Tenebrio molitor beetles have been widely used in traditional and folklore medicines to treat various human diseases worldwide. This study was performed to determine radical scavenging activity of nine compounds that were extracted from T. molitor adults and their 64 related compounds using a 2,2-diphenyl-1-picrylhydrazyl assay. The results were compared with those of three positive controls, ascorbic acid, butylated hydroxytoluene (BHT), and epigallocatechin gallate (EGCG). Based on IC50 values, linolenic acid (77.65 μM) was the most potent antioxidant and the antioxidant activity of this compound was higher than that of either ascorbic acid, BHT or EGCG. The antioxidant activity of protocatechuic acid (IC50, 153.68 μM) and ascorbic acid did not differ significantly. The antioxidant activity of catechin (IC50, 192.32 μM) was higher than that of either BHT or EGCG. Multiple regression analysis of the antioxidant activities of compounds was examined using their IC50 values and the values of the physical parameters (molecular weight (MW), log P, and molecular refraction (MR)) for the 41 fatty acids (R2 = 0.729 (P = 0.031)) and 29 flavonoids (R2 = 0.521 (P = 0.054)). Correlation coefficient (r) analysis showed that MW, log P, and MR may be positively correlated with IC50 of the fatty acids (MW, r = 0.743; log P, r = 0.642; and MR, r = 0.815) and IC50 of the flavonoids (MW, r = 0.642; log P, r = 0.495; and MR, r = 0.643). Further studies will warrant possible applications of T. molitor adults as an antioxidant.

Bee pollen have been used for centuries as a kind of traditional medicine and food diets additive due to their nutritional and biological properties. The present study was to evaluate the biological features of ethanol extracts of 18 different bee pollen (EEBP) samples collected from 16 locations of South Korea. Our results indicated most of the EEBP samples showed 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, inhibitory activities against human β-amyloid precursor cleavage enzyme (BACE-1), and antiproliferative activities towards five cancer cell lines. However, these EEBP samples did not present human acetylcholinesterase (AChE) inhibitory activities, and intestinal bacteria growth inhibitory activities.

The American house dust mite, Dermatophagoides farinae Hughes, 1961 (Acari: Pyroglyphidae), is recognized as an important source of allergens in the domestic environment. An assessment was made of the toxicity of constituents from essential oil of cade, Juniperus oxycedrus L. (Cupressaceae), and related compounds as well as four experimental spray formulations containing the oil (10–40 g/liter sprays) to adult D. farinae. In a contact + fumigant mortality bioassay, methyleugenol (24-h LC50,5.82 μg/cm2) and guaiacol (8.24 μg/cm2) were the most toxic constituents to the mites and the toxicity of these constituents and benzyl benzoate did not differ significantly.

The human β-amyloid (Aβ) cleaving enzyme (BACE-1) is a target for Alzheimer’s disease (AD) treatments. This study was conducted to determine if acacetin extracted from the whole Agastache rugosa plants had anti-BACE-1 and behavioral activities in Drosophila AD models and to determine acacetin’s mechanism of action. Acacetin (100, 300, and 500 μM) rescued amyloid precursor protein (APP)/BACE1-expressing flies and kept them from developing both eye morphology (dark deposits, ommatidial collapse and fusion, and the absence of ommatidial bristles) and behavioral (motor abnormalities) defects. The RT-PCR and Western blot analysis revealed that the protective effect of acacetin on Aβ production is mediated by transcriptional regulation of BACE-1 and APP, resulting in decreased APP protein expression and BACE-1 activity, and reduced Aβ production by interfering with BACE-1 activity and APP synthesis, resulting in a decrease in the levels of the APP carboxy terminal fragments and the APP intracellular domain, and finally, resulting in a decrease in the number of amyloid plaques.

Aedes aegypti and Aedes albopictus and Culex pipiens pallens mosquitoes transmit dengue fever and West Nile virus diseases, respectively. This study was conducted to determine the toxicity and mechanism of action of four flavonoids and seven fatty acids from Millettia pinnata (Fabaceae) seed as well as four fatty acid esters toward third instar larvae from insecticide-susceptible C. p. pallens and A. aegypti as well as wild A. albopictus. Potent toxicity was produced by karanjin, oleic acid, karanjachromene, linoleic acid, linolenic acid, pongamol, pongarotene, and elaidic acid toward C. p. pallens larvae (24 h LC50, 14.61–28.22 mg/L) and A. aegypti larvae (16.13–37.61 mg/L). Against wild A. albopictus larvae, oleic acid (LC50, 18.79 mg/L) and karanjin (35.26 mg/L) exhibited potent toxicity. Acetylcholinesterase (AChE) is the main site of action of the flavonoids, oleic acid, and palmitic acid.,Linoleic acid and linolenic acid might act on both AChE and octopaminergic receptor. Further studies will warrant possible applications of M. pinnata seed-derived products as potential larvicides for the control of mosquito populations.

