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1.
Over the years, the biological activities of seaweeds could have gained a considerable research interest because of their specific functional compounds, which may not be available in land plants. Thus, efforts at discovery of novel metabolites from seaweeds over the past years have yielded a considerable amount of new active compounds. In addition, studies about the extraction of active compounds from natural products have attracted special attention in the last recent years. Potent biologically active compounds of seaweeds have been demonstrated to play a significant role in prevention of certain degenerative diseases such as cancer, inflammation, arthritis, diabetes and hypertension. Therefore, seaweed derived active components, whose immense biochemical diversity looks like to become a rich source of novel chemical entities for the use as functional ingredients in many industrial applications such as functional foods, pharmaceuticals and cosmeceuticals. Thus, the interest in the extraction of active compounds from seaweeds is obvious. However, the physical and chemical barriers of the plant material become the key drawbacks of such extraction process. Therefore, enhanced release and recovery of active compounds attached to the cells have been addressed. Taken together, the aim of this communication is to discuss the potential use of enzyme treatment as a tool to improve the extraction efficiency of bioactive compounds from seaweeds. 相似文献
2.
Uncaria species (Gouteng in Chinese) have been used as a plant medicine to treat ailments of cardiovascular and central nervous systems. As the main alkaloid constituent of Uncaria species, isorhynchophylline has drawn extensive attention toward antihypertensive and neuroprotective activities in recent years. Isorhynchophylline mainly acts on cardiovascular and central nervous systems diseases including hypertension, brachycardia, arrhythmia, and sedation, vascular dementia, and amnesia. Isorhynchophylline also has effects on anticoagulation, inhibition vascular smooth muscle cell apoptosis and proliferation, anti-multidrug resistant of lung cells, anti-endotoxemic, and antispasmodic. The active mechanisms are related to modulation on calcium ion channel, protection neural and neuroglial cells against β-amyloid(25-35)-induced neurotoxicity and via inducing autophagy. As a candidate drug of several cardiovascular and central nervous systems diseases, isorhynchophylline will attract scientists to pursue the potential related pharmacological effects and its mechanism with new technologies. But relatively few clinical application of isorhynchophylline has been conducted on its pharmacological activities. It requires more in vivo validations and further investigations of antihypertensive and neuroprotective mechanisms of isorhynchophylline. 相似文献
3.
The use of phytotherapy to treat human diseases has its roots in pre-historical times. Despite the modern advances achieved in the field of synthetic chemistry, the most efficient drugs available have their genesis directly or indirectly related with the vegetal kingdom. Indigenous communities have long used plant extracts to treat illnesses. Many of these extracts have shown effective action, with new bioactive compounds being extracted and screened every year. These extracts have also proven to be good sources of therapeutic agents to the treatment of Leishmaniasis. This work highlights some of these agents, while trying to emphasize the importance of plants as a source of new and powerful drugs against this widespread disease. 相似文献
4.
《Fitoterapia》2013
The effectiveness of Hibiscus sabdariffa L. (HS) in the treatment of risk factors associated with cardiovascular disease is assessed in this review by taking a comprehensive approach to interpreting the randomized clinical trial (RCT) results in the context of the available ethnomedical, phytochemical, pharmacological, and safety and toxicity information. HS decoctions and infusions of calyxes, and on occasion leaves, are used in at least 10 countries worldwide in the treatment of hypertension and hyperlipidemia with no reported adverse events or side effects. HS extracts have a low degree of toxicity with a LD50 ranging from 2,000 to over 5,000 mg/kg/day. There is no evidence of hepatic or renal toxicity as the result of HS extract consumption, except for possible adverse hepatic effects at high doses. There is evidence that HS acts as a diuretic, however in most cases the extract did not significantly influence electrolyte levels. Animal studies have consistently shown that consumption of HS extract reduces blood pressure in a dose dependent manner. In RCTs, the daily consumption of a tea or extract produced from HS calyxes significantly lowered systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults with pre to moderate essential hypertension and type 2 diabetes. In addition, HS tea was as effective at lowering blood pressure as the commonly used blood pressure medication Captropril, but less effective than Lisinopril. Total cholesterol, low-density lipoprotein cholesterol (LDL-C), and triglycerides were lowered in the majority of normolipidemic, hyperlipidemic, and diabetic animal models, whereas high-density lipoprotein cholesterol (HDL-C) was generally not affected by the consumption of HS extract. Over half of the RCTs showed that daily consumption of HS tea or extracts had favorable influence on lipid profiles including reduced total cholesterol, LDL-C, triglycerides, as well as increased HDL-C. Anthocyanins found in abundance in HS calyxes are generally considered the phytochemicals responsible for the antihypertensive and hypocholesterolemic effects, however evidence has also been provided for the role of polyphenols and hibiscus acid. A number of potential mechanisms have been proposed to explain the hypotensive and anticholesterol effects, but the most common explanation is the antioxidant effects of the anthocyanins inhibition of LDL-C oxidation, which impedes atherosclerosis, an important cardiovascular risk factor. This comprehensive body of evidence suggests that extracts of HS are promising as a treatment of hypertension and hyperlipidemia, however more high quality animal and human studies informed by actual therapeutic practices are needed to provide recommendations for use that have the potential for widespread public health benefit. 相似文献
5.
