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1.
Betula platyphylla var. japonica (Betulaceae) has been used traditionally in Asian countries for the treatment of inflammatory diseases. A recent study has reported a phenolic compound, platyphylloside from B. platyphylla, that shows inhibition on adipocyte differentiation and induces lipolysis in 3T3-L1 cells. Based on this finding, we conducted phytochemical analysis of the EtOH extract of the bark of B. platyphylla var. japonica, which resulted in the isolation of phenolic glycosides (14). Treatment of the isolated compounds (14) during adipocyte differentiation of 3T3-L1 mouse adipocytes resulted in dose-dependent inhibition of adipogenesis. In mature adipocytes, arylbutanoid glycosides (24) induced lipolysis related genes HSL and ATGL, whereas catechin glycoside (1) had no effect. Additionally, arylbutanoid glycosides (24) also induced GLUT4 and adiponectin mRNA expression, indicating improvement in insulin signaling. This suggests that the isolates from B. platyphylla var. japonica exert benefial effects in regulation of adipocyte differentiation as well as adipocyte metabolism.  相似文献   

2.
Reinterpreting the State of Fisheries and their Management   总被引:1,自引:0,他引:1  
Ray Hilborn 《Ecosystems》2007,10(8):1362-1369
Abstract A series of recent high-profile papers in Science and Nature have led readers to believe that most fisheries worldwide are overexploited and that current fisheries management practices have universally failed. In reality, current fisheries management is working well to achieve the legislated objective of MSY in some countries but is failing in others. Here, I present three interpretations about the status of fisheries management that are widely accepted and for each consider an alternative interpretation of the data. I propose that, rather than abandoning current approaches to fisheries management, we should expand the use of the management tools used in fisheries that currently achieve biological and economic sustainability.  相似文献   

3.

Background  

Polypodium hydriforme is a parasite with an unusual life cycle and peculiar morphology, both of which have made its systematic position uncertain. Polypodium has traditionally been considered a cnidarian because it possesses nematocysts, the stinging structures characteristic of this phylum. However, recent molecular phylogenetic studies using 18S rDNA sequence data have challenged this interpretation, and have shown that Polypodium is a close relative to myxozoans and together they share a closer affinity to bilaterians than cnidarians. Due to the variable rates of 18S rDNA sequences, these results have been suggested to be an artifact of long-branch attraction (LBA). A recent study, using multiple protein coding markers, shows that the myxozoan Buddenbrockia, is nested within cnidarians. Polypodium was not included in this study. To further investigate the phylogenetic placement of Polypodium, we have performed phylogenetic analyses of metazoans with 18S and partial 28S rDNA sequences in a large dataset that includes Polypodium and a comprehensive sampling of cnidarian taxa.  相似文献   

4.
Trattinnickia is closely related toDacryodes and is transferred to the tribe Canarieae. Additional characters are proposed to supplement the weak characters that traditionally have been used to separateCrepidospermum andTetragastris fromProtium. The assumed “intermediate” genusParaprotium is shown to be an unnatural assemblage and is here merged withProtium. This revised concept of generic limits in the Neotropical Protieae and Canarieae leads to the following new combinations:Tetragastris occhionii (Rizzini) Daly,Protium pilosum (Cuatrec.) Daly,Protium nitidifolium (Cuatrec.) Daly,Protium vestitum (Cuatrec.) Daly, andDacryodes cuspidata (Cuatrec.) Daly. A key to the Neotropical genera of Burseraceae is provided.  相似文献   

5.
Tolmiea diplomenziesii, the diploid entity traditionally treated within a broadly circumscribed Tolmiea menziesii, is here formally described. Evidence is provided that this new species represents the diploid sister lineage to T., menziesii, which is re-circumscribed to include only autotetraploid plants. The diploid and autotetraploid entities are compared, and serve as an example of the level of taxonomic evidence for specific status that we consider appropriate for recognition of a cytological entity as a distinct species.  相似文献   

