Juvenoid Activity Research Articles

Qualitative structure-activity relationships of aryl isoprenoid derivatives as biorational juvenoids - reweighing.

The online version contains supplementary material available at 10.1007/s42690-023-01025-3.

Hibiscus Rosa Sinensis Linn.

Hibiscus Rosa Sinensis Linn. (Malvaceae) is a popular medicinal plant found in tropical and sub-tropical region of world. All plant parts of Hibiscus Rosa Sinensis Linn are most widely used to treat several ailments like anti-Tumor, anti-fertility, anti-ovultory, anti-implantation, anti-Inflammatory, analgesic, anti-estrogenic, anti-pyretic, anti-spasmodic, anti-viral, anti-fungal, anti-bacterial, hypoglycemic, spasmolytic, CNS depressant, hypertensive and juvenoid Activity. Due to its multidimensional pharmacological approach it is certain to emerge as a effficient player in the flourising field of herbal supplements, medicines and health care system. This review aims to present recent details on botany, ethnomedicinal uses, photochemistry, pharmacological effects, toxic effects, with the purpose to find research gaps demanding for upcoming research and investigation of Hibiscus Rosa Sinensis Linn. Principal constituents reported in Hibiscus Rosa Sinensis Linn are flavones, containing quercetin-3-sophorotrioside, kaempferol-3xylosylglucoside,quercetin-3-diglucoside, quercetin-3,7-diglucoside, cyaniding-3,5-diglucoside, cyaniding-3-sophoroside-5-glucoside and other constituent are cyanidin chloride, cyclopeptide alkaloid, ascorbic acid, riboflavin, thiamine, hentriacontane, taraxeryl acetate, ß-sitosterol, malvalic acids and cyclic acids sterculic. Complete literature was probed via websites,online databases, thesis and texts. The available reports was portray physicochemical parameters, nutritional aspects and phytochemical analysis of bioactive plant parts. Friendly holistic conservation approaches offered by plant biotechnology applications are also discussed.

Conventional and Organic Wheat Germ Have Distinct Physiological Effects in the Tobacco Hornworm, Manduca Sexta: Use of Black Mutant Assay to Detect Environmental Juvenoid Activity of Insect Growth Regulators.

Stored grains used in artificial diets are often treated with insecticides to control infestation by pests. In recent years, insect growth regulators (IGRs) have become an increasingly popular form of insect pest control in agricultural settings. Most IGRs specifically target insects by either disrupting their endocrine system or their chitin synthesis. One type of IGRs comprises of chemical analogs of juvenile hormone (JH), a major hormone involved in growth and development of insects. Here we demonstrate that conventional wheat germ contains JH activity and impacts growth and development of the tobacco hornworm, Manduca sexta. Feeding diet containing conventional wheat germ delayed the timing of metamorphosis in wildtype larvae by extending the duration of the final instar. Diet with conventional wheat germ also inhibited melanization of the black mutant larvae and induced the expression of the JH response gene, Krüppel homolog 1. We demonstrate that the black mutant bioassay is a sensitive assay that can determine the amount of JH activity in stored grains and suggest that this assay may offer a quick and reliable assay to determine the amount of environmental juvenoids. Researchers are urged to use caution when purchasing stored grains for mass-rearing of research insects.

Comparison in the response of three European Gammarid species exposed to the growth regulator insecticide fenoxycarb.

Growth regulator insecticides with juvenoid activity can affect the development and reproduction of non-target organisms such as crustaceans. In this perspective, our previous studies revealed deleterious effects of the juvenoid fenoxycarb at 5μgL-1 on the embryogenesis and at 50μgL-1 on the reproductive behavior of the amphipod Gammarus fossarum. In the present study, to determine whether data generated with one amphipod species can be extended to other gammarid species, we tested the effects of a 5μgL-1 fenoxycarb exposure on three European amphipod species: G. fossarum, Gammarus roeseli, and Echinogammarus longisetosus. We exposed individually 60 freshly fertilized females to fenoxycarb throughout the entire oogenesis/embryogenesis cycle (i.e., 19days). In newborn individuals from exposed embryos, we measured both pigmentation and lipid reserve impairments while in exposed females, we observed reproductive behavior. At 5μgL-1 fenoxycarb, reproductive behavior was only altered in G. fossarum. This study demonstrates the variability of the toxic response among the three gammaridae species, underlining the need for acquiring data with a broad phylogenetic representation to better predict toxic effects on freshwater ecosystems.

