Odors
Rhinomanometry
Olfaction Disorders
Major odorants released as urinary volatiles by urinary incontinent patients. (1/8)
(+info)Metal oxide gas sensor drift compensation using a dynamic classifier ensemble based on fitting. (2/8)
(+info)Characterization of aroma-active compounds in dry flower of Malva sylvestris L. by GC-MS-O analysis and OAV calculations. (3/8)
In this study, the aroma-active compounds in the dried flower of Malva sylvestris L. were extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS), and gas chromatography-olfactometry (GC-O) and aroma extraction dilution analysis (AEDA). A light yellow oil with a sweet odor was obtained with a percentage yield of 0.039% (w/w), and 143 volatile compounds (89.86%) were identified by GC-MS. The main compounds were hexadecanoic acid (10.1%), pentacosane (4.8%) and 6,10,14-trimethyl-2-pentadecanone (4.1%). The essential oil consisted mainly of hydrocarbons (25.40%) followed by, alcohols (18.78%), acids (16.66%), ethers (5.01%) ketones (7.28%), esters(12.43%), aldehydes (2.30%) and others (2.00%). Of these compounds, 20 were determined by GC-O and AEDA, to be odor-active (FD (flavor dilution) factor >/= 1). beta-Damascenone (FD = 9, sweet), phenylacetaldehyde (FD = 8, floral, honey-like) and (E)-beta-ocimene (FD = 8, spicy) were the most intense aroma-active compounds in M. sylvestris. In order to determine the relative contribution of each of the compounds to the aroma of M. sylvestris, odor activity values (OAVs) were used. beta-Damascenone had the highest odor activity values (OAV) (50,700), followed by (E)-beta-ionone (15,444) and decanal (3,510). In particular, beta-damascenone had a high FD factors, and therefore, this compound was considered to be the main aroma-active components of the essential oil. On the basis of AEDA, OAVs, and sensory evaluation results, beta-damascenone is estimated to be the main aroma-active compound of the essential oil. (+info)Comparison of volatile compounds with characteristic odor in flowers and leaves of nojigiku (Chrysanthemum japonense). (4/8)
The aim of the present study was to investigate the essential oils isolated from flower and leaf in order to get insight into similarities and differences as to their aroma-active composition. The essential oil obtained from the two parts were analyzed by gas chromatography-mass spectrometry and gas chromatography olfactometry (GC-O). Flower and leaf oils, 38 and 36 constituents, representing 96.4 and 91.0% of the total oil composition, respectively, were identified. The main compounds in flower oil were camphor (47.64%), bornyl acetate (11.87%), and nojigiku alcohol (6.29%), whereas those in leaf oil were camphor (39.14%), nojigiku alcohol (10.76%) and gamma-muurolene (7.02%). 13 Aroma-active compounds were identified by GC-O analysis in flower oil and 12 in leaf oil. The main aroma-active compounds in flower oil were camphor (camphor, FD (flavor dilution) = 7, OAV (odor active value) = 136913), bornyl acetate (camphor, FD = 6, OAV = 113711), and beta-caryophyllene (spicy, FD = 5, OAV = 116480). In leaf oil, the main aroma-active compounds were camphor (camphor, FD = 7, OAV = 106784), nojigiku alcohol (camphor, FD = 5, OAV = not determined), and beta-caryophyllene (spicy, FD = 6, OAV = 526267). (+info)Evaluation of volatiles from Ampelopsis brevipedunculata var. heterophylla using GC-olfactometry, GC-MS and GC-pulsed flame photometric detector. (5/8)
Ampelopsis brevipedunculata var. heterophylla is extensively cultivated in Asia, and the dried leaves and branches have a characteristic odor and have been used as a tea. To investigate the odorants contributing to the characteristic odor of A. brevipedunculata var. heterophylla, the aroma extraction dilution analysis method was performed through gas chromatography olfactometry. In addition, volatile sulfur compounds were evaluated using pulsed flame photometric detector. As a result, 86 compounds were identified in the oils of leaves and 78 in branches, accounting for 80.0% and 68.3%, respectively, of the compounds identified. The main compounds in the essential oil of leaves were palmitic acid (12.5%), phenylacetaldehyde (4.1%) and hexahydrofarnesyl acetone (3.9%). On the other hand, the essential oil of branches contained palmitic acid (12.7%), terpinen-4-ol (4.4%) and alpha-cadinol (3.7%). The total number of odor-active compounds identified in the leaf and branch oils was 39. The most odorous compounds of leaves and branches of A. brevipedunculata var. heterophylla were (E, Z)-2,6-nonadienal (melon, green odor), (E)-2-nonenal (grassy odor), phenylacetaldehyde (honey-like) and (E)-linalool oxide (woody odor). (+info)Volatile components of essential oil from cultivated Myrica gale var. tomentosa and its antioxidant and antimicrobial activities. (6/8)
Aromatic components in the essential oil prepared from the leaves of cultivated Myrica gale var. tomentosa were compared with those from oil derived wild plants by using gas chromatography-mass spectroscopy (GC/MS). We found that essential oils from both the wild and cultivated plants contained similar aromatic components such as beta-elemenone, selina 3,7(11)-diene, myrcene, limonene, cymene, 1,8-cineole, and beta-pinene, but the content ratio of the oil was significantly different, which might yield differences in the aromatic properties. The aroma impact components of the essential oils were also determined using GC/MS-Olfactometry (GC/MS-O) and aroma extract dilution analysis. Eight aromatic compounds, including linalool, limonene, and 1,8-cineole, were shown to contribute to the aromatic properties of cultivated M. gale var. tomentosa. The strongest aromatic note was defined as linalool, followed by limonene, 1,8-cineole, and beta-elemenone. The essential oil, ethanol (EtOH), 1,3-butylene glycol (BG), and 1,3-propanediol (PD) extracts prepared from the leaves of cultivated M. gale var. tomentosa also showed antioxidant and antimicrobial activities, that is, they demonstrated scavenger activity against hydroxyl and superoxide radicals in the aqueous phase, and showed inhibitory effects on lipid peroxidation. The essential oil extracts also exhibited antimicrobial activity against gram-positive bacteria, with the lowest minimum inhibitory concentration value against Bacillus subtilis. In conclusion, the essential oil and solvent extracts from cultivated M. gala var. tomentosa have a potential for utilization as food and cosmetic ingredients. (+info)Sensory and instrumental analysis of medium and long shelf-life Charentais cantaloupe melons (Cucumis melo L.) harvested at different maturities. (7/8)
