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Effect of inhalation of essential oil from Inula helenium L. root on electroencephalographic (EEG) activity of human
... It is well known that the inhalation of essential oils can produce positive psychological and physiological functions in humans by reducing mental stress, and increasing mind relaxation and cognitive functions via stimulation of the central nervous system [2][3][4]. Previous studies have also proved that fragrances from essential oils can influence the mental condition of human beings [3,[5][6][7][8][9][10]. In particular, the aromatic volatile components in essential oils, such as mono-and sesquiterpene hydrocarbons and their oxygenated derivatives, are mainly responsible for their characteristic fragrances. ...
... In the study, the AT value was significantly decreased in different brain regions, such as the frontal, temporal, parietal, and occipital regions during exposure to A. rugosa essential oil. Sowndhararajan et al. [9] also reported that absolute theta wave activity significantly decreased at the sites of FP1, FP2, F3, F4, T4, P3, and P4 during inhalation of the essential oil of Inula helenium root. In another study, AT wave activity significantly varied via left and right inhalation of aldehyde C10 odor when compared with inhalation via both nostrils [10]. ...
... In the case of the RT power spectrum, significant decreases were noticed in frontal, temporal, parietal, and occipital regions during exposure to A. rugosa essential oil. RT wave activity also decreased at the site during inhalation of Inula helenium root essential oil (at FP1, FP2, F3, and F4 regions) and essential oil from the twigs of A. koreana (at F4 and P4 regions) [7,9]. Kim et al. [8] reported that the RT spectrum markedly decreased in the FP1 and P4 regions during inhalation of black pepper essential oil. ...
Agastache rugosa (Korean mint) is an important medicinal and aromatic plant and its aerial parts have a pleasant fragrance. A. rugosa leaves are used as an ingredient in salads and soups for enhancing the aroma and taste of foods in Korea. However, there is no report on the influence of the aroma of A. rugosa on human psychophysiological activity. Therefore, the present study aimed to investigate the effect of exposure to the essential oil of Korean A. rugosa on human electroencephalographic (EEG) activity. The essential oil of A. rugosa was isolated using steam distillation extraction and its composition was determined by gas chromatography and mass spectrometry (GC–MS) analysis. In the EEG study, 38 healthy volunteers (19 men and 19 women) participated. The EEG readings were analyzed for 25 EEG indices from 29 electrodes placed on the scalp according to the international 10–20 system. The major component in the essential oil of A. rugosa was estragole (89.49%) followed by D-limonene (3.40%), menthone (1.80%), and pulegone (1.86%). In the EEG study, significant decreases in absolute theta (AT) and relative theta (RT) power spectra were observed during the exposure to A. rugosa essential oil when compared to that of no odor exposure. Whereas relative alpha (RA), relative slow alpha (RSA), spectral edge frequency 50% (SEF50), and spectral edge frequency 50% of alpha (ASEF) power spectra values significantly increased. These results reveal that the EEG power spectra changes incurred during the exposure to the essential oil of A. rugosa may be associated with the enhancement of freshness and concentration states of the human brain.
... In a study measuring EEG changes before and after inhaling I. helenium essential oil, showed that inhalation of the essential oil activates brain arousal [22]. Jung et al. [23] found a positive effect of the scent of Lavandula angustifolia on brain electrical activity in adult women with sleep disorders. ...
... This method records electrophysiological signals generated by brain activity by attaching a sensor to the surface of the scalp. The electrical signals mentioned correspond to the following frequency bands: delta (0-4 Hz), theta (4-8 Hz), alpha (8)(9)(10)(11)(12) and beta (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Human actions, thoughts, and emotions can alter the brain wave activity at different frequencies. ...
... This method records electrophysiological signals generated by brain activity by attaching a sensor to the surface of the scalp. The electrical signals mentioned correspond to the following frequency bands: delta (0-4 Hz), theta (4-8 Hz), alpha (8-12 Hz) and beta (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). Human actions, thoughts, and emotions can alter the brain wave activity at different frequencies. ...
This study investigated the effects of olfactory stimulation with aroma oils on the psychophysiological responses in women. Ten aromatic oils (lavender, rosemary, rose, eucalyptus, jasmine, geranium, chamomile, clary sage, thyme, and peppermint) were used on 23 women aged between 20 and 60 years. They inhaled the scent for 90 s through a glass funnel attached to their lab apron, 10 cm below their nose, while the pump was activated. Electroencephalography, blood pressure, and pulse rate were measured before and during inhalation of the aroma oils. The relative alpha (RA) power spectrums indicating relaxation and resting state of the brain significantly increased when lavender, rosemary, eucalyptus, jasmine, chamomile, clary sage, and thyme oils were inhaled compared to those of before olfactory stimulation. The ratio of alpha to high beta (RAHB), an indicator of brain stability and relaxation, significantly increased when rosemary, jasmine, clary sage, and peppermint oils were inhaled. The relative low beta (RLB) power spectrum, an indicator of brain activity in the absence of stress, significantly increased when stimulated with lavender, rosemary, rose, and geranium scents. Further, systolic blood pressure significantly decreased after introduction of all 10 types of aromatic oils, which indicates stress reduction. Thus, olfactory stimulation with aroma oil had a stabilizing effect on the prefrontal cortex and brain activity and decreased systolic blood pressure.
... In particular, alpha activity (7.5-12.5 Hz) is the dominant component of amplitude during relaxed and eyesclosed wakefulness [22]. While theta (4-7 Hz) frequencies are usually prominent during drowsiness [23], theta band activities orchestrate memory reactivation during wakefulness and sleep, and play an essential role in memory consolidation [24,25]. ...
... Regarding the alpha component, an increasing alpha component is considered a metric of relaxation and coziness, and the neural origin is derived from the occipital lobe [23,34,35]. Previous studies have reported that when people felt relaxed, calm, cozy, or were in a low-stress condition, their alpha amplitude of EEG increased [23,34,35]. ...
... Regarding the alpha component, an increasing alpha component is considered a metric of relaxation and coziness, and the neural origin is derived from the occipital lobe [23,34,35]. Previous studies have reported that when people felt relaxed, calm, cozy, or were in a low-stress condition, their alpha amplitude of EEG increased [23,34,35]. A study found that increase in the alpha and theta powers at the occipital lobes were associated with reduced attention-related arousal [36]. ...
This study compared the participants’ physiological responses and subjective evaluations of air scented with different concentrations of common rush (Juncus effusus L. var. decipiens Buchen.) (30 g and 15 g, with fresh air as a control). We asked 20 participants to complete a series of visual discrimination tasks while inhaling two different air samples. We evaluated (1) brain activity, (2) autonomic nervous activity, and (3) blood pressure and pulse rate, (4) in combination with self-evaluation. In addition, we quantified the concentrations of volatile organic compounds. The participants reported the scent to be sour, pungent, and smelly; this impression was likely caused by hexanal and acetic acid. Although the self-evaluations showed that participants did not enjoy the scent, their alpha amplitudes of electroencephalogram and parasympathetic nervous activity were increased, suggesting that participants were relaxed in this atmosphere. Moreover, a lower concentration resulted in a greater induction of relaxation. While the air was not pleasant-smelling, the volatile organic compounds present had a positive psychophysiological impact.
... Electroencephalography (EEG) is one of the most popular methods for observing brain oscillations due to its cost efficiency. Brain waves are classified by frequencies ranging from 0.05 to 500 Hz such as delta wave (0-4 Hz), theta wave (4)(5)(6)(7)(8), alpha wave (8)(9)(10)(11)(12)(13), beta wave (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30), and gamma (above 30 Hz) [10]. In this study, we focused on tangerine (Citrus tangerina) peel essential oil. ...
... In the case of mid beta wave of 15-20 Hz with high significance in active thinking and high alertness, Kim M. has shown that mid beta wave was increased during inhalation of (+)-α-pinene and terpinolene, which is correlated to decreased mid beta, indicating relaxation and reducing stress [15,18]. In addition, the effect of essential oil of Inula helenium root decreases the mid beta but only in the parietal region [19]. Each region of the brain is responsible for different functions from homeostatic functions to higher functions. ...