UTILIZATION OF THE TOPICAL APPLICATION OF LIMONENE TO THE FIFTH INSTAR LARVAE OF THE SILKWORM,BOMBYX MORI (L.) (RACE: PM X CSR2) FOR THE PARAMETERS OF LARVAE, COCOON AND SILK FILAMENT

The attempt is concerned with topical application of the limonene on the fifth instar larvae of multivoltine silkworm, Bombyx mori (L.). The ten microliters of one milligram per liter strength acetone solution of limonene was topically applied to the individual fifth instar larvae of multi voltine cross breed race of silkworm, Bombyx mori (L.) (PM x CSR2) variously at 48, 54, 60 and 66 hours after the fourth moult. Topical application of acetone solution of limonene was found variously reflected into prolongation of larval age (23.129-38.775%); improvement in the tissue somatic index (TSI) of silk glands (3.041-7.761); cocoon shell ratio (2.828-4.497); Tex of silk filament (0.038-0.107) and denier scale of silk filament (0.343- 0.962). Topical application of acetone solution of limonene, thus chiefly lengthen the larval age in silkworm, Bombyx mori (L.). Time required for eating and amount of mulberry leaves eaten had both been increased and they were practically reflected into the improvement in the quality of cocoon and the silk filament. The terpenoid nature of limonene and delay in the spinning among the larvae, recipient of this limonene in the attempt indicate the possibility of it’s insect juvenoid activity in silkworm, Bombyx mori (L.). Efficient utilization of limonene, the terpene compound through acetone solvent for topical application to the fifth instared larvae of silkworm, Bombyx mori (L.) may open a biotechnological avenue in the sericulture industries.

UTILIZATION OF THE TOPICAL APPLICATION OF LIMONENE TO THE FIFTH INSTAR LARVAE OF THE SILKWORM,BOMBYX MORI (L.) (RACE: PM X CSR2) FOR THE PARAMETERS OF LARVAE, COCOON AND SILK FILAMENT

The attempt is concerned with topical application of the limonene on the fifth instar larvae of multivoltine silkworm, Bombyx mori (L.). The ten microliters of one milligram per liter strength acetone solution of limonene was topically applied to the individual fifth instar larvae of multi voltine cross breed race of silkworm, Bombyx mori (L.) (PM x CSR2) variously at 48, 54, 60 and 66 hours after the fourth moult. Topical application of acetone solution of limonene was found variously reflected into prolongation of larval age (23.129-38.775%); improvement in the tissue somatic index (TSI) of silk glands (3.041-7.761); cocoon shell ratio (2.828-4.497); Tex of silk filament (0.038-0.107) and denier scale of silk filament (0.343- 0.962). Topical application of acetone solution of limonene, thus chiefly lengthen the larval age in silkworm, Bombyx mori (L.). Time required for eating and amount of mulberry leaves eaten had both been increased and they were practically reflected into the improvement in the quality of cocoon and the silk filament. The terpenoid nature of limonene and delay in the spinning among the larvae, recipient of this limonene in the attempt indicate the possibility of it’s insect juvenoid activity in silkworm, Bombyx mori (L.). Efficient utilization of limonene, the terpene compound through acetone solvent for topical application to the fifth instared larvae of silkworm, Bombyx mori (L.) may open a biotechnological avenue in the sericulture industries.

Bioassays of compounds with potential juvenoid activity on Drosophila melanogaster: Juvenile hormone III, bisepoxide juvenile hormone III and methyl farnesoates

Metabolites of the 6,7,10,11 bisepoxide juvenile hormone III (JHB 3), and other potential juvenoids, were tested for juvenile hormone activity using early instar or early stage pupae of Drosophila melanogaster. Importantly, methyl farnesoates were tested as they might have JH-like activity on Dipteran juveniles. Larvae were exposed to compounds in medium, or the compounds were applied to white puparia. In the assays employed in the present study, there was no indication for JH activity associated with the metabolites of JHB 3. The activity of methyl farnesoate (MF) was higher than that of JH III and far greater than bisepoxide JH III. As opposed to the two endogenous juvenile hormones, methyl farnesoate has weak activity in the white puparial bioassay. When fluorinated forms of methyl farnesoate, which is unlikely to be converted to JH, were applied to Drosophila medium to which fly eggs were introduced, there was a high degree of larval mortality, but no evidence of subsequent mortality at the pupal stage. One possible explanation for the results is that methyl farnesoate is active as a hormone in larval stages, but has little activity at the pupal stage where only juvenile hormone has a major effect.

