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The biting midge, Forcipomyia taiwana (Shiraki) (Diptera: Ceratopogonidae), can cause severe allergic reactions. It can pass through typical mosquito netting, so repellents are an important control measure against it. This project sought to identify spatial repellents from plants traditionally used by Taiwanese Aboriginal peoples as insect repellents. Fresh plant leaves were collected, frozen, and powdered, and essential oils extracted using hexane then ethyl acetate as solvents. Some commercial oils were also used. The extracts were tested against lab-reared F. taiwana using a Y-tube olfactometer. The composition of the extracts was identified using gas-chromatography mass-spectrometry (GC-MS). Commercial citronella, lavender, and Formosan cypress oils were effective repellents, as were lab-made capillary wormwood and camphor oils. Knockdown was detected in commercial clove leaf, rosemary, common wormwood, and cajuput oils. The oil composition data is the first for many of the Taiwanese plants, many of which contained repellent compounds like caryophyllene, α-pinene, and germacrene D. The results agreed with previous studies on the effects of some plants but differed on others, possibly due differences in plant chemotype, extraction method, and oil concentrations. [ABSTRACT FROM AUTHOR]

Plant-derived natural compounds are desired for their anti-inflammatory properties. We investigated the chemical composition and the anti-inflammatory effects of the essential oil obtained from leaves of the Chinese medicinal plant Artemisia annua L. Artemisia annua L. essential oil (AO) was obtained by hydrodistillation; the extraction yield was approximately 1.2%. Gas chromatography--mass spectrometry (GC-MS) revealed the presence of 13 compounds in AO; the major compounds were caryophyllene (32.16%), eucalyptol (28.62%), α-pinene (19.08%), and β-pinene (14.72%). Cell counting kit-8 (CCK8) assay revealed that AO did not show in vitro cytotoxicity toward RAW264.7 cells and suppressed the expression of nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) in lipopolysaccharide (LPS)-induced RAW264.7 cells. Pretreatment with AO significantly reduced xylene-induced inflammation in the ears of Kunming mice. AO inhibited inflammatory cell infiltration, decreased epidermis thickness in the ear, and suppressed expression of TNF-α in the serum. The in vivo anti-inflammatory activity of AO was similar to that of the positive control compound Di Song Zhang Bo Cream. Overall, AO was observed to be an effective antiinflammatory agent. These results provide an experimental basis for commercializing AO-derived external preparations for pharmacological and cosmetic industries. [ABSTRACT FROM AUTHOR]

In-vitro chemical characterization and mosquitocidal screening of essential oil derived from Mikania scandens (L.) Willd. (Asteraceae) (CVO-MS) against the malarial vector Anopheles gambiae was investigated. GC-MS analysis evidenced a total of 12 bio-active compounds, and maximum at α-bisabolol (39.34%) followed by stigmasterol (13.45%) respectively. The larvicidal activity of CVO-MS against the malarial vector An. gambiae evidenced that the mortality rate was prominent at the maximum dosage of 1000 ppm. The Median Lethal Concentration (LC50) of CVO-MS was established at 488±2.45 ppm, respectively. Enzyme inhibition assay showed that the CVO-MS delivers a significant upsurge in the level of CYP450, GST, and a decline in the level of α-β carboxylesterase activity in both the third and fourth instar (p ≤ 0.0001). The gut-histological examination of CVO-MS showed that there is severe damage in the mid-gut tissues, especially epithelial layer (EL), gut-lumen (GL), and peritrophic membrane (pM). The non-target screening against the mosquito predators (A. bouvieri, D. indicus, and third instar larvae of Tx. splendens) suggests that CVO-MS showed less toxicity as compared to Pestanal® (1 ppm) respectively. The present study has paved a new insight in understanding the bioactivity of CVO-MS as a potential larvicidal agent of malarial vector and non-toxic against mosquito predators. [ABSTRACT FROM AUTHOR]

