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1.
Adansonia digitata L. (Malvaceae) is a majestic tree revered in Africa for its medicinal and nutritional value. The plant parts are used to treat various ailments such as diarrhoea, malaria and microbial infections. It is reported that it is an excellent anti-oxidant due to the vitamin C content which is seven to ten times higher than the vitamin C content of oranges. Baobab has numerous biological properties including antimicrobial, antiviral, anti-oxidant and anti-inflammatory activities amongst others. Phytochemical investigation revealed the presence of flavonoids, phytosterols, amino acids, fatty acids, vitamins and minerals. The seeds are a source of significant quantities of lysine, thiamine, calcium and iron. Baobab is an important commodity which is integral to the livelihood of rural communities. In addition, the global demand for baobab raw material (e.g. seed oil, fruit pulp) by the food and beverage, nutraceutical and cosmetic industries has increased dramatically in recent years thereby increasing the commercial value and importance of this coveted African tree. In the past few years, there has been an increased demand for non-timber forest products (NTFPs), specifically baobab seed oil for inclusion in cosmetic formulations due to its high fatty acid composition. This review summarises the botanical aspects, ethnobotany, phytochemistry, biological properties and most importantly the nutritional value and commercial importance of baobab products.  相似文献   

2.
产业生态学最新研究进展及趋势展望   总被引:9,自引:1,他引:9  
袁增伟  毕军 《生态学报》2006,26(8):2709-2715
传统末端治理方式的弊端和清洁生产技术的局限性促使人们探求新的污染防治模式,生态学尤其是仿生学的发展激发了人们仿照自然生态系统来改造人类生产系统的想法,基于这种背景,产业生态学应运而生。分析了产业生态学诞生的背景及其形成过程,并全面系统论述了产业生态学领域的国内外进展,识别了目前我国该领域面临的问题与困境,并给出了对策建议。在此基础上,文章从学科发展的角度对产业生态学的发展趋势和前景作了展望。  相似文献   

3.
All dihydropyridines, except nifedipine, have at least one chiral center, and their pharmacokinetics and clinical effects differ from one enantiomer to another. Chiral separation methods for dihydropyridines using chromatographic techniques are discussed. The stereoselective pharmacokinetics of dihydropyridine calcium antagonists were reviewed in detail in 1995. The present review article updates the methods for the stereoselective determination of dihydropyridines using chromatographic techniques and summarizes the pharmacokinetics of the dihydropyridines, including the newest drugs under development.  相似文献   

4.
Massive production of keratinaceous byproducts in the form of agricultural and industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This review summarizes the potential utility of some bacterial and fungal species for the production of keratinase using a variety of keratinaceous wastes as growth substrates. The application of microbial keratinases in waste management; animal feed, detergent, and fertilizer manufacturing; and leather, cosmetic, and pharmaceutical industries is also abridged in this review.  相似文献   

5.
6.
Ochratoxin A (OTA) can be detected worldwide from various food and feed sources. It is produced byPenicillium nordicum andP. verrucosum as well as by variousAspergillus species, withA. ochraceus andA. carbonarius as the predominant producers. Various pairs of PCR primers based on AFLP, RAPD as well as primers specific to ribosomal RNA and genes coding for calmodulin and OTA biosynthetic pathway components were recently developed to detect and identify OTA producers in conventional and real-time PCR assays. Application of such assays in contaminated samples was demonstrated only in few cases. The current review gives an updated overview over the methods at hand.  相似文献   

