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Ginkgo biloba is one of the oldest living tree species and its extracts or powdered leaves are one of the best selling herbal preparations. The main bioactive constituents are flavonoids and the terpene trilactones, ginkgolides and bilobalide, which are responsible for their pharmacological activity. However, there are many difficulties for ginkgo leaves supply and the chemical synthesis is far from of being applicable for commercial-scale production. G. biloba cell cultures have arisen as a useful alternative source of pharmacologically active terpene trilactones. This review sheds light on the chemistry and biosynthesis of terpene trilactones with the aim of increasing the production of these high value compounds by biotechnological approaches. Different biotechnological strategies to improve ginkgolides and bilobalide production will be discussed, including screening and selection of in vitro ginkgo cultures, cell differentiation levels of these cultures, optimization of culture conditions, feeding and elicitation strategies. Special attention will be paid in developing new methodologies to enhance ginkgo cell biomass and provide high amounts of these bioactive terpene trilactones using large-scale cell cultures.  相似文献   

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Three species of the parasitic isopod genus Minicopenaeon Bourdon, 1981 (Crustacea: Isopoda: Bopyridae) are reported from China, one new to science and two new records from mainland China. Minicopenaeon crosnieri (Bourdon, 1979) formerly known from Madagascar, the Philippines and Taiwan, is recorded from Zhejiang province. Minicopenaeon intermedium Bourdon, 1981 previously recorded from the Philippines and Japan, is recorded from China for the first time. The new species Minicopenaeon liuruiyui n. sp. is recorded from the East and South China Seas. As with other species of the genus, females of the new species have rudimentary coxal plates on the second pereomeres on the short side. The new species can be distinguished from other species by the presence of a widely open brood pouch, head with bilobate anterior edge and median concave groove, and male head with curved posterior margin of the pleon. A key to species of Minicopenaeon is provided and the subspecies M. intermedium curvatum Bourdon, 1981 is synonymised with M. intermedium Bourdon, 1981. Metapenaeopsis philippii (Bate, 1881) and M. coniger (Wood-Mason, 1891) are newly recorded as host species for bopyrids.  相似文献   

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A new tortoise beetle species, Cyrtonota abrili, is described from the Antioquia and Caldas departments in Colombia. New faunistic data are provided for 87 species, including 16 new additions to the country’s fauna. A checklist of the known 238 species of tortoise beetles recorded from Colombia is given.  相似文献   

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《Mycoscience》2014,55(4):260-267
Although bananas are economically important crops and many fungi are recorded from these plants, detailed data about the fungi are scarce, e.g. with respect to their distribution and morphology in the field and in culture. Three hyphomycetes (anamorphic Dothideomycetes) known as potential pathogens on leaves of Musa species were identified based on morphology and DNA sequences. For the first time, Ramichloridium biverticillatum and R. musae are recorded from Panama and R. biverticillatum and R. ducassei from Taiwan and new hosts. The fungi are described and illustrated in detail from observation in situ and compared to their known morphology in vitro, in order to clarify some deviating molecular and morphological data from different sources. An updated preliminary key to Ramichloridium species on banana leaves is provided.  相似文献   

6.
The genus Micatagla Argaman (Bradynobaenidae: Apterogyninae) is reviewed from Egypt, based on specimens collected from Wadi Allaqi (Aswan, Southern Egypt) and Kom Osheim (Fayoum) and those deposited in Egyptian insect collections as well as recorded data from the literature. A single species, Micatagla klugi (André), was previously recorded from Egypt. Micatagla allaqiensis sp. n., Micatagla ezzati sp. n. and Micatagla pseudorainerii sp. n. are described here. Micatagla antropovi Pagliano is also newly recorded from the Egyptian fauna. An illustrated key and a faunistic list comprising all Micatagla species recorded from Egypt are given.  相似文献   

7.
A leaf spot disease of melon caused by Alternaria alternata f.sp. cucurbitae was recorded for the first time in Crete. Necrotic flecks surrounded by chlorotic halos developed on the cotyledons and the leaves of the middle and the upper part of the plants; the flecks enlarged and coalesced to form lesions of 2 cm or more in diameter with brown fructifications of the pathogen on their surface. Severely affected cotyledons and leaves became chlorotic and died. Of 16 species from eight botanical families that were inoculated, only those of the Cucurbitaceae were susceptible. Of four isolates of A. alternata from tomato, sunflower, pear and cucumber, only the cucumber isolate was pathogenic to melon foliage.  相似文献   

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A new species of herbaceous bambusoid grass,Lithachne humilis, is described from Honduras and compared with the three other species known in the genus. As in many other grasses of this alliance, the leaves ofL. humilis exhibit so-called “sleep movements” at night. The diurnal and nocturnal positions of its leaves are compared to those ofStrephium distichophyllum. The leaves of the new species and of two of the others inLithachne hang down vertically at night, while those ofStrephium fold upward, which is the usual position assumed by leaves of bambusoid grasses during the night.  相似文献   

11.
Nine species of terrestrial isopods are reported for the Polynesian island of Rapa Nui (Easter Island) based upon museum materials and recent collections from field sampling. Most of these animals are non-native species, but two are new to science: Styloniscus manuvaka sp. n. and Hawaiioscia rapui sp. n. Of these, the former is believed to be a Polynesian endemic as it has been recorded from Rapa Iti, Austral Islands, while the latter is identified as a Rapa Nui island endemic. Both of these new species are considered ‘disturbance relicts’ and appear restricted to the cave environment on Rapa Nui. A short key to all the oniscidean species presently recorded from Rapa Nui is provided. We also offered conservation and management recommendations for the two new isopod species.  相似文献   