Assessment of the pesticides atrazine, endosulfan sulphate and chlorpyrifos for juvenoid-related endocrine activity using Daphnia magna

The water flea Daphnia magna belongs to the cyclical parthenogenic species, which can reproduce by either parthenogenesis or sexual reproduction. Recent studies have reported the involvement of the methylfarnesoate hormone, in male sex determination of D. magna. The aim of this study was to evaluate the juvenoid and anti-juvenoid activity of atrazine, endosulfan sulphate, and chlorpyrifos. To assess the juvenoid activity we exposed maternal daphnids to several concentrations of the respective pesticides, using the percentage of male production as endpoint. Fenoxycarb (1 μg L −1) was used as a positive control. The anti-juvenoid activity was assessed using a similar bioassay after the addition of fenoxycarb (1 μg L −1) to all test solutions. Fenoxycarb is an insect growth regulator that mimics the action of methylfarnesoate, and promoted the production of 95% of male offspring at the given concentration. Weak juvenoid-agonist activity was detected for endosulfan sulphate, with a significant increase of the percentage of male daphnids detected through logistic regression. In addition, atrazine and endosulfan sulphate antagonized the juvenoid activity of fenoxycarb. These results also corroborate the hypothesis that weak juvenoid agonists can simultaneously act as juvenoid antagonists as it has been observed in other hormonal systems.

A candidate juvenoid hormone receptor cis-element in the Daphnia magna hb2 hemoglobin gene promoter

Hemoglobin levels are significantly elevated in the crustacean Daphnia magna by juvenoid hormones. The present study was undertaken to identify the specific globin (hb) genes that are induced by juvenoids and to identify putative juvenoid response elements (JREs) that may mediate this induction. Gene product of globin 2 (hb2), but not globin 1 and globin 3, was robustly elevated following juvenoid treatment of daphnids. A candidate JRE, located in the promoter of hb2, bound activated factor(s) in response to juvenoid treatment of daphnids. This hormone-induced protein:JRE interaction was robust when daphnids were reared at high oxygen tension but was inhibited when daphnids were reared under low pO 2, implying that hypoxia might act to disrupt juvenoid-mediated endocrine signaling. The candidate JRE consists of a steroid/retinoid-response element-like core adjacent to a 5′ AT-rich extension and thus bears resemblance to response elements that bind monomeric nuclear receptors. The induction of hb2 mRNA levels by juvenoid treatment occurred rapidly (within 4 h of exposure) and was not attenuated by treatment of daphnids with cycloheximide. In contrast, cycloheximide treatment did block hormone-mediated elevations in hemoglobin protein levels. Thus, induction of hb2 by juvenoids was not dependent upon the synthesis of secondary transcription factors that bound the JRE but was likely due to activation of the gene directly by the juvenoid-receptor complex. Affinity pull-down experiments with nuclear proteins extracted from juvenoid-treated daphnids using the JRE as bait yielded a 52 kDa candidate for a monomeric nuclear receptor in D. magna that may mediate the regulatory activity of juvenoids.

The screening of chemicals for juvenoid-related endocrine activity using the water flea Daphnia magna

U.S. Environmental Protection Agency is charged with developing a screening and testing paradigm for detecting endocrine toxicity of chemicals that are subject to regulation under the Food Quality Protection and the Safe Drinking Water Acts. In this study, we developed and evaluated a screening assay that could be employed to detect juvenoid-related endocrine-modulating activity in an invertebrate species. Juvenoid activity, anti-juvenoid activity, and juvenoid potentiator activity of chemicals was assessed using the water flea Daphnia magna. Male sex determination is under the regulatory control of juvenoid hormone, presumably methyl farnesoate, and this endpoint was used to detect juvenoid modulating activity of chemicals. Eighteen chemicals were evaluated for juvenoid agonist activity. Positive responses were detected with the juvenoid hormones methyl farnesoate and juvenile hormone III along with the insect growth regulating insecticides pyriproxyfen, fenoxycarb, and methoprene. Weak juvenoid activity also was detected with the cyclodiene insecticide dieldrin. Assays performed repetitively with compounds that gave either strong positive, weak positive, or negative response were 100% consistent indicating that the assay is not prone to false positive or negative responses. Five candidate chemicals were evaluated for anti-juvenoid activity and none registered positive. Four chemicals (all trans-retinoic acid, methoprene, kinoprene, bisphenol A) also were evaluated for their ability to potentiate the activity of methyl farnesoate. All registered positive. Results demonstrate that an in vivo assay with a crustacean species customarily employed in toxicity testing can be used to effectively screen chemicals for juvenoid-modulating activity.

