Methanolic Extract of Plumbago Zeylanica - A Remarkable Antibacterial Agent Against Many Human and Agricultural Pathogens.

OBJECTIVES: The current investigation was carried out to determine the cytotoxic and the antimicrobial activities of methanolic extracts of Plumbago zeylanica. METHODS: The stems, leaves, and whole plants were air dried and extracted with methanol by using a Soxhlet extractor for 72 hours at 55 - 60°C. The antimicrobial activities were determined from the zones of inhibition, which were measured by using the agar well diffusion method, and the cytotoxicity assays were performed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method. RESULTS: The methanolic extracts of the stem and the leaves of Plumbago zeylanica were tested against six bacterial species and nine fungal species, and both extracts showed antimicrobial activity in a dose-dependent manner. The leaf extract of Plumbago zeylanica showed maximum antimicrobial activity against both Staphylococcus aureus sub sp aureus and Fusarium oxysporum. The stem extract was found to be more antimicrobial against the Pseudomonas aeruginosa and the Penicillium expansum species. MTT assays were used to test the cytotoxicity of the whole plant extract in the HCT-116 and the K-562 cell lines, and that extract was shown to have weak cytotoxicity in both cell lines. CONCLUSION: In the present study, the methanolic stem extracts of Plumbago zeylanica were found to possess remarkable antibacterial activities against many human and agricultural pathogens. The extracts were also found to possess significant antifungal activities, but the antifungal activities were less than the antibacterial activities. Finally, the extracts were found to have weak cytotoxicities in the HCT-116 and the K-562 cell lines.

Effect of Ca+2 ion on the release of diltiazem hydrochloride from matrix tablets of carboxymethyl xanthan gum graft polyacrylamide.

The effect of Ca2+ ion cross-linker on acryalamide grafted carboxymethyl xanthan gum (CMXG-g-PAAm) on the drug release was investigated. Previously, CMXG was synthesized from XG and further grafted to CMXG-g-PAAm to retard the drug release. Once the CaCl2 solution is added to CMXG-g-PAAm, Ca2+ considerably affected the drug release mechanism mainly by diffusion and erosion. In order to validate the grafted polymer, tablets were prepared using wet granulation and dry granulation methods It has been noticed that the tablets prepared by wet granulation successfully controls the release of the drug over an extended period of time. Moreover, the release profile was aligned to Korsmeyer-Peppas equation and exhibited the drug transport mechanism via diffusion and erosion.

Orthosiphon pallidus, a Potential Treatment for Patients with Breast Cancer.

OBJECTIVE: Orthosiphon pallidus (O. pallidus), which belongs to the Lamiaceae family, is a popular garden plant that is widely used for the treatment of various diseases, such as urinary lithiasis, fever, hepatitis, cancer and jaundice. The objective of the present work was to investigate the antioxidant free-radical scavenging and the anticancer activities of O. pallidus against human breast-cancer cell lines. METHODS: The antioxidant activity of Orthosiphon pallidus aqueous extract (OPAE) was investigated using different models, such as the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the 2, 2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) models, as were the Fe+ chelation, the hydroxyl radical and superoxide radical scavenging, and total reducing power activities. The anticancer activities of the extract were determined by using the 3-(4, 5- dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) and the sulforhodamine (SRB) assays on the MCF-7 and the MDA-MB-231 cancer cell lines. RESULTS: The aqueous Orthosiphon pallidus extract showed potent activity in in-vitro models. It significantly inhibited the scavenging of hydroxyl and superoxide radicals, but induced a remarkable Fe+ chelation activity. For both cell lines, the percent cytotoxicity was found to increase steadily with increasing OPAE concentration up to 240 µg/mL. CONCLUSION: These results suggest that Orthosiphon pallidus has excellent antioxidant, antimicrobial, and anticancer activities against human breast-cancer cell lines.

Synthesis and characterisation of poly(acryalamide) grafted carboxymethyl xanthan gum copolymer.

In the present work, an unreported graft copolymer of carboxymethyl xanthan gum and acrylamide has been synthesised by free radical polymerisation in a nitrogen atmosphere using ammonium persulphate as an initiator. The optimum reaction conditions adopted for affording maximum percentage of grafting including its grafting efficiency were obtained by varying the concentration of carboxymethyl xanthan gum from 4 to 24 g dm(-3); ammonium persulphate from 5×10(-4) to 30×10(-4)mol dm(-3); acrylamide from 0.4 to 1.2 mol dm(-3); reaction temperature from 55 to 75°C and reaction time from 30 to 90 min. The synthesised graft copolymer has been characterised by (1)H NMR, FTIR spectroscopy, X-ray diffraction measurement, thermal analysis, viscosity measurement and scanning electron microscopy. However, grafting of acrylamide onto carboxymethyl xanthan gum backbone enhanced its thermal stability. This graft copolymer might be well exploited globally as a potential carrier for drug delivery system.

