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1.
Biosci Biotechnol Biochem ; 88(7): 798-803, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38702849

RESUMEN

Two colorimetric methods are used to determine the total polyphenol contents of tea, namely, "the Folin-Ciocalteu method," defined by the International Organization for Standardization, and the "iron tartrate method," specified in the Standard Tables of Food Composition in Japan. In this study, we compared the Folin-Ciocalteu and iron tartrate methods using green tea extracts. When comparing the 2 methods, the sum of the 4 major catechins measured using high-performance liquid chromatography (HPLC) was regarded as the standard value. The total polyphenol contents obtained using the Folin-Ciocalteu method were closer to the HPLC value than those obtained using the iron tartrate method. However, the iron tartrate method is adequate if the current official method is improved, that is, our results suggest that the coefficients appropriate for common green tea varieties, as well as the degree and duration of cover cultivation, in the official iron tartrate method must be considered.


Asunto(s)
Colorimetría , Extractos Vegetales , Polifenoles , , Polifenoles/análisis , Té/química , Colorimetría/métodos , Extractos Vegetales/análisis , Extractos Vegetales/química , Cromatografía Líquida de Alta Presión/métodos
2.
Biosci Biotechnol Biochem ; 88(6): 665-670, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38561637

RESUMEN

Bee pollen is an apicultural product collected by honeybees from flower stamens and used as a functional food worldwide. In the present study, we aim to elucidate the functions of Australian bee pollen. Australian bee pollen extracts and their main components were tested for catechol-O-methyltransferase (COMT) and monoamine oxidase B (MAOB) inhibitory activities. These enzymes are key neurotransmitters involved in Parkinson's disease and depression. Myricetin (5), tricetin (6), and luteolin (7) exhibited high COMT inhibitory activities (half maximal inhibitory concentration [IC50] = 23.3, 13.8, and 47.4 µM, respectively). In contrast, 5, 7, and annulatin (8) exhibited MAOB inhibitory activities (IC50 = 89.7, 32.8, and 153 µM, respectively). Quantitative analysis via high-performance liquid chromatography revealed that 5 was abundant in Australian bee pollen extracts. Our findings suggest that 5 contributes to the COMT and MAOB inhibitory activities of Australian bee pollen.


Asunto(s)
Inhibidores de Catecol O-Metiltransferasa , Inhibidores de la Monoaminooxidasa , Polen , Animales , Australia , Abejas , Catecol O-Metiltransferasa/metabolismo , Inhibidores de Catecol O-Metiltransferasa/farmacología , Monoaminooxidasa/metabolismo , Inhibidores de la Monoaminooxidasa/farmacología , Inhibidores de la Monoaminooxidasa/química , Polen/química
3.
J Exp Psychol Hum Percept Perform ; 49(10): 1296-1309, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37561528

RESUMEN

Vocal imitation plays a critical function in the development and use of both language and music. Previous studies have reported more accurate imitation for sung pitch than spoken pitch, which might be attributed to the structural differences in acoustic signals and/or the distinct mental representations of pitch patterns across speech and music. The current study investigates the interaction between bottom-up (i.e., acoustic structure) and top-down (i.e., participants' language and musical background) factors on pitch imitation by comparing speech and song imitation accuracy across four groups: English and Mandarin speakers with or without musical training. Participants imitated pitch sequences that were characteristic of either song or speech, derived from pitch patterns in English and Mandarin spoken sentences. Overall, song imitation was more accurate than speech imitation, and this advantage was larger for English than Mandarin pitch sequences, regardless of participants' musical and language experiences. This effect likely reflects the perceptual salience of linguistic tones in Mandarin relative to English speech. Music and language knowledge were associated with optimal imitation of different acoustic features. Musicians were more accurate in matching absolute pitch across syllables and musical notes compared to nonmusicians. By contrast, Mandarin speakers were more accurate at imitating fine-grained changes within and across pitch events compared to English speakers. These results suggest that different top-down factors (i.e., language and musical background) influence pitch imitation ability for different dimensions of bottom-up features (i.e., absolute pitch and relative pitch patterns). (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Música , Percepción del Habla , Humanos , Habla , Percepción de la Altura Tonal , Conducta Imitativa , Lenguaje , Estimulación Acústica
4.
Carbohydr Res ; 519: 108628, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35793587

