The Preparation of Ternary Solid Dispersions of an Herbal Drug via Spray Drying of Liquid Feed

The present study aimed the preparation and characterization of ternary solid dispersions by direct spray drying of a liquid suspension containing curcumin, a solubility enhancer and a drying aid. The experiments followed a Box-Behnken design in order to evaluate the influence of temperature, ratio of curcumin: lipidic carrier, and the collodial silicon dioxide content on the characteristics of the microparticulated solid dispersions. The angle of repose, Hausner factor, Carr index, water activity, and solubility were used to characterize solid dispersions. The results show that water activity, Hausner factor, and Carr index varied in an acceptable range for pharmaceutical purposes. The condition that maximizes solubility was determined using an exploratory design based on a surface response analysis and allowed a 3200-fold increase in curcumin solubility. Ternary solid dispersion showed a 90% curcumin release after 10min during a dissolution test. The results show that the spray drying of a liquid feed is an attractive and promising alternative to obtain enhanced solubility drug ternary solid dispersions.

DRYING OF HERBAL EXTRACT IN A DRAFT-TUBE SPOUTED BED

This work evaluates the feasibility of the draft-tube spouted bed for drying of herbal extract. Drying runs were carried out according to a central composite design in a conical-cylindrical draft-tube spouted bed. The variables studied were the percentage of the drying aid (ADJ), the drying gas flow rate relative to gas flow at minimum spouting (Q/Q(ms)), and the flow rate of extract fed to the system relative to the spouting gas flow rate W(s)/W(g)). Colloidal silicon dioxide was the drying aid used in order to improve drying performance. Statistical analysis of the effects of processing parameters on product recovery, product accumulation in the bed, and product properties permitted the identification of parameters presenting significant effects on drying. Optimized drying conditions were related to experimental parameters as follow: high levels of the percentage of drying adjuvant (ADJ), high airflow rate relative to minimum spouting (Q/Q(ms)), and low values of the feed flow rate of the extract relative to the gas flow rate (W(s)/W(g)).

SOLID STATE STUDIES ON MOLECULAR INCLUSIONS OF LIPPIA SIDOIDES ESSENTIAL OIL OBTAINED BY SPRAY DRYING

Inclusion complexes of Lippia sidoides essential oil and beta-cyclodextrin were obtained by slurry method and its solid powdered form was prepared using spray drying. The influence of the spray drying, as well as the different essential oil:beta-cyclodextrin ratio on the characteristics of the final product was investigated. With regard to the total oil retention 1:10 mass/mass ratio as optimal was found between the essential oil and beta-cyclodextrin. Thermoanalytical techniques (TG, EGD, TG-MS) were used to support the formation of inclusion complex and to examine their physicochemical properties after accelerated storage conditions. It may be assumed that the thermal properties of the complexes were influenced not only by the different essential oil/beta-cyclodextrin ratio but also by the storage conditions. In the aspect of their thermal stabilities, complex prepared with 1:10 m/m ratio (essential oil: beta-cyclodextrin) was the most stable one.

Lipase Production by Endophytic Fungus Cercospora kikuchii: Stability of Enzymatic Activity after Spray Drying in the Presence of Carbohydrates

The present work deals with improving the production and stabilization of lipases from Cercospora kikuchii. Maximum enzyme production (9.384 U/ml) was obtained after 6 days in a medium supplemented with 2% soybean oil. The lipases were spray dried with different adjuvants, and their stability was studied. The residual enzyme activity after drying with 10% (w/v) of lactose, b- cyclodextrin, maltodextrin, mannitol, gum arabic, and trehalose ranged from 63 to 100%. The enzyme activity was lost in the absence of adjuvants. Most of the adjuvants used kept up at least 50% of the enzymatic activity at 5 degrees C and 40% at 25 degrees C after 8 months. The lipase dried with 10% of beta-cyclodextrin retained 72% of activity at 5 degrees C. Lipases were separated by butyl-sepharose column into 4 pools, and pool 4 was partially purified (33.1%; 269.5 U/mg protein). This pool was also spray dried in maltodextrin DE10, and it maintained 100% of activity.

