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K. R. Chandrashekar - One of the best experts on this subject based on the ideXlab platform.

  • Larvicidal activities of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) extracts against Aedes albopictus Skuse and Anopheles stephensi Liston
    Parasitology Research, 2011
    Co-Authors: R. Shwetha, K. R. Chandrashekar
    Abstract:

    In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. The present study was undertaken to investigate the effect of Aril and kernel extracts of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) on larvae of Aedes albopictus Skuse and Anopheles stephensi Liston under laboratory conditions. The Aril was extracted with chloroform and ethanol; the kernel was extracted with ethanol and hexane. The extracts were tested against the 3rd–4th instar larvae collected from Bunder area, Mangalore, India, which is a well-known fishing harbour, where several mosquito-borne diseases were reported. All the graded concentrations (100, 200, 300, 400 and 500 ppm) showed significant larval mortality after 24 h of observation. Chloroform extracts of Aril showed 100% mortality against both larval forms of A. albopictus and A. stephensi at the concentration of 500 ppm. Among the extracts tested, chloroform extracts of Aril and ethanol extracts of kernel exhibited higher toxicity against both A. albopictus (LC_50, 141 ppm and 159 ppm; LC_90, 290 ppm and 342 ppm) and A. stephensi (LC_50, 160 ppm and 162 ppm; LC90, 445 ppm and 458 ppm). Hexane extracts of kernel exhibited least toxicity against A. albopictus (LC50, 239 ppm; LC_90, 484 ppm), whereas ethanol extracts of Aril showed the least toxicity against A. stephensi (LC_50, 290; LC_90, 498). A preliminary phytochemical assay revealed the presence of phenolics, tannins, steroids, terpenes, resins, and glycolipids in all the extracts. Alkaloids, flavonoids and saponins were absent. The lower LC_50 value of the chloroform extracts of K. attenuata Aril indicates its potentiality as a larvicide against A. albopictus and A. stephensi mosquito larvae.

  • larvicidal activities of knema attenuata hook f thomson warb myristicaceae extracts against aedes albopictus skuse and anopheles stephensi liston
    Parasitology Research, 2011
    Co-Authors: R. Shwetha, K. R. Chandrashekar
    Abstract:

    In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. The present study was undertaken to investigate the effect of Aril and kernel extracts of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) on larvae of Aedes albopictus Skuse and Anopheles stephensi Liston under laboratory conditions. The Aril was extracted with chloroform and ethanol; the kernel was extracted with ethanol and hexane. The extracts were tested against the 3rd–4th instar larvae collected from Bunder area, Mangalore, India, which is a well-known fishing harbour, where several mosquito-borne diseases were reported. All the graded concentrations (100, 200, 300, 400 and 500 ppm) showed significant larval mortality after 24 h of observation. Chloroform extracts of Aril showed 100% mortality against both larval forms of A. albopictus and A. stephensi at the concentration of 500 ppm. Among the extracts tested, chloroform extracts of Aril and ethanol extracts of kernel exhibited higher toxicity against both A. albopictus (LC50, 141 ppm and 159 ppm; LC90, 290 ppm and 342 ppm) and A. stephensi (LC50, 160 ppm and 162 ppm; LC90, 445 ppm and 458 ppm). Hexane extracts of kernel exhibited least toxicity against A. albopictus (LC50, 239 ppm; LC90, 484 ppm), whereas ethanol extracts of Aril showed the least toxicity against A. stephensi (LC50, 290; LC90, 498). A preliminary phytochemical assay revealed the presence of phenolics, tannins, steroids, terpenes, resins, and glycolipids in all the extracts. Alkaloids, flavonoids and saponins were absent. The lower LC50 value of the chloroform extracts of K. attenuata Aril indicates its potentiality as a larvicide against A. albopictus and A. stephensi mosquito larvae.