Kim Jinwon Hiltpold Ivan Jaffuel Geoffrey Sbaiti Ilham Hibbard Bruce E. Turlings Ted C. J. 《Journal of pest science》2021,94(4):1197-1208
Journal of Pest Science - Entomopathogenic nematodes (EPN) have great potential as biological control agents against root-feeding insects. They have a rapid and long-lasting mode of action, minimal... 相似文献
6.
《Fitoterapia》2013
Presently herbal medicines are being used by about 80% of the world population for primary health care as they stood the test of time for their safety, efficacy, cultural acceptability and lesser side effects. The discovery of platelet activating factor antagonists (PAF antagonists) during these decades are going on with different framework, but the researchers led their efficiency in studying in vitro test models. Since it is assumed that PAF play a central role in etiology of many diseases in humans such as asthma, neuronal damage, migraine, cardiac diseases, inflammatory, headache etc. Present days instinctively occurring PAF antagonist exists as a specific grade of therapeutic agents for the humans against these and different diseases either laid hold of immunological or non-immunological types. Ginkgolide, cedrol and many other natural PAF antagonists such as andrographolide, α-bulnesene, cinchonine, piperine, kadsurenone, different Piper species' natural products and marine origin plants extracts or even crude drugs having PAF antagonist properties are being used currently against different inflammatory pathologies. This review is an attempt to summarize the data on PAF and action of natural PAF antagonists on it, which were evaluated by in vivo and in vitro assays. 相似文献
7.
《Fitoterapia》2014
Schisandra chinensis fruit extract (SCE) has traditionally been used as an oriental medicine for the treatment of various human diseases, including cardiovascular disease. Advances in scientific knowledge and analytical technologies provide opportunities for translational research involving S. chinensis; such research may contribute to future drug discovery. To date, emerging experimental evidence supports the therapeutic effects of the SCE or its bioactive lignan ingredients in cardiovascular disease, unraveling the mechanistic basis for their pharmacological actions. In the present review, we highlight SCE and its lignans as promising resources for the development of safe, effective, and multi-targeted agents against cardiovascular disease. Moreover, we offer novel insight into future challenges and perspective on S. chinensis research to future clinical investigations and healthcare strategies. 相似文献
8.
《Fitoterapia》2013
There are 350,000 hepatitis B virus (HBV) carriers all over the world. Chronic HBV infection is at a high risk of developing liver cirrhosis and hepatocelluar carcinoma (HCC), and heavily threatened people's health. Two kinds of drugs approved by FDA for anti-HBV therapy are immunomodulators (interferon α, pegylated-interferon α) and nucleos(t)ide analogues (lamivudine, adefovir dipivoxil, entecavir, telbivudine, and tenofovir disoproxil fumarate). These drugs have been proved to be far from being satisfactory due to their low specificity, side effects, and high rate of drug resistance. There is an urgent need to discover and develop novel effective anti-HBV drugs. With vast resources, various structures, diverse biological activities and action mechanisms, as well as abundant clinical experiences, botanical agents become a promising source of finding new anti-HBV drugs. This review summarizes the recent research and development of anti-HBV agents derived from botanical origin on their sources and active components, inhibitory effects and possible toxicities, as well as action targets and mechanisms, and also addresses the advantages and the existing shortcomings in the development of botanical inhibitors. This information may not only broaden the knowledge of anti-HBV therapy, and offer possible alternative or substitutive drugs for CHB patients, but also provides considerable information for developing new safe and effective anti-HBV drugs. 相似文献
9.