Thesis summary: Standardized dried extracts of Brazilian medicinal plants: Assessment of technical and economic feasibility of spouted bed drying

This study is an integral part of a research project which seeks the establishment of protocols for the production of standardized herbal dried extracts emphasizing the spouted bed drying. This thesis was conducted at faculty of Pharmaceutical Science of Ribeiro Preto/University of So Paulo, Brazil, under supervision of Prof. Dr. Wanderley Pereira Oliveira*, defended on September 28, 2007.

Friedmanniella spumicola sp nov and Friedmanniella capsulata sp nov from activated sludge foam: Gram-positive cocci that grow in aggregates of repeating groups of cocci

Two Gram-positive, non-motile, non-spore-forming, strictly aerobic, pigmented cocci, strains Ben 107(T) and Ben 108(T), growing in aggregates were isolated from activated sludge samples by micromanipulation. Both possessed the rare type A3 gamma' peptidoglycan. Major menaquinones of strain Ben 107(T) were MK-9(H-4) and MK-7(H-2), and the main cellular fatty acid was 12-methyltetradecanoic acid (ai-C-15:0). In strain Ben 108(T), MK-9(H-4), MK-9(H-2) and MK-7(H-4) were the menaquinones and again the main fatty acid was 12-methyltetradecanoic acid (ai-C-15:0). Polar lipids in both strains consisted of phosphatidyl inositol, phosphatidyl glycerol and diphosphatidyl glycerol with two other unidentified glycolipids and phospholipids also present in both. These data, together with the 16S rDNA sequence data, suggest that strain Ben 107(T) belongs to the genus Friedmanniella which presently includes a single recently described species, Friedmanniella antarctica. Although the taxonomic status of strain Ben 108(T) is far less certain, on the basis of its 16S rRNA sequence it is also adjudged to be best placed in the genus Friedmanniella, The chemotaxonomic characteristics and DNA-DNA hybridization data support the view that Ben 107(T) and Ben 108(T) are novel species of the genus Friedmanniella. Hence, it is proposed that strain Ben 107(T) (=ACM 5121(T)) is named as Friedmanniella spumicola sp. nov. and strain Ben 108(T) (=ACM 5120(T)) as Friedmanniella capsulata sp. nov.

Physical properties and fluidization behaviour of fresh green bean particulates during fluidized bed drying

Changes in the physical properties (such as particle density, bulk density of the bed, shrinkage and bed porosity) of fresh green bean particulates were investigated during drying. Three length:diameter ratios (1:1, 2:1 and 3:1) were considered, using drying conditions of 50 +/- 2 degrees C and 13 +/- 2% relative humidity in a heat pump dehumidifier system. The fluidization behaviour was also evaluated at 10 levels of moisture content. The fluidization experiments demonstrated that the minimum fluidization velocity decreases as the drying proceeds due to the reduced moisture content and changes in the physical properties of the bean particulates. Empirical relationships of the following nature were developed for the change in shrinkage [VR = 1 - Be-kMR], particle density [rho(p) = A + BMR + C (exp)(-D MR)], bulk density [rho(b) = a(1) + b(1)MR + c(1)MR(2)] and bed porosity [epsilon = a(2) + b(2)MR + c(2)MR(2)] with the moisture content during fluidized bed drying.

Europium luminescent polymeric microspheres fabricated by spray drying process

The spray drying method was used to prepare luminescent microspheres. These microspheres were prepared by spraying an aqueous solution of dextrin and an europium(III) complex with subsequent drying in a hot medium. The spray dried powder was characterized by scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). Particle size distribution was estimated from SEM images. The ultrasonic spray drying technique was successfully applied to yield a microparticulated and red luminescent powder composed by the [Eu(dpa)(3)](3-) stop (dpa = dipicolinic acid) complex incorporated in dextrin microspheres.