R. Shwetha - One of the best experts on this subject based on the ideXlab platform.

  • Larvicidal activities of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) extracts against Aedes albopictus Skuse and Anopheles stephensi Liston
    Parasitology Research, 2011
    Co-Authors: R. Shwetha, K. R. Chandrashekar
    Abstract:

    In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. The present study was undertaken to investigate the effect of Aril and kernel extracts of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) on larvae of Aedes albopictus Skuse and Anopheles stephensi Liston under laboratory conditions. The Aril was extracted with chloroform and ethanol; the kernel was extracted with ethanol and hexane. The extracts were tested against the 3rd–4th instar larvae collected from Bunder area, Mangalore, India, which is a well-known fishing harbour, where several mosquito-borne diseases were reported. All the graded concentrations (100, 200, 300, 400 and 500 ppm) showed significant larval mortality after 24 h of observation. Chloroform extracts of Aril showed 100% mortality against both larval forms of A. albopictus and A. stephensi at the concentration of 500 ppm. Among the extracts tested, chloroform extracts of Aril and ethanol extracts of kernel exhibited higher toxicity against both A. albopictus (LC_50, 141 ppm and 159 ppm; LC_90, 290 ppm and 342 ppm) and A. stephensi (LC_50, 160 ppm and 162 ppm; LC90, 445 ppm and 458 ppm). Hexane extracts of kernel exhibited least toxicity against A. albopictus (LC50, 239 ppm; LC_90, 484 ppm), whereas ethanol extracts of Aril showed the least toxicity against A. stephensi (LC_50, 290; LC_90, 498). A preliminary phytochemical assay revealed the presence of phenolics, tannins, steroids, terpenes, resins, and glycolipids in all the extracts. Alkaloids, flavonoids and saponins were absent. The lower LC_50 value of the chloroform extracts of K. attenuata Aril indicates its potentiality as a larvicide against A. albopictus and A. stephensi mosquito larvae.

  • larvicidal activities of knema attenuata hook f thomson warb myristicaceae extracts against aedes albopictus skuse and anopheles stephensi liston
    Parasitology Research, 2011
    Co-Authors: R. Shwetha, K. R. Chandrashekar
    Abstract:

    In recent years, uses of environment friendly and biodegradable natural insecticides of plant origin have received renewed attention as agents for vector control. The present study was undertaken to investigate the effect of Aril and kernel extracts of Knema attenuata (Hook. f. & Thomson) Warb. (Myristicaceae) on larvae of Aedes albopictus Skuse and Anopheles stephensi Liston under laboratory conditions. The Aril was extracted with chloroform and ethanol; the kernel was extracted with ethanol and hexane. The extracts were tested against the 3rd–4th instar larvae collected from Bunder area, Mangalore, India, which is a well-known fishing harbour, where several mosquito-borne diseases were reported. All the graded concentrations (100, 200, 300, 400 and 500 ppm) showed significant larval mortality after 24 h of observation. Chloroform extracts of Aril showed 100% mortality against both larval forms of A. albopictus and A. stephensi at the concentration of 500 ppm. Among the extracts tested, chloroform extracts of Aril and ethanol extracts of kernel exhibited higher toxicity against both A. albopictus (LC50, 141 ppm and 159 ppm; LC90, 290 ppm and 342 ppm) and A. stephensi (LC50, 160 ppm and 162 ppm; LC90, 445 ppm and 458 ppm). Hexane extracts of kernel exhibited least toxicity against A. albopictus (LC50, 239 ppm; LC90, 484 ppm), whereas ethanol extracts of Aril showed the least toxicity against A. stephensi (LC50, 290; LC90, 498). A preliminary phytochemical assay revealed the presence of phenolics, tannins, steroids, terpenes, resins, and glycolipids in all the extracts. Alkaloids, flavonoids and saponins were absent. The lower LC50 value of the chloroform extracts of K. attenuata Aril indicates its potentiality as a larvicide against A. albopictus and A. stephensi mosquito larvae.

Paula J. Rudall - One of the best experts on this subject based on the ideXlab platform.

