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Gaseous air pollutants
Published in Abhishek Tiwary, Ian Williams, Air Pollution, 2018
Additional natural NMVOC emissions occur from forests; however, we know far less about biogenic VOC (BVOC) emissions than we do about the anthropogenic ones. Plants synthesise many organic molecules as an integral part of their biochemistry – hydrocarbons include hemiterpenes such as isoprene (C5H8), the monoterpenes (C10H16) such as α-pinene and β-pinene, the sesquiterpenes (C15H24) such as humulene. Oxygenated compounds include C1 such as CH3OH, HCHO, C2 such as C2H5OH, and C3 such as acetone (CH3COCH3). Some of these VOCs are released to the atmosphere – the turpentine smell characteristic of pine forests, the monoterpenes from mint and the aldehydes from mown grass are well-known examples. Some information is available about emissions of ethylene (ethene) which regulates physiological processes such as fruit ripening and leaf abscission, and isoprene, but less is known about the rest. The release of BVOCs depends on locational and vegetation parameters (discussed in Chapter 9).
Extraction and Utilisation of Bioactive Compounds from agricultural Waste
Published in Quan V. Vuong, Utilisation of Bioactive Compounds from Agricultural and Food Waste, 2017
Shamina Azeez, C.K. Narayana, H.S. Oberoi
The n-hexane and dichloromethane fractions obtained from sequential extraction of Lophostemon suaveolens, a relatively unexplored endemic medicinal plant of Australia, exhibited antibacterial activity against Streptococcus pyogenes and methicillin sensitive and resistant strains of Staphylococcus aureus. GC-MS analysis of the n-hexane fraction by Naz et al. (2016) showed the presence of the antibacterial compounds, aromadendrene, spathulenol, β-caryophyllene, α-humulene and α-pinene and the anti-inflammatory compounds, β-caryophyllene and spathulenol. Fractionation of the dichloromethane extract led to the isolation of eucalyptin and the known anti-inflammatory compound betulinic acid. The profiles of bioactive compounds (including phenolics and flavonoids in free and bound fractions, anthocyanins, proanthocyanidins, vitamin E, and γ-oryzanol) of outer and inner rice bran from six colored rice samples was obtained using 80 per cent ethanol (Huang and Ng 2012). The authors further reported that the free fraction of the extracts dominated the total phenolics (72–92 per cent) and the total flavonoids (72–96 per cent) of colored rice bran.
Herbal Product Development and Characteristics
Published in Anil K. Sharma, Raj K. Keservani, Surya Prakash Gautam, Herbal Product Development, 2020
Mirian Pateiro, Rubén Domínguez, Predrag Putnik, Danijela Bursać Kovačević, Francisco J. Barba, Paulo S. E. Munekata, Elena Movilla Fierro, José M. Lorenzo
The compounds responsible for the aforementioned properties are mainly (−)-linalool (30%–40%), eugenol (8%–30%), and methyl chavicol (15%–27%), following the importance by (+)-delta-cadinene, 3-carene, α-humulene, citral, and (−)-trans-caryophyllene (Bhattacharyya and Bishayee, 2013; Li and Chang, 2016). Its administration as dietary supplement is often prescribed in the form of pill or capsule, with a recommended dosage from 300 to 2000 mg per day for general preventative purposes. Moreover, a fresh leaf extract, a decoction with hot water, or essential oil form (distilled from leaves and flowers of the plant) can be used to obtained beneficial effects (Mondal et al., 2011).
Varronia verbenacea and Achyrocline satureioides essential oils in granules and microparticles: Stability and in vitro release studies
Published in Drying Technology, 2021
J. C. K. Monteiro Filho, R. A. F. Rodrigues
Among these three marker molecules, fortunately, α-pinene presents the lowest biological efficacy. According to Paula-Freire et al.[17] and Medeiros et al.[18] trans-caryophyllene is intimately related to the anti-inflammatory and antinociceptive effects of these essential oils, as well as the anti-inflammatory effect of α-humulene (already identified as being responsible for the biological action in a commercial product—Acheflan®). In addition to these effects, both molecules act together to exhibit anticancer activity, as reported by El Hadri et al.,[20] indicating their synergistic action. Because of these compounds, the loss of α-pinene could mean not only that the essential oil would remain active, but also that the oils obtained at the end could be enriched and less mass would be required to obtain the same effective dosage.
Use of hop cone extract obtained under supercritical CO2 conditions for producing antibacterial all-purpose cleaners
Published in Green Chemistry Letters and Reviews, 2018
Tomasz Wasilewski, Dominik Czerwonka, Urszula Piotrowska, Artur Seweryn, Zofia Nizioł-Łukaszewska, Marcin Sobczak
Moreover, hop cone extracts contain considerable quantities of natural pigments and fragrances which are beneficial alternatives to their synthetic equivalent. They have a long tradition of use in the perfume industry. They are usually added to formulations with a sharp oriental scent. The main aromatic substances present in hop cone extract are myrcene, α-humulene, (E)-β-farnesene, and trans-β-caryophyllene. The process of supercritical extraction of hop cones yields essential oils which constitute approx. 10% of the extract. One of the key ingredients of the oil is β-myrcene which gives it a sharp scent. Compounds responsible for a much more pleasant resin-like scent include β-caryophyllene and α-humulene (72).
Postharvest blanching and drying of industrial hemp (Cannabis sativa L.) with infrared and hot air heating for enhanced processing efficiency and microbial inactivation
Published in Drying Technology, 2023
Chang Chen, Ke Wang, Ivan Wongso, Zhaokun Ning, Ragab Khir, Daniel Putnam, Irwin R. Donis-González, Zhongli Pan
It was also observed that the composition of terpene compounds in the dried hemp biomass also changed with the drying conditions (Figure 5). The relative contents of β-Myrcene, δ-Limonene, α-Pinenes and β-Pinenes reduced significantly with the increase of drying temperature, while the relative contents of β-Caryophyllene, Caryophyllene Oxide, α-Humulene, and α-Bisabolol increased significantly. These changes should be due to the difference in the molecular structure, volatility and thermal stability of different terpene species. Myrcene, limonene and pinene are monoterpenes with either cyclic or linear conformations and are more volatile and susceptible to thermal processing. Guaiol, humulene, caryophyllene, and bisabolol are sesquiterpenes or sesquiterpenoids with monocyclic or bicyclic conformations, which render them higher boiling point and thermal stability. In general, the higher the average drying temperature, the lower the contents of monoterpene species, and the higher the contents of sesquiterpenes. PCA analysis was applied to evaluate the influence of processing conditions on the terpene profiles in both freshly harvested (represented by freeze-dried sample) and dried hemp samples. The results suggested that PC 1 and PC 2 contributed to 80.87% and 13.30% of the variance, with a cumulative contribution of 94.17% (Figure 6), which adequately covered the data. Compared to the freshly harvested hemp, drying did altered the terpene profiles. Conventional drying resulted in similar terpene profile in the samples as compared to the fresh sample, but with a signature in pinenes, ocimene, caryophyllene and bisabolol. HA and IR processing led to distinct terpene profiles, which remained only the relatively stable sesquiterpenoids in the hemp. Since different terpene species have different aroma profile and pharmaceutical properties, the results suggest that drying methods could be tailored to the needs of the consumers and functionality requirements of potential products.