7.
The aim of this study was to characterize several aspects of species of the genus Dietzia, such as current taxonomic placement, morphological and growth characteristics, biochemical reactions, cellular lipid and fatty acid composition, the amino acids and sugars of whole-cell hydrolysates and the respiratory quinone system, and genomic guanine and cytosine (G + C) content. The species chosen for study were D. aerolata, D. alimentaria, D. aurantiaca, D. cerdiciphylli, D. cinnamea, D. kunjamensis, D. lutea, D. maris, D. natronolimnaea, D. papillomatosis, D. psychralcaliphila, D. schimae, and D. timorensis. The colony morphology study revealed that the colonies were small, smooth, circular and convex. Nitrate reduction, H2S production, hydrolysis of urea, starch, and Tween 80, and the Voges–Proskauer and methyl red tests were performed for biochemical differentiation of the various Dietzia strains. Optimum growth temperature and pH for the different strains were 25–30 °C and 7–8, respectively. Among the strains studied, D. timorensis ID05-A0528T had the lowest tolerance level to NaCl (7 %). This strain was also able to utilize a wide range of compounds as the sole carbon source. Short-chain mycolic acids were present in these bacteria. The cell wall contained meso-diaminopimelic acid, arabinose, and galactose; the glycan moiety of the cell wall contained acetyl residues. The major menaquinone was MK-8 (H2). The G + C contents of the DNA ranged from 64.7 (D. alimentaria 72T) to 73 mol?% (D. maris DSM 43672T). The most important phospholipids in these strains were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, and phosphatidylethanolamine.  相似文献   

8.
Molecular Biology Reports - Flavonoids are members of polyphenolic compounds, which are naturally presented in fruits, vegetables, and some medicinal plants. Traditionally, the root of Scutellaria...  相似文献   

9.
Apoptosis - Chemoresistance of cancer cells is a major problem in treating cancer. Knowledge of how cancer cells may die or resist cancer drugs is critical to providing certain strategies to...  相似文献   

10.
Metallic antiquities and works of art are no exception to the phenomenon of microbial corrosion. Thus, all those which are buried, sunk or poorly conserved are susceptible to microbial corrosion. Although the last few decades have seen a marked development in the study of microbial corrosion of metals in industrial use, the same cannot be said for metallic antiquities and works of art. This work reviews the practical cases published, historical materials affected, and the micro-organisms involved and their mechanisms of action. Despite the great social importance of recovering these metallic cultural properties, and conserving them in a good state, there is a lack of documentation and of research groups dedicated to their study. The bringing together of researchers in works of art, microbiology and corrosion in metallic materials is shown to be necessary.  相似文献   

11.
This paper highlights the methods and parameters used to define and design a reference scenario to be compared with an industrial symbiosis (IS) scenario using the life cycle assessment (LCA) methodology. To this end, a critical review was conducted of 26 peer‐reviewed papers using LCA in the field of IS. The analysis focuses on the definition and design of reference scenarios through five cross‐analyses to determine correlations between the type and the number of reference scenarios and the type of IS scenarios studied and also some LCA characteristics such as the functional unit, the type of data used, and the use of sensitivity analysis. Results show that the definition of reference scenarios depends mainly on the type of IS scenario considered. For a current IS developed at an industrial scale, the suitable reference scenario is mainly a hypothetical nonsymbiotic reference scenario. For a prospective IS, the suitable reference scenario is mainly a current nonsymbiotic reference scenario. Due to this critical review, the problem of variability of reference scenarios emerges. To resolve it, the authors analyze different reference scenarios or use sensitivity analysis. What is more, territorial aspects are rarely taken into account in the design of reference scenarios. It is clearly a gap for LCA of IS because of the influence of territorial factors. The new research challenge is to include the consideration of territorial aspects to define and design the worst‐ and best‐case reference scenarios to assess strict environmental performances of IS.  相似文献   

12.
To date, 18 genera of imperfect and ascomycetous fungi have been recognized to produce ca. 700 individual sequences of peptaibiotics. These are linear polypeptide antibiotics which i) have a molecular weight between 500 and 2,200 Dalton, thus containing 5-21 residues; ii) show a high content of alpha-aminoisobutyric acid; iii) are characterized by the presence of other nonproteinogenic amino acids and/or lipoamino acids; iv) possess an acylated N-terminus, and v) have a C-terminal residue that, in most of them, consists of a free or acetylated amide-bonded 1,2-amino alcohol, but might also be an amine, amide, free amino acid, 2,5-dioxopiperazine, or sugar alcohol. From April 2003 until present, ca. 300 new individual sequences of peptaibiotics have been published in the literature, but most of them have not yet been included in databases. To summarize these new sequences and novel constituents, as well as to introduce fungal species hitherto unknown as producers of peptaibiotics, the relevant literature is reviewed. Furthermore, ecophysiological and taxonomic aspects of the producing fungi are discussed.  相似文献   