Covert signal disruption: Anti‐ecdysteroidal activity of bisphenol a involves cross talk between signaling pathways

Bisphenol A is a key industrial chemical used in the manufacture of polycarbonate plastics and other products. Several recent reports ascribe toxicological properties to this compound that have been attributed to the disruption of endocrine-related processes. In the present study, the toxicity of bisphenol A was definitively characterized in the water flea (Daphnia magna) in an effort to discern whether this compound may elicit endocrine toxicity in an invertebrate species and to establish the mechanism by which this toxicity is elicited. The ability of bisphenol A to interfere with two ecdysteroid-dependent physiological processes--molting and embryonic development--was evaluated. Bisphenol A elicited antiecdysteroidal activity as indicated by its prolongation of the intermolt period and interference with embryonic development. This apparent antiecdysteroidal activity was not due to reduced availability of endogenous ecdysteroid nor due to ecdysteroid-receptor antagonism. The ability of bisphenol A to elicit antiecdysteroidal activity by functioning as a juvenoid hormone was next evaluated. Bisphenol A, alone, did not elicit juvenoid activity. However, bisphenol A did enhance the activity of the crustacean juvenoid hormone methyl farnesoate. A definitive assessment of the effects of bisphenol A on the reproductive capacity of daphnids revealed a concentration-response relationship that extended at least one order of magnitude below exposure levels that were overtly toxic to the maternal organisms. These results demonstrate that bisphenol A is chronically toxic to daphnids, probably through its ability to interfere with ecdysteroid/juvenoid regulated processes. However, effects are elicited at levels that are not likely to pose environmental concern.

Growth inhibitory effect of juvenile hormone analogues on epimastigotes of Trypanosoma cruzi

Several compounds, structurally related to the insect growth regulator Fenoxycarb, exhibited interesting inhibition action to control proliferation of Trypanosoma cruzi, the parasite responsible for Chagas' disease. Some of these drugs were shown to be potent growth inhibitors of this parasite. All of these drugs had previously presented juvenoid activity on several non-related bug species such as Tenebrio molitor, Galleria mellonella, Dysdercus cingulatos, and Pyrrhocoris apterus.

Comparative Contact Activity and Residual Life of Juvenile Hormone Analogs Used for German Cockroach (Dictyoptera: Blattellidae) Control

The contact activity and residual life of fenoxycarb, hydroprene, and pyriproxyfen were evaluated against the German cockroach, Blattella germanica (L.). Clean out and maintenance rates were tested on 3 surface types (tempered masonite, unpainted plywood, and stainless steel), and each was aged for up to 4 mo in laboratory and greenhouse environments. Juvenoid activity was determined by evaluating 2 response variables: the percentage of juvenoid- affected adults and twisted-wing rating of adults. Aging period and juvenoid main effects had more influence on the results than the surface type, environment, or dilution rate. Aging accounted for 28 and 36.1% of the variation for percentage of affected adults and twisted-wing rating, respectively. Juvenoids accounted for 22.7 and 21.7% of the variation, respectively. Fenoxycarb was significantly more active than hydroprene and pyriproxyfen and caused higher percentages of affected adults and twisted-wing ratings. Juvenoids aged in the laboratory were significantly more active than those aged in the greenhouse for the 2 response variables. Juvenoid activity on stainless steel was significantly higher than on all the other surfaces. Overall juvenoid effects for all surfaces produced a high percentage of affected adults (92.5%) and twisted wing rating (4.0) at a 1-d aging period. In the laboratory, only fenoxycarb continued to produce severely affected adults (89-100%) and high twisted-wing ratings (4.6- 4.9) throughout the 4-mo residual aging period for the 3 surface types. Hydroprene residues on stainless steel began to exhibit degradation in the severity of wing twisting at the 30-d aging period, and the activity declined sharply at 60 d. Pyriproxyfen on stainless steel continued to produce severely affected adults (86-100%) and twisted-wing ratings (2.9-4.5) throughout the 4-mo aging period, but pyriproxyfen exhibited a noticeable decline in efficacy at the 60-d aging period on tempered masonite and unpainted plywood. Persistence of the 3 juvenoids was affected by the extreme thermal conditions of the greenhouse. Fenoxycarb persisted for up to 60 d without exhibiting a decline in efficacy with twisted-wing ratings ranging from 3.0 to 3.7 on various surfaces. Fenoxycarb activity declined sharply at the 90-d aging period. The activity of hydroprene and pyriproxyfen was reduced significantly at the 30-d aging period with the percentage of affected adults ranging from 44 to 80% and 35 to 60%, and twisted-wing ratings ranging from 0.5 to 1.5 and 0.5 to 1.2 on various surfaces, respectively. The 3 juvenoids did not cause significant ecdysial mortality at either application rate. At clean out, the percentage of mortality of 5th instars during molting to adults ranged from 2.6 to 8.1 and 0.0 to 6.1 on surfaces aged in the laboratory for 1 and 30 d, respectively. The percentages ranged from 0.0-8.6 and 0.0-4.8 on surfaces treated with juvenoids aged in the greenhouse. Juvenoids have short residual lives when applied on selected surfaces aged under extreme conditions.