Prospects of pharmaceuticals and biopharmaceuticals loaded microparticles prepared by double emulsion technique for controlled delivery.

Several methods and techniques are potentially useful for the preparation of microparticles in the field of controlled drug delivery. The type and the size of the microparticles, the entrapment, release characteristics and stability of drug in microparticles in the formulations are dependent on the method used. One of the most common methods of preparing microparticles is the single emulsion technique. Poorly soluble, lipophilic drugs are successfully retained within the microparticles prepared by this method. However, the encapsulation of highly water soluble compounds including protein and peptides presents formidable challenges to the researchers. The successful encapsulation of such compounds requires high drug loading in the microparticles, prevention of protein and peptide degradation by the encapsulation method involved and predictable release, both rate and extent, of the drug compound from the microparticles. The above mentioned problems can be overcome by using the double emulsion technique, alternatively called as multiple emulsion technique. Aiming to achieve this various techniques have been examined to prepare stable formulations utilizing w/o/w, s/o/w, w/o/o, and s/o/o type double emulsion methods. This article reviews the current state of the art in double emulsion based technologies for the preparation of microparticles including the investigation of various classes of substances that are pharmaceutically and biopharmaceutically active.

Recent expansions in an emergent novel drug delivery technology: Emulgel.

Emulgel is an emerging topical drug delivery system to which if more effort is paid towards its formulation & development with more number of topically effective drugs it will prove a boon for derma care & cosmetology. Emulgels are either emulsion of oil in water or water in oil type, which is gelled by mixing it with gelling agent. Incorporation of emulsion into gel increases its stability & makes it a dual control release system. Due to lack of excess oily bases & insoluble excipients, it shows better drug release as compared to other topical drug delivery system. Presence of gel phase makes it a non greasy & favors good patient compliance. These reviews give knowledge about Emulgel including its properties, advantages, formulation considerations, and its recent advances in research field. All factors such as selection of gelling agent, oil agent, emulsifiers influencing the stability and efficacy of Emulgel are discussed. All justifications are described in accordance with the research work carried out by various scientists. These brief reviews on formulation method have been included. Current research works that carried out on Emulgel are also discussed and highlighted the wide utility of Emulgel in topical drug delivery system. After the vast study, it can be concluded that the Emulgels appear better & effective drug delivery system as compared to other topical drug delivery system. The comprehensive analysis of rheological and release properties will provide an insight into the potential usage of Emulgel formulation as drug delivery system.

Xanthan gum and its derivatives as a potential bio-polymeric carrier for drug delivery system.

Xanthan gum is a high molecular weight natural polysaccharide produced by fermentation process. It consists of 1, 4-linked ß-D-glucose residues, having a trisaccharide side chain attached to alternate D-glucosyl residues. Although the gum has many properties desirable for drug delivery, its practical use is mainly confined to the unmodified forms due to slow dissolution and substantial swelling in biological fluids. Xanthan gum has been chemically modified by conventional chemical methods like carboxymethylation, and grafting such as free radical, microwave-assisted, chemoenzymatic and plasma assisted chemical grafting to alter physicochemical properties for a wide spectrum of biological applications. This article reviews various techniques utilized for modification of xanthan gum and its applications in a range of drug delivery systems.

Novel controlled release solid dispersion for the delivery of diclofenac sodium.

This study presents development and evaluation of novel sustained release system of diclofenac sodium (DS) prepared by solid dispersion (SD) technique using Eudragit E 100 (EE 100) and/or Eudragit S 100 (ES 100) as carriers. Compatibility of the drug and its crystalline nature in the SD were examined using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The drug was relatively stable, amorphous in the SD. The greater amount of EE100 or ES 100 in the SD slowed down the release rates with smaller dissolution efficiency and hence the mean dissolution time was enhanced. Moreover, combined carriers of EE 100-ES 100 exhibited more dissolution retarding effect than any of the carriers. The release of drug followed anomalous transport in artificial intestinal juice (pH 6.8).

Biodegradable IPN hydrogel beads of pectin and grafted alginate for controlled delivery of diclofenac sodium.

A novel diclofenac sodium (DS) loaded interpenetrating polymer network (IPN) beads of pectin and hydrolyzed polyacrylamide-graft-sodium alginate (PAAm-g-SA) was developed through ionotropic gelation and covalent cross-linking. The graft copolymer was synthesized by free radical polymerization under the nitrogen atmosphere followed by alkaline hydrolysis. The grafting, alkaline hydrolysis, and characterization of beads were confirmed by Fourier transforms infrared spectroscopy. The crystalline structure of drug after encapsulation into IPN beads were evaluated by differential scanning colorimetry and X-ray diffraction analyses. DS encapsulation was up to 96.45 %. The effect of hydrolyzed graft copolymer/pectin ratios and glutaraldehyde concentration on drug release in acidic and phosphate buffer solutions were investigated. The release of drug was significantly increased with increase of pH. The release of drug depends on the extent of cross-linking. The results indicated that IPN beads of hydrolyzed PAAm-g-SA and pectin could be used for sustained release of DS.