13.
Culturing of microalgae as an alternative feedstock for biofuel production has received a lot of attention in recent years due to their fast growth rate and ability to accumulate high quantity of lipid and carbohydrate inside their cells for biodiesel and bioethanol production, respectively. In addition, this superior feedstock offers several environmental benefits, such as effective land utilization, CO(2) sequestration, self-purification if coupled with wastewater treatment and does not trigger food versus fuel feud. Despite having all these 'theoretical' advantages, review on problems and issues related to energy balance in microalgae biofuel are not clearly addressed until now. Base on the maturity of current technology, the true potential of microalgae biofuel towards energy security and its feasibility for commercialization are still questionable. Thus, this review is aimed to depict the practical problems that are facing the microalgae biofuel industry, covering upstream to downstream activities by accessing the latest research reports and critical data analysis. Apart from that, several interlink solutions to the problems will be suggested with the purpose to bring current microalgae biofuel research into a new dimension and consequently, to revolutionize the entire microalgae biofuel industry towards long-term sustainability.  相似文献   

14.
Microbial enzymes play a critical role in organic matter decomposition and enzyme activity can dynamically respond to shifts in inorganic nutrient and substrate availability, reflecting the nutrient and energy limitation of the microbial community. We characterized microbial enzyme response to shifting nitrogen (N) and phosphorus (P) availability across terrestrial and aquatic environments at the Bear Brook Watershed in Maine, the site of a whole-watershed N enrichment experiment. We compared activity of β-1,4-glucosidase (BG); β-1,4-N-acetylglucosaminidase (NAG); acid phosphatase (AP) in soil, leaf litter in terrestrial and stream habitats and stream biofilms in a reference and N enriched watershed, representing whole-ecosystem response to chronic N enrichment. In addition, we used shorter, experimental P enrichments to address potential P limitation under ambient and elevated N availability. We found that BG and NAG activity were not affected by the long-term N enrichment in either habitat. Enhanced P limitation due to N enrichment was evident only in the aquatic habitats with 5- and 8-fold higher treated watershed AP activity in stream biofilms and stream litter, respectively. Acute P additions reduced AP activity and increased BG activity and these effects were also most pronounced in the streams. The stoichiometry of enzyme activity was constrained across ecosystem compartments with regression slopes for lnBG:lnNAG, lnBG:lnAP, and lnNAG:lnAP close to 1, ranging 1.142–1.241. We found that microbial enzyme response to shifting N and P availability varied among watershed compartments, typically with stronger effects in aquatic habitats. This suggests that understanding the response of ecosystem function to disturbance at the watershed scale requires simultaneous consideration of all compartments.  相似文献   

15.
16.
Analysis of several different schemes for industrial FAME production at higher pressure and temperature (catalytic or non-catalytic synthesis) was realized with the aim to find the best route to reduce the energy consumption (EC) and to improve the life cycle energy efficiency. Obtained results indicated that the EC (MJ/kg FAME) mainly depends on degree of conversion of triglycerides being almost 25% smaller if degree of conversion increase from 97 mass% to complete conversion. Further significant decrease of EC might be obtained at subcritical conditions but only after substantial decrease of methanol to oil molar ratio (from 42 to 15) which requires use of appropriate catalyst. On account of that, the kinetics of heterogeneous catalyzed methanolysis of triglycerides was analyzed using data published in literature (CaO) as well as own experimental data (K2CO3/Al–O–Si) with a goal to obtain reliable kinetic rate constant which might be used for process simulation.This study shows that if heterogeneous process of biodiesel synthesis is realized at subcritical conditions then further decrease of EC is possible.  相似文献   