... Data analysis for EEG: raw data were processed by power spectral analysis, and frequency domain data are characterized as slow alpha (8)(9)(10)(11), fast alpha (11)(12)(13), low beta (13-15 Hz), mid beta (15)(16)(17)(18)(19)(20), and high beta (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30). This describes the distribution of electrical activity across the brain regions and was produced to show overview activities using GraphPad Prism 8. ...
Tangerine (Citrus tangerina) is one of the most important crops of Thailand with a total harvest that exceeds 100,000 tons. Citrus essential oils are widely used as aromatherapy and medicinal agents. The effect of tangerine essential oil on human brain waves and sleep activity has not been reported. In the present study, we therefore evaluated these effects of tangerine essential oil by measurement of electroencephalography (EEG) activity with 32 channel platforms according to the international 10–20 system in 10 male and 10 female subjects. Then the sleep onset latency was studied to further confirm the effect on sleep activity. The results revealed that different concentrations, subthreshold to suprathreshold, of tangerine oil gave different brain responses. Undiluted tangerine oil inhalation reduced slow and fast alpha wave powers and elevated low and mid beta wave powers. The subthreshold and threshold dilution showed the opposite effect to the brain compared with suprathreshold concentration. Inhalation of threshold concentration showed effectively decreased alpha and beta wave powers and increased theta wave power, which emphasize its sedative effect. The reduction of sleep onset latency was confirmed with the implementation of the observed sedative effect of tangerine oil.
... The functional changes of the brain, provoked through exposure to fragrances, are highly connected with the alteration of neuronal electrical activity [8,9]. Previously, several studies have reported that electroencephalograph (EEG) techniques are commonly used for determining spontaneous brain wave alterations during the inhalation of fragrances [10][11][12][13]. In a recent study, the inhalation of Abies koreana essential oil, through both nostrils and uninostrils, exhibited significantly different EEG activities in different brain regions [14]. ...
... The Fast Fourier transform was used to measure the mean power values (µV 2 ) of each segment. The mean power spectrum values were estimated for 25 EEG indices such as AT, Absolute theta (4~8 Hz); AA, Absolute alpha (8~13 Hz); AB, Absolute beta (13~30 Hz); AG, absolute gamma (30~50 Hz); ASA, Absolute slow alpha (8~11 Hz); AFA, Absolute fast alpha (11~13 Hz); ALB, Absolute low beta (12~15 Hz); AMB, Absolute mid beta (15~20 Hz); AHB, Absolute high beta (20~30 Hz); RT, Relative theta (4~8 Hz)/(4~50 Hz); RA, Relative alpha (8~13 Hz)/(4~50 Hz); RB, Relative beta (13~30 Hz)/(4~50 Hz); RG, Relative gamma (30~50 Hz)/(4~50 Hz); RSA, Relative slow alpha (8~11 Hz)/(4~50 Hz); RFA, Relative fast alpha (11~13 Hz)/(4~50 Hz); RLB, Relative low beta (12~15 Hz)/(4~50 Hz); RMB, Relative mid beta (15~20 Hz)/(4~50 Hz); RHB, Relative high beta (20~30 Hz)/(4~50 Hz); RST, Ratio of SMR to theta (12~15 Hz)/(4~8 Hz); RMT, Ratio of mid beta to theta (15~20 Hz)/(4~8 Hz); RSMT, Ratio of SMR~mid beta to theta (12~20 Hz)/(4~8 Hz); RAHB, Ratio of alpha to high beta (8~13 Hz)/(20~30 Hz); SEF50, Spectral edge frequency 50% (4~50 Hz); SEF90, Spectral edge frequency 90% (4~50 Hz); ASEF, Spectral edge frequency 50% of alpha (8~13 Hz) [13]. Statistical analysis was performed with SPSS version 18 statistics for windows (SPSS, Inc., Chicago, IL, USA). ...
... Furthermore, a significant reduction of theta activity was noticed, due to the exposure of C10 via the left and right nostril inhalations. The reduction in theta wave activity is mainly linked to the formation of memory [13,27,28]. In the present study, the reduction of theta wave activity suggests that the binasal and uninasal inhalations of C10 may enhance memory formation. ...
Fragrances play a pivotal role in humans’ psychological and physiological functions through the olfactory system. Aldehydes are important organic compounds with a variety of fragrance notes. Particularly, nonanal (C9) and decanal (C10) aldehydes are important natural fragrant components used to enhance floral, as well as citrus notes in perfumery products. In general, each nostril of the human nose is tuned to smell certain odor molecules better than others due to slight turbinate swelling between the nostrils. Hence, the objective of the present investigation was aimed to evaluate the influence of binasal and uninasal inhalations of C9 and C10 aldehydes on human electroencephalographic (EEG) activity. Twenty healthy participants (10 males and 10 females) participated in this study. The EEG readings were recorded from 8 electrodes (QEEG-8 system) according to the International 10-20 System. The results revealed that C10 exposure exhibited significantly different EEG changes, during binasal and uninasal inhalations. In different brain regions, C10 odor markedly decreased the absolute alpha and absolute beta power spectra. In regards to C9 odor, significant changes of EEG power spectra were noticed only during binasal inhalation. In addition, C10 mainly produced changes at the left parietal site (P3) than other brain sites. In conclusion, the variations in EEG activities of C9 and C10 aldehydes might be owing to their characteristic fragrance quality, as well as the influence of nostril differences.
... Elecampane (Inula helenium L.) is a perennial herbaceous plant of the Asteraceae family, which grows as a wild and common garden plant throughout the world (Spiridon et al. 2011;Sowndhararajan et al. 2016). The elecampane rhizome (ER) is known to contain high amounts of eudesmane-type sesquiterpene lactones (e.g. ...
... alantolactone and isoalantolactone), triterpenes, thymol derivatives, phenolic acids, flavonoids and inulin (Bourrel et al. 1993;Petkova et al. 2015). Besides using as a flavour additive, ER has been used in the traditional and folk medicine of different countries against a variety of ailments, including asthma, bronchitis, whooping cough, tuberculosis, gastritis, enterocolitis and digestive disorders (Stojanović-Radić et al. 2012;Sowndhararajan et al. 2016). Today, ER preparations are used mostly to quiet coughing, stimulate digestion and soothe the stomach (Richters 2015). ...
... Also, inclusion levels of HEER increased the digestibility of crude protein that reached significant level versus the control in HEER 1000 group. These findings are accorded well with the traditional usage of ER as a stimulant of digestive systems (Sowndhararajan et al. 2016). Our results are also consistent with those of previously published reports (Wang et al. 2008;Dieumou et al. 2011), which found that supplementation with herbal extracts improved nutrient digestibility and BW of the broiler chickens as compared to the unsupplemented birds. ...
In this study, the effects of dietary methanol and n-hexane extracts of elecampane rhizome (MEER and HEER, respectively) on growth performance, apparent ileal nutrient digestibility (AID), ileal microbiota, intestinal morphology and antioxidant status of the intestinal mucosa were compared in broiler chickens. In total, 450 1-d-old male chicks were allotted into five groups in six replicates of 15 chicks each. Dietary treatments included: a control, control plus 500 or 1000 mg MEER per kg diet (MEER500 and MEER1000) and control plus 500 or 1000 mg HEER per kg diet (HEER500 and HEER1000). Broiler performance was not affected by dietary treatments during the starter and grower periods. However, in the finisher (25–42 d) and entire (1–42 d) periods, an increase in body weight gain and a corresponding decrease in feed conversion ratio was noticed when birds received Diets MEER1000 or HEER1000. Also, considering the entire trial, the growth-promoting action of MEER was found to be greater than HEER. When compared with the control, AID of dry matter, organic matter, ether extract (EE) and gross energy (GE) were increased by all treatments, while the AID of EE and GE were also improved by increased extract level. Additionally, HEER groups had significantly increased AID of crude protein. The counts of Escherichia coli and Clostridium spp. were suppressed while the number of Lactobacillus spp. increased in response to an elevated extract level. Meanwhile, the ileum of MEER groups contained lower numbers of Clostridium spp. and greater numbers of Lactobacillus spp. when compared with HEER groups. The duodenal and jejunal structures were not associated with dietary treatments. However, a decreased ileal crypt depth and an increased villus to crypt ratio were observed with addition of extracts, which was more intense with MEER. A lower malondialdehyde content and a higher activity of superoxide dismutase, catalase and glutathione peroxidase were detected in duodenal and jejunal mucosa with increased extract level, and in jejunum, the antioxidant capability of MEER was found to be stronger than HEER. The antioxidant properties of the ileal mucosa were also improved in response to MEER, which was not observed after HEER inclusion. Overall, MEER seems to be a better choice of treatment owing to its more effective benefits on broiler performance, ileal microbiota, gut morphology and antioxidant ability of the intestinal mucosa.
