Synergistic effect of bacterial cellulose reinforcement and succinic acid crosslinking on the properties of agar.

In this work, the modification of agar is presented with the synergistic effect of bacterial cellulose reinforcement and succinic acid crosslinked agar. The effect of crosslinking agar with succinic acid on tensile strength and water absorption were studied. Crosslinking was confirmed with Fourier infrared spectroscopy. The tensile strength of agar was increased by 70% by succinic acid crosslinking (from55 ± 9.97 MPa to 93.40 ± 9.97 MPa) and the crosslinked agar absorbed only 18.66% water compared to uncrosslinked agar. The tensile strength of agar was increased by 56% by bacterial cellulose reinforcement (55 ± 9.97 MPa to 86.30 ± 14.70 MPa). The strength of agar was improved by 101% by the synergistic effect of bacterial cellulose reinforcement and succinic acid crosslinking (55 ± 9.97 MPa to 111 ± 12.30 MPa). Cytocompatibility studies of the developed films suggested that the crosslinked samples can also have potential applications in biomedical engineering apart from packaging applications.

Crosslinking of agar by diisocyanates.

In the present study, crosslinking of agar using diisocyanate (DI) was demonstrated to limit the high water absorption property of agar. In addition, the efficacy of aromatic diisocyanate, DDI (4, 4 diphenyl diisocyanate) and aliphatic diisocyanate, HDI (1, 6 hexamethylene diisocyanate) on crosslinked agar properties was compared. The water uptake was successfully reduced by crosslinking and its minimum values observed for DDI and HDI crosslinked agar was 33.6% and 43.6%, respectively in comparison to agar (206%). The maximum tensile strength was observed for DDI crosslinked agar (45.3 MPa) which was higher than HDI crosslinked agar (30.6 MPa) and agar (31.7 MPa). The aromatic diisocyanates crosslinked agar showed better thermal resistance at higher temperature. It was observed that aromatic diisocyanate crosslinked agar more effectively than the aliphatic diisocyanate due to the higher reactivity. The crosslinked agar samples were hemocompatible and show non-toxic nature for cell proliferation.

Agarose bioplastic-based drug delivery system for surgical and wound dressings.

We have developed an agarose-based biocompatible drug delivery vehicle. The vehicle is in the form of thin, transparent, strong and flexible films. The biocompatibility and haemocompatibility of the films is confirmed using direct and indirect contact biological assay. Contact angle measurement exhibits hydrophilic nature of the films, and protein adsorption test shows low protein adsorption on the film surface. Drugs, antibiotics and antiseptics, retain their potency after their incorporation into the films. Our bioplastic films can be a versatile medium for drug delivery applications, especially as wound and surgical dressings where a fast drug release rate is desired.

Biological Evaluation of Pupalia lappacea for Antidiabetic, Antiadipogenic, and Hypolipidemic Activity Both In Vitro and In Vivo.

Objective. The present study assesses the effect of Pupalia lappacea (L.) Juss. (Amaranthaceae) (PL) leaves ethanolic extract on adipocytes, blood glucose level, and lipid level in streptozotocin (STZ) induced diabetic rats. Materials and Methods. Male Albino rats were rendered diabetic by a single moderately sized dose of STZ (45 mg/kg, intraperitoneally) at once before starting the treatment. Animals were divided into five groups: normoglycemic control, diabetic control, reference group (glibenclamide, 5.0 mg/kg), AS001 (250 mg/kg extract), and AS002 (500 mg/kg extract) each containing six animals for in vivo study. Antidiabetic and hypolipidemic activity of extract were determined by in vivo method on STZ induced diabetic rats. Antiadipogenic activity was determined by in vitro method on 3T3-L1 cell line in comparison to simvastatin as reference drug. Result. The extract showed significant fall in fasting serum glucose (FSG), that is, 234.68 and 211.61 mg/dL, in STZ induced diabetic animals for dose groups AS001 and AS002, respectively. The PL extract also exhibited noteworthy antiadipogenic activity on 3T3-L1 cell line. The value of inhibitory concentration (IC50) of PL extract to reduce adipocyte cells was found to be 662.14 µg/mL. Conclusion. The PL extract exhibited significant antiadipogenic, antidiabetic, and hypolipidemic activities.

In-vitro and in-vivo antiadipogenic, hypolipidemic and antidiabetic activity of Diospyros melanoxylon (Roxb).

ETHNOPHARMACOLOGICAL RELEVANCE: The plant Diospyros melanoxylon (Roxb) belongs to the family Ebenaceae that is native to India and Sri-lanka. This is a medium-sized tree, reaching a height of 15 m and is well known for its beedi making leaves throughout the world. The purpose of the present study is to assess the effect of Diospyros melanoxylon leaves petroleum ether extract on blood glucose level, lipid level, insulin level, body weight, water and food intake in Streptozotocin (STZ) induced diabetic rats. MATERIALS AND METHODS: Two different doses of extract AK001 (250 mg/kg) and AK002 (500 mg/kg) of Diospyros melanoxylon leaves were taken to evaluate different activities. The animals were divided into five groups namely normal control, diabetic control, reference group, AK001 and AK002 each containing six animals for in-vivo study. In-vitro study for antiadipogen activity was performed on 3T3-L1 cell line. RESULTS: The extract showed dose dependent fall in Fasting Glucose Level (FSG) in experimental diabetic animals with significant reduction in food and water intake and increase in body weight. The extract exhibited hypocholesterolemic and hypotriglyceridemic effects while increased level of HDL in diabetes induced rats. In-vitro activity showed more than 75% viability of cells and significant inhibition in differentiated cells as compared to non-differentiate cells in 3T3-L1 cell line. The extract exhibited the concentration-dependent inhibitory effect with an IC50 value of 689.22 µg/ml. CONCLUSIONS: The extract exhibited significant results for antiadipogenic, antidiabetic and hypolipidemic activity both in-vivo and in-vitro and it may prove to be effective for the treatment of both types of diabetes, i.e. Insulin Dependent Diabetes Mellitus (IDDM) and Noninsulin Dependent Diabetes Mellitus (NIDDM).