Preparation of medicinal plants for experimental purposes is an initial step and key in achieving quality research outcome. It involves extraction and determination of quality and quantity of bioactive constituents before proceeding with the intended biological testing. The primary objective of this study was to evaluate various methods used in the preparation and screening of medicinal plants in our daily research. Although the extracts, bioactive fractions, or compounds obtained from medicinal plants are used for different purposes, the techniques involved in producing them are generally the same irrespective of the intended biological testing. The major stages included in acquiring quality bioactive molecule are the selection of an appropriate solvent, extraction methods, phytochemical screening procedures, fractionation methods, and identification techniques. The nitty-gritty of these methods and the exact road map followed solely depends on the research design. Solvents commonly used in extraction of medicinal plants are polar solvent (e.g., water, alcohols), intermediate polar (e.g., acetone, dichloromethane), and nonpolar (e.g., n-hexane, ether, chloroform). In general, extraction procedures include maceration, digestion, decoction, infusion, percolation, Soxhlet extraction, superficial extraction, ultrasound-assisted, and microwave-assisted extractions. Fractionation and purification of phytochemical substances are achieved through application of various chromatographic techniques such as paper chromatography, thin-layer chromatography, gas chromatography, and high-performance liquid chromatography. Finally, compounds obtained are characterized using diverse identification techniques such as mass spectroscopy, infrared spectroscopy, ultraviolet spectroscopy, and nuclear magnetic resonance spectroscopy. Subsequently, different methods described above can be grouped and discussed according to the intended biological testing to guide young researchers and make them more focused.

Preparation of Medicinal Plants: Basic Extraction and Fractionation Procedures for Experimental Purposes.

Increased demand for food to feed the ever-growing population led to development and adoption of synthetic chemicals as a quick and effective strategy of managing crop pests and diseases. However, overreliance on synthetic pesticides is discouraged due to their detrimental effects on human health, the environment, and development of resistant pest and pathogen strains. This, coupled with increasing demand for organically produced foods, stimulated search for alternative approaches and botanical pesticides are particularly gaining importance. Botanical pesticides are efficacious in managing different crop pests, inexpensive, easily biodegraded, have varied modes of action, their sources are easily available and have low toxicity to non-target organisms. Their varied modes of action are attributed to the phytochemical composition in different plants. Therefore, they can be incorporated into integrated pest management systems and contribute to sustainable agricultural production. Nevertheless, botanical pesticides have not been fully adopted due to challenges in formulation and commercialization which are attributed to lack of chemical data and positive controls. Many publications have featured botanical pesticides with skewed interest towards management of insect pests. This review brings together information regarding botanical pesticides, their phytochemical composition and mechanisms of action against pests of importance in agricultural production. The paper also presents chemistry data of selected botanical pesticides, their biodegradation, role in integrated pest management and the challenges facing their adoption and utilization for sustainable crop pest management.

Phytochemical activity and role of botanical pesticides in pest management for sustainable agricultural crop production

Phosphorus (P) is one of the most important minerals required for plant growth occupying a strong position among soil macro nutrients. Soil P deficiency is often fulfilled by phosphate fertilizers....

Phosphorus and phosphate solubilizing bacteria: Keys for sustainable agriculture

This work aims at giving an updated picture of the strict interaction between main plant biologically active compounds and botanicals. The main features of the emerging class of dietary supplements, the botanicals, are highlighted. Focus is also on the definition of actual possibilities of study approach and research strategies. Examples of innovative directions are given: assessment of interaction of bioactive compounds, chemometrics and the new goal of biorefineries. Current models of existing databases, such as plant metabolic pathways, food composition, bioactive compounds, dietary supplements, and dietary markers, are described as usable tools for health research. The need for categorization of botanicals as well as for the implementation of specific and dedicated databases emerged, based on both analytical data and collected data taken from literature throughout a harmonized and standardized approach for the evaluation of an adequate dietary intake.

https://www.mdpi.com/1420-3049/23/8/1844/pdf

From Plant Compounds to Botanicals and Back: A Current Snapshot

Alkaloids are a large cluster of molecules found in Mother Nature all over the world. They are all secondary compounds and collection of miscellaneous elements and biomolecules, derived from amino acids or from transamination. This diverse chemical group is categorized, based on the amino acids that deliver their nitrogen atom and part of their skeleton. Alkaloids from a similar origin or having the same basic nucleus may have dissimilar biosynthetic pathways and different biological activity. They are derived from l -phenylalanine, l -tyrosine, anthranilic acid or acetate, l -histidine, l -ornithine, nicotinic acid, and l -lysine. Apart from other types of alkaloids, indole, tropane, and isoquinoline alkaloids are very important. People from all over the world are using them in their everyday life. Alkaloids can also have an animal origin, which may be endogenous or exogenous. This chapter highlights the phytochemistry of the main representatives among the diverse group of alkaloids. This chapter also focuses on their extraction, purification, fractionation, identification, and quantification procedures. A fundamental understanding of the biological activity of important alkaloids is also highlighted in this chapter. With the potential of revealing new compounds and diverse pharmacological properties, alkaloids still embrace a great potential for the future of drug discovery.