... The EEG is a widely used neurophysiological evaluation technique to reflect the function of human brain. According to the frequency range, the EEG waves are categorized into five major EEG rhythms such as delta waves (0-4 Hz), theta waves (4-8 Hz), alpha waves (8-13 Hz), beta waves (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30), and gamma waves . Many EEG studies have demonstrated significant alterations in the EEG spectrum values during the inhalation of aroma [5]. ...
... In addition, absolute beta, absolute mid beta, and relative theta activities decreased during the inhalation of essential oil. These changes in the EEG activities may enhance the alertness state of the brain [28]. In another study, the relative high beta activity significantly increased in the right temporal region during the inhalation of (+)-limonene. ...
... During performance of difficult task, the theta wave has been believed to maintain attention. In addition, reduction in theta wave activity is mainly related to the formation of memory [28,32,33]. In the present study, the reduction of theta wave activity suggests that the uninasal (right) inhalation of AEO may enhance the alertness and attention state of the brain function. ...
Objectives . The present work investigates the effect of essential oil from the twigs of Abies koreana on electroencephalographic (EEG) activity of human brain in order to understand the influence of binasal and uninasal inhalations. Methods . To accomplish this study, the essential oil from the twigs of A. koreana (AEO) was isolated by steam distillation and the EEG readings were recorded using QEEG-8 system from 8 grounding electrodes according to the International 10-20 System. Results . D-Limonene (25.29%), bornyl acetate (19.31%), camphene (12.48%), α -pinene (11.88%), β -pinene (6.45%), and eudesm-7(11)-en-ol (5.38%) were the major components in the essential oil. In the EEG study, the absolute alpha (left frontal and right parietal) and absolute fast alpha (right parietal) values significantly increased during the binasal inhalation of AEO. In the uninasal inhalation, absolute beta and theta values decreased significantly, especially in the right frontal and left and right parietal regions. The results revealed that the AEO produced different EEG power spectrum changes according to the nostril difference. Conclusion . The changes in EEG values due to the inhalation of AEO may contribute to the enhancement of relaxation (binasal inhalation) and alertness/attention (right uninasal inhalation) states of brain which could be used in aromatherapy treatments.
... The administration methods of fragrances to study the EEG activity were varied among the authors. In general, the fragrance administration has been carried out by a known volume of fragrance (diluted or undiluted), was dropped on the filter paper or perfume's test strip and then placed about 3-10 cm in front of the subject's nose [16,59,60]. Fragrances were also presented to the subject by a funnel-shaped supplier fixed on the chest (15 cm under the nose) with a flow rate of 2000 mL oil/min [61]. ...
... The set of 31 electrodes were also used for the EEG study [12,16]. The electrodes included eight channels (Fp1, Fp2, F3, F4, T3, T4, P3 and P4), and a grounding electrode to the left earlobe, and a standard electrode to the right earlobe were frequently used in the EEG study [60,64]. ...
... The source of the map in the food condition seemed to be associated with the processing of rewards, whereas the specific map in the non-food condition reflects odor characteristics excluding the reward. Sowndhararajan et al. [60] investigated the effect of essential oil inhalation of Inula helenium root on human EEG activity. The absolute theta (all the regions except T3), beta (Fp1) and mid beta (P4) and relative theta (Fp1, Fp2, F3 and F4) wave activities significantly decreased during the essential oil inhalation compared to before inhalation. ...
The influence of fragrances such as perfumes and room fresheners on the psychophysiological activities of humans has been known for a long time, and its significance is gradually increasing in the medicinal and cosmetic industries. A fragrance consists of volatile chemicals with a molecular weight of less than 300 Da that humans perceive through the olfactory system. In humans, about 300 active olfactory receptor genes are devoted to detecting thousands of different fragrance molecules through a large family of olfactory receptors of a diverse protein sequence. The sense of smell plays an important role in the physiological effects of mood, stress, and working capacity. Electrophysiological studies have revealed that various fragrances affected spontaneous brain activities and cognitive functions, which are measured by an electroencephalograph (EEG). The EEG is a good temporal measure of responses in the central nervous system and it provides information about the physiological state of the brain both in health and disease. The EEG power spectrum is classified into different frequency bands such as delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), beta (13–30 Hz) and gamma (30–50 Hz), and each band is correlated with different features of brain states. A quantitative EEG uses computer software to provide the topographic mapping of the brain activity in frontal, temporal, parietal and occipital brain regions. It is well known that decreases of alpha and beta activities and increases of delta and theta activities are associated with brain pathology and general cognitive decline. In the last few decades, many scientific studies were conducted to investigate the effect of inhalation of aroma on human brain functions. The studies have suggested a significant role for olfactory stimulation in the alteration of cognition, mood, and social behavior. This review aims to evaluate the available literature regarding the influence of fragrances on the psychophysiological activities of humans with special reference to EEG changes.
... Inula helenium roots mainly comprise the polysaccharide inulin (up to 44%) [13], aside sesquiterpene lactones, thymol derivates, phenolic acids, and flavonoids [174]. Elecampane EO (1-5% in the roots) is described as woody, balsamic, and earthy in its odor [175], being solid at room temperature. It contains a mixture of white crystals of sesquiterpenoid lactones and a liquid yellow phase attributed to alantol [176]. ...
... Although further studies are necessary, it seems that brain function becomes highly affected by increasing alertness and concentration. Therefore, elecampane oil inhalation may have the potential to treat psychophysiological disorders [175]. ...
Since ancient times, plant roots have been widely used in traditional medicine for treating various ailments and diseases due to their beneficial effects. A large number of studies have demonstrated that—besides their aromatic properties—their biological activity can often be attributed to volatile constituents. This review provides a comprehensive overview of investigations into the chemical composition of essential oils and volatile components obtained from selected aromatic roots, including Angelica archangelica, Armoracia rusticana, Carlina sp., Chrysopogon zizanioides, Coleus forskohlii, Inula helenium, Sassafras albidum, Saussurea costus, and Valeriana officinalis. Additionally, their most important associated biological impacts are reported, such as anticarcinogenic, antimicrobial, antioxidant, pesticidal, and other miscellaneous properties. Various literature and electronic databases—including PubMed, ScienceDirect, Springer, Scopus, Google Scholar, and Wiley—were screened and data was obtained accordingly. The results indicate the promising properties of root-essential oils and their potential as a source for natural biologically active products for flavor, pharmaceutical, agricultural, and fragrance industries. However, more research is required to further establish the mechanism of action mediating these bioactivities as well as essential oil standardization because the chemical composition often strongly varies depending on external factors.
... The rhizome of elecampane contains large levels of eudesmane-type sesquiterpene lactones (e.g., alantolactone and isoalantolactone), phenolic acids, flavonoids, and inulin (Petkova et al. 2015). Pharmacological research has also indicated that the elecampane rhizome extracts possess various physiological functions, including antibacterial, antioxidant, anti-cancer, and anti-inflammatory (Jiang et al. 2016), which have been widely used against various inflammatory diseases (Sowndhararajan et al. 2016). Therefore, considering the pharmaceutical (antioxidant and anti-inflammatory) features of elecampane rhizome reported in vitro and in vivo, and the scarcity of data the regarding the protective effects of elecampane rhizome extract (ERE) against oxidative stress damage induced by MTX, the present study examined the effects of ERE on serum lipid profile, hepatic and renal toxicity marker concentrations, and histopathological changes in liver and renal tissue during MTX induced experimental toxicity. ...