6.
7.
In the course of a phylogenetic analysis and systematic revision ofCharianthus, it was discovered thatC. purpureus, as traditionally circumscribed, is polyphyletic, consisting of three morphologically diagnosable entities. Thus two new species,Charianthus dominicensis andC. grenadensis, are described and illustrated. Each is endemic to the Lesser Antillean island for which it is named—Dominica and Grenada, respectively.Charianthus, the only vascular plant genus endemic to the Lesser Antilles, comprises six species of nectariferous, hummingbird-pollinated shrubs and small trees.  相似文献   

8.
This study used pollen morphology to address taxonomic controversies related to several species belonging to subgenus Hebeclada of the genus Polygala (Polygalaceae). According to the last traditionally accepted revision of this subgenus, it comprises 40 species. Nevertheless, a recent taxonomic treatment applying more comprehensive criteria reduced this number to only nine species. Our work focused on 15 traditionally accepted species that occur in Brazil, fourteen of which have been considered as only six species in this recent taxonomic study. Pollen grains from floral buds at pre‐anthesis were collected from herbarium specimens and analysed using both visible light and scanning electron microscopy. Most of the traditionally accepted species were distinguished by different combinations of several pollen‐related features, in particular colpi number (13 or 15), pollen size and shape, and endoaperture type (endocingulate or not) and arrangement (parallel or sinuous). The species accepted in the recent taxonomic treatment could not be discriminated by pollen characters. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 609–619.  相似文献   

9.
Taro (Colocasia esculenta [L.] Schott) Cultivation in Vertical Wet-Dry Environments: Farmers’ Techniques and Cultivar Diversity in Southwestern Ethiopia. Taro (Colocasia esculenta [L.] Schott) is a food crop that was domesticated in Asia and the Pacific region and is now grown in the humid tropics. Following its arrival in Africa in ancient times, it may have adapted to the drier environments. In this ethnographic study, I present a particular case of taro cultivation and uses by a group of farmers in the mountains of southwestern Ethiopia. There are 36 named cultivars of taro for which diversity is maintained through different cultivation techniques and culinary practices in wet and dry environments that vary in elevation. Because taro in dry lowland environments has recently been replaced by the introduction of new crops, it is possible that the drought-tolerant eddoe-type cultivars, which are traditionally dominant in Africa, are now in danger of disappearing.  相似文献   

10.
Abstract

Rhamnus lojaconoi, a new endemic species of Sicily. – The new species Rhamnus lojaconoi, occurring in the mediterranean-temperate forest of the Madonie (Northern Sicily) and probably a relict element connected with R. glandulosa Ait., endemic on the Atlantic Islands and living in similar habitats, is described. The taxonomic arrangement, the genetic interpretation and the ecology are also discussed.  相似文献   

11.
Purpose

Lactic acid bacteria (LAB) are traditionally employed in the food industry. LAB strains from goat milk may also present probiotic potential, and it is fundamental to study the safety and functionality aspects which are desirable for their use in food. The objective of this study was to verify the probiotic potential of lactic bacteria isolated from goat milk.

Methods

The presence of safety-related virulence factors (hemolytic activity, gelatinase production, coagulase, and sensitivity to antibiotics) as well as functionality (exopolysaccharide (EPS) production, proteolytic activity, autoaggregation, gas production, survival in the gastrointestinal tract, and antimicrobial activity against bacteria that impair oral health) were determined.

Result

The selected LAB strains are safe against the evaluated parameters and have characteristics of possible probiotic candidates. Especially L. plantarum (DF60Mi) and Lactococcus lactis (DF04Mi) have potential to be added to foods because they have better resistance to simulated gastrointestinal conditions. In addition, they are isolated with already proven antimicrobial activity against Listeria monocytogenes, an important food-borne pathogen. DF60Mi was able to produce EPS (exopolysaccharides). LS2 and DF4Mi strains, both Lactococcus lactis subsp. lactis, demonstrated antimicrobial activity against S. mutans ATCC 25175, a recurrent microorganism in oral pathologies, mainly caries.