天然的植物活性物质对于人体健康状态的维持起着重要作用。类胡萝卜素、生育酚、皂苷化合物等植物活性物质的结构、性质、功能及作用机制相继被研究,它们陆续被开发利用为保健品,药品等产品。广泛存在于各种软果、坚果等植物组织中的活性组分鞣花酸是一种多酚二内酯,是没食子酸的二聚衍生物,具有抗氧化、抗炎、抗增殖、抗病毒等多种生物学效应,在癌症治疗和化学预防方面具有强大潜力。随着相关研究的深入,鞣花酸的作用机制和药用价值不断被挖掘,它将在疾病治疗、美容保健等方面表现出积极作用。对近几年鞣花酸的相关研究进展进行了阐述,以期为鞣花酸的后续研究提供参考。 相似文献
10.
Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution. The presence of saponins has been reported in more than 100 families of plants out of which at least 150 kinds of natural saponins have been found to possess significant anti-cancer properties. There are more than 11 distinguished classes of saponins including dammaranes, tirucallanes, lupanes, hopanes, oleananes, taraxasteranes, ursanes, cycloartanes, lanostanes, cucurbitanes and steroids. Due to the great variability of their structures, saponins always display anti-tumorigenic effects through varieties of antitumor pathways. In addition, there are a large amount of saponins that still either remain to be trapped or studied in details by the medicinal chemists. This article reviews many such structures and their related chemistry along with the recent advances in understanding mechanism of action and structure–function relationships of saponins at the molecular and cellular levels. These aglycones have been described and their classification and distribution have been listed in the review. Some special saponins with strong antitumor effects have also been exhibited. Ginsenosides, belonging to dammaranes, have been found beneficial targeted on inhibition of tumor angiogenesis by suppressing its inducer in the endothelial cells of blood vessels, and then on prevention of adhering, invasion, and metastasis of tumor cells. Dioscin, one of the steroidal saponins, and its aglycone diosgenin also have been extensively studied on its antitumor effect by cell cycle arrest and apoptosis. Other important molecules discussed include oleanane saponins such as avicins, platycodons, saikosaponins, and soysaponins along with tubeimosides. 相似文献
11.
Sautebin L 《Fitoterapia》2000,71(Z1):S48-S57
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most used drugs worldwide, in spite of their renal and gastric side effects. Medicinal plants may represent a useful source of new effective therapeutic agents, particularly considering the new findings concerning the mediators of inflammation, such as prostaglandins and nitric oxide. In fact, the discovery of two isoforms of the enzyme cyclooxygenase, which catalyzes the conversion of arachidonic acid to prostaglandins, has opened new interesting perspectives in the treatment of inflammatory diseases. As cyclooxygenase, also nitric oxide synthase, the enzyme which converts L-arginine to nitric oxide, exists in two isoforms. It appears that the constitutive isoforms of both enzymes (cyclooxygenase-1 and constitutive nitric oxide synthase) have a regulatory-physiological role, whereas the inducible isoforms (cyclooxygenase-2 and inducible nitric oxide synthase) are involved in inflammation. A number of medicinal plants have been screened for their ability to inhibit cyclooxygenase-2 and/or inducible nitric oxide synthase activity and/or expression. 相似文献
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14.
Ok Kyu Park Jung Hoon Choi Joon Ha Park In Hye Kim Bing Chun Yan Ji Hyeon Ahn Seung-Hae Kwon Jae-Chul Lee Young Sup Kim Misook Kim Il-Jun Kang Jong-Dai Kim Yun Lyul Lee Moo-Ho Won 《Fitoterapia》2012
We observed neuroprotective effects of five major lipophilic diterpenes derived from Danshen (Radix Salvia miltiorrhiza) extract, such as cryptotanshinone (CTs), dihydrotanshinone I (DTsI), tanshinone I (TsI), tanshinone IIA (TsIIA) and tanshinone IIB (TsIIB), in the hippocampal CA1 region (CA1) against transient ischemic damage in gerbils. These diterpenes were administered 30 min before ischemia–reperfusion and the animals were sacrificed 4 days after ischemia–reperfusion. In the vehicle-treated-group, cresyl violet positive (CV+) cells and neuronal nuclei (NeuN)+ neurons were significantly decreased in the CA1. However, in the TsI- and CTs-treated-ischemia-groups, CV+ and NeuN+ neurons were abundant in the CA1. In the other groups, the number of CV+ and NeuN+ neurons was less than the TsI- and CTs-treated-ischemia-groups. In addition, gliosis induced by ischemic damage was apparently blocked in the TsI- and CTs-treated-ischemia-groups. These results suggest that TsI and CTs among five major lipophilic diterpenes have strong potentials for neuroprotection against ischemic damage. 相似文献
15.