The essential oils of seeds, peels, and leaves from Limnocitrus littoralis (Miq.) Swingle growing wildly on the southcentral coast of Vietnam were extracted by hydrodistillation method. The yields of the oils were recorded. The organoleptic and physicochemical properties of the oils were defined and evaluated according to international standards at 25 °C. A total of forty-three, fifty, and sixty-five components of these oils were analysed and identified, respectively. Major constituents in the seed oil were ß-pinene (3.7%, Quang Ngai; 24.0%, Ninh Thuan), ß-myrcene (11.1%, Quang Ngai; 59.2%, Ninh Thuan), o-cymene (57.7%, Quang Ngai), and limonene (18.5%, Quang Ngai; 94.5%, Phu Yen; 8.5%, Ninh Thuan). Major constituents in the peel oil included a-pinene (11.3%, Ninh Thuan), ß-pinene (3.9%, Quang Ngai; 62.6%, Ninh Thuan), and limonene (54.0%, Quang Ngai; 94.0%, Phu Yen; 3.5%, Ninh Thuan). Major constituents in the leaf oils consisted of ß-pinene (36.4%, Ninh Thuan), ß-myrcene (38.0%, Quang Ngai; 28.9%, Ninh Thuan), and limonene (17.3%, Quang Ngai; 93.2%, Phu Yen). This research highlighted the aromatic value of bearing oil plants growing wildly on the Southcentral coast of Vietnam. [ABSTRACT FROM AUTHOR]

The contamination of foods with aflatoxins, a group of carcinogenic compounds produced by some filamentous fungi belonging to Aspergillus section Flavi, is the major food safety concern worldwide. Various pre- and post-harvest techniques have been employed to minimize the level of aflatoxins in food commodities. The present study aimed to explore the potential of essential oils (EOs) derived from the medicinal herbs viz., Heliotropium bacciferum, Ocimum dhofarense and Zataria multiflora to detoxify aflatoxin B1 (AFB1). The EOs extracted from H. bacciferum, O. dhofarense and Z. multiflora exhibited 82.6, 92.0 and 67.9% degradation of AFB1, respectively as determined by ELISA. In the laboratory tests, EO of Z. multiflora was very effective in inhibiting the growth of Aspegillus flavus, whereas EOs of H. bacciferum and O. dhofarense did not show inhibitory activity towards A. flavus. Gas chromatography-mass spectrometry analysis of the EOs showed the presence of α-pinene (32.9%) and β-myrcene (9.4%) in H. bacciferum, germacrene D (41%), bicyclogermacrene (16.4%) and germacrene B (13.7%) in O. dhofarense and linalool (27.5%) and bornyl acetate (15.4%) in Z. multiflora as the major components. To our knowledge, this is the first study demonstrating detoxification of AFB1 by EOs of medicinal plants. [ABSTRACT FROM AUTHOR]

A commercial herbal oil with different bottle materials on the Indonesian markets was studied. The effects of the different specimens viz. PET-new, PET-open, and AL-new on the main antibacterial components of herbal oil were investigated. Step-1, analysis of antibacterial activity (against S. aureus and E. coli) and testing of non-toxic (in-vivo). Step-2, detection of the main antibacterial compounds (6 types) during the storage times. The market and environmental aspects were also considered. The results, all specimens had antibacterial activity and they showed non-toxic. At the 0-month, six types of main antibacterial compounds were detected in all specimens. The longer the storage time, the more main antibacterial compounds were lost. The most loss (4 types) was observed in AL-new (12-months) and PET-open. PET-new showed the least loss (1 type) at 6-months and 12-months, namely eugenol. Interestingly, PET-new was able to retain curcumene, farnesol, and p-cymene for up to 12 months of storage. PET-new was also more economical (8.7% cheaper) and environmental-friendly than AL-new. The sprayer cap types are strongly recommended for PET herbal oil packaging. [ABSTRACT FROM AUTHOR]