Nectar, the main floral reward for pollinators, varies greatly in composition and concentration. The assumption that nectar quality is equivalent to its sugar (energy) concentration is too simple. Diverse non-sugar components, especially amino acids and secondary metabolites, play various roles in nutrition and health of pollinators. Many nectar compounds have indirect effects by altering the foraging behaviour of pollinators or protecting them from disease. This review also emphasizes the water component of nectar, often ignored because of evaporative losses and difficulties in sampling small nectar volumes. Nectar properties vary with environmental factors, pollinator visits and microbial contamination. Pollination mutualisms depend on the ability of insect and vertebrate pollinators to cope with and benefit from the variation and diversity in nectar chemistry. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.

Makaleyi görüntüle

Diabetes mellitus is one of the major health problems in the world, the incidence and associated mortality are increasing. Inadequate regulation of the blood sugar imposes serious consequences for health. Conventional antidiabetic drugs are effective, however, also with unavoidable side effects. On the other hand, medicinal plants may act as an alternative source of antidiabetic agents. Examples of medicinal plants with antidiabetic potential are described, with focuses on preclinical and clinical studies. The beneficial potential of each plant matrix is given by the combined and concerted action of their profile of biologically active compounds.

Makaleyi görüntüle

Aloe genus plants, distributed in Old World, are widely known and have been used for centuries as topical and oral therapeutic agents due to their health, beauty, medicinal, and skin care properties. Among the well-investigated Aloe species are A. arborescens , A. barbadensis , A. ferox , and A. vera . Today, they account among the most economically important medicinal plants and are commonly used in primary health treatment, where they play a pivotal role in the treatment of various types of diseases via the modulation of biochemical and molecular pathways, besides being a rich source of valuable phytochemicals. In the present review, we summarized the recent advances in botany, phytochemical composition, ethnobotanical uses, food preservation, and the preclinical and clinical efficacy of Aloe plants. These data will be helpful to provide future directions for the industrial and medicinal use of Aloe plants.

Makaleyi görüntüle

Ethnopharmacological relevance Bapedi phytomedicine employ a range of plant species to treat diabetes mellitus (DM). Existing literature partially support the use of certain species for this purpose. Aim of the study To report on Bapedi medicinal plants employed to treat DM. Materials and methods A semi-structured questionnaire was employed to conduct a survey on medicinal plants used by Bapedi traditional healers in their DM management protocol. Fifty-two traditional healers from 16 municipalities, covering three districts, were interviewed during the first half of 2011. Results A total of 24 plant species belonging to 20 families, mostly from the Asteraceae (13%), Cucurbitaceae and Sapotaceae (8%), were used to treat diabetes mellitus. Plant parts mostly preferred were roots and leaves. A decoction of these is most commonly used to make extracts, which are then taken orally for a period of one week. Mimusops zeyheri (29%), Helichrysum caespititium (25%), Plumeria obtusa (21%), Aloe marlothii subsp. marlothii, Hypoxis iridifolia and Moringa oleifera (17% each), were repeatedly mentioned by the traditional healers as most used for the management of diabetes mellitus in the study area. Plumeria obtusa and Momordica balsamina are exclusively used to treat diabetes mellitus, and only in the Sekhukhune District. Conclusion It is concluded that Bapedi traditional healers do have a basic understanding of the causes and remedial action required in the treatment of diabetes mellitus.

Makaleyi görüntüle

Background The nuclear DNA amount in an unreplicated haploid chromosome complement (1C-value) is a key diversity character with many uses. Angiosperm C-values have been listed for reference purposes since 1976, and pooled in an electronic database since 1997 (http://www.kew.org/cval/homepage). Such lists are cited frequently and provide data for many comparative studies. The last compilation was published in 2000, so a further supplementary list is timely to monitor progress against targets set at the first plant genome size workshop in 1997 and to facilitate new goal setting. Scope The present work lists DNA C-values for 804 species including first values for 628 species from 88 original sources, not included in any previous compilation, plus additional values for 176 species included in a previous compilation. Conclusions 1998-2002 saw striking progress in our knowledge of angiosperm C-values. At least 1700 first values for species were measured (the most in any five-year period) and familial representation rose from 30 % to 50 %. The loss of many densitometers used to measure DNA C-values proved less serious than feared, owing to the development of relatively inexpensive flow cytometers and computer-based image analysis systems. New uses of the term genome (e.g. in 'complete' genome sequencing) can cause confusion. The Arabidopsis Genome Initiative C-value for Arabidopsis thaliana (125 Mb) was a gross underestimate, and an exact C-value based on genome sequencing alone is unlikely to be obtained soon for any angiosperm. Lack of this expected benchmark poses a quandary as to what to use as the basal calibration standard for angiosperms. The next decade offers exciting prospects for angiosperm genome size research. The database (http://www.kew.org/cval/homepage) should become sufficiently representative of the global flora to answer most questions without needing new estimations. DNA amount variation will remain a key interest as an integrated strand of holistic genomics.

Makaleyi görüntüle