CA : A Cancer Journal for Clinicians

Plants are a source of large amount of drugs comprising to different groups such as antispasmodics, emetics, anti-cancer, antimicrobials etc. A large number of the plants are claimed to possess the antibiotic properties in the traditional system and are also used extensively by the tribal people worldwide. It is now believed that nature has given the cure of every disease in one way or another. Plants have been known to relieve various diseases in Ayurveda. Therefore, the researchers today are emphasizing on evaluation and characterization of various plants and plant constituents against a number of diseases based on their traditional claims of the plants given in Ayurveda. Extraction of the bioactive plant constituents has always been a challenging task for the researchers. In this present review, an attempt has been made to give an overview of certain extractants and extraction processes with their advantages and disadvantages.

https://www.researchgate.net/file.PostFileLoader.html?id=52ecff43cf57d71b748b45c9&assetKey=AS%3A272427580362754%401441963204700

Phytochemical screening and Extraction: A Review

https://ciptaindomedica.files.wordpress.com/2011/01/antimicrobial-herb-and-spice-compounds-in-food.pdf

Antimicrobial herb and spice compounds in food.

Natural products from medicinal plants, either as pure compounds or as standardized extracts, provide unlimited opportunities for new drug leads because of the unmatched availability of chemical diversity. Due to an increasing demand for chemical diversity in screening programs, seeking therapeutic drugs from natural products, interest particularly in edible plants has grown throughout the world. Botanicals and herbal preparations for medicinal usage contain various types of bioactive compounds. The focus of this paper is on the analytical methodologies, which include the extraction, isolation and characterization of active ingredients in botanicals and herbal preparations. The common problems and key challenges in the extraction, isolation and characterization of active ingredients in botanicals and herbal preparations are discussed. As extraction is the most important step in the analysis of constituents present in botanicals and herbal preparations, the strengths and weaknesses of different extraction techniques are discussed. The analysis of bioactive compounds present in the plant extracts involving the applications of common phytochemical screening assays, chromatographic techniques such as HPLC and, TLC as well as non-chromatographic techniques such as immunoassay and Fourier Transform Infra Red (FTIR) are discussed.

/pdf/extraction-isolation-and-characterization-of-bioactive-1j6nvrmsjv.pdf

Extraction, Isolation and Characterization of Bioactive Compounds from Plants' Extracts

http://ssu.ac.ir/cms/fileadmin/user_upload/Mtahghighat/tfood/ARTICLES/koliat/Natural_products_as_antimicrobial_agents.pdf

Natural products as antimicrobial agents

The antibacterial effect of some selected Indian medicinal plants was evaluated on bacterial strains like Bacillus cereus ATCC11778, Staphylococcus aureus ATCC25923, Enterobacter aerogenes ATCC13048, Escherichia coli ATCC25922 and Klebsiella pneumoniae NCIM2719. The solvents used for the extraction of plants were water and methanol. The in vitro antibacterial activity was performed by agar disc diffusion and agar well diffusion method. The most susceptible Gram-positive bacteria was B. cereus, while the most susceptible Gram-negative bacteria was K. pneumoniae. The extracts of Abrus precatorius, Cardiospermum halicacabum and Gmelina asiatica could not inhibit any of the bacterial strains investigated. The most active antibacterial plant was Caesalpinia pulcherrima. The significant antibacterial activity of active extracts was compared with the standard antimicrobics, piperacillin (100 µg/disc) and gentamicin (10 µg/disc). The results obtained in the present study suggest that Caesalpinia pulcherrima can be used in treating diseases caused by the test organisms.