Propolis collected from botanical sources by honey bee, has been used as a popular natural remedies in folk medicine throughout the world. This study was conducted to assess growth inhibitory effects of ethanol extracts of propolis (EEPs) from 20 different regions in South Korea on human intestinal bacteria as well as BACE-1, AChE inhibitory, antioxidant, antiproliferative, and anti-human rhinovirus activities. Correlation coefficient (r) analysis of the biological activities of EEP samples was determined using their 50% inhibition concentration or minimal inhibitory concentration values and their polyphenol or flavonoid contents in 20 Korean EEP samples. Correlation coefficient analysis showed that total polyphenol contents may be negatively correlated with DPPH free radical scavenging activity (r = –0.872) and total flavonoid content has no correlation with the activity (r = 0.071). No direct correlation between BACE-1 inhibition, AChE inhibition, or antiproliferative activity and total polyphenol or total flavonoid content in Korean EEP samples was found.

This study was conducted to determine the toxicity to adult Myzus persicae (Sulzer) and Aphis gossypii Glover of 88 plant essential oils and six experimental spray formulations containing bitter orange or marjoram oil was examined using the vapor-phase mortality and spray bioassays. Results were compared with those of two conventional insecticides deltamethrin and dichlorvos. As judged by 24 h LC50 values, bitter orange oil (0.0212 and 0.0192 mg/cm3) was the most active material, followed by marjoram, celeryseed, and cypress oils (0.0239-0.0508 and 0.0209-0.0542 mg/cm3). These essential oils were significantly less toxic than dichlorvos, respectively. These essential oils were consistently more toxic to adult M. persicae in closed versus open containers, indicating that toxicity was achieved mainly through the action of vapor. Bitter orange oil and marjoram oil applied as 1% spray provided complete mortality toward two aphid species adults. Reasonable aphid control in greenhouses can be achieved by a spray formulation containing the 1% oil as potential contact-action fumigant.

The toxicity of cade oil (Juniperus oxycedrus), its constituents and structurally related compounds toward adult house dust mite Dermatophagoides farina was examined. Results were compared with two commercially available acaricides, benzyl benzoate and deet. The cade oil constituents were identified by GC-MS analysis. Citral (LC50, 1.13 μg cm–2) and methyleugenol (LC50, 5.78 μg cm–2) were the most toxic compounds, followed by eugenol (LC50,12.52 μg cm–2), nerol (LC50, 21.4 μg cm–2) and terpinen-4-ol (LC50, 29.55 μg cm–2) were shown significant mortality against adult of D. farina. Toxicity of citral, methyleugenol were higher than that of benzyl benzoate, and above listed compounds was all more toxic than deet. Given the result of vapour-phase mortality tests that these compounds were more toxic in closed containers than in open ones, we concluded that vapour action plays a great role in their mode of delivery. Cade applied as 3 and 4% experimental sprays provided 96 and 100% mortality against the mites respectively, whereas permethrin (cis:trans, 25:75) 2.5 g/l spray treatment resulted in 17% mortality. Cade oil, and its constituents shown their potentials as effective alternatives for harmful synthetic acaricides for the control of Dermatophagoides populations as fumigants in contact and therefore illustrated the need for further study of this essential oil.