A novel geminal diol as a highly specific and stable in vivo inhibitor of insect juvenile hormone esterase

Thio-containing and acetylenic trifluoromethyl ketones were potent inhibitors of insect juvenile hormone (JH) esterase with greater inhibitory activity than aliphatic and α,β-unsaturated homologs. Octylthio-1,1,1-trifluoropropan-2-one was the most potent inhibitor with the greatest equilibrium hydration constant in pure water. However, a keto/hydrate equilibrium was not necessary for JH esterase inhibition. The carbonyl tautomer of 1-octyl [1-(3,3,3-trifluoropropan-2,2- dihydroxy)] sulfone (OTPdOH-sulfone) was not detectable, and yet OTPdOH-sulfone was a potent in vitro inhibitor of JH esterase with an I50 of 1.2 nM. The mechanism of JH esterase inhibition by these compounds is discussed. OTPdOH-sulfone inhibited JH esterase with minimal activity toward insect 1-naphthyl acetate esterase and electric eel acetylcholinesterase. The inhibitor was also active in vivo, selective for JH esterase, and persistent for over 32 h. OTPdOH-sulfone when topically applied to larval and adult cabbage loopers, Trichoplusia ni, elicited juvenoid activity apparently because of the specific in vivo inhibition of JH metabolism. Arch. Insect Biochem. Physiol. 36:165–179, 1997. © 1997 Wiley-Liss, Inc.

ChemInform Abstract: Ozonolysis of Alkenes and Reactions of Polyfunctionalized Compounds. Part 47. Synthesis of Diethers of 2,6‐Dimethyl‐2(E)‐octene‐1,8‐diol Possessing Juvenoid Activity.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Field Evaluation of Nylar for Control of Cat Fleas (Siphonaptera: Pulicidae) in Home Yards

Procedures were developed to evaluate juvenoid insect growth regulators in home yards as part of an ongoing program to identify photostable insecticides for control of the cat flea, Ctenocephalides felis (Bouché). Nylar, an emulsifiable concentrate formulation of pyriproxyfen, was selected as the experimental insect growth regulator. Efficacy studies, yard survey, and pretreatment sampling techniques are described. Soil samples collected from the yards at intervals after treatment were taken to the laboratory, infested with flea larvae, and tested for juvenoid activity. Results indicated that Nylar applied at a concentration of 32 mg/m2 in 0.82 liter of water/m2 (20 gal/1,000 ft2) prevented development of approximately 80% of the fleas for a period of 3 wk.

ChemInform Abstract: Preparation of Carbamate Derivatives of 2‐(4‐Hydroxybenzyl)‐1‐cyclohexanone with a Juvenoid Activity.

AbstractThe carbamates (IIa), (IIb), (II) (R′: ‐ OH"; R2: ‐ H) and (II) (R′: ‐ OHeq; R2: ‐ H) were prepared, the latter by NaBH4 reduction of (IIa) in MeOH as a racemic mixture, which is separable by column chromatography on silica gel (yields 43% each).

Preparation of carbamate derivatives of 2-(4-hydroxybenzyl)-1-cyclohexanone with a juvenoid activity

The synthesis of four carbamate derivatives of 2-(4-hydroxybenzyl)-1-cyclohexanone displaying a juvenilizing effect in insects is described. The substances prepared have a greater stability and activity than their carba-analogues prepared earlier.