Methotrexate (MTX) is a chemotherapy drug used to treat cancer and inflammatory diseases; however, its clinical applicability is limited due to its cytotoxic nature. The present study tested elecampane (Inula helenium L.) rhizome extract (ERE) for its protective effects against MTX-induced hepatotoxicity and nephrotoxicity in male rats. The rats were divided into five experimental groups (n = 10): control (physiological saline); MTX, physiological saline, and MTX [40 mg/kg intraperitoneal (i.p.)] on the fourth day; and three groups in which rats concurrently received MTX plus three doses of ERE (100, 200, 400 mg/kg) orally for 10 consecutive days. The findings revealed that MTX administration substantially elevated serum concentrations of total cholesterol (TC), low-density lipoproteins cholesterol (LDL-C), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), blood urea nitrogen, and creatinine. Additionally, it increased malondialdehyde (MDA), interleukin-1β (IL-1β), and tumor necrotic factor-α (TNFα) levels in the liver and renal tissues while decreasing superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities. However, treatment with ERE at a dosage of 400 mg/kg reversed the adverse effects of MTX toxicity by decreasing the levels of TC, LDL-C, MDA, AST, ALT, ALP, IL-1β, TNFα and increasing the activities of GPx, CAT, and SOD in the tissues mentioned above. A histological examination of the liver and renal tissues also confirmed the ameliorating effects of ERE. The present study indicated that EER could inhibit MTX-induced hepatotoxicity and nephrotoxicity by improving antioxidant defense and decreasing oxidative stress and inflammation.
... We did not find any studies on the time course of the effects of essential oil inhalation on brain activity related to working memory functions. This study examined temporal changes through four epochs spanning a 2-min period of essential oil inhalation, with 30 s (Sowndhararajan et al., 2015(Sowndhararajan et al., , 2016 as one epoch. ...
Introduction
Essential oil inhalation has various effects on the human body. However, its effects on cognitive function and the neural basis remain unclear. We aimed to investigate the effects of inhaling lemon, sandalwood, and kusunoki essential oils on human brain activity and memory function using multichannel electroencephalography and brain source activity estimation.
Methods
Participants performed a letter 2‐back working memory task during electroencephalography measurements before and after essential oil inhalation. Brain activation, task difficulty, concentration degree, and task performance were compared among the essential oils and a fragrance‐free control.
Results
Task performance significantly improved after lemon essential oil inhalation. Lemon essential oil inhalation resulted in delta and theta band activation in the prefrontal cortex, including the anterior cingulate gyrus and orbitofrontal cortex, superior temporal gyrus, parahippocampal gyrus, and insula. During inhalation, persistent alpha band activation was observed in the prefrontal cortex, including the anterior cingulate gyrus. Sandalwood essential oil inhalation led to beta and gamma band activation in the prefrontal cortex, including the anterior cingulate gyrus.
Conclusion
Our findings demonstrate that different essential oils have specific effects on brain activity related to emotion and memory processing.
... In general, the beta wave activity decreases during the drowsiness state and increases with a high alertness level [40]. Many studies have demonstrated that essential oils affect the EEG spectrum power in rats and humans. ...
Background:
Aromatherapy has been proved to be effective in alleviating anxiety in practices and research. Recently, copaiba oil (CPO) is popular in the market and is recommended for anxiety relief in aromatherapy practice. However, relevant scientific research is still lacking.
Methods:
A randomized controlled trial was designed to evaluate the anxiety-relieving effect of CPO inhalation in 22 adults. Jojoba oil was used as the control treatment. N-back and mental arithmetic tasks were used as stress stimulation. CPO or control intervention was carried out after the n-back training phase. The State-Trait Anxiety Inventory (STAI), EEG activities, physiological indexes including heart rate (HR), blood pressure (BP), blood oxygen saturation, and salivary cortisol were assessed in different phases of the experimental process.
Results:
There was no significant difference in the change of HR and BP between the CPO and control groups before odor intervention. The S-AI scores of the CPO treated participants decreased after the n-back and mental arithmetic tests and were significantly lower than those of the participants who received control treatments. The HR and salivary cortisol of participants who received CPO intervention significantly decreased during the n-back and mental arithmetic tests. Furthermore, a remarkable decrease of beta wave activity was observed in the left midfrontal region (F3) when the participant received the CPO intervention.
Conclusion:
The study's findings supported that the CPO odor showed beneficial effects on alleviating anxiety based on several indicators in subjective, physiological, and EEG measurements.
... The components of the oil were identified by comparison of their mass spectra fragmentation and computer matching using the Wiley 7n libraries (Database/ChemStation data system). The experimental protocol was adapted from Sowndhararajan et al. [33]. The subjects were asked to sit quietly in a recliner to limit movement of their head. ...
The functional food market is growing with a compound annual growth rate of 7.9%. Thai food recipes use several kinds of herbs. Lemongrass, garlic, and turmeric are ingredients used in Thai curry paste. Essential oils released in the preparation step create the flavor and fragrance of the famous tom yum and massaman dishes. While the biological activities of these ingredients have been investigated, including the antioxidant, anti-inflammatory, and antimicrobial activities, there is still a lack of understanding regarding the responses to the essential oils of these plants. To investigate the effects of essential oil inhalation on the brain and mood responses, electroencephalography was carried out during the non-task resting state, and self-assessment of the mood state was performed. The essential oils were prepared in several dilutions in the range of the supra-threshold level. The results show that Litsea cubeba oil inhalation showed a sedative effect, observed from alpha and beta wave power reductions. The frontal and temporal regions of the brain were involved in the wave alterations. Garlic oil increased the alpha wave power at lower concentrations; however, a sedative effect was also observed at higher concentrations. Lower dilution oil induced changes in the fast alpha activity in the frontal region. The alpha and beta wave powers were decreased with higher dilution oils, particularly in the temporal, parietal, and occipital regions. Both Litsea cubeba and turmeric oils resulted in better positive moods than garlic oil. Garlic oil caused more negative moods than the others. The psychophysiological activities and the related brain functions require further investigation. The knowledge obtained from this study may be used to design functional food products.
... Elecampane (Inula helenium L.) is a perennial plant that grows abundantly throughout the world (Spiridon et al., 2011;Sowndhararajan et al., 2016). Besides using as a flavor additive, the elecampane rhizome (ER) is used in the folk medicine as a treatment for a diversity of respiratory disorders such as bronchitis, asthma, whooping cough, and hypoxic lung diseases (Huo et al., 2010;Shoja et al., 2015). ...
This study was designed to assess the preventive effect of an ethanol extract of elecampane (Inula helenium L.) rhizome (EEER) on ascites in broiler chickens. A total of 900 1-day-old male chicks (Ross 308) were assigned to five treatment groups, each of which had six pens of 30 chicks per pen. The control birds were housed in a thermoneutral chamber and fed a basal diet, while the other four groups were reared in a cold chamber to induce ascites and fed the basal diet supplemented with either 0, 500, 1000, or 2000 mg/kg of EEER. Associated with cold treatment, there were decreases in feed intake, body weight, and body weight gain and an increase in ascites mortality (P < 0.05), which coincided with increased hematological values (erythrocytes count, hemoglobin, and hematocrit) and induction of right ventricle hypertrophy at 24 and 42 days of age (P < 0.05). These adverse effects of the cold ambient condition could be linearly decreased by increasing the EEER content in the diet (P < 0.05), but they did not normalize to the control levels (P < 0.05). Also, at both 24 and 42 days of age, the cold-treated birds revealed an increase in malondialdehyde (MDA) contents in plasma and tissues (heart, liver, and lungs) that accompanied with a noticeable decline in superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities and an increase in plasma aspartate aminotransferase (AST) and alanine aminotrans-ferase (ALT) activities (P < 0.05). These changes paralleled a decrease in plasma nitric oxide (NO) levels (P < 0.05). Treatment with graded increments of EEER showed a linear decrease in MDA levels and linearly increased SOD and GPx activities (P < 0.05). However, it failed to restore the oxidative status of the heart and lungs towards close the control levels (P < 0.05), and this was also the case for ALT and AST activities and NO levels. In conclusion, EEER appears to be a useful dietary agent for attenuating the progression of cold-induced ascites in broiler chickens.