An assessment is made of the anti-proliferative activity of cicada slough-derived materials against 10 human cancer cell lines, including PC-3 and DU145 prostate cancer cell lines, using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results were compared with those of the commercially available anticancer agent with broad spectrum cisplatin. The ethanol extract of Cryptotympana spp. slough was proved to have anti-proliferative activity against A549 lung, AGS stomach, PC-3 and DU145 prostate, Hela cervix, HT-29 colon, MCF-7 breast, and SK-Hep-1 liver cancer cell lines except for Hep-2 larynx and SK-OV-3 ovary cancer cell lines. The biologically active constituent was characterized as the nonprotein α-amino acid theanine [2-amino-4-(ethylcarbamoyl)butyric acid] by spectroscopic analysis, including EI-MS and NMR. Theanine was isolated from the cicada slough as a new cytotoxic principle. Fifty percent inhibition concentration (IC50) values of the constituent against PC-3 was 6.52 μg/mL, respectively. The activity of theanine (IC50,6.52μg/mL) did not differ significantly from that of the anticancer agent cisplatin (IC50,7.39μg/mL) toward PC-3. In conclusion, further studies on the cicada slough-derived materials containing theanine as potential anticancer products or a lead molecule for the prevention or eradication from human prostate cancer.

Lung cancer caused by diverse changes in cells resulted by exposure to carcinogens found in tobacco smoke, the environment, or sequential accumulation of genetic changes to the normal epithelial cells of the lung. An assessment was made of the anti-proliferative activity of constituents from silkworm feces against 11 human cancer cell lines, including A549 and H727 lung cancer cell lines, using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The ethanol extract of silkworm feces was proved to have anti-proliferative activity against all 11 species of human cancer cell lines. The biologically active constituent was characterized as vomifoliol (blumenol A) (1) and stigmasterol (2) by spectroscopic analysis ,including MS and NMR. In conclusion, global efforts to reduce the level of antitcancer agents justify further studies on the silkworm feces-derived materials containing vomifoliol and stigmasterol as potential anticancer products or lead compounds for the prevention or eradication from human lung cancer.

The toxicity of bay leaf (Pimenta racemosa) and palmorasa (Cymbopogon martini) essential oils, and its constituents, and structurally related compounds to adult American house dust mites, Dermatophagoides farinae was examined. Both bay leaf (24 h LC50, 131.95 μg/cm2) and palmorosa (24 h LC50, 116.10 μg/cm2) essential oils were toxic to mites. The most active principles were determined to be citral, methyleugenol, eugenol, and geranyl acetate from both bay leaf and palmorosa oils. Citral (24 h LC50, 1.13 μg/cm2), methyl eugenol (5.78 μg/cm2), eugenol (24 h LC50, 12.52 μg/cm2) and geranyl acetate (24 h LC50, 18.79 μg/cm2) were the most toxic. The toxicity of these compounds was more toxic than that of commercially available acaricides such as, benzylbenzoate (LC50,8.41μg/cm2) and deet (37.67 μg/cm2). Potent toxicity was also observed with nerol, linalool and geraniol (LC50, 21.44–54.61 μg/cm2). These compounds were consistently more toxic in closed versus open containers, indicating that their mode of delivery was largely a result of vapour action. Both bay leaf and palmorosa oil, and their constituents shown their potentials as effective alternatives for harmful synthetic acaricides for the control of Dermatophagoides populations as fumigants in contact and therefore illustrated the need for further study of these essential oils.

An assessment was made of the toxicity of basil, Ocimum basilicum, essential oil, 11 basil oil constituents, seven structurally related compounds and another 22 previously known basil oil constituents and the control efficacy of four experimental spray formulations containing the oil (1, 2, 3 and 4% sprays) to adult American house dust mites, Dermatophagoides farinae. Results were compared with those of two conventional acaricides benzyl benzoate and N,N-diethyl-3- methylbenzamide (deet). The active principles were determined to be citral, α -terpineol and linalool. Citral (24 h LC50, 1.13 μg/cm2) and menthol (1.69 μg/cm2) were the most toxic compounds, followed by methyl eugenol (5.78 μg/cm2). The toxicity of these compounds was more toxic than that of benzylbenzoate(LC50, 8.41 μg/cm2) and deet (37.67 μg/cm2). These compounds were consistently more toxic in closed versus open containers, indicating that their mode of delivery was largely a result of vapour action. Basil applied as 3 and 4% experimental sprays provided 97 and 100% mortality against the mites respectively, whereas permethrin (cis:trans, 25:75) 2.5 g/l spray treatment resulted in 17% mortality. Reasonable mite control in indoor environments can be achieved by spray formulations containing the basil oil (3 and 4% sprays) as potential contact-action fumigants.