(+info)Gas chromatography analysis with olfactometric detection (GC-O) as a useful methodology for chemical characterization of odorous compounds. (8/8)
(+info)Olfactometry is a method used to measure the sensitivity of a person's sense of smell. It involves presenting the subject with a series of odors at different concentrations and asking them to identify or rate the intensity of the odor. The results are then used to calculate the subject's olfactory threshold, which is the lowest concentration at which they can detect the presence of an odor. Olfactometry is often used in research, occupational health, and clinical settings to assess olfactory function and diagnose smell disorders.
In the context of medicine, "odors" refer to smells or scents that are produced by certain medical conditions, substances, or bodily functions. These odors can sometimes provide clues about underlying health issues. For example, sweet-smelling urine could indicate diabetes, while foul-smelling breath might suggest a dental problem or gastrointestinal issue. However, it's important to note that while odors can sometimes be indicative of certain medical conditions, they are not always reliable diagnostic tools and should be considered in conjunction with other symptoms and medical tests.
Rhinomanometry is a medical diagnostic procedure that measures the pressure and flow of air through the nasal passages. It is used to assess the nasal airway resistance and function, and can help diagnose and monitor conditions such as nasal congestion, deviated septum, sinusitis, and other disorders that affect nasal breathing.
During the procedure, a small catheter or mask is placed over the nose, and the patient is asked to breathe normally while the pressure and airflow are measured. The data is then analyzed to determine any abnormalities in nasal function, such as increased resistance or asymmetry between the two sides of the nose.
Rhinomanometry can be performed using either anterior or posterior methods, depending on whether the measurement is taken at the entrance or exit of the nasal passages. The results of the test can help guide treatment decisions and assess the effectiveness of therapies such as medications or surgery.
In medical terms, the sense of smell is referred to as olfaction. It is the ability to detect and identify different types of chemicals in the air through the use of the olfactory system. The olfactory system includes the nose, nasal passages, and the olfactory bulbs located in the brain.
When a person inhales air containing volatile substances, these substances bind to specialized receptor cells in the nasal passage called olfactory receptors. These receptors then transmit signals to the olfactory bulbs, which process the information and send it to the brain's limbic system, including the hippocampus and amygdala, as well as to the cortex. The brain interprets these signals and identifies the various scents or smells.
Impairment of the sense of smell can occur due to various reasons such as upper respiratory infections, sinusitis, nasal polyps, head trauma, or neurodegenerative disorders like Parkinson's disease and Alzheimer's disease. Loss of smell can significantly impact a person's quality of life, including their ability to taste food, detect dangers such as smoke or gas leaks, and experience emotions associated with certain smells.
Olfaction disorders, also known as smell disorders, refer to conditions that affect the ability to detect or interpret odors. These disorders can be categorized into two main types:
1. Anosmia: This is a complete loss of the sense of smell. It can be caused by various factors such as nasal polyps, sinus infections, head injuries, and degenerative diseases like Alzheimer's and Parkinson's.
2. Hyposmia: This is a reduced ability to detect odors. Like anosmia, it can also be caused by similar factors including aging and exposure to certain chemicals.
Other olfaction disorders include parosmia, which is a distortion of smell where individuals may perceive a smell as being different from its original scent, and phantosmia, which is the perception of a smell that isn't actually present.
Sensory thresholds are the minimum levels of stimulation that are required to produce a sensation in an individual, as determined through psychophysical testing. These tests measure the point at which a person can just barely detect the presence of a stimulus, such as a sound, light, touch, or smell.
There are two types of sensory thresholds: absolute and difference. Absolute threshold is the minimum level of intensity required to detect a stimulus 50% of the time. Difference threshold, also known as just noticeable difference (JND), is the smallest change in intensity that can be detected between two stimuli.
Sensory thresholds can vary between individuals and are influenced by factors such as age, attention, motivation, and expectations. They are often used in clinical settings to assess sensory function and diagnose conditions such as hearing or vision loss.