... The protocol was adapted from Sowndhararajan et al. [18]. The subjects sat quietly in a recliner. ...
Essential oils are volatile fragrance liquids extracted from plants, and their compound annual growth rate is expected to expand to 8.6% from 2019 to 2025, according to Grand View Research. Essential oils have several domains of application, such as in the food and beverage industry, in cosmetics, as well as for medicinal use. In this study, Michelia alba essential oil was extracted from leaves and was rich in linalool components as found in lavender and jasmine oil. The effects of inhaling michelia oil on human brainwaves still need to be elucidated. Ten male and ten female subjects were recruited. Thirty-two-channel electroencephalography was recorded. The raw data were spectrally analyzed for slow alpha, fast alpha, low beta, mid beta, and high beta activities. The results demonstrate that michelia leaf oil could reduce the alertness level observed by beta wave decrease and fast alpha wave activity increase. The inhalation of pure linalool showed virtually identical responses as the michelia oil inhalation. In conclusion, the sedative effects of michelia oil inhalation might originate from its major linalool component.
... Advocates of EOs will point to the ostensible benefits they provide through their antioxidant, antibacterial, antifungal, antimicrobial, and antiplaque/antigingivitic properties, as well as their performance as an effective insect repellant [4][5][6][7][8][9][10]. In our review of the literature on EOs, many of these studies compare the effectiveness of EOs to existing treatments, placebos, no treatment, or in combination with existing treatments on varying outcome variables [e.g., hormone levels, brain activation, subjective evaluations of stress, chemical reactions with other substances; [11][12][13][14][15][16][17][18][19][20][21]. The purported benefits of EOs range from treating pain [in combination with conventional treatments ; 22], to memory and mood enhancement [e.g., promoting a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 calmness, alertness, contentment; 23,24], to insomnia relief [25,26]. ...
Essential oil (EO) use is growing in popularity and ostensibly used for treating or preventing various ailments or conditions. Despite the increase in use, there is a paucity of research on psychosocial predictors of EO use and their perceived effectiveness. However, several psychosocial characteristics are associated with health-promoting behavior and a tendency to believe in homeopathic cures. In the current study, we examined a variety of individual differences in the use and perceived effectiveness of essential oils in a sample of 1,202 participants (Mage = 31.33, SD = 13.77; 61.7% women, 75.6% Caucasian). We found that receptivity to pseudo-profound fabricated statements and religiosity were the most consistent predictors of greater use of, perceived effectiveness of, and a willingness to spend more money on EOs.
... Elecampane (Inula helenium L.), taxonomically belongs to Asteraceae family, is a perennial herb widely distributed in Asia, Africa, Europe, and Northern America (Sowndhararajan et al., 2016;Spiridon et al., 2011). The rhizome of this plant is known to contain high amounts of eudesmanolide-type sesquiterpene lactones (e.g., alantolactone and isoalantolactone), triterpenes, thymol derivatives, phenolic acids, flavonoids, elecampane and inulin (Bourrel et al., 1993;Petkova et al., 2015). ...
This study tested the efficacy of ethanol extract of elecampane (Inula helenium L.) rhizome (EEER) upon growth performance and physiological characteristics of broiler chickens. A total of 360 one-day-old male broiler chickens were randomly allocated to 4 treatments with 6 replicates and 15 chickens per replicate. Treatments consisted of different EEER concentrations (0, 250, 500, or 1000 mg/kg) included in a diet of 3-phase feeding program (starter, grower, and finisher) during the periods of 1–10, 11–24 and 25–42 days of age, respectively. Feed intake was not affected by dietary treatments throughout the study. However, considering the grower and finisher periods or the whole experiment, there were linear improvements in body weight gain and feed conversion ratio with increasing inclusion rate of EEER (P < 0.05). Increasing dosages of EEER produced linear increases in digestibility of dry matter, organic matter, ether extract, and gross energy (P < 0.05). Apparent digestibility of crude protein was not different among diets. A decrease in the count of Escherichia coli (P < 0.05; quadratic) and Clostridium spp. (P < 0.05; linear) along with an increase in the count of Lactobacillus spp. (P < 0.05; linear and quadratic) was also observed with dietary EEER. Diet supplementation with EEER showed positive effects on intestinal mucosa development and intestinal antioxidant capacity. In ileum, there were linear increases in villus height and villus/crypt ratio and linear decreases in crypt depth and total mucosa thickness with increasing addition of EEER (P < 0.05). A linear increase in villus height and a parallel increase in villus/crypt ratio was also evident in the jejunum (P < 0.05). However, crypt depth and total mucosa thickness of the jejunum were not influenced by dietary treatments. In both the jejunal and ileal mucosa, dietary EEER induced a dose-related increase in the activities of superoxide dismutase, catalase, and glutathione peroxidase (P < 0.05), which was accompanied by a linear decrease in the content of malondialdehyde (P < 0.05). In conclusion, EEER can be considered as a suitable feed additive, which can have positive effects on growth performance, intestinal flora, and gastrointestinal health in broiler chickens.
... A literature survey revealed that Inula plants are rich source of biologically active compounds, mainly sesquiterpene lactones, flavonoids, and triterpenoids (Seca et al., 2014;. Surprisingly, the information on essential oil composition of Inula species is scarce and only few biological activities have been reported -antibacterial (Deriu et al., 2008;Priydarshi et al., 2016), antifungal (Chauhan and Saxena, 1985;Haoui et al., 2016), and influence of I. helenium essential oil on electroencephalographic activity of the human brain (Sowndhararajan et al., 2016). Inula aschersoniana Janka is a species with areas of distribution in Bulgaria, Greece, Macedonia, and Turkey (The Global Species, 2009). ...
... The mean power values [microvolt square (mV 2 )] were calculated for 25 EEG analysis indicators including absolute and relative power spectra of theta, alpha, beta and gamma waves[13]. The t-mapping of EEG power spectra was constructed by Telescan software package (LXSMD61, LAXTHA Inc., Daejeon, Republic of Korea). ...
Objectives
The present study aimed to investigate the effect of inhalation of essential oil (EO) and supercritical carbon dioxide extract (SC-CO2) from the root of A. gigas on human electroencephalographic (EEG) activity.
Materials and methods
For this purpose, the EO was obtained from the root of A. gigas by steam distillation and SC-CO2 was obtained at 50 °C and 400 bar for 1 h. The EEG readings were recorded using the QEEG-8 system from 8 electrode sites according to the International 10-20 system.
Results
In the EEG study, the absolute low beta (left temporal and left parietal) activity significantly increased during the inhalation of EO. In the case of SC-CO2 inhalation, there was no significant change in absolute waves.
Conclusion
The results revealed that the EO of A. gigas root produced significant changes in the absolute low beta activity and these changes may enhance the language learning abilities of human brain.
The objective of this work was to study the effect of carnauba wax containing orange oil on physical qualities (weight loss, color, and firmness) and sensory perception after consumption. First, the appropriate essential oil for use with salacca fruit was investigated. Then, the best pairing of carnauba wax and orange oil was employed to study salacca preservation. Carnauba wax (2.5%) containing orange oil at a concentration of 0.04-0.16% was coated on salacca and examined for weight loss, color and firmness after storage for 9 d. Sensory perception in terms of sensory acceptance, rejection threshold and prevalent attributes related to aroma profiles was evaluated. The human brain response during salacca consumption was examined by electroencephalography (EEG). The results illustrated that salacca treated with carnauba wax containing orange oil at a concentration of 0.08% could maintain the desired qualities and provide moderate organoleptic approval of salacca. In addition, EEG demonstrated that consumption of orange oil-treated salacca could increase the alertness state of brain function in the human response. This finding can be used to apply orange oil to salacca fruit to enhance flavor, which was shown to achieve better consumer approval based on human brain activity.
