,impact,and quality.Design/methodology/approach:The institutional ranking process developed here considers all institutions in all countries and regions,thereby including those that are established,as well as those that are emerging in scholarly prowess.Rankings of individual scholars worldwide are first generated using the recently introduced,fully indexed ScholarGPS database.The rankings of individual scholars are extended here to determine the lifetime and last-five-year Top 20 rankings of academic institutions over all Fields of scholarly endeavor,in 14 individual Fields,in 177 Disciplines,and in approximately 350,000 unique Specialties.Rankings associated with five specific Fields(Medicine,Engineering&Computer Science,Life Sciences,Physical Sciences&Mathematics,and Social Sciences),and in two Disciplines(Chemistry,and Electrical&Computer Engineering)are presented as examples,and changes in the rankings over time are discussed.Findings:For the Fields considered here,the Top 20 institutional rankings in Medicine have undergone the least change(lifetime versus last five years),while the rankings in Engineering&Computer Science have exhibited significant change.The evolution of institutional rankings over time is largely attributed to the recent emergence of Chinese academic institutions,although this emergence is shown to be highly Field-and Discipline-dependent.Practical implementations:Existing rankings of academic institutions have:(i)often been restricted to pre-selected institutions,clouding the potential discovery of scholarly activity in emerging institutions and countries;(ii)considered only broad areas of research,limiting the ability of university leadership to act on the assessments in a concrete manner,or in contrast;(iii)have considered only a narrow area of research for comparison,diminishing the broader applicability and impact of the assessment.In general,existing institutional rankings depend on which institutions are included in the ranking process,which areas of research are considered,the breadth(or granularity)of the research areas of interest,and the methodologies used to define and quantify research performance.In contrast,the methods presented here can provide important data over a broad range of granularity to allow responsible individuals to gauge the performance of any institution from the Overall(all Fields)level,to the level of the Specialty.The methods may also assist identification of the root causes of shifts in institution rankings,and how these shifts vary across hundreds of thousands of Fields,Disciplines,and Specialties of scholarly endeavor.Originality/value:This study provides the first ranking of all academic institutions worldwide over Fields,Disciplines,and Specialties based on a unique methodology that quantifies the productivity,impact,and quality of individual scholars.

基于学习活动观的小学英语课堂TASTE教学模式探究

针对当前部分教师对于如何在小学英语课堂上落实学习活动观的困惑,文章通过大量案例研究提炼出一种基于学习活动观的TASTE教学模式。TASTE教学倡导教师基于单元整体视域,根据单元主题与单元目标,确立课时目标,以目标为导向设计连续性话题,并以连续性话题为支点,建构以探究答案、共享表现、真实表达为主要内容的活动流程,从而在课堂上落实学习理解、应用实践、迁移创新等三类活动。

Identification of key taste components in Baccaurea ramiflora Lour.fruit using non-targeted metabolomics

Among the numerous fruit species of Baccaurea ramiflora Lour.,‘LR’(white flesh)and‘BR’(pink flesh)are two kinds of local strains with high edibility.In order to study the metabolic causes of taste differences,we performed the non-targeted metabonomics analysis of‘LR’and‘BR’using LC-MS/MS.541 metabolites were totally identified,and 45 kinds of metabolites(carbohydrates,fatty acids,flavonoids and terpenoids,etc.)were different between the two strains.The results indicate L-sorbose,D-(+)-glucose,citric acid,L-phenylalanine and oleamide,α-eleostearic acid were the main primary metabolites.The significant difference existed in pathways of unsaturated fatty acids between the studied two strains by pathway enrichment analysis.The results demonstrate that the different in composition,as well as the abundance of primary and secondary metabolites may be the potential causes of taste differences,which provides a new insight into the possible metabolic factors setting off the changing taste of B.ramiflora.