  • Origin of the Taxaceae Aril : evolutionary implications of seed-cone teratologies in Pseudotaxus chienii
    Annals of botany, 2018
    Co-Authors: Veit Martin Dörken, Hubertus Nimsch, Paula J. Rudall
    Abstract:

    Background and Aims Fleshy structures that promote biotic dispersal by ingestion have evolved many times in seed plants. Within the yew family Taxaceae sensu lato (six genera, including Cephalotaxus), it remains controversial whether the characteristic fleshy structure surrounding the seed is interpreted as a novel outgrowth of the base of the ovule (i.e. an Aril) or a fleshy seed coat that is entirely derived from the integument (i.e. a sarcotesta). This paper presents a detailed study of both wild-type and teratological seed cones of Pseudotaxus chienii, including morphology, anatomy and ontogeny. Methods Wild-type and teratological seed cones were investigated with the classical paraffin technique and subsequent astrablue/safranin staining and scanning electron microscopy. Key Results The wild-type seed cone of Pseudotaxus possesses a fleshy white Aril that is cup-like and not entirely fused to the seed. In the teratological seed cones investigated, the Aril was bilobed and consisted of two free halves. In both wild-type and teratological cones, the Aril was initiated as two lateral primordia in a transverse plane, but in wild-type cones the two primordia became extended into a ring primordium, which grew apically, leading to the cup-like shape. The teratological seed cones lacked a ring primordium and the two lateral Aril lobes remained free throughout their entire ontogeny, alternating with the scale-like leaves inserted below them on the same branch; in some cases, these leaves also became fleshy. Conclusions Based on the ontogeny and arrangement of the two fleshy Aril lobes in the teratological seed cones of Pseudotaxus, we suggest that the typical Aril of Taxaceae could be readily interpreted as a fused pair of strongly swollen leaves rather than a modified integument. Our investigations of the cup-like Aril of Pseudotaxus demonstrate a similarity not only with other Taxaceae but also with relatively distantly related conifers such as Phyllocladus (Podocarpaceae).

Veit Martin Dörken - One of the best experts on this subject based on the ideXlab platform.

  • Origin of the Taxaceae Aril : evolutionary implications of seed-cone teratologies in Pseudotaxus chienii
    Annals of botany, 2018
    Co-Authors: Veit Martin Dörken, Hubertus Nimsch, Paula J. Rudall
    Abstract:

    Background and Aims Fleshy structures that promote biotic dispersal by ingestion have evolved many times in seed plants. Within the yew family Taxaceae sensu lato (six genera, including Cephalotaxus), it remains controversial whether the characteristic fleshy structure surrounding the seed is interpreted as a novel outgrowth of the base of the ovule (i.e. an Aril) or a fleshy seed coat that is entirely derived from the integument (i.e. a sarcotesta). This paper presents a detailed study of both wild-type and teratological seed cones of Pseudotaxus chienii, including morphology, anatomy and ontogeny. Methods Wild-type and teratological seed cones were investigated with the classical paraffin technique and subsequent astrablue/safranin staining and scanning electron microscopy. Key Results The wild-type seed cone of Pseudotaxus possesses a fleshy white Aril that is cup-like and not entirely fused to the seed. In the teratological seed cones investigated, the Aril was bilobed and consisted of two free halves. In both wild-type and teratological cones, the Aril was initiated as two lateral primordia in a transverse plane, but in wild-type cones the two primordia became extended into a ring primordium, which grew apically, leading to the cup-like shape. The teratological seed cones lacked a ring primordium and the two lateral Aril lobes remained free throughout their entire ontogeny, alternating with the scale-like leaves inserted below them on the same branch; in some cases, these leaves also became fleshy. Conclusions Based on the ontogeny and arrangement of the two fleshy Aril lobes in the teratological seed cones of Pseudotaxus, we suggest that the typical Aril of Taxaceae could be readily interpreted as a fused pair of strongly swollen leaves rather than a modified integument. Our investigations of the cup-like Aril of Pseudotaxus demonstrate a similarity not only with other Taxaceae but also with relatively distantly related conifers such as Phyllocladus (Podocarpaceae).

Jiang Xuepin - One of the best experts on this subject based on the ideXlab platform.

  • Review on Essential Extractive of Torreya Grandis Aril
    Journal of Food Science and Technology-mysore, 2014
    Co-Authors: Jiang Xuepin
    Abstract:

    The essential extractive of torreya grandis Aril has a lot of bioactivities,such as anti-oxidation,anti-tumor,and bacteriostatic action,which could be used in food and cosmetics. The resource of torreya grandis Aril is rich but few studies focused on it. The chemical composition of torreya grandis Aril and extraction methods,biological activities,and application prospects of essential oil were summarized.