Objective:To study the morphology,biochemistry and bioactivity of the epidermal glands of the glandular morphotype of Christella parasitica(C.parasitica)(L.) H.Lev.Methods: Morphological studies on epidermal glands we...Objective:To study the morphology,biochemistry and bioactivity of the epidermal glands of the glandular morphotype of Christella parasitica(C.parasitica)(L.) H.Lev.Methods: Morphological studies on epidermal glands were earned out by using light microscope and scanning electron microscope.To prepare the extract,the shade-dried fronds of glandular morphotype were soaked in acetone.For antibacterial studies paper disc method was followed by using various pathogenic bacteria.Results:Detailed micromorphological,phytochemical and bioactivity studies on a medicinal fern C.parasitica(L.) H.Lev.showed its inlraspecific variation in antibacterial activity.The presence or absence of the epidermal glands was the key factor for antibacterial activity in the morphovariants of this species.The epidermal glands were orange-coloured,stalked and elongated ones of about 84.2μm×45μm,and distributed on the undersurface of cosla,coslules and veins in croziers,young and mature leaves.Frequency of glands varied from 15/cm on costa in mature leaves to 140/cm on costules in croziers.The acetone extract of the glands showed antibacterial activities and also toxic effect against mosquito larvae and tadpoles of frog.Preliminary phytochemical analysis and HPLC studies of the gland extract showed the presence of various kinds of terpenoids,alkaloids,tannins,saponins and flavonoids in it.Conclusions:The present study shows that epidermal glands of the glandular morphotype of C. parasitica(L.) H.Lev.have several bioactive compounds and such rare moiphovariant should be conserved in nature.The next step is to isolate the pure compounds and to screen the bioactivity of individual compounds of the epidermal glands.展开更多
The wasps of the genus Polistes have been considered the key to understanding the evolution of social behavior in Hymenoptera. Several studies have shown that the development of organized insect societies was accompan...The wasps of the genus Polistes have been considered the key to understanding the evolution of social behavior in Hymenoptera. Several studies have shown that the development of organized insect societies was accompanied by the evolution of structures like exocrine glands, which became specialized to perform specific functions. This article investigates the ultrastructural and cytochemical features of the hypopharyngeal glands of Polistes versicolor. These glands have been studied in depth in social bees, where they occur only in nurses and produce the royal jelly. Our results＇ revealed that these glands basically did not vary among individuals or between sexes. They are constituted by spherical cells, each with a large nucleus and well-developed rough endoplasmic reticulum. Secretion vesicles are abundant, but lipid droplets were not observed, indicating that these glands may not have a role in pheromone synthesis. Acid phosphatase was detected in lysosomes, and also flee in the cytosol, but did not seem to be related with cell death. Thus, our results suggest that the hypopharyngeal glands ofP. versicolor may not have a specialized social role, but could produce digestive enzymes.展开更多
Females of the solitary parasitoid Diadromus collaris （Insecta： Hymenoptera： Ichneumonidae） lay eggs in the pupae of Plutella xylostella （Lepidoptera： Plutellidae）, and the venom is synchronously injected into ...Females of the solitary parasitoid Diadromus collaris （Insecta： Hymenoptera： Ichneumonidae） lay eggs in the pupae of Plutella xylostella （Lepidoptera： Plutellidae）, and the venom is synchronously injected into hosts. The venom apparatus consists of two glandular tubules terminating in a common reservoir, A ductule connects the reservoir with the sting apparatus, by which the reservoir content enters the latter. Secretory units line the two glandular tubules. All secretory cells belong to dermal gland type Ⅲ. Dermal gland cells in glandular tubules are more abundant and developed than those in the reservoir. There are extensive rough endoplasmic reticulum and electrondense vesicles, and the microvilli are well developed. By the cuticle-lined central funnel secretion products of secretory units reach the reservoir. Moreover, the secretory apparatus undergoes age-related changes. The secretory units in the venom gland are better developed and more vigorous 7 days after eclosion than those 1 day after eclosion; autolytic processes occur 15 days after eclosion, and the tissue of the reservoir is more prostrate 15 day after eclosion than those 1 day after eclosion. The ovipostion peak of this parasitoid, about 3-7 days after eclosion, corresponds with the period when the venom gland is highly developed in the life span of the wasp.展开更多