12.
This paper provides the first faunal checklist for Cicadidae (Hemiptera) from Panay, Philippines, comprising five species belonging to five genera. A new species, Platypleura lourensi sp. nov., and a new genus, Ggomapsalta gen. nov., are described. Dundubia vaginata (Fabricius, 1787) and Ggomapsalta vernalis (Distant, 1916) are newly recorded from Panay. Information on geographic distributions is provided.  相似文献   

13.
Ginkgo (Ginkgo biloba) is one of the oldest living tree species and has been widely used in traditional medicine. Leaf extracts of ginkgo, such as the standardized extract EGb761, have become one of the best-selling herbal products. However, no bioactive compound directed at plants has been reported in this species. Therefore, we investigated possible allelopathic activity and searched for allelopathically active substances in ginkgo leaves. An aqueous methanol leaf extract inhibited the growth of roots and shoots of garden cress (Lepidium sativum), lettuce (Lactuca sativa), timothy (Phleum pratense) and ryegrass (Lolium multiflorum) seedlings. The extract was purified by several chromatographic runs and an allelopathically active substance was isolated and identified by spectral analysis to be the novel compound 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid. The compound inhibited root and shoot growth of garden cress and timothy at concentrations greater than 3 μM. The activity of the compound was 10- to 52-fold that of nonanoic acid. These results suggest that 2-hydroxy-6-(10-hydroxypentadec-11-enyl)benzoic acid may contribute to the allelopathic effect caused by ginkgo leaf extract. The compound may also have potential as a template for the development of new plant control substances.  相似文献   

14.
Taxonomic revision of South American species ofGrindelia Willd. has revealed two new species from Uruguay:G. rupestris, an erect subshurb with crowded obovate denticulate leaves, subsessile heads, and pappus composed of numerous awns, andG. linearifolia, a prostrate shrublet with small entire linear leaves. Both species are described and illustrated. A key for the UruguayanGrindelia species is provided.  相似文献   

15.
Alternaria leaf blight is one of the most common diseases in watermelon worldwide. In Korea, however, the Alternaria species causing the watermelon leaf blight have not been investigated thoroughly. A total of 16 Alternaria isolates was recovered from diseased watermelon leaves with leaf blight symptoms, which were collected from 14 fields in Korea. Analysis of internal transcribed spacer (ITS) region, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and RNA polymerase II second largest subunit (RPB2) were not competent to differentiate the Alternaria isolates. On the contrary, analysis of amplicon size of the histone H3 (HIS3) gene successfully differentiated the isolates into three Alternaria subgroups, and further sequence analysis of them identified three Alternaria spp. Alternaria tenuissima, A. gaisen, and A. alternata. Representative Alternaria isolates from three species induced dark brown leaf spot lesions on detached watermelon leaves, indicating that A. tenuissima, A. gaisen, and A. alternata are all causal agents of Alternaria leaf blight. Our results indicate that the Alternaria species associated watermelon leaf blight in Korea is more complex than reported previously. This is the first report regarding the population structure of Alternaria species causing watermelon leaf blight in Korea.  相似文献   

16.
A new species of woody Apiaceae, Polemanniopsis namibensis B-E. Van Wyk, A. Burke & C. Mannheimer, is described. The species is allied to Polemanniopsis marlothii but differs in the much smaller habit of (up to 0.6 m vs 1.5–4 m in Polemanniopsis marlothii), the white or greyish colour of the twigs (brown in Polemanniopsis marlothii), the 3-foliolate leaves (predominantly 5-foliate in Polemanniopsis marlothii), the smaller inflorescences with persistent involucral bracts (caducous in Polemanniopsis marlothii) and anatomical details of the leaves. The species is endemic to Namibia and is known only from a localised area in the southern Namib desert near Lüderitz, where it is relatively common.  相似文献   

17.
《Journal of Asia》2019,22(3):941-946
The genus Antispila Hübner, [1825] is poorly recorded from China. Two new Antispila species, A. longcangensis, sp. nov. and A. emeishanensis, sp. nov. feeding on Hydrangeaceae, are described from Sichuan, China. The adult male and female, genitalia and venation of both species are illustrated. Diagnostic characters of these species are compared with other described Antispila species from China. DNA barcodes sequences of the two new species are also provided.  相似文献   

18.
《Journal of Asia》2021,24(4):1055-1065
In this revision of the subtribe Pemphredonina (Crabronidae: Pemphredoninae: Pemphredonini) from China, we reported several species present in respected subtribe, out of which one species is new to science Passaloecus frontirugatus Bashir and Ma, sp. nov., and six species are recorded for the first time from China, including Polemistus palawanensis Tsuneki, Diodontus insidiosus Spooner, Diodontus handlirschi Kohl, Diodontus tiemudzhin Tsuneki, Diodontus spinicerus Kazenas, and Diodontus kuroo Tsuneki. A key to genera and the species of Diodontus and Passaloecus from China is also provided. Distributional records from China of each genus are also given.  相似文献   

19.
A new species, Cheilosia richterae sp. n., is described in the nominotypical subgenus, being most closely related there to Ch. annulifemur Stackelberg, 1930. Two species, Ch. sootryeni Nielsen, 1970 and Ch. rufimana (Becker, 1984), are recorded from Russia for the first time. Ch. kuznetzovae Skufjin, 1977 is recorded for the first time from the Urals and western Siberia. The subgenus Nephocheila Barkalov, 2002 is synonymized with Nephomyia Matsumura, 1916. Figures of the male and female heads and the male genitalia are given for all the species.  相似文献   

20.
The Indian species of Dicopus Enock are reviewed and illustrated. Two species are described as new: D. kamrani sp. nov., D. obesus sp. nov. Dicopus noyesi Manickavasagam is recorded from Karnataka. A key to Indian species is provided.  相似文献   

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