Phytochemical analysis of mite-infested tea leaves of Darjeeling Hills, India.

INTRODUCTION: Darjeeling tea of India is one of the most famous beverages globally. However, a large amount of tea crop is damaged every year by the attack of mites. OBJECTIVES: The study aimed to determine the changes in different pigments and biochemical components of tea leaves due to mite infestation. MATERIALS AND METHODS: We used UV-visible and Fourier-transform infrared (FTIR) spectroscopy simultaneously to understand the damages in pigment contents of the leaves of tea (Camellia sinensis (L.) Kuntze) due to attack of phytophagus mite, Oligonychus coffeae Nietner. Furthermore, chemical analysis of infested tea leaves was also performed to compare the nutrients of the plants, namely total phenol, protein and soluble sugar. RESULTS: The UV-visible study reveals severe reduction of the pigments such as chlorophyll (Chl), carotenoids and xanthophylls in the tea leaf due to mite infestation. The findings of the FTIR study, also shows variation in different physiochemical components in the leaf Chl. The sugar and protein content of the infested leaves have been reduced compared to uninfested ones. Results in the case of tea leaves plucked during first (March) and third (November) flushes show similar trends. CONCLUSION: The increase in phenolic and alcoholic components and decrease in Chl contents may affect the quality of Darjeeling tea. The extent of damages done by the pests measured here could aid the pest management in tea gardens.

The antioxidant activity of allylpyrocatechol is mediated via decreased generation of free radicals along with escalation of antioxidant mechanisms.

Allylpyrocatechol (APC) is responsible for the antiinflammatory activity exhibited by the methanolic extract of leaves of Piper betle. As antiinflammatory compounds may display antioxidant properties and vice versa, we investigated the antioxidant effect of APC. APC effectively reduced phorbol-myristate-acetate-induced generation of reactive oxygen species and superoxide in murine peritoneal macrophages as well as inhibited Escherichia-coli-induced phagocytic activity of macrophages. Furthermore, pBluescript SK(+) plasmid DNA damage induced by addition of sodium ascorbate was attenuated by APC as it inhibited transformation of the supercoiled form to a relaxed form. In addition, APC increased the enzymatic (catalase) and nonenzymatic (GSH) antioxidant components of murine macrophages. Taken together, APC exhibited an antioxidant activity which was mediated both via decreased generation of free radicals along with increase in cellular antioxidants.

Effect of methanol extract of Bombax malabaricum leaves on nitric oxide production during inflammation.

In different parts of India, Bombax malabaricum DC. (Family: Bombacaceae), a lofty deciduous tree with large leaves, is traditionally used in inflammation. The aim of the present study was to confirm its antiinflammatory activity and to search for the possible mechanism of action for methanol extract of Bombax malabaricum leaves (MEBM). The anti-inflammatory activity of MEBM was evaluated in a carrageenan-induced model of acute inflammation. As inflammation usually involves increased nitric oxide (NO) production, effect of MEBM on lipopolysaccharide-induced NO production in mouse peritoneal macrophages was studied to evaluate its possible mechanism of action. It was found that MEBM was non-toxic up to a dose of 2 g/kg for mice and rats, orally. MEBM (100, 200, and 400 mg/kg) significantly reduced carrageenan-induced rat paw edema (p < 0.05, p < 0.01, p < 0.001, respectively). In mice peritoneal macrophages, the IC50 for MEBM was 258.33 +/- 6.96 microg/mL and it was non-toxic up to 125 microg/mL. MEBM (0-100 microg/mL) reduced lipopolysaccharide-induced NO production in macrophages in a dose-dependent fashion (p < 0.001). Hence, MEBM possesses antiinflammatory activity, mediated through inhibition of NO production.

Anti-inflammatory effect of allylpyrocatechol in LPS-induced macrophages is mediated by suppression of iNOS and COX-2 via the NF-kappaB pathway.

The crude ethanol extract of Piper betle leaf is reported to possess anti-inflammatory activity which has been suggested to be mediated by allylpyrocatechol (APC). In the present study, we have demonstrated the anti-inflammatory effects of APC (10 mg/kg, p.o.) in an animal model of inflammation. To investigate the mechanism(s) of this anti-inflammatory activity, we examined its effects on the lipopolysaccaride (LPS)-induced production of NO and PGE(2) in a murine macrophage cell line, RAW 264.7. APC inhibited production of NO and PGE(2) in a dose dependent manner as also decreased mRNA expression of iNOS, COX-2, IL-12p40 and TNF-alpha. Since nuclear factor-kappaB (NF-kappaB) appears to play a central role in transcriptional regulation of these proteins, we investigated the effects of APC on this transcription factor. APC inhibited LPS induced nuclear factor-kappaB (NF-kappaB) activation, by preventing degradation of the inhibitor kappaB (IkappaB). Taken together, our data indicates that APC targets the inflammatory response of macrophages via inhibition of iNOS, COX-2 and IL-12 p40 through down regulation of the NF-kappaB pathway, indicating that APC may have therapeutic potential in inflammation associated disorders.