Conclusion

This study provides subsidies for future exploration of the potentialities of these LAB strains for both the development of new functional foods and for application in oral health.

  相似文献   

12.
Abstract

Techniques available for assessing the tolerance of plants to heavy metal toxins are reviewed. All are based on physiological responses and range from long-term growth trials in metal-contaminated substrates, to rapid cytological tests. Problems associated with the ecophysiological interpretation of in vitro measurements of tolerance are considered. The implications of multiple tolerance, co-tolerance, constitutional tolerance, inducible tolerance and possible stimulatory effects of metals on plant responses are discussed.  相似文献   

13.
Purpose

Scientific information regarding the microbial content and functional aspects of fermented beverages traditionally produced in certain parts of Europe are scarce. However, such products are believed to have some health benefits and might contain functional bacterial strains, such as probiotics. The aim of the study was to identify such lactic acid bacteria strains isolated from water kefir and, for the first time, from braga, a Romanian fermented beverage made of cereals.

Methods

Lactic acid bacteria (LAB) were identified to species level based on (GTG)5-PCR fingerprinting and 16S rRNA gene sequencing. Selected strains were screened for their antibacterial activity and probiotic potential.

Results

Eight isolates belonging to seven Lactobacillus species were recovered from the two drinks. The identification of LAB involved in the fermentation of braga (Lactobacillus plantarum, Lactobacillus fermentum, and Lactobacillus delbrueckii) is firstly reported here. Five of the Lactobacillus isolates showed antibacterial activity against pathogenic bacteria, including Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Salmonella enterica. Moreover, most of them showed a good resistance to pH 2.5 and some survived at high concentrations of bile salts (up to 2%). Two L. plantarum isolates were able to inhibit all the indicator strains, and showed the best viability (about 70%) after a sequential treatment simulating the passage through the gastrointestinal tract.

Conclusion

Based on the results, the most promising candidates for designing new probiotic products are: L. plantarum BR9 from braga and L. plantarum CR1 from water kefir.

  相似文献   

14.
Ilex Vomitoria Ait. (Yaupon): A Native North American Source of a Caffeinated and Antioxidant-Rich Tea. Yaupon holly (Ilex vomitoria Ait.) is a caffeine-containing shrub native to the southeastern United States where its leaves and twigs were traditionally used to prepare a stimulating and healthful beverage by Amerindians and more recent colonists. For a variety of mostly socioeconomic and cultural reasons, widespread consumption of yaupon tea ceased by the late 19th century, but the species is widely used in ornamental horticulture. Given the environmental damage associated with other caffeine crops, we believe that disuse of this species is unfortunate, and we report on traits that consumers may consider valuable. We found that total foliar biomass, caffeine, and antioxidant production all increased with nitrogen fertilization in one common ornamental yaupon cultivar, ‘Nana.’ Increasing light availability was associated with increased antioxidant activity but not with the decreased caffeine production predicted by the carbon/nutrient balance hypothesis for secondary metabolite production. We also found the highest caffeine concentrations in another yaupon cultivar, ‘Pendula,’ but suggest that the wide range of chemical variation offered by wild-type yaupon populations renders them more suitable as sources for the development of high caffeine-producing varieties. The results of this study suggest that yaupon is a viable caffeine alternative for North Americans living within its range on the southeastern coastal plain.  相似文献   

15.
An extinct genus Abraracourcix n. gen. with A. curvivenatus n. sp. is described based on the specimen from the Lowermost Eocene Oise amber. The venation characters and possible hostplant relationships, as well as taxonomic position and biogeographical pattern of recent Pochazoides generic group are discussed.  相似文献   