文摘Objective:To study the morphology,biochemistry and bioactivity of the epidermal glands of the glandular morphotype of Christella parasitica(C.parasitica)(L.) H.Lev.Methods: Morphological studies on epidermal glands were earned out by using light microscope and scanning electron microscope.To prepare the extract,the shade-dried fronds of glandular morphotype were soaked in acetone.For antibacterial studies paper disc method was followed by using various pathogenic bacteria.Results:Detailed micromorphological,phytochemical and bioactivity studies on a medicinal fern C.parasitica(L.) H.Lev.showed its inlraspecific variation in antibacterial activity.The presence or absence of the epidermal glands was the key factor for antibacterial activity in the morphovariants of this species.The epidermal glands were orange-coloured,stalked and elongated ones of about 84.2μm×45μm,and distributed on the undersurface of cosla,coslules and veins in croziers,young and mature leaves.Frequency of glands varied from 15/cm on costa in mature leaves to 140/cm on costules in croziers.The acetone extract of the glands showed antibacterial activities and also toxic effect against mosquito larvae and tadpoles of frog.Preliminary phytochemical analysis and HPLC studies of the gland extract showed the presence of various kinds of terpenoids,alkaloids,tannins,saponins and flavonoids in it.Conclusions:The present study shows that epidermal glands of the glandular morphotype of C. parasitica(L.) H.Lev.have several bioactive compounds and such rare moiphovariant should be conserved in nature.The next step is to isolate the pure compounds and to screen the bioactivity of individual compounds of the epidermal glands.
文摘The wasps of the genus Polistes have been considered the key to understanding the evolution of social behavior in Hymenoptera. Several studies have shown that the development of organized insect societies was accompanied by the evolution of structures like exocrine glands, which became specialized to perform specific functions. This article investigates the ultrastructural and cytochemical features of the hypopharyngeal glands of Polistes versicolor. These glands have been studied in depth in social bees, where they occur only in nurses and produce the royal jelly. Our results＇ revealed that these glands basically did not vary among individuals or between sexes. They are constituted by spherical cells, each with a large nucleus and well-developed rough endoplasmic reticulum. Secretion vesicles are abundant, but lipid droplets were not observed, indicating that these glands may not have a role in pheromone synthesis. Acid phosphatase was detected in lysosomes, and also flee in the cytosol, but did not seem to be related with cell death. Thus, our results suggest that the hypopharyngeal glands ofP. versicolor may not have a specialized social role, but could produce digestive enzymes.
基金We are grateful to Professor Hong Jian and Mrs Yuexian Fang （Zhejiang University, Hangzhou） for their help with transmission electron microscopy. Funding for this study was provided jointly by National Natural Science Foundation of China （NSFC number： 30370959） and Program for New Century Excellent Talents in University （NCET-04- 0521）.
文摘Females of the solitary parasitoid Diadromus collaris （Insecta： Hymenoptera： Ichneumonidae） lay eggs in the pupae of Plutella xylostella （Lepidoptera： Plutellidae）, and the venom is synchronously injected into hosts. The venom apparatus consists of two glandular tubules terminating in a common reservoir, A ductule connects the reservoir with the sting apparatus, by which the reservoir content enters the latter. Secretory units line the two glandular tubules. All secretory cells belong to dermal gland type Ⅲ. Dermal gland cells in glandular tubules are more abundant and developed than those in the reservoir. There are extensive rough endoplasmic reticulum and electrondense vesicles, and the microvilli are well developed. By the cuticle-lined central funnel secretion products of secretory units reach the reservoir. Moreover, the secretory apparatus undergoes age-related changes. The secretory units in the venom gland are better developed and more vigorous 7 days after eclosion than those 1 day after eclosion; autolytic processes occur 15 days after eclosion, and the tissue of the reservoir is more prostrate 15 day after eclosion than those 1 day after eclosion. The ovipostion peak of this parasitoid, about 3-7 days after eclosion, corresponds with the period when the venom gland is highly developed in the life span of the wasp.