Volatile organic compounds are widely used to manufacture various products in addition to research purposes. They play an important role in the air quality of outdoor and indoor with a pleasant or unpleasant odor. It is well known that the odor of chemicals with different structures can affect brain functions differently. In general, organic compounds are mainly characterized by their functional groups. Acetic acid, acetaldehyde, acetone, and acetonitrile are widely used laboratory chemicals with the same methyl group, but different functional groups. Hence, the present study was aimed to investigate whether the exposure of these four chemicals (10%) exhibits the same electroencephalographic (EEG) activity or different. For this purpose, the EEG was recorded in 20 male healthy volunteers. The EEG was recorded from 32 electrodes located on the scalp, based on the International 10-20 system with modified combinatorial nomenclature. The results indicated that tested subjects are less sensitive to acetic acid odor than other three chemicals. The absolute theta activity significantly increased at Cp5 and F8 regions, and the relative mid-beta (RMB) significantly decreased at Fc1 region during the exposure of acetic acid. On the other hand, acetaldehyde, acetone, and acetonitrile produced EEG changes in many indices such as relative theta, relative gamma, relative high beta, relative beta, relative slow beta, the ratio of alpha to high beta, and spectral edge frequencies. However, there was no significant change in the absolute wave activity. Although acetaldehyde, acetone, and acetonitrile odors affected almost similar EEG indices, they exhibited changes in different brain regions. The variations in the EEG activity of these chemicals may be due to the activation of different olfactory receptors, odor characteristics, and structural arrangements.
Isoalantolactone is one of the major active ingredients from Inula helenium L. However, it is low cost-effective to isolate isoalantolactone from Inula helenium L. In this study, we optimized the extraction strategy and obtained a mixture of active ingredients with exact proportion (termed as F35), which were alloalantolactone, alantolactone and isoalantolactone at the ratio of 1/5/4 respectively. The anti-tumor activity of F35 was compared with isoalantolactone on pancreatic cancer cells. As a result, F35 showed nearly the same anti-proliferation activity as isoalantolactone in two cell lines. Both F35 and isoalantolactone could induce mitochondrion-related apoptosis at the concentration of 6 μg/ml. In addition, F35 inhibited colony-formation and migration of PANC-1 and SW1990 cells. To conclude, F35 exhibited similar anti-proliferation and anti-migration effect as isoalantolactone on two pancreatic cancer cell lines, suggesting that alantolactone or alloalantolactone might have comparable anti-tumor effect as isoalantolactone.
Introduction
Decanal (C10) is an important aldehyde, extensively used to enhance floral and citrus notes in various perfumery products. It is well-known that the human electroencephalographic (EEG) activity is highly susceptible to change due to the exposure of fragrances. However, the EEG findings exhibit non-stationary behavior in terms of analysis and recording time. Hence, the present study aimed to investigate the effect of inhalation of aldehyde C10 on the human EEG activity with respect to time series analysis.
Methods
Twenty healthy volunteers (10 men and 10 women) participated in the EEG study. The EEG data were recorded from 8 channels according to the International 10–20 System. The EEG readings were analyzed for every second by splitting the total 30 s data during the no odor and C10 odor exposures.
Results
The exposure of C10 odor produced significant changes (p < 0.05) in all the absolute waves at a certain time during the time series analysis. The results revealed that all absolute waves significantly decreased during the first 13 s period of time due to the exposure of C10 odor. After that, absolute alpha, absolute slow alpha, and absolute fast alpha markedly increased. Furthermore, the exposure to C10 appears to mainly affect the frontal regions, especially the left frontal region (F3) compared with other regions.
Conclusion
Our data suggest that the EEG activity of C10 odor is highly unstable in the time series analysis, thereby analysis time could play a key role in the EEG response to olfactory stimulation.
Driving drowsiness is a major cause of traffic accidents worldwide and has drawn the attention of researchers in recent decades. This paper presents an application for in-vehicle non-intrusive mobile-device-based automatic detection of driver sleep-onset in real time. The proposed application classifies the driving mental fatigue condition by analyzing the electroencephalogram (EEG) and respiration signals of a driver in the time and frequency domains. Our concept is heavily reliant on mobile technology, particularly remote physiological monitoring using Bluetooth. Respiratory events are gathered, and eight-channel EEG readings are captured from the frontal, central, and parietal (Fpz-Cz, Pz-Oz) regions. EEGs are preprocessed with a Butterworth bandpass filter, and features are subsequently extracted from the filtered EEG signals by employing the wavelet-packet-transform (WPT) method to categorize the signals into four frequency bands: α, β, θ, and δ. A mutual information (MI) technique selects the most descriptive features for further classification. The reduction in the number of prominent features improves the sleep-onset classification speed in the support vector machine (SVM) and results in a high sleep-onset recognition rate. Test results reveal that the combined use of the EEG and respiration signals results in 98.6% recognition accuracy. Our proposed application explores the possibility of processing long-term multi-channel signals.
Humans consume a wide range of foods, drugs, and dietary supplements that are derived from plants and which modify the functioning of the central nervous sytem (CNS). The psychoactive properties of these substances are attributable to the presence of plant secondary metabolites, chemicals that are not required for the immediate survival of the plant but which are synthesized to increase the fitness of the plant to survive by allowing it to interact with its environment, including pathogens and herbivorous and symbiotic insects. In many cases, the effects of these phytochemicals on the human CNS might be linked either to their ecological roles in the life of the plant or to molecular and biochemical similarities in the biology of plants and higher animals. This review assesses the current evidence for the efficacy of a range of readily available plant-based extracts and chemicals that may improve brain function and which have attracted sufficient research in this regard to reach a conclusion as to their potential effectiveness as nootropics. Many of these candidate phytochemicals/extracts can be grouped by the chemical nature of their potentially active secondary metabolite constituents into alkaloids (caffeine, nicotine), terpenes (ginkgo, ginseng, valerian, Melissa officinalis, sage), and phenolic compounds (curcumin, resveratrol, epigallocatechin-3-gallate, Hypericum perforatum, soy isoflavones). They are discussed in terms of how an increased understanding of the relationship between their ecological roles and CNS effects might further the field of natural, phytochemical drug discovery.
Using neurofeedback (NF), individuals can learn to modulate their own brain activity, in most cases electroencephalographic (EEG) rhythms. Although a large body of literature reports positive effects of NF training on behavior and cognitive functions, there are hardly any reports on how participants can successfully learn to gain control over their own brain activity. About one third of people fail to gain significant control over their brain signals even after repeated training sessions. The reasons for this failure are still largely unknown. In this context, we investigated the effects of spontaneous mental strategies on NF performance. Twenty healthy participants performed either a SMR (sensorimotor rhythm, 12–15 Hz) based or a Gamma (40–43 Hz) based NF training over ten sessions. After the first and the last training session, they were asked to write down which mental strategy they have used for self-regulating their EEG. After the first session, all participants reported the use of various types of mental strategies such as visual strategies, concentration, or relaxation. After the last NF training session, four participants of the SMR group reported to employ no specific strategy. These four participants showed linear improvements in NF performance over the ten training sessions. In contrast, participants still reporting the use of specific mental strategies in the last NF session showed no changes in SMR based NF performance over the ten sessions. This effect could not be observed in the Gamma group. The Gamma group showed no prominent changes in Gamma power over the NF training sessions, regardless of the mental strategies used. These results indicate that successful SMR based NF performance is associated with implicit learning mechanisms. Participants stating vivid reports on strategies to control their SMR probably overload cognitive resources, which might be counterproductive in terms of increasing SMR power.