Discovery of the relationship between bitter taste and bitter flavor (efficacy) based on hTAS2Rs

Objective:To explore the relationship between bitter taste and bitter flavor(efficacy),their character-istics were analyzed at the target and pharmacodynamic points.Methods:Compounds with bitter receptor activity were obtained by high-throughput screening models of the human bitter taste receptors(hTAS2Rs),which were used to analyze bitter taste.The efficacy of anti-asthma medications was used as an example to research bitter flavor(efficacy).The pharmacological effects of bitter taste and bitter flavor(efficacy)were classified according to the functional modules.The coverage for the same targets or pharmacological effects in the overall protein interaction network(PIN)of bitter taste and bitter flavor(efficacy)was analyzed to reveal their relationship.The effect of the compound polydatin with anti-asthma activation on hTAS2R14 was studied to verify the reliability of the aforementioned idea.Results:A total of 121 Chinese materia medica(CMM)compounds that activate hTAS2R10,hTAS2R14,and hTAS2R49 were obtained.The analysis results indicated that 108 same targets for bitter taste and bitter flavor(efficacy)were obtained,accounting for 13.9%in the PIN of bitter taste and 72.5%in the PIN of bitter flavor(efficacy).The pharmacological effects shared by bitter taste and bitter flavor(efficacy)accounted for 79%of the PIN of bitter taste and 81%of the PIN of bitter flavor(efficacy).The activating effect of the anti-asthma compound polydatin on hTAS2R14 was dose-dependent with EC 50 of 4.3 m M.Conclusion:In this study,the relationship between bitter taste and bitter flavor(efficacy)has been demonstrated from the target and pharmacodynamic points,which are based on hTAS2Rs and anti-asthma effect.Bitter taste and bitter flavor(efficacy)exhibited a high correlation.This study provides a theoretical and scientific basis for the hypothesis that“the property theory of CMM is the clinical pharmacodynamics of CMM.”

Untargeted UHPLC-Q-Exactive-MS-based metabolomics reveals associations between pre-and post-cooked metabolites and the taste quality of geographical indication rice and regular rice

Geographical indication(GI)rice refers to the rice of specific geographical origin,which tends to have a good taste quality and a high commodity price.Rice is favored for its soft texture and chewiness after cooking.However,GI rice is also plagued by rice fraud.Understanding the reasons for the excellent taste quality of GI rice and identifying its geographical origin can help maintain the stability of the rice market and promote the development of the rice industry.In this study,we determined the taste quality of rice.Untargeted metabolomics based on UHPLC-Q-Exactive-MS was used to identify metabolites in GI and regular rice before and after cooking.Our findings suggested that GI rice showed lower protein and amylose content,resulting in higher starch gelatinization properties and taste quality.This study identified 520 metabolites,among which 142 and 175 were significantly different between GI and regular rice,before and after cooking,respectively.The increased variety of metabolites after cooking was significantly negatively correlated with the taste quality of rice.GI rice was lower in amino acids and lipid metabolite content before and after cooking,which may be the reason for the excellent taste quality.Through linear discriminant analysis,we found that the differential metabolites of rice after cooking were more accurate in discriminating rice from different geographic origins,up to 100%.This work gained new insights into the metabolites of GI rice,which explains its excellent taste quality.The rice metabolites after cooking could be used for more accurate geographical identification of rice.

Dry matter production and panicle characteristics of high yield and good taste indica hybrid rice varieties

Indica hybrid rice(Oryza sativa) production aims to achieve two crucial targets: high yield and good taste. This study selected three types of indica hybrid rice according to grain yield and taste value, including high yield and good taste(HYGT), low yield and good taste(LYGT), and high yield and poor taste(HYPT), to analyze yield components,corresponding growth characteristics, and rice taste quality. When values were averaged across varieties and years,there were almost no differences in taste value between HYGT and LYGT;HYGT showed a significant increase in yield,owing to a higher number of panicles and spikelets per panicle, with a respective increment of 16.2 and 20.6%. The higher grain yield of HYGT compared with LYGT was attributed to three key factors: a higher leaf area index(LAI) during heading, a higher ratio of grain to leaf, and a higher biomass accumulation at maturity. HYGT and HYPT achieved similar high yields;however, HYGT had more panicle numbers and lower grain weight. In addition, HYGT showed a significantly higher taste value than HYPT, attributed to its significantly lower protein and amylose contents, with reductions of 8.8and 15.7%, respectively. Lower protein and amylose contents might be caused by a proper matter translocation from vegetative organs to panicle. This study suggested that reasonable panicle characteristics and translocation efficiency from vegetative organs to panicle during heading to maturity are the key factors in balancing yield and rice taste quality.These results will provide valuable insights for rice breeders to improve the grain yield and quality of indica hybrid rice.