Analysis of alkaloids (indole alkaloids, isoquinoline alkaloids, tropane alkaloids)

Plants are recognized in the pharmaceutical industry due to their broad spectrum of structural diversity and their wide range of pharmacological activities. The biological active compounds that are present in plants referred as phytochemicals. These phytochemicals derived from different parts of plants such as leaves, barks, seed, seed coat, flowers, roots and pulps and thereby used as sources of direct medicinal agents. Phytochemistry describes the large number of secondary metabolic compounds present in the plants. The plants are the reservoirs of naturally occurring chemical compounds and of structurally diverse bioactive molecules. The extraction of bioactive compounds from the plants and their quantitative and qualitative estimation is important for exploration of new biomolecules to be used by pharmaceutical and agrochemical industry directly or can be used as a lead molecule to synthesize more potent molecules. This review mostly highlighted on the analytical methodologies, which includes the extraction methods and the analysis of bioactive compounds present in the plant extracts through the various techniques involving the applications of chromatographic techniques such as HPLC (High Performance Liquid Chromatography), TLC (Thin Layer Chromatography), HPTLC (High Performance Thin Layer Chromatography), OPLC (Optimum Performance Laminar Chromatography), GC (Gas Chromatography), PC (Paper Chromatography), CC (Column Chromatography) and it’s detection through Fourier Transform Infra-Red spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), and Mass Spectrometry (MS).

https://www.phytojournal.com/archives/2017/vol6issue1/PartA/6-1-23-924.pdf

Phytochemicals: Extraction methods, identification and detection of bioactive compounds from plant extracts

To meet the demand of overgrowing population it is the need of agrarian community to enhance the yield and future food supply. To overcome these problems, efforts needed to focus the soil biological system and the agro-ecosystem for better understanding the complex processes and their interactions for governing the stability of agricultural land. The green revolution has been proved the most intellectual human activities contributing global food security and, consequently, changes the face of developing countries, such as India, from being fooddeficient to having a food surplus. In present conditions there is an urgent need of second green revolution to increase the food production by around 50% in coming next 20 International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 1 (2017) pp. 844-852 Journal homepage: http://www.ijcmas.com

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Phosphate Solubilizing Microbes: An Overview

In the present study extracts of leaf, bark, seed, seed coat and roots of Jatropha curcas were extracted using soxhlet extraction method with various solvents. Methanol was found to be the best extractant amongst all the solvents. In order to prescreen, the methanol and solvent extract were then subjected to check for insecticidal activity if any. The biological and phytochemical studies of Jatropha curcas were evaluated against third instar larvae of diamond back moth (Plutella xylostella) and Helicoverpa armigera by Leaf dip method. Antifeedant activity was observed in case of leaf extract against Helicoverpa armigera with total larval weight reduction of 36.27% after 24 hrs when they were fed on cotton leaf treated with the extract, but even after replacing the fresh cotton leaf the weight reduction was 42.08% (after 48 hrs) and 41.55% (after 72 hrs). The seed coat extract was most effective against Plutella xylostella and showed highest mortality 100% at 5% as compared to other extracts whereas in case of Helicoverpa armigera seed coat extract was most effective and showed highest mortality 10, 40 and 60% at 5, 10 and 15% concentration respectively. The results suggested that Jatropha curcas has good insecticidal/antifeedant activity therefore making it ideal potential option for incorporation into pest management program.

https://www.entomoljournal.com/archives/2017/vol5issue1/PartA/5-1-40-257.pdf

Screening of insecticidal activity of Jatropha Curcas (L.) against diamond back moth and Helicoverpa Armigera

The crude methanolic extracts of Jatropha curcas (L.) were screened (leaf, bark, seed, seed coat and root) for insecticidal activity against third instar larvae of Spodoptera litura using leaf dip bioassay method. Among the tissues screened (leaf, bark, seed, seed coat and root), the leaf extract was most effective and showed highest mortality (60%) at 5% concentration as compared to other extracts followed by seed (20%), seed coat (20%) and root (20%).

https://www.entomoljournal.com/archives/2017/vol5issue1/PartA/5-1-16-597.pdf

Bioefficacy of crude extracts from Jatropha curcas against Spodoptera litura

The indiscriminate use of chemical insecticides leads considerable damage to environment and imbalance the ecology. The continuous and overuse of chemical insecticides imparts resistance in vectors of human diseases along with agricultural pests (Georghiou, 1990). Biocontrol is the better option than chemical pesticides in order to control insect pests in insect management programme (Aramideh et al., 2010). Bacillus thuringiensis is gram positive, aerobic, endospore forming and ubiquitous in nature with genome size 2.4 to 5.7 Mbp, distinguished from other bacilli by International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 6 Number 1 (2017) pp. 798-806 Journal homepage: http://www.ijcmas.com

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Dipika A Padole

Papers

Phytochemicals: Extraction methods, identification and detection of bioactive compounds from plant extracts

Phosphate Solubilizing Microbes: An Overview

Screening of insecticidal activity of Jatropha Curcas (L.) against diamond back moth and Helicoverpa Armigera

Bioefficacy of crude extracts from Jatropha curcas against Spodoptera litura

Isolation and Characterization of Native Isolates of Bacillus thuringiensis from Vidarbha Region