16.
Abstract

Two chironomid flies, Ziadeus kamili n. gen., n. sp. and Paicheleria magnifica n. gen., n. sp., respectively attributed to the recent subfamilies Tanypodinae and Prodiamesinae, are described from the Early Cretaceous Lebanese amber. Although very old, this non-biting midge fauna was very diverse with no less than 11 genera and species. However, it was also strongly different from the recent faunas for the complete absence of the Chironominae, that is today the dominant subfamily. The development of the modern chironomid fauna occurred during the Late Cretaceous and/or the Early Paleogene, but when and how?  相似文献   

17.
Background: In Chinese folk medicine, Corni fructus (C. fructus) has traditionally been used to improve liver function, although the mechanism underlying its activity remains unclear. The aim of the present study was to evaluate the protective effects of wild C. fructus methanolic extract against acute alcoholic liver injury.

Methods: Alcohol was administered to mice for three consecutive days, either alone or in combination with C. fructus methanolic extract (50, 100, or 200?mg/kg body weight/d). Serum and liver tissue were collected from the animals and subjected to biochemical and histopathological analyses.

Results: C. fructus signi?cantly alleviated alcohol-induced liver injury by reducing serum alanine aminotransferase, aspartate aminotransferase, and thiobarbituric acid reactive species, inhibiting hydroxyl radicals (?OH), and increasing total superoxide dismutase, glutathione peroxidase, and glutathione in the liver (P?C. fructus treatment inhibited the expression and activity of cytochrome P450 2E1 (P?Conclusions: C. fructus could be a promising natural substance for ameliorating acute alcohol-induced oxidative stress and hepatic injury.  相似文献   

18.
A novel indole derivative (1) and three known compounds (24) were isolated from the fruiting bodies of Tricholoma flavovirens. Their structures were determined or identified by the interpretation of spectroscopic data. Compounds 1 and 2 promoted root growth of lettuce and inhibited hypocotyl growth at 1 μmol/paper. Compound 3 inhibited hypocotyl and root growth at 100 nmol/paper.  相似文献   

19.
New species of the genera Sapho and Epiaeschna are recorded in the Oligocene of Aix- en-Provence, Bouches-du-Rhône, France. Sapho legrandi n. sp. is the third fossil representative of this recent African genus and Epiaeschna pseudoheros n. sp. is the fifth fossil species of this recent North American genus. The fossil species Triaeschna gossi from the Eocene of England, Epacantha magnifica from the Late Oligocene of Kazakhstan, and Mediaeschna matutina from the Oligocene of China, are considered species of Epiaeschna and the three fossil genera Triaeschna Campion 1916, Mediaeschna Zhang 1989, and Epacantha Martynov 1929 are synonymized with Epiaeschna. The closely related genera Umma and Sapho inhabit warm humid forests of Western Africa. Their presence in two Oligocene deposits of France supports the hypothesis of a warm humid palaeoenvironment for Armissan (Aude, France), and Aix-en-Provence.  相似文献   

20.
Phylloclades are traditionally defined as flattened, determinate, leaf-like stems primarily on the basis of their axillary position. However, because the literature is replete with controversy over the morphological interpretation of these organs, a study of phylloclade development in comparison with leaf and stem development was undertaken in four closely related species of the Asparagaceae: Ruscus aculeatus, Danae racemosa, Semele androgyna and Asparagus densiflorus. Results reveal a continuum in phylloclade development from very leaf-like forms, such as those of Danae, via the more intermediate types of Ruscus, to the gradually more shootlike forms of Semele and Asparagus. This continuum results from a differential expression of stem (or shoot) and leaf characteristics in an axillary position. When stem (or shoot) and leaf features are combined, as in the fertile phylloclade of Ruscus, an intermediate organ is formed. Phylloclades are a form of evolutionary novelty that exemplifies the phenomenon of homoeosis, which is the transference of features from one organ to another. Developmentally, this means that leaf features are expressed by the axillary meristem.  相似文献   

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