CIIS Holds the 20th China-US Young Scholars’Dialogue

From November 7 to 10,the China Institute of International Studies(CIIS)held the 20th China-US Yong Scholars’Dialogue,with the theme of“Finding the Right Way for China and the US to Get Along in the New Era:Opportunities and Challenges.”CIIS President Chen Bo delivered the opening remarks,and Vice President Liu Qing delivered the closing speech.

Alternation and Evolution of the Fables of Pre-Qin Scholars Along With the Contextual Changes

The fables of Pre-Qin scholars occupied an important position in the history of the development of Chinese culture,thoughts,and literature,hence had profound and extensive influence on later generations.As a kind of carrier of thoughts,the fables of the Pre-Qin scholars were not immutable and frozen,for they have been influenced by various aspects in the process of transmitting and recognizing.This article attempts to study the evolution of the function,expression,and connotation of the fables of the Pre-Qin scholars.

Study on the Influencing Factors of Chemotherapeutic-Related Taste Changes in Cancer Patients

Objective: To investigate the current situation of chemotherapy-related taste changes of cancer patients in Jingzhou area, and analyze the influencing factors of chemotherapy-related taste changes of cancer patients. Methods: In this study, 233 patients with malignant tumors who were confirmed by pathological examination and expected survival time of more than 6 months after admission to a tertiary general hospital in Jingzhou from January 2018 to October 2018 were selected by convenience sampling method. The Chinese version of The chemotherapy-induced Taste Alternation Scale (CiTAS) was used to investigate the baseline data and occurrence status, and multiple regression analysis was used to explore the influencing factors. Results: In this study, 171 tumor patients experienced chemotherapy related taste changes, accounting for 73.4% (171/233);The vast majority of chemotherapy patients have different types and severity of taste changes;Multiple regression analysis showed that the duration of chemotherapy, the number of consecutive days of chemotherapy, and dry mouth were the main influencing factors for chemotherapy related taste changes in cancer patients (p Conclusion: Nursing personnel should pay attention to the occurrence of chemotherapy-related taste changes in tumor patients, and provide predictive nursing interventions to improve their taste experience for tumor patients who have a long course of chemotherapy, many consecutive days of chemotherapy, or have dry mouth conditions.

基于自主出版平台服务一流科技期刊建设的创新发展路径及应用探索——以聚光学术(Lighthouse Scholar)平台为例

中国的世界一流科技期刊建设对象应包含中文刊和英文刊,这是掌握国际学术话语权的基础。中国已经成为论文发表大国,科技期刊发展的数量和质量也在不断提升,但大部分科技期刊需依托第三方出版平台完成论文的投稿、评审及发表等工作,容易造成出版“卡脖子”问题。为了能在自主办刊上取得一些突破,中山大学中山眼科中心通过加强出版人才建设、夯实技术基础等措施,自主研发符合国情、具有医学特色的出版平台,服务中文期刊和英文期刊的全流程出版。就中山大学中山眼科中心基于自主出版平台服务自主办刊过程的一些探索进行总结分析,以期为中国科技期刊发展提供可借鉴的办刊经验。

A Scholar of Dignity:Remembering Peter Luh

It was a shock and disbelief to learn of Peter's death last December.To me,he was so fit in his figure,so healthy in his lifestyle,so mild and mindful in his social behavior,and so devout in his religious belief,......,I had expected a long and happy life for him,and planned to join his 80th or even 100th birthday celebration.

ScholarSFX与Google Scholar的本地化

Google Scholar的推出吸引了越来越多的学术研究人员。本文详细介绍了图书馆链接计划的运作模式和SFX技术的原理。重点介绍了免费链接解析服务器ScholarSFX的配置方法,以及它在浙江大学图书馆的应用,最后对Google Scholar图书馆链接的应用情况进行了总结。

资源利用与开发的范例——弗吉尼亚大学图书馆的“Scholars' Lab”

"Scholars' Lab"是一个专为弗吉尼亚大学人文社科专业教师和学生利用图书馆数字资源、寻求专家帮助、进行协同合作与创新研究的场所,其主要理念是图书馆资源与专家学者的有机融合,促进创新项目开展,提升研究层次。实验室由弗吉尼亚大学图书馆的数字化学术研究小组专家学者组成。文章介绍了"Scholars' Lab"的基本概况、服务内容及奖励措施,基于案例分析概括该实验室的几个鲜明特点,旨在为国内大学图书馆创新学科化服务,开发馆藏资源提供参考与帮助。