The toxicity of red pine needle hydrodistillate, its constituents, and 12 structurally related compounds to third instar larvae of insecticide-susceptible Aedes aegypti and wild Aedes albopictus was examined using a direct-contact bioassay. Results were compared with those of the currently used larvicides fenthion and temephos. The red pine needle hydrodistillate constituents were identified by GC-MS and co-elution of authenticated samples following co-injection. Based on 24 h LC50 values, 3-carene (8.60–9.33 mg/L), limonene (10.34–10.77 mg/L), and thymol (10.65–11.45 mg/L) were the most toxic constituents. The moderate toxicity was produced by (1S)-(–)-α-pinene, p-cymene, geranyl acetate, myrcene, and β -caryophyllene (LC50, 27.62–38.01 and 28.61–39.52 mg/L). Overall, these compounds were less effective than either fenthion (LC50, 0.012–0.022 mg/L) or temephos (LC50, 0.010–0.015 mg/L). In the light of global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment, red pine needle hydrodistillate and the compounds described merit further study as potential larvicides for the control of mosquito populations.

An assessment was made of the toxicity of hiba, Thujopsis dolabrata var. hondai, oil and 24 oil constituents and control efficacy of four experimental spray formulations containing the oil (0.5. 1, 2, and 3% sprays) to adult American house dust mite (AHDM), Dermatophagoides farinae, and copra mite (CM), Tyrophagus putrescentiae. Results were compared with those of three conventional acaricides benzyl benzoate, N,N-diethyl-3-methylbenzamide (deet), and permethrin. Based on 24 h LC50 values, (–)-thujopsene was the most toxic constituent against AHDM (9.82 μg/cm2) and CM (10.92 μg/cm2) and the toxicity of the compound was nearly identical to that of benzyl benzoate (9.33 and 10.14 μg/cm2). High toxicity was also observed with (–)-(E)-pinocarveol, carvacrol, (+)-terpinen-4-ol, β-thujaplicin, cedrol, α-terpineol, (+)-ledene, thymol, and 2,4-di-tert-butylphenol against both mite species (LC50, 11.92–19.19 and 12.49–22.97 μg/cm2). These constituents were more toxic than deet (LC50, 35.53 and 38.42 μg/cm2). Hiba applied as 2 and 3% sprays provided >95% mortality against both mite species, whereas permethrin (cis:trans, 25:75) 2.5 g/L spray treatment resulted in ca 11% mortality. Global efforts to reduce the level of highly toxic synthetic acaricides in indoor environments justify further studies on hiba oil preparations containing the constituents described as potential contact-action fumigants or lead molecules for the control of mite populations.

The yellow fever mosquito, Aedes aegypti, is a vector for transmitting dengue fever and yellow fever. An assessment was made of the histopathological and molecular effects of pellitorine, an isobutylamide alkaloid, on third instar Ae. aegypti larvae. At 5 mg/L concentration of pellitorine, whole body of the treated larvae became dark in color, particularly damaged thorax and abdominal regions. Pellitorine targeted mainly on midgut epithelium and anal gills, indicating variably dramatic degenerative responses of the midgut through a sequential epithelial disorganization. The anterior and posterior midgut was entirely necrosed, bearing only gut lumen residues inside the peritrophic membranes. Pellitorine caused comprehensive damage of anal gill cells and branches of tracheole and the debris was found in hemolymph of anal gills. RT-PCR analysis indicates that the compound inhibited gene expression encoding V-type H+-ATPase and aquaporine 4 after treatment with 2.21 mg/L pellitorine. The results provide a fact that pellitorine merits further study as a potential larvicide with a specific target site or a lead molecule for the control of mosquito populations.

The toxicity of materials derived from the seed of Pongamia pinnata to third instars of insecticide-susceptible Culex pipiens pallens and Aedes aegypti and wild Aedes albopictus was examined using a direct contact bioassay. Results were compared with those of the currently used insecticides fenthion and temephos. The active principles of Pongamia pinnata were identified as the karanjin (1), karanjachromene (2), pongamol (3), pongarotene (4), oleic acid (5), and palmitic acid (6) by spectroscopic analysis. Based on 24 h LC50 values, karanjin (14.61 and 16.13 mg/L) was the most toxic compound, followed by oleic acid (18.07 and 18.45 mg/L) and karanjachromene (18.74 and 20.57 mg/L). These constituents were less toxic than either fenthion (LC50, 0.0031 and 0.0048 mg/L) or temephos (0.021 and 0.050 mg/L) against Ae. aegypti and Cx. p. pallens. Low toxicity was produced by pongamol (LC50, 23.95 and 25.76 mg/L), pongarotene (25.52 and 37.61 mg/L), and palmitic acid (34.50 and 42.96 mg/L). Against A. alpopictus instars, oleic acid (LC50, 18.79 mg/L) was most toxic. Low toxicity was observed with the other five constituents (LC50, 35.26- 85.61 mg/L). P. pinnata seed-derived active principles, particularly karanjin, karanjachromene, and oleic acid, merits further study as potential mosquito larvicides for the control of mosquito populations in light of global efforts to reduce the level of highly toxic synthetic larvicides in the aquatic environment.