Sustained release gastroretentive tablet of metformin hydrochloride based on poly (acrylic acid)-grafted-gellan.

Development of a gastroretentive sustained release tablet of metformin based on poly (acrylic acid)-grafted-gellan (PAAc-g-GG) is the main purpose of this study. At first, PAAc-g-GG was synthesized by microwave-promoted free radical initiation method using cerric (IV) ammonium nitrate (CAN) as redox initiator and characterized by elemental analysis, FTIR, DSC-TGA, 13C NMR, biodegradation and viscosity study. The synthetic parameters were optimized by 23 full factorial design using Design Expert software. Acute oral toxicity and histological studies were also performed as per OECD guideline. Tablets were then prepared employing wet granulation method using PAAc-g-GG and evaluated for various physical characters, in vitro drug release, ex-vivo mucoadhesion and swelling. Compatibility between drug and excipients was checked by DSC and FTIR analysis. The F3 batch showed excellent mucoadhesion and sustained drug release over a period of 10h with dissolution similarity factor, f2=77.43. Kinetic modeling unveiled Case-1 Fickian diffusion based drug release mechanism.

Operons are a conserved feature of nematode genomes.

The organization of genes into operons, clusters of genes that are co-transcribed to produce polycistronic pre-mRNAs, is a trait found in a wide range of eukaryotic groups, including multiple animal phyla. Operons are present in the class Chromadorea, one of the two main nematode classes, but their distribution in the other class, the Enoplea, is not known. We have surveyed the genomes of Trichinella spiralis, Trichuris muris, and Romanomermis culicivorax and identified the first putative operons in members of the Enoplea. Consistent with the mechanism of polycistronic RNA resolution in other nematodes, the mRNAs produced by genes downstream of the first gene in the T. spiralis and T. muris operons are trans-spliced to spliced leader RNAs, and we are able to detect polycistronic RNAs derived from these operons. Importantly, a putative intercistronic region from one of these potential enoplean operons confers polycistronic processing activity when expressed as part of a chimeric operon in Caenorhabditis elegans. We find that T. spiralis genes located in operons have an increased likelihood of having operonic C. elegans homologs. However, operon structure in terms of synteny and gene content is not tightly conserved between the two taxa, consistent with models of operon evolution. We have nevertheless identified putative operons conserved between Enoplea and Chromadorea. Our data suggest that operons and "spliced leader" (SL) trans-splicing predate the radiation of the nematode phylum, an inference which is supported by the phylogenetic profile of proteins known to be involved in nematode SL trans-splicing.

Anti-inflammatory effect of a methanolic extract of leaves of Dregea volubilis.

AIM OF STUDY: The aim of this study was to establish the anti-inflammatory activity of the methanolic extract of Dregea volubilis leaves (MEDV) with its fractions and to delineate the possible mechanism of action for MEDV. MATERIALS AND METHODS: The anti-inflammatory activities of MEDV along with its petroleum ether and chloroform fractions were evaluated in a carrageenan induced model of acute inflammation. The effect of MEDV on lipopolysaccharide induced production of nitric oxide (NO) in macrophages was also studied. RESULTS: MEDV (100, 200 and 400 mg/kg body weight) significantly reduced carrageenan induced paw edema; chloroform fraction was most potent (66%, p<0.001). MEDV was non-toxic up to 125 µg/ml in mouse peritoneal macrophages wherein it (0-100 µg/ml) reduced lipopolysaccharide induced NO production. CONCLUSION: MEDV possesses significant anti-inflammatory activity. Chloroform fraction of MEDV showed best anti-inflammatory activity.

In vitro and in vivo activity of Aloe vera leaf exudate in experimental visceral leishmaniasis.

The leishmanicidal activity of Aloe vera leaf exudate (AVL) has been demonstrated in promastigotes and axenic amastigotes, but its effectiveness in animal models has not been evaluated. The presence of alkaloids, triterpenes, cyanidines, proanthocyanidines, tannins, and saponins in AVL was identified. Its effectiveness in four Leishmania donovani strains was studied both in promastigotes (IC50 ranged from 70-115 microg/ml) and amastigotes (IC50 ranged from 3.1-11.4 microg/ml). In amastigotes, the killing by AVL was facilitated through its induction of nitric oxide in leishmania-infected macrophages. The safety index was good as AVL up to 300 microg/ml remained non-toxic to monocytes and macrophages. In a L. donovani BALB/c mouse model, oral or subcutaneous administration of AVL (15 mg/kg body weight x 5 days) reduced parasitemia by >90% in the liver, spleen, and bone marrow without impairment of hepatic and renal functions. Collectively, we conclude that AVL shows promising antileishmanial activity and may provide a new lead agent in the treatment of Leishmaniasis.