RESUMEN

Starch is composed of two giant polymers of glucose-linked amylose and amylopectin but is not considered to have a branched structure with adjacent α-1,6-linkages (adjacent double branches). We previously discovered that the oligosaccharide DP6-1 contains adjacent double branches in sake, a Japanese rice wine. In this study, we analyzed the oligosaccharides generated from rice starch following porcine pancreatic α-amylase and glucoamylase digestion by hydrophilic interaction chromatography coupled with time-of-flight/mass spectrometry. We found that their elution times were identical to those of the oligosaccharides containing adjacent double branches observed in sake. Nuclear magnetic resonance (NMR) analysis confirmed that one of the oligosaccharides was identical to DP6-1. This indicates for the first time that adjacent double branches exist in the branching structure of starch. The adjacent double branches were estimated to be present at a ratio of approximately 1:100 of the total branching points in rice starch, suggesting that the contribution of the adjacent double branch to the entire structure of starch may be limited. Nonetheless, we found adjacent double branches in starch from rice, maize, wheat, and potato, which indicates that this novel branching pattern is universally present in starch.


Asunto(s)
Enzima Ramificadora de 1,4-alfa-Glucano , Oryza , Amilopectina/química , Amilosa/química , Glucano 1,4-alfa-Glucosidasa , Oligosacáridos/química , Almidón/química
5.
Psychol Res ; 85(5): 1934-1942, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32488598

RESUMEN

In the process of acquiring musical skills, such as playing the piano, we develop sensorimotor associations between motor movements and perception of pitch. Previous research suggests that these acquired associations are relatively inflexible and show limited generalizability to performance under novel conditions. The current study investigated whether piano training constrains the ability to generalize learning based on an unfamiliar (inverted) pitch mapping, using a transfer-of-training paradigm (Palmer and Meyer in Psychol Sci 11:63-68, 2000). Pianists and non-pianists learned a training melody by ear with normal (higher pitches to the right) or inverted (higher pitches to the left) pitch mapping. After training, participants completed a generalization test in which they listened to and then immediately reproduced four types of melodies that varied in their similarity to the melody used during training and were based on the same, a similar, an inverted, or a different pitch pattern. The feedback mapping during the generalization test matched training. Overall, pianists produced fewer errors and required fewer training trials than non-pianists. However, benefits of training were absent for pianists who trained with inverted feedback when they attempted to reproduce a melody with a different structure than the melody used for training. This suggests that piano experience may constrain one's ability to generalize learning that is based on novel sensorimotor associations.


Asunto(s)
Música , Percepción Auditiva , Humanos , Aprendizaje
6.
Carbohydr Polym ; 251: 116993, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33142564

RESUMEN

Sake, a traditional Japanese rice wine, contains various oligosaccharides (Sake oligosaccharides; SAOs) derived from rice starch. We previously found that SAOs reach a high degree of polymerization (DP). In this study, we developed a hydrophilic interaction liquid chromatography-time-of-flight/mass spectrometry (HILIC-TOF/MS) based analytical method to separate isomeric SAOs. Isomers of SAOs with DP = 6, 7, and 8, which were named DP6-1, DP7-1, DP8-1 and DP8-2, respectively, were purified from sake and their structures were determined by two-dimensional NMR spectroscopy. These were novel oligosaccharides containing two α-1, 6 bonded branches on an α-1, 4-linked glucose main chain. Interestingly, adjacent double α-1, 6 branches that have not been identified in starch, were found in DP6-1, DP7-1, and DP8-1, suggesting the presence of the branching pattern in starch. DP6-1 was poorly digested by fungal glucoamylase, and this may be attributed to its adjacent double branches at the non-reducing end.


Asunto(s)
Oligosacáridos/química , Vino/análisis , Conformación de Carbohidratos , Secuencia de Carbohidratos , Fermentación , Proteínas Fúngicas/metabolismo , Glucano 1,4-alfa-Glucosidasa/metabolismo , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Isomerismo , Japón , Espectrometría de Masas , Resonancia Magnética Nuclear Biomolecular , Oryza/química , Almidón/química
7.
J Agric Food Chem ; 68(5): 1419-1426, 2020 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-31888328