The study was planned as a randomized, controlled, prospective study to determine the effect of aromatherapy on test anxiety. The sample of the study was composed of 50 students who constituted the study group and 45 students who were the controls. The study group was exposed to lavender inhalation. The mean anxiety score of the study group (42.76 ± 12.48) was lower than that of the control group (51.51 ± 12.21), and the difference between the groups was statistically significant (p = .002). This study shows that aroma inhalation decreases examination anxiety.
The purpose of this study was to investigate the inhibitory/bactericidal activity and cell membrane effects of the hydrodistilled essential oil of Inula helenium L. roots against Staphylococcus aureus. Additionally, detailed chemical investigation was done in order to pinpoint the most active oil constituents and also the parts of these molecules responsible for their antimicrobial effect. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the broth microdilution method. The membrane-active nature of this oil was investigated by measuring the culture turbidity, leakage of phosphates, and 260-nm-absorbing material, together with lysis of the exposed cells. Finally, the effect of the oil on the cells was visualized using scanning electron microscopy (SEM). The chemical composition of the essential oil was analyzed using gas chromatography-mass spectrometry (GC-MS) and preparative medium-pressure liquid chromatography (MPLC). Chemical modification of the oil was performed using catalytic hydrogenation (H(2), Pd/C) and reduction with NaBH(4). The MIC and MBC values were 0.01 μl mL(-1) and 0.02 μl mL(-1), respectively. Membrane damage was demonstrated through increased permeability (phosphates and nucleic acid leakage), followed by lysis of the exposed cells, captured on SEM images. The most active constituents were alantolactone, isoalantolactone, and diplophyllin. The essential oil showed very potent antistaphylococcal activity, with obvious membrane-damaging effects. Sesquiterpene lactones were found to be the most active principles of the oil, whose eudesmane core olefinic bonds, along with the α,β-methylene-lactone ring, are essential structural parts responsible for the exhibited antimicrobial activity.
To evaluate the effect of the odor of incense on brain activity, electroencephalograms (EEGs) and event-related potentials (ERPs) in a push/wait paradigm were recorded in 10 healthy adults (aged 23-39 years) with normal olfactory function. EEG was recorded from 21 electrodes on the scalp, according to the International 10-20 system, and EEG power spectra were calculated by fast Fourier transform for 3 min before and during odor presentation. ERPs were recorded from 15 electrodes on the scalp before, during and after exposure to incense with intervals of 10 min. In a push/wait paradigm, two Japanese words, 'push' as the go stimulus and 'wait' as the no-go stimulus, appeared randomly on a CRT screen with equal probability. The subjects were instructed to push a button whenever the 'push' signal appeared. Fast alpha activity (10-13 Hz) increased significantly in bilateral posterior regions during incense exposure compared to that during rose oil exposure. The peak amplitudes of no-go P3 at Fz and Cz were significantly greater during incense inhalation. The latencies of go P3 and no-go P3, and the amplitude and latencies of no-go N2 did not change by exposure to the odors of both incense, rose and odorless air. These results suggest that the odor of incense may enhance cortical activities and the function of inhibitory processing of motor response.
Essential oils have been used for thousands of years. Hippocrates claimed that the way to health was through aromatic baths and massages. Much anecdotal evidence exists regarding aromatherapy's positive effects on recipients. However, well-designed research trials are sparse. Certainly much controversy exists regarding the appropriate way to conduct research on holistic therapies. Can their effects be broken down and studied without contradicting the central premise on which holism is based? The purpose of this article is to review the current state of the science of aromatherapy and to propose future research. The author also offers guidelines for safe aromatherapy practice while awaiting future research on its clinical efficacy.
Aromatherapy is becoming increasingly popular; however there are few clear indications for its use. To systematically review the literature on aromatherapy in order to discover whether any clinical indication may be recommended for its use, computerised literature searches were performed to retrieve all randomised controlled trials of aromatherapy from the following databases: MEDLINE, EMBASE, British Nursing Index, CISCOM, and AMED. The methodological quality of the trials was assessed using the Jadad score. All trials were evaluated independently by both authors and data were extracted in a pre-defined, standardised fashion. Twelve trials were located: six of them had no independent replication; six related to the relaxing effects of aromatherapy combined with massage. These studies suggest that aromatherapy massage has a mild, transient anxiolytic effect. Based on a critical assessment of the six studies relating to relaxation, the effects of aromatherapy are probably not strong enough for it to be considered for the treatment of anxiety. The hypothesis that it is effective for any other indication is not supported by the findings of rigorous clinical trials.
The purpose of this study was to investigate EEG changes in subjects directly after inhalation of essential oils, and subsequently, to observe any effect on subjective evaluations. EEG and sensory evaluation were assessed in 13 healthy female subjects in four odor conditions. Four odor conditions (including lavender, chamomile, sandalwood and eugenol) were applied respectively for each subject in the experiment. The results were as follows. 1) Four basic factors were extracted from 22 adjective pairs by factor analysis of the sensory evaluation. The first factor was "comfortable feeling", the second "cheerful feeling", the third "natural feeling" and the fourth "feminine feeling". In the score of the first factor (comfortable feeling), the odors in order of high contribution are lavender, eugenol, chamomile and sandalwood. 2) Alpha 1 (8-10 Hz) of EEG at parietal and posterior temporal regions significantly decreased soon after the onset of inhalation of lavender oil (p < 0.01). Significant changes of alpha 1 were also observed after inhalation of eugenol or chamomile. The change after inhalation of sandalwood was not significant. These results showed that alpha 1 activity significantly decreased under odor conditions in which subjects felt comfortable, and showed no significant change under odor conditions in which subjects felt uncomfortable. These results suggest a possible correlation between alpha 1 activity and subjective evaluation.
The involvement of different oscillating neuronal systems during verbal creative thinking was investigated by multi-channel EEG measuring. The remote associates task (RAT) as a model of creative thinking in comparison to the resting condition and the simple associates task (SAT) was used. The EEG coherence along with spectral power density estimates were evaluated in each of the six frequency bands in 4-30 Hz range. We have found out RAT-related EEG changes mainly in the theta1, alpha1, alpha2 and beta2 bands. The RAT-induced cortical activation was differed from the SAT-induced EEG pattern by (i) widespread enhancement of power and coherence in the beta2, (ii) the theta1 power increase in the frontal cortex, and (iii) increased desynchronization of the alpha1,alpha2 mainly over posterior cortex together with the alpha1 coherence decrease in the prefrontal sites. Originality scores of the verbal associates positively correlated with an increase of coherence focused in the fronto-parietal regions of both hemispheres in the beta2 and in the left parieto-temporal loci in the alpha1. Additionally, more original responses positively correlated with amplitude of the alpha1 mostly in the left hemisphere. We propose that widespread cortical integration of multi-component internal processing has been simultaneously mediated during creative verbal thinking. The selectively distributed theta, alpha, and beta oscillations reflect intra- and inter-hemispheric communication networks with different functional relations to the RAT solving. The theta1 and alpha1 rhythms seem to specifically relate to top-down information processing such as deliberate sustained attention and working-memory-retention during defocused attention, respectively, whereas larger interregional synchrony in the beta2 band may mediate 'differential' attention to diffusely activating alternative meanings of words and remote associates from coarse semantic coding.
In this work we report results regarding the in vitro antimicrobial activity of Inula helenium L. dried root extracts obtained by stepwise supercritical fluid extraction (SFE) and by hydrodistillation (HD). Inula helenium L. (Compositae family) is a perennial plant widely occurring in Europe and East Asia. Its oil is one of the richest sources of sesquiterpenoid lactones, which have strong anthelminthic activity and have the potential to induce detoxifying enzymes. Inula helenium L. roots (C-040705130905) were purchased from Minardi (Bagnacavallo-Ravenna, Italy). Supercritical CO<sub>2</sub> extraction was performed in a laboratory apparatus equipped with a 400 cm3 extraction vessel operated in the single-pass mode of passing CO<sub>2</sub> through the fixed bed of charged vegetable particles. Extraction was carried out in a semibatch mode: batch charging of vegetable matter and continuous flow solvent. HD was performed for 4 h in a circulatory Clevenger-type apparatus up to exhaustion of the oil contained in the matrix, which was the same material as used in the SFE.
We reviewed studies from 2000 to 2008 on using essential oils for patients with depression or depressive symptoms and examined their clinical effects.
The review was conducted among five electronic databases to identify all peer-reviewed journal papers that tested the effects of aromatherapy in the form of therapeutic massage for patients with depressive symptoms.
The results were based on six studies examining the effects of aromatherapy on depressive symptoms in patients with depression and cancer. Some studies showed positive effects of this intervention among these three groups of patients.
We recommend that aromatherapy could continue to be used as a complementary and alternative therapy for patients with depression and secondary depressive symptoms arising from various types of chronic medical conditions. More controlled studies with sound methodology should be conducted in the future to ascertain its clinical effects and the underlying psychobiologic mechanisms.
The present studies sought to examine the effect of olfactory stimulation on human Central Nervous System activity. In the first experiment (n = 21), EEG response to the 'synthetic' odours of chocolate, spearmint, almond, strawberry, vegetable, garlic and onion, and cumin or no odour was recorded from 19 electrodes (F3, F4, F7, F8, Fz, T3, T4, T5, T6, P3, P4, Pz, O1, O2, C3, C4, Cz) in all EEG frequencies (delta, theta, alpha, beta1 and beta2). Exposure to the odour of chocolate was associated with significant reductions in theta activity when compared with the odours of almond and cumin, with a trend towards significance when compared with no-odour control. Exposure to the odour of spearmint was associated with a significant reduction in EEG theta when compared with the no-odour control. No significant effects were observed in other frequencies. In a second experiment (n = 15), EEG response to the odours of real foods (chocolate, baked beans, rotting pork) and two controls (no odour and hot water) was recorded as in Experiment 1. The odour of chocolate was associated with significantly less theta activity than was any other stimulus. It is hypothesised that the alterations in theta reflect shifts in attention or cognitive load during olfactory perception, with a reduction in theta indicating a reduced level of attention.
EEG activity, alertness, and mood were assessed in 40 adults given 3 minutes of aromatherapy using two aromas, lavender (considered a relaxing odor) or rosemary (considered a stimulating odor). Participants were also given simple math computations before and after the therapy. The lavender group showed increased beta power, suggesting increased drowsiness, they had less depressed mood (POMS) and reported feeling more relaxed and performed the math computations faster and more accurately following aromatherapy. The rosemary group, on the other hand, showed decreased frontal alpha and beta power, suggesting increased alertness. They also had lower state anxiety scores, reported feeling more relaxed and alert and they were only faster, not more accurate, at completing the math computations after the aromatherapy session.
To evaluate an aromatherapy service for older adults with physical health problems and their carers. The aromatherapy service was based in a carer support unit at a hospital in Birmingham. The research question was, 'What types of benefits do clients/carers report from aromatherapy?'
Qualitative analysis of interview scripts and written descriptions.
The interviews were carried out either at the carer support unit, at a connected day centre or at the client/carer's home.
The participants were six clients and four carers who were in contact with the carer support unit and had received aromatherapy from the aromatherapist in the past year.
The participants were interviewed using a semi-structured questionnaire to explore which part of a session they liked best, perceived benefits of aromatherapy and a smell attribution to certain essential oils. The aromatherapist was also asked to write descriptions of her perceived benefits for the clients and carers. The interviews were analysed qualitatively and compared to the aromatherapist's written descriptions.
All clients and carers said they benefited from the aromatherapy and felt more relaxed after a session. The qualitative analysis revealed a 70% area of overlap and a 30% 'hidden' area of congruence. The smell analysis revealed individual differences in attribution depending on past experience and expectation of oil presented.
The findings of this evaluation suggest the aromatherapy service offered was valuable to clients and carers and their perception of its benefits for them were largely congruent with those of the aromatherapist.
Two series of cytotoxic (IC50, K562 cell line, 1-24 microM) alpha-aminomethyl substituted lactones 3 and 4 were prepared by stereoselective Michael-type addition of amines to alantolactone (1) and isoalantolactone (2). The lactones 1 and 2 and their amine adducts induce apoptosis and act as alkylating agents.
The MeOH extract of the roots of Inula helenium showed a high inhibitory activity for cell growth against MK-1, HeLa and B16F10 cell lines. Significant activity was found in the hexane-soluble fraction. From the hexane-soluble fraction, seven sesquiterpenes, namely, one germacrane (4beta,5alpha-epoxy-1(10),11(13)-germacradiene-8,12-olide), one elemane (igalane), and five eudesmanes (alantolactone, isoalantolactone, 11alpha,13-dihydroalantolactone, 11alpha,13-dihydro-isoalantolactone, 5-epoxyalantolactone) were isolated. In vitro antiproliferative activities of the isolates against MK-1, HeLa and B16F10 cells are reported.
The effect of rose oil inhalation (1.0%, 2.5%, and 5.0% w/w) on the elevated plus-maze (EPM) test was investigated in adult male rats and compared with the effect of diazepam (DZP) (1.0 and 2.0 mg/kg) administered intraperitoneally 30 min before testing. Exposure to rose oil produced an anxiolytic-like effect similar to DZP (anxiolytic reference drug). Thus, at some concentrations, rose oil significantly increased the number of visits to and time spent in the open arms of the EPM. Anxiolytic-like properties of rose oil were observed using the EPM, being consistent with other behavioral and clinical studies.
Aromatherapy is currently used worldwide in the management of chronic pain, depression, anxiety, some cognitive disorders, insomnia and stress-related disorders. Although essential oils have been used, reputedly effectively, for centuries as a traditional medicine, there is very little verified science behind this use. The pharmacology of the essential oils and/or their single chemical constituents, therefore, remains largely undiscovered. However, accumulating evidence that inhaled or dermally applied essential oils enter the blood stream and, in relevant molecular, cellular or animal models, exert measurable psychological effects, indicates that the effects are primarily pharmacological.
This review includes evidence from the limited number of clinical trials that have been published of ‘psychoaromatherapy’ in relation to psychiatric disorders, together with evidence from mechanistic, neuropharmacological studies of the effects of essential oils in relevant in vitro and in vivo models. It is concluded that aromatherapy provides a potentially effective treatment for a range of psychiatric disorders. In addition, taking into account the available information on safety, aromatherapy appears to be without the adverse effects of many conventional psychotropic drugs. Investment in further clinical and scientific research is clearly warranted.
A simple and rapid isocratic reversed-phase high-performance liquid chromatographic method for the quantification of alantolactone/isoalantolactone and three thymol derivatives in roots and root cultures of Inula helenium and I. royleana has been developed. The method could be applied to screen raw materials in search for highly productive plants and in vitro cultures.
To establish a valid animal model of the effects of olfactory stimuli on anxiety, a series of experiments was conducted using rats in an open-field test. Throughout, effects of lavender oil were compared with the effects of chlordiazepoxide (CDP), as a reference anxiolytic with well-known effects on open-field behaviour. Rats were exposed to lavender oil (0.1-1.0 ml) for 30 min (Experiment 1) or 1h (Experiment 2) prior to open-field test and in the open field or injected with CDP (10 mg/kg i.p.). CDP had predicted effects on behaviour, and the higher doses of lavender oil had some effects on behaviour similar to those of CDP. In Experiment 3, various combinations of pre-exposure times and amounts of lavender oil were used. With sufficient exposure time and quantity of lavender the same effects were obtained as in Experiment 2. Experiment 4 demonstrated that these behavioural effects of lavender could be obtained following pre-exposure, even if no oil was present in the open-field test. In Experiments 2-4, lavender oil increased immobility. Together, these experiments suggest that lavender oil does have anxiolytic effects in the open field, but that a sedative effect can also occur at the highest doses.
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