17.
Lactic acid is a product that finds several applications in food, cosmetic, pharmaceutical and chemical industries. The main objective of this work was the development of a bioprocess to produce L(+)-lactic acid using soybean vinasse as substrate. Among ten strains, Lactobacillus agilis LPB 56 was selected for fermentation, due to its ability to metabolize the complex oligosaccharides. Fermentation was conducted without need for supplementary inorganic nitrogen sources or yeast extract. Kinetic and yield parameters determined at laboratory scale were 0.864 and 0.0162 for YP/S and YX/S, 0.0145 g/L h (rx), 1.32 g/L h (rs) and 1.13 g/L h (rp). The use of vinasse enriched with soybean molasses provided higher lactic acid concentration (138 g/L), the best proportion of inoculum being 25% (v/v). After scale-up to a pilot plant, kinetic and yield parameters were 0.849 and 0.0353 for YP/S and YX/S, 0.0278 g/L h (rx), 0.915 g/L h (rs) and 0.863 g/L h (rp).  相似文献   

18.
Correlations between the amount of energy received by an assemblage and the number of species that it contains are very general, and at the macro-scale such species-energy relationships typically follow a monotonically increasing curve. Whilst the ecological literature contains frequent reports of such relationships, debate on their causal mechanisms is limited and typically focuses on the role of energy availability in controlling the number of individuals in an assemblage. Assemblages from high-energy areas may contain more individuals enabling species to maintain larger, more viable populations, whose lower extinction risk elevates species richness. Other mechanisms have, however, also been suggested. Here we identify and clarify nine principal mechanisms that may generate positive species-energy relationships at the macro-scale. We critically assess their assumptions and applicability over a range of spatial scales, derive predictions for each and assess the evidence that supports or refutes them. Our synthesis demonstrates that all mechanisms share at least one of their predictions with an alternative mechanism. Some previous studies of species-energy relationships appear not to have recognised the extent of shared predictions, and this may detract from their contribution to the debate on causal mechanisms. The combination of predictions and assumptions made by each mechanism is, however, unique, suggesting that, in principle, conclusive tests are possible. Sufficient testing of all mechanisms has yet to be conducted, and no single mechanism currently has unequivocal support. Each may contribute to species-energy relationships in some circumstances, but some mechanisms are unlikely to act simultaneously. Moreover, a limited number appear particularly likely to contribute frequently to species-energy relationships at the macro-scale. The increased population size, niche position and diversification rate mechanisms are particularly noteworthy in this context.  相似文献   

19.
The International Journal of Life Cycle Assessment - From 2010, more than half of human beings live in cities and global urbanization is growing at a fast pace. This leads to threats for the...  相似文献   

20.
The diversity and composition of yeast populations may greatly impact wine quality. This study investigated the yeast microbiota in two different types of wine fermentations: direct inoculation of a commercial starter versus pied de cuve method at an industrial scale. The pied de cuve fermentation entailed growth of the commercial inoculum used in the direct inoculation fermentation for further inoculation of additional fermentations. Yeast isolates were collected from different stages of wine fermentation and identified to the species level using Wallersterin Laboratory nutrient (WLN) agar followed by analysis of the 26S rDNA D1/D2 domain. Genetic characteristics of the Saccharomyces cerevisiae strains were assessed by a rapid PCR-based method, relying on the amplification of interdelta sequences. A total of 412 yeast colonies were obtained from all fermentations and eight different WL morphotypes were observed. Non-Saccharomyces yeast mainly appeared in the grape must and at the early stages of wine fermentation. S. cerevisiae was the dominant yeast species using both fermentation techniques. Seven distinguishing interdelta sequence patterns were found among S. cerevisiae strains, and the inoculated commercial starter, AWRI 796, dominated all stages in both direct inoculation and pied de cuve fermentations. This study revealed that S. cerevisiae was the dominant species and an inoculated starter could dominate fermentations with the pied de cuve method under controlled conditions.  相似文献   

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