P. S. Pavithra

Bio: P. S. Pavithra is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Antibacterial activity & Minimum bactericidal concentration. The author has an hindex of 4, co-authored 5 publications receiving 168 citations.

Antibacterial activity of plants used in Indian herbal medicine

Abstract: Delonix elata, Enicostemma axillare, Merremia tridentata, Mollugo cerviana and Solanum incanum are medicinal plants used in traditional Indian medicine for the treatment of various ailments. These plants were selected to evaluate their potential antibacterial activity. To determine antibacterial activity and phytochemicals in the crude extracts of five medicinal plants used in traditional Indian medicine for the treatment of various ailments like rheumatism, piles fever, skin diseases and snake bite. The antibacterial activity of organic solvent extracts of these plants were determined by disc diffusion and broth dilution techniques against grampositive bacterial strains (Bacillus subtilis, Staphylococcus aureus) and gram-negative bacterial strains (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa). Results revealed that the chloroform and methanol extracts of D. elata and methanol extracts of M. cerviana exhibited significant antibacterial activity against gram-positive and gram-negative strains with minimum bactericidal concentration (MBC) ranging from 1.5 to 100 mg/ml. Methanol extracts of M. tridentata exhibited activity only against gram-positive bacterial strains with MBC ranging from 12.5 to 100 mg/ml. Extracts of E. axillare and S. incanum showed activity only against B. subtilis and were not bactericidal at 100 mg/ml. The most susceptible organism to the organic extracts from all the studied plants was B. subtilis and the most resistant organism was P. aeruginosa. The presence of phytochemicals such as alkaloids, tannins, triterpenoids, steroids and glycosides in the extracts of these plants supports their traditional uses as medicinal plants for the treatment of various ailments. The present study reveals potential use of these plants for developing new antibacterial compounds against pathogenic microorganisms. Key words: Antibacterial, Enicostemma axillare, Merremia tridentata, Mollugo cerviana, Solanum incanum

Antibacterial and antioxidant activity of methanol extract of Evolvulus nummularius.

Abstract: Objective : To evaluate the antibacterial and antioxidant activity of methanol extract of Evolvulus nummularius (L) L. Materials and Methods : Disc diffusion and broth serial dilution tests were used to determine the antibacterial activity of the methanol extract against two Gram-positive bacterial strains (Bacillus subtilus NCIM 2718, Staphylococcus aureus ATCC 25923) and three Gram-negative bacterial strains (Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 and Escherichia coli ATCC 25922). The methanol extract was subjected to preliminary phytochemical analysis. Free radical scavenging activity of the methanol extract at different concentrations was determined with 2, 2-diphenyl-1picrylhydrazyl (DPPH). Results : The susceptible organisms to the methanol extract were Escherichia coli (MIC=12.50 mg/ml) and Bacillus subtilus (MIC=3.125 mg/ml) and the most resistant strains were Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa. The methanol extracts exhibited radical scavenging activity with IC50 of 350 μg/ml. Conclusion : The results from the study show that methanol extract of E.nummularius has antibacterial activity. The antioxidant activity may be attributed to the presence of tannins, flavonoids and triterpenoids in the methanol extract. The antibacterial and antioxidant activity exhibited by the methanol extract can be corroborated to the usage of this plant in Indian folk medicine.

Phytochemicals: Extraction, Isolation, and Identification of Bioactive Compounds from Plant Extracts

Abstract: There are concerns about using synthetic phenolic antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) as food additives because of the reported negative effects on human health. Thus, a replacement of these synthetics by antioxidant extractions from various foods has been proposed. More than 8000 different phenolic compounds have been characterized; fruits and vegetables are the prime sources of natural antioxidants. In order to extract, measure, and identify bioactive compounds from a wide variety of fruits and vegetables, researchers use multiple techniques and methods. This review includes a brief description of a wide range of different assays. The antioxidant, antimicrobial, and anticancer properties of phenolic natural products from fruits and vegetables are also discussed.