/pdf/in-vitro-antimicrobial-activity-and-phytochemical-analysis-3vhbpksvso.pdf

In vitro Antimicrobial Activity and Phytochemical Analysis of Some Indian Medicinal Plants

Nine plants were screened for potential antibacterial activity. In evaluating antibacterial activity both aqueous and organic solvents were used. The plants screened were Sapindus emarginatus, Hibiscus rosa-sinensis, Mirabilis jalapa, Rheo discolor, Nyctanthes arbortristis, Colocasia esculenta, Gracilaria corticata, Dictyota spps., and Pulicaria wightiana. Antibacterial activity was tested against 6 bacterial strains, Pseudomonas testosteroni, Staphylococcus epidermidis, Klebsiella pneumoniae, Bacillus subtilis, Proteus morganii, and Micrococcus flavus. Two methods, Agar disk diffusion and Agar ditch diffusion, were used to study the antibacterial activity of all these plants. Ps. testosteroni and K. pneumoniae were the most resistant bacterial strains. S. emarginatus showed strong activity against the tested bacterial strains. Therefore, this can be selected for further investigation to determine its therapeutic potential. Its leaf extract can also be used as a lead molecule in combating the diseases caused by the bacterial strains studied.

/pdf/antibacterial-activity-of-some-selected-indian-medicinal-4mw6vj25ha.pdf

Antibacterial Activity of Some Selected Indian Medicinal Flora

Twelve medicinal plants were screened, namely Abrus precatorius L., Caesalpinia pulcherrima Swartz., Cardiospermum halicacabum L., Casuarina equisetifolia L., Cynodon dactylon (L.) Pers., Delonix regia L., Euphorbia hirta L., Euphorbia tirucalli L., Ficus benghalensis L., Gmelina asiatica L., Santalum album L., and Tecomella undulata (Sm.) Seem, for potential antibacterial activity against 5 medically important bacterial strains, namely Bacillus subtilis ATCC6633, Staphylococcus epidermidis ATCC12228, Pseudomonas pseudoalcaligenes ATCC17440, Proteus vulgaris NCTC8313 and Salmonella typhimurium ATCC23564. The antibacterial activity of aqueous and methanol extracts was determined by agar disk diffusion and agar well diffusion method. The methanol extracts were more active than the aqueous extracts for all 12 plants studied. The plant extracts were more active against Gram-positive bacteria than against Gram-negative bacteria. The most susceptible bacteria were B. subtilis, followed by S. epidermidis, while the most resistant bacteria were P. vulgaris, followed by S. typhimurium. From the screening experiment, Caesalpinia pulcherrima Swartz. showed the best antibacterial activity; hence this plant can be further subjected to isolation of the therapeutic antimicrobials and further pharmacological evaluation.

https://journals.tubitak.gov.tr/biology/issues/biy-05-29-4/biy-29-4-3-0506-4.pdf

Efficacy of Aqueous and Methanol Extracts of Some Medicinal Plants for Potential Antibacterial Activity

The aqueous and methanol extracts of 12 plants each belonging to different families were evaluated for antibacterial activity against medically important bacteria viz. B. cereus ATCC11778 , S. epidermidids ATCC12228 , E. aerogenes ATCC13048, P. vulgaris NCTC 8313, S. typhimurium ATCC 23564. The in vitro antibacterial activity was performed by agar disc diffusion and agar well diffusion method. The aqueous extracts were inactive but methanol extracts showed some degree of antibacterial activity against the tested bacterial strains. S. typhimurium was the most resistant bacteria while B. cereus was the most susceptible bacteria. Amongst the plant species screened, methanol extract of Bauhinia variegata bark showed best antibacterial activity. (Afr. J. Biomed. Res. 10: 175 – 181)

/pdf/antibacterial-and-phytochemical-studies-on-twelve-species-of-1duf40wuah.pdf

Sumitra Chanda

Papers

In vitro Antimicrobial Activity and Phytochemical Analysis of Some Indian Medicinal Plants

Antibacterial Activity of Some Selected Indian Medicinal Flora

Efficacy of Aqueous and Methanol Extracts of Some Medicinal Plants for Potential Antibacterial Activity

Antibacterial and phytochemical studies on twelve species of Indian medicinal plants

Green synthesis of silver nanoparticles from marigold flower and its synergistic antimicrobial potential