Bioactive isolated from plants

Often, planar chromatography is used as a preparative step for the isolation of single components or classes of components for further chromatographic separation or spectroscopic elucidation. Many planar chromatographic methods have been developed for the analysis of food products, bioactive compounds from plant materials, and essential oils. 

Bioactive Pectic Polysaccharides Isolated from Plants. 77... 

Ultrasonically assisted extraction is also widely used for the isolation of effective medical components and bioactive principles from plant material [195]. The most common application of low-intensity ultrasound is as an analytical technique for providing information about the physico-chemical properties of foods, such as in the analysis of edible fats and oils (oil composition, oil content, droplet size of emulsions, and solid fat content) [171,218]. Ultrasonic techniques are also used for fluids characterisation [219]. 

Isolation of bioactive heterocycles from plants 92YGK963. 

The discovery that several major anticancer drugs, originally isolated from plants, are produced by associated endophytic fungi (Section III.B.3.) opens up further avenues for exploring the large-scale production of plant-derived pharmaceuticals. Likewise, the probable role of microbial symbionts in the production of bioactive agents from marine macroorganisms (Section III.B.4.) offers... 

Of a total of 43 Sri Lankan plants from which alkaloids have been isolated, 17 are claimed to have applications in traditional systems of medicine (Table III). As stated in the Introduction, many of these investigations were not driven by the claims of medicinal properties. Interestingly, several bioactive alkaloids have been isolated from plants with no claims of any medicinal applications. 

ABSTRACT More than 200 naturally occurring oligostilbenes isolated from plant kingdom are grouped into I-V structural types. They are a special kind of polyphenolic natural products with multi-faceted bioactivities. This article will review their classification, distribution, spectral characteristics, biological activities (anti-fungal, antibacterial, antioxidant, anti-inflammatory and anticarcinogenic activities, etc.) and mimetic biosynthesis. 

There are many examples of such JH mimics isolated from plants [42, 103]. In the following section, the activities of four of the better characterized JH mimics, juvocimene I and II, bakuchiol and echinolone, are reviewed to illustrate the diversity of the compounds which exhibit JH activity (Fig. (6)) and the range of bioactivity (Table 4). 

The bioactivities of precocene I, 7-methoxy-2,2-dimethyl chromene, and precocene II, 6,7-dimethoxy-2,2-dimethyl chromene, are well established (Fig. (7)). These two compounds have been isolated from plants throughout the family Asteraceae [129-136, 154]. The chemical data for these compounds and references for their synthesis are compiled in Appendix IV, Tables 13 and 14. There is a wealth of information on the effects of these compounds on various insect species [42, 137]. For simplicity, we will focus on the effects of precocene II on the susceptible Hemipteran bug, Oncopeltus fasciatus. 

The bioactive compounds isolated from plants and responsible for the medicinal properties mentioned here and different health -improving effects are named secondary metabolites [9]. It is generally believe that they do not play an essential role in plant growth and development. However, they participate in plant adaptation responses and defense functions. It is well known that these compounds play an important role in their survival in the ecosystem because they are involved in the resistance against pests, diseases and other functions such as attraction of pollinators and interactions with organisms of their enviromnent [1, 6, 9]. 

Phenols are considered important bioactive compounds isolated from plants because of their potential role in human health management. Phenolic structure consists of an aromatic ring with attached hydroxyl groups. Based on structural differences, phenols can be classified into groups and components. The broad classifications include phenolic acids, stilbenes, lignans, and fiavonoids [4]. 

In general, three conventional methods were used for the extraction of bioactive compounds such as solvents, steam, and supercritical fluids. On a global level, water extraction is practised while making cofiee or tea. Basically, pretreated plant material is extracted with hot water which takes up the flavor, taste, and color of the components. After filtration, the extract is ready for consumption. In case of the isolation of certain bioactive compounds from plant material by means of liquid extraction, some technological problems needs to be resolved [3]. First the plant material has to be pretreated in order to obtain reasonable extraction yields. Another problem is the need for special solvents to be used in the extraction procedure [4]. More recently, attention has been focussed towards the isolation of specific compounds that can be used in the food industry. Of particular interest is the isolation of bioactive compounds, aromas, and fiiagrances from plants and fruits [5,6]. The sequential extractions of bioactives using nonpolar to polar solvents are depicted in Figure 7.1. Various polarity solvents are reported as follows (1) nonpolar solvents (hexane, heptanes, petroleum ether,... 

Abstract Recent chemical studies on the marine soft corals and terrestrial plants have lesnlted in the isolation of several novel componnds. The soft corals, Pseudopterogorgia elisabethae and Cladiella species yielded several novel terpenoids, exhibiting antimicrobial activities. New steroids were isolated from terrestrial fungi, Mucor plumbeus and Coprims micaceus. Phytochemical studies on the Buxus hyrcana, collected from Iran, have yielded steroidal bases. This revdew describes the new natiual products exhibiting different bioactivities from the aforementioned sources. 

Bioactivity-Guided Fractionation, Isolation and Purification of the Compounds from Plants... 

Andrographolide, a labdane-diterpenoid lactone, is the principal bioactive chemical constituent of Andrographis paniculata (Brum. F.) Nees (family Acanthaceae) this prime constituent is mainly concentrated in leaves and can easily be isolated from the crude plant extracts as crystalline... 

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