Early Changes in Postprandial Gallbladder Emptying in Morbidly Obese Patients Undergoing Roux-en-Y Gastric Bypass: Correlation with the Occurrence of Biliary Sludge and Gallstones

Gallstones have been frequently diagnosed after Roux-en-Y gastric bypass (RYGBP). Gallbladder stasis associated with duodenal exclusion may play a role in their pathogenesis. Gallbladder emptying was studied before and on the 30th and 31st postoperative days (POD) after RYGBP in 20 morbidly obese patients. Gallbladder volume after fasting and every 15 min during a 2-h period following administration of a standard liquid meal was determined by sonography. On the 31st POD, the meal was administered through the gastrostomy in order to promote its transit through the duodenum. Fasting volume (FV), maximum ejection fraction (Max EF), and residual volume (RV) were determined. Biliary sludge and calculi were investigated after 1 and 6 months, respectively. FV was 39.4 +/- 20.2 ml, 50.1 +/- 22.7 ml, and 47.9 +/- 23.4 ml, respectively, for the preoperative and two postoperative assessments (P = 0.09). RV was 7.6 +/- 8.7 ml, 25.1 +/- 20.0 ml, and 24.6 +/- 20.9 ml; and Max EF was 80.5 +/- 20.9%, 54.3 +/- 21.4%, and 50.5 +/- 29.0%, respectively, for the pre-, postoral, and postgastrostomy infusion measurements. There was only a significant difference between the preoperative value and the two postoperative values (P < 0.001). Biliary sludge was detected in 65% of the patients and 46% of them subsequently developed gallstones. Gallbladder emptying became significantly compromised after RYGBP. This impairment was unrelated to duodenal exclusion but it was associated with biliary sludge and stone formation.

Problems associated with spray drying of sugar-rich foods

Stickiness is a major reason that limits the spray drying of various sugar-rich food products. Higher hygroscopicity of amorphous powder, increase in solubility of sugars with temperature, and lower melting point and glass transition temperature, contribute to the stickiness problem. So far, the glass transition temperature has been widely accepted as a best indicator for stickiness. There are various manoeuvres that have been applied to spray dry such products. Some of them are the addition of drying aids, modification of drier design and use of mild drying temperature conditions. This review paper highlights the major research works that deal with the stickiness property of sugar-rich foods.

A semi-empirical approach to optimise the quantity of drying aids required to spray dry sugar-rich foods

A semi-empirical linear equation has been developed to optimise the amount of maltodextrin additive (DE 6) required to successfully spray dry a sugar-rich product on the basis of its composition. Based on spray drying experiments, drying index values for individual sugars (sucrose, glucose, frutose) and citric acid were determined, and us;ng these index values an equation for model mixtures of these components was established. This equation has been tested with two sugar-rich natural products, pineapple juice and honey. The relationship was found to be valid for these products.

Effects of process modification and heat pump drying on physical and sensory properties of Chinese style shredded beef

Chinese-style dried, shredded meat is traditionally prepared by sequential cooking, shredding, pre-drying, and final drying (roasting) of lean meat. In this study, shredded dried beef (a(w)<0.6) was prepared by omitting roasting but prolonging pre-drying. Sensory scores of the modified product were lower than those for the traditional product. When heat pump drying replaced traditional oven drying, drying time was shortened without significant difference in quality attributes. Desorption curves were established for shredded beef at several drying temperatures.

Evaluation of the genotoxicity of treated urban sludge in the Tradescantia micronucleus assay

The sludge produced in sewage treatment plants can contain toxic substances. Among these, the genotoxic substances are of great concern. The present paper aimed at evaluating the genotoxicity of treated sludge samples collected at four different sewage treatment plants (STP) located in the State of Sao Paulo Brazil, using the Trad-MN assay. Another objective of the study was to compare the responses of the Clone #4430 with the Tradescantia pallida. Sludge samples mixed with reference soil in concentrations of 10, 25 and 50% (v/v) were tested in experiments with 3 months exposure in the field. Negative and positive controls (arsenic trioxide) were also tested with both plants. In Clone #4430 two sludge samples induced genotoxicity while in T pallida three were positive, although no clear dose-response were observed for both plants. Results with the negