Introduction to Toxicology
David Woolley, Adam Woolley in Practical Toxicology, 2017
It is not sensible to assume that natural chemicals are safe, just as it is not sensible to assume that a synthetic chemical is inevitably toxic. The website of the American Council on Science and Health (ACSH: http://www.acsh.org) has published a number of items on the presence (in our normal diet) of various chemicals and carcinogens that are found naturally in an everyday diet. The listing included allyl isothiocyanate in broccoli spears, hydrazines in mushroom soup, aniline and caffeic acid in carrots, psoralens in celery, and finally, a long (and incomplete) list of chemicals found in coffee. No one is suggesting that consumption of normal quantities of an everyday diet is going to be associated with unacceptable toxicity, but the list gives some perspective on the relevance of chemical intake and the fact that many toxins cannot be avoided. The ACSH make the point that more than 99% of the chemicals that people ingest occur naturally in a normal diet. However, the chemicals listed on the ACSH website, although safe when eaten in a normal diet, are variously mutagenic and carcinogenic in rodents, associated with contact hypersensitivity and phototoxicity, or are simply toxic when given in their pure form at high concentrations to rodents. If the Delaney clause–a notorious piece of US legislation banning synthetic chemicals from foods if they were shown to cause cancer in animals–were applied to chemicals naturally present in food, our diet would be immediately impoverished and probably unhealthy.
Unique Flavours from Australian Native Plants
Yasmina Sultanbawa, Fazal Sultanbawa in Australian Native Plants, 2017
Tasmannia lanceolata extract has been approved as a GRAS flavouring ingredient FEMA No. 4755, under the conditions of their intended use in food flavourings in accordance with the 1958 Food Additives Amendment to the Federal Food, Drug and Cosmetic Act. The accepted levels as a flavouring substance in food are given in Figure 20.2 (Marnett et al., 2013). Tasmannia lanceolata extract is used in both sweet and savoury products in the food industry. These extracts have also been used as a flavour enhancer in chewing gum to enhance the mint, peppermint and spearmint (Menary et al., 2003). Polygodial has been used in wasabi to enhance the pungent effect of allyl isothiocyanate and interestingly to improve the sensory properties of artificial sweeteners. These effects could be attributed to the pungency and trigeminal stimulatory effect of polygodial (Starkenmann et al., 2011). Polygodial is a good example of the potential uses of pungent molecules in different sensory applications.
Effects of Essential Oils on Human Cognition
K. Hüsnü Can Başer, Gerhard Buchbauer in Handbook of Essential Oils, 2020
Evidence for the influence of physicochemical odorant properties on visual information processing was supplied by Michael and colleagues (Michael et al. 2005). These authors found that the exposure to both allyl isothiocyanate (AIC), a mixed olfactory/trigeminal stimulus, and 2-phenyl ethyl alcohol (2-PEA), a pure olfactory stimulant, impaired performance in a highly demanding visual attention task. The task involved reaction to a target as well as neglecting a distractor that appeared at different time intervals. In trials without a distractor, only 2-PEA significantly increased the reaction times of healthy subjects; in trials with a distractor, subjects reacted more slowly in both odor conditions as compared to the no-odor control condition. However, AIC impaired performance independent of the interval between distractor and target, whereas 2-PEA only had a negative effect when the interval between target and distractor was short. While 2-PEA seemed to have led to performance decrements by decreasing subjects’ arousal levels, AIC as a strong trigeminal irritant seemed to have shifted attention toward the distractor stimuli. A similar observation has also been made for the annoying odor propionic acid (Hey et al. 2009). In this study, the error rate in a response-inhibition task increased as a function of odorant concentration, suggesting a relationship between cognitive distraction and sensory annoyance.
Protective Effect of Allyl Isothiocyanate in an Experimentally Induced Rat Model for Dry Eye Syndrome
Published in Current Eye Research, 2022
Omer Ersin Muz, Cemal Orhan, Mehmet Tuzcu, Besir Er, Abhijeet Ashok Morde, Muralidhara Padigaru, Ibrahim Hanifi Ozercan, Kazim Sahin
Allyl isothiocyanate (AITC) belongs to the family of organosulfur compounds called glucosinolates and is found in mustard, horseradish, and wasabi, providing a pungent flavor.8 AITC is derived from sinigrin, one of the glucosinolate precursors widely found in vegetables and is highly bioavailable through oral administration. AITC has demonstrated potent anti-inflammatory activity by modulating nuclear factor erythroid 2-related factor 2 (Nrf2) and NF-κB signaling pathways and decreasing inflammatory mediators.9,10 Further, AITC has been shown to induce several cellular antioxidant and carcinogen detoxification enzymes, including nicotinamide adenine dinucleotide[phosphate] (NAD[P]H): quinone oxidoreductase-1, glutathione S-transferase, glutamate-cysteine ligase and/or heme-oxygenase 1 in both cultured cells in vitro and animal tissues in vivo.11–16 Given the antioxidative and anti-inflammatory properties of AITC, we hypothesized that AITC treatment in rats with dry eyes induced by benzalkonium chloride (BAC) would reduce the oxidative stress and inflammation of the ocular surface and improve tear volume and tear quality.
An Overview of Hepatocellular Carcinoma with Emphasis on Dietary Products and Herbal Remedies
Published in Nutrition and Cancer, 2022
Deepa S. Mandlik, Satish K. Mandlik
Furthermore, sulforaphane, an isothiocyanate found in broccoli, has been shown to enhance the CYP1A1expression in Hepa 1c1c7 and HepG2 cells in a dose-dependent manner (54). Sulforaphane, on the other hand, was thought to be extremely reactive and converted to N-acetyl-L-cysteine metabolite in human beings. The sulforaphane-N-acetyl-L-cysteine inhibited murine hepatoma cells more effectively and increased the activity of quinone reductase (phase II detoxification enzyme) (55). Allyl-isothiocyanate is formed when sinigrin (an aliphatic glucosinolate) found in cruciferous vegetables, is undergoes hydrolysis. Allyl-isothiocyanate and synthetic N-acetyl-L-cysteine-Allyl-isothiocyanate therapies also inhibited the development of Hepa1c1c7 murine hepatoma cells in a dose-dependent manner. The observed anticancer effects may be due to enhanced mRNA expression of quinine reductase. Furthermore, the treatment of the two compounds inhibited cancer cell adhesion, migration and invasion in human hepatoma cells by downregulating MMP-2/-9 at the transcriptional stage (56). In North Europe and North America, rutabaga (Brassica napobrassica) is a common vegetable. In HepG2 cells, rutabaga extract had selective anti-proliferative and pro-apoptotic activity (57).
Regional brain morphology of the primary somatosensory cortex correlates with spicy food consumption and capsaicin sensitivity
Published in Nutritional Neuroscience, 2023
Pengfei Han, Tao Su, Hong Chen, Thomas Hummel
Consistent with the results from a recent study [12], we observed no association between spicy food intake and odor lateralization score for allyl isothiocyanate or L-menthol odors. The allyl isothiocyanate is perceived as like capsaicin and supposed to activate the TRPV1 receptors [37,38]. In addition, Defrin, Dekel-Steinkeller [39] recently found the higher food spiciness preference was related to low heat-pain sensitivity generalized across the tongue (relevant body region) and the hand (irrelevant body region), suggesting a generalization effect. Hence, the absence of a correlation between spicy food consumption and trigeminal sensitivity may be due to the low volatility of capsaicin and limited amount of other volatile trigeminal compounds released during spicy food consumption. Besides, no association was observed between regional GMV and intranasal trigeminal perception, suggesting that there was little or no top-down effect of brain gray matter morphometry on intranasal trigeminal sensitivity (lateralization ability). The absent correlation also suggests that a change in one part of the trigeminal system does not necessarily result in a change of the responsiveness of entire trigeminal system. This points at a high topographical specificity of the trigeminal system which is also found, for example, in topographical differences in the responsiveness of the intranasal trigeminal system [4,40,41].
Related Knowledge Centers
- Cruciferous Vegetables
- Isothiocyanate
- Horseradish
- Wasabi
- Pungency
- Tears
- Trpa1
- Trpv1
- Rhamphospermum Nigrum
- Mustard Seed