RESUMEN

Sake, the Japanese rice wine, contains a variety of oligosaccharides and glucosides produced by fungal enzymes during the brewing process. This study investigates the effect of knocking out the Aspergillus oryzae α-glucosidase (agdA) gene on the transglycosylation products in brewed sake. In addition to α-ethyl glucoside and α-glyceryl glucoside, the amount of two compounds that have molecular mass values similar to that of ethyl maltose decreased by agdA gene knockout. Both compounds were synthesized, in vitro, from maltose and ethanol with purified agdA. Nuclear magnetic resonance analysis identified the two compounds as ethyl α-maltoside and ethyl α-isomaltoside, respectively, which are novel compounds in sake as well as in the natural environment. Quantitative analysis of 111 commercially available types of sake showed that these novel compounds were widely present at concentrations of several hundred mg/L, suggesting that both of them are ones of the common glycosides in sake.


Asunto(s)
Bebidas Alcohólicas/microbiología , Aspergillus oryzae/enzimología , Proteínas Fúngicas/metabolismo , Glicósidos/metabolismo , alfa-Glucosidasas/metabolismo , Bebidas Alcohólicas/análisis , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Etanol/metabolismo , Fermentación , Proteínas Fúngicas/genética , Glicósidos/química , Glicosilación , Maltosa/metabolismo , Oryza/metabolismo , Oryza/microbiología , alfa-Glucosidasas/genética
8.
Stud Health Technol Inform ; 264: 1111-1115, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31438097

RESUMEN

BACKGROUND: Recent reports of some studies have described that the cognitive function of cancer patients often declines by a phenomenon designated as cancer related cognitive impairment (CRCI). For patients' decision-making, detecting CRCI is important. To do so, this study uses language-based CRCI screening to examine participants' language ability. OBJECTIVE: This study was conducted to ascertain whether a Natural Language Processing (NLP) based system can detect CRCI, or not. MATERIALS AND METHODS: We obtained materials of two types from cancer patients (n = 116): (1) speech samples on three topics, and (2) cognitive function level test scores from Hasegawa's Dementia Scale - Revised (HDS-R), a test used in Japan for dementia patients. The test is similar to the Mini-Mental State Examination. RESULTS AND DISCUSSION: Cancer patients with lower HDS-R scores showed a significantly lower Type Token Ratio (TTR). CONCLUSION: This result demonstrates the feasibility of the proposed speech-language-based CRCI screening method.


Asunto(s)
Disfunción Cognitiva , Demencia , Neoplasias , Humanos , Japón , Procesamiento de Lenguaje Natural
9.
Stud Health Technol Inform ; 264: 1629-1630, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31438264

RESUMEN

Recent studies have attributed impaired cognitive function in cancer patients, or Cancer Related Cognitive Impairment (CRCI), to various causes. CRCI screening is vital for guiding important decisions about treatment options. This study investigates the emotional Stroop-test-based CRCI screening, examining response time when naming the colors of negative emotional words. Cancer patients (n=17) participated in two tests: (1) the Stroop task; (2) State-Trait Anxiety Inventory. Results suggest that Stroop-based CRCI screening is feasible.


Asunto(s)
Disfunción Cognitiva , Neoplasias , Cognición , Emociones , Humanos , Test de Stroop
10.
J Biosci Bioeng ; 124(2): 171-177, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28433489

RESUMEN

A traditional Japanese alcoholic beverage, sake, contains several oligosaccharides, which are associated with the taste of sake; however, little is known about the specific molecular species and concentrations of oligosaccharides in sake. Here, we developed an analytical method using hydrophilic interaction liquid chromatography-time-of-flight/mass spectrometry (HILIC-TOF/MS) which successfully detects the oligosaccharides in sake. A series of oligosaccharides with successive degree of polymerization (DP) values up to 18 were identified in sake for the first time, which we have named sake oligosaccharides (SAOs). The concentrations of the SAOs with DP = 3-8 were estimated to be in the range of 200-2000 ppm. Quantitative analysis of 6 different sake samples for SAOs with DP=2-8 and the other saccharides showed that the amount of each SAO differs significantly among the sake samples. Enzymatic digestion analysis suggested that the SAOs are probably branched maltooligosaccharides in structure, which are resistant to ß-amylase.


Asunto(s)
Bebidas Alcohólicas/análisis , Oligosacáridos/química , Oryza/química , Carbohidratos/análisis , Cromatografía Liquida , Humanos , Japón , Espectrometría de Masas , Gusto
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