Approaches for breaking the barriers of drug permeation through transdermal drug delivery.

Transdermal drug delivery system (TDDS) utilizes the skin as executable route for drug administration but the foremost barrier against drug permeability is the stratum corneum and therefore, it limits therapeutic bioavailability of the bioactive. This review focuses on the recent advancements in the TDDS which include iontophoresis, sonophoresis, electroporation, microneedles, magnetophoresis, photomechanical waves and electron beam irradiation. These advancements are exhaustively discussed with techniques involved with their beneficial claims for different categories of bioactive. However, a lot of research has been carried out in TDDS, still the system has many pros and cons such as inconsistent drug release, prevention of burst release formulation and problems related to toxicity. In addition to that, to exploit the TDDS more efficiently scientists have worked on some combinational approaches for manufacturing TDDS viz., chemical-iontophoresis, chemical-electroporation, chemical-ultrasound, iontophoresis-ultrasound, electroporation-iontophoresis electroporation-ultrasound and pressure waves-chemicals and reported the synergistic effect of the same for safe, effective and practical use of TDDS. The present article covers all the above-mentioned aspects in detail and hence the article will assuredly serve as an enlightening tool for the visionaries working in the concerned area.

Advancement in stimuli triggered in situ gelling delivery for local and systemic route.

INTRODUCTION: Current research efforts focused on the design and evaluation of drug delivery systems that are easy to administer require decreased administration frequency, and provide sustained drug release in order to increase clinical efficacy and compliance of the patients. The gel forming smart polymeric formulations offer numerous applications resemble sustained and prolonged action in contrast to conventional drug delivery systems. AREAS COVERED: Article summarizes type of bioactive, sol-gel triggering factors, dose, rationales, and polymers involved in gelation with respect to their route of administration. A lot of work has been done with smart polymeric gelling system taking the advantage of stimuli (temperature and pH) triggered sol-gel phase-transition in the administered area that have great prospective in biomedical and pharmaceutical applications, particularly in target-specific controlled drug delivery systems. EXPERT OPINION: Although the principle of gelation is so attractive, key issues remain to be solved which include (i) variability of the drug release, (ii) avoidance of burst release in case of depot formulation, and (iii) issues related to toxicity. Unfortunately, till now area concerning the detailed processes of the gelling formation is still not much explored. Despite this proclamation, many efforts are made in industry and institutions to improve concerned approaches. New materials and approaches enter the preclinical and clinical phases and one can be sure that this strategy will gain further clinical importance within the next years. Thus, this review article will assuredly serve as an informative tool for the innovators working in the concern area.

Alginate based hydrogel as a potential biopolymeric carrier for drug delivery and cell delivery systems: present status and applications.

Alginate is a non-toxic, biocompatible and biodegradable natural polymer with a number of peculiar physicochemical properties for which it has wide applications in drug delivery and cell delivery systems. Hydrogel formation can be obtained by interactions of anionic alginates with multivalent inorganic cations by simple ionotropic gelation method. Hydrophilic polymeric network of three dimensional cross linked structures of hydrogels absorb substantial amount of water or biological fluids. Among the numerous biomaterials used for hydrogel formation alginate has been and will continue to be one of the most important biomaterial. Therefore, in view of the vast literature support, we focus in this review on alginate - based hydrogel as drug delivery and cell delivery carriers for biomedical applications. Various properties of alginates, their hydrogels and also various techniques used for preparing alginate hydrogels have been reviewed.

Synthesis, characterization and antimicrobial investigation of mechanochemically processed silver doped ZnO nanoparticles.

The application of nanomaterials has gained considerable momentum in various fields in recent years due to their high reactivity, excellent surface properties and quantum effects in the nanometer range. The properties of zinc oxide (ZnO) vary with its crystallite size or particle size and often nanocrystalline ZnO is seen to exhibit superior physical and chemical properties due to their higher surface area and modified electronic structure. ZnO nanoparticles are reported to exhibit strong bacterial inhibiting activity and silver (Ag) has been extensively used for its antimicrobial properties since ages. In this study, Ag doped ZnO nanoparticles were synthesized by mechanochemical processing in a high energy ball mill and investigated for antimicrobial activity. The nanocrystalline nature of zinc oxide was established by X-ray diffraction (XRD) studies. It is seen from the XRD data obtained from the samples, that crystallite size of the zinc oxide nanoparticles is seen to decrease with increasing Ag addition. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) data also supported the nanoparticle formation during the synthesis. The doped nanoparticles were subjected to antimicrobial investigation and found that both increase in Ag content and decrease in particle size contributed significantly towards antimicrobial efficiency. It was also observed that Ag doped ZnO nanoparticles possess enhanced antimicrobial potential than that of virgin ZnO against the studied microorganisms of Escherichia coli and Staphylococcus aureus.