The toxicity of 102 plant essential oils against third instars of cecidomyiid gall midge, Camptomyia corticalis, was examined using a vapor-phase mortality bioassay. Results were compared with that of a conventional insecticide dichlorvos. Based on 24 h LC50 values, all essential oils were less toxic than dichlorvos (LC50, 0.027 mg/cm3). The LC50 of caraway seed, armoise, sage (Clary), oreganum, lemongrass, niaouli, spearmint, cassia special, sage (Dalmatian), thyme red, bay, garlic, and pennyroyal essential oil is between 0.55–0.60 mg/cm3. The LC50 of cassia pure, thyme white, cassia redistilled, star anise, peppermint, wintergreen, cinnamon bark, majoram, chamomile romon, eucalyptus, rosemary, cedar wood, pimento berry, savory (summer), lavender, and coriander oil is between 0.61–0.99 mg/cm3. All other essential oils tested exhibited low toxicity to the cecidomyiid larvae (LC50,>0.99 mg/cm3). The active principles of active essential oils were identified by GC-MS analysis. The major active principles are such as pulegone, thujone, camphor, 1,8-cineole, a-pinene, thymol, menthol. At a rate of 5 mg/cm3, pulegone, and thujone, exhibited 100% morality whereas camphor, 1,8-cineole, α-pinene, thymol and menthol showed 90% mortality at 15 mg/cm3. Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on the essential oils and their constituents described as potential insecticides for the control of the mushroom fly as fumigants with contact action.

The larvicidal activity of 104 plant essential oils and their major constituents against third instar larvae of mushroom fly Camptomyia corticalis was examined using a vapor-phase mortality bioassay. Results were compared with those of the conventional insecticides dichlorvos. Over ten plant essential oils exhibited showed more than 90% mortality. At a rate of 0.2 mg/cm3 air, pulegone, and thujone, exhibited 100% morality whereas camphor, 1,8-cineole, α-pinene, thymol and menthol showed 90% mortality at 0.6 mg/cm3 air. Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on the essential oils and their constituents described as potential insecticides for the control of the mushroom fly as fumigants with contact action.

The repellency of 104 plant essential oils to female Aedes aegypti was examined using a cage-distribution assay. Results were compared with those of the conventional mosquito repellent N,N-diethyl-m-toluamide (DEET). Coriander, oreganum, pennyroyal, lemoneucalyptus, and spearmint exhibited high repellency effect (>60 minutes at 50 mg/filter paper), followed by sage, leavander, tarragon, bergamot, and neroli oils which showed moderate effective (< 40 minutes at 50 mg/filter paper (5 cm diameter)). In the light of global efforts to reduce the level of highly toxic synthetic repellents, essential oils described merit further study as potential repellents for the control of mosquito populations.

The toxicity of materials derived from seed of Pongamia pinnata Pierre toward to third instar larvae of Aedes aegypti and Culex pipiens pallens was examined using direct contact bioassay. Results were compared with those of the currently used insecticides: fenthion and temephos. The active principles of Pongamia pinnata were identified as the karanjin (1), pongamone (2), palmitic acid (3) and karanjachromene (4), by spectroscopic analysis. Based on 24h LC50 values, karanjin (14.61 and 16.13 ppm) was the most toxic compound but less effective than fenthion (0.0031 and 0.068 ppm) and temephos (0.016 and 0.056 ppm) against Ae. aegypti and Cx p. pallens. Moderate toxicity was produced by pongamone (34.50 and 39.53 ppm), palmitic acid (36.93 and 42.96 ppm), and karanjachromene (43.05 and 48.95 ppm). P. pinnata seed derived materials, particularly karanjin, merit further study as potential mosquito larvicides for the control of mosquito populations in light of global efforts to reduce the level of highly toxic synthetic larvicides in the aquatic environment