A review on recent research results (2008–2010) on essential oils as antimicrobials and antifungals. A review.

Abstract: The antimicrobial activity of essential oils is discussed in this review taking in account studies which were published in the period of time from 2008 until September 2010. Furthermore, the most important methods to examine the antimicrobial efficiency of essential oils are presented. The studies are divided into the following two groups, namely antibacterial and antifungal active agents depending on the activity of the applied essential oil against the test microorganisms. Various interesting possible applications are revealed such as the use of essential oils instead of synthetic drugs to circumvent the increasing resistance of some pathogens. Moreover, they could not only be used for the therapy of infectious illnesses, but also as preservatives in the food industry. A further possibility is, among others, the application of essential oils in skin products in order to treat or avoid dermal infections. Additionally, the prevalent constituents of the individual antimicrobial active essential oils are elaborated. Copyright © 2011 John Wiley & Sons, Ltd.

Traditional herbal medicine in Far-west Nepal: a pharmacological appraisal

Abstract: Plant species have long been used as principal ingredients of traditional medicine in far-west Nepal. The medicinal plants with ethnomedicinal values are currently being screened for their therapeutic potential but their data and information are inadequately compared and analyzed with the Ayurveda and the phytochemical findings. The present study evaluated ethnomedicinal plants and their uses following literature review, comparison, field observations, and analysis. Comparison was made against earlier standard literature of medicinal plants and ethnomedicine of the same area, the common uses of the Ayurveda and the latest common phytochemical findings. The field study for primary data collection was carried out from 2006-2008. The herbal medicine in far-west Nepal is the basis of treatment of most illness through traditional knowledge. The medicine is made available via ancient, natural health care practices such as tribal lore, home herbal remedy, and the Baidhya, Ayurveda and Amchi systems. The traditional herbal medicine has not only survived but also thrived in the trans-cultural environment with its intermixture of ethnic traditions and beliefs. The present assessment showed that traditional herbal medicine has flourished in rural areas where modern medicine is parsimoniously accessed because of the high cost and long travel time to health center. Of the 48 Nepalese medicinal plants assessed in the present communication, about half of the species showed affinity with the common uses of the Ayurveda, earlier studies and the latest phytochemical findings. The folk uses of Acacia catechu for cold and cough, Aconitum spicatum as an analgesic, Aesculus indica for joint pain, Andrographis paniculata for fever, Anisomeles indica for urinary affections, Azadirachta indica for fever, Euphorbia hirta for asthma, Taxus wallichiana for tumor control, and Tinospora sinensis for diabetes are consistent with the latest pharmacological findings, common Ayurvedic and earlier uses. Although traditional herbal medicine is only a primary means of health care in far-west Nepal, the medicine has been pursued indigenously with complementing pharmacology and the Ayurveda. Therefore, further pharmacological evaluation of traditional herbal medicine deserves more attention.

New Trends in Cosmetics: By-Products of Plant Origin and Their Potential Use as Cosmetic Active Ingredients

Abstract: In recent years, the amount of waste deriving from industrial processes has increased substantially. Many industries produce different types of disposable by-products, rich in valuable compounds. Their characterization and valorization could not only convert them into high value products with application in diverse biotechnological fields, such as Pharmaceutics, Food or Cosmetics, but would also reduce the waste environmental impact and the related treatment costs. There are many examples of cosmetic active ingredients deriving from fish, meat and dairy products, but in the present review we would like to focus on the potentialities and the current use of compounds and extracts deriving from agronomical disposable wastes in the cosmetic field. These types of products are effective, inexpensive and bio-sustainable, and thus represent a valid alternative to the regular plant derived extracts, more commonly adopted in cosmetic formulations. Moreover, if the waste products come from organic farming, they are certainly an even more valuable source of safe extracts for Cosmetics, since they lack any residual pesticide or potentially toxic chemical.