Steroidal saponins have long attracted scientific attention, due to their structural diversity and significant biological activities. Total steroidal saponins (TSS) extracted from the rhizomes of Dioscorea zingiberensis C.H. Wright (DZW) constitute an effective treatment for cardiovascular disease. However, the active constituents contained in DZW rhizomes and their pharmacological properties are not fully understood. The aim of this work is to determine and quantify the active constituents in DZW rhizomes using fingerprint technique, and evaluate its anti-thrombotic activity using inferior vena cava ligation thrombosis rat model and pulmonary thrombosis mice model after being gavaged with TSS for 1 or 2 weeks. In the study, a chemical fingerprint method was firstly established and validated to quantify and standardize TSS from DZW rhizomes including parvifloside, protodeltonin, protodioscin, protogracillin, zingiberensis saponin, deltonin, dioscin and trillin. TSS extracted from DZW rhizomes were showed to have the inhibitions on platelet aggregation (PAG) and thrombosis, and prolong activated partial thromboplastin time (APTT), thrombin time (TT), and prothrombin time (PT) in a dose-dependent manner in rats. TSS also prolonged the bleeding time and clotting time in a dose-dependent manner in mice. The results indicate that TSS could inhibit thrombosis by both improving the anticoagulation activity and inhibiting PAG action, suggesting that TSS from DZW rhizomes have the potential to reduce the risk of cardiovascular diseases by anti-thrombotic action. 相似文献
16.
New Forests - Deposition rates of NH4+ and NO3?, two naturally occurring forms of nitrogen (N), vary worldwide. Here, we discuss the combined effect of deposition of N forms on plant growth... 相似文献
17.
Hanne K. Sjølie Greg S. Latta Erik Trømborg Torjus F. Bolkesjø Birger Solberg 《Scandinavian Journal of Forest Research》2015,30(1):60-72
Forest sector models are widely used for policy and economic analyses. Basic assumptions vary considerably between models, but little attention has been paid to the impacts these differences may have on model results. Norway provides a great opportunity to fill this void as it has two forest sector models currently in use based on different modeling assumptions, but sharing the same data source. In one model, agents are assumed to be myopic in the meaning that they rely only on the current market conditions. Harvest behavior is in this model based on econometric relations and exogenous forest growth rates. The second model approach employs extensive forest data and assumes that agents have perfect information over the model time horizon. We discuss the differences between the two modeling approaches and compare quantitatively the model results of two case studies. However, both types of models are rather sensitive to changes in assumptions and data. The strengths and weaknesses of the two model approaches and their appropriateness for responding to the study questions should be considered when choosing modeling methodology. Using both models in parallel removes the uncertainty caused by the foresight assumption/optimization routine and thus provides in total more information. 相似文献
18.
Rapid economic growth of the Khasia people has resulted from a most successful betel leaf farming system practiced within
the fringe of reserved forests, where government policies have facilitated effective use of the local people as a labour force
for production, protection and conservation of biodiversity of the surrounding forests. Khasia tribes have traditionally grown
betel leaf plants on naturally occurring trees. Deforestation is a serious problem in Bangladesh, whereas the Khasia people
living within forests are protecting trees for their livelihood, including selling betel leaf, collecting fuelwood and consuming
and selling fruits from support trees. It is a profitable yet sustainable forest production system, maintaining soil fertility,
stable production and optimal family size, and has created employment opportunities for the people living within and outside
the forests. It has enhanced the supply of socially required betel leaf to the local markets, contributed to price stability,
and generated some export revenue. However, the revenue of growers has been reduced by plant diseases and the capture of resource
rent by middlemen. Economic benefits could be further increased through government initiatives to improve management and the
marketing system.
This paper is based on a presentation at the International Conference on Economics of Sustainable Forest Management, University
of Toronto, Canada, May 20–22, 2004. 相似文献
19.
T. Stewart 《Agroforestry Systems》1992,18(3):225-244
The Negrito (Ati) tribe of Nagpana, Iloilo, Philippines has traditionally been dependent on shifting cultivation and on hunting and gathering of non-timber forest products for its livelihood. In recent decades the Ati have derived increasing income from wage labor for adjacent landowners and from permanent rice cultivation. The consequent clearing of residual forests has resulted in extensive soil degradation, reduced crop yields, and loss of both commercial and subsistence non-timber forest products.Various agroforestry systems which incorporate permanent tree crops into traditional systems have great potential to reverse these losses. This study analyzes the economic sustainability of four different land-use options for the Ati. The net present value (NPV) of a system which incorporates both sustainable use of the existing forest and plantations of fast-growing tree species on agricultural lands is superior to all other alternatives. Social and environmental benefits from this system further justify implementation. Any recommendations to develop such an option must take into account the constraining factors typical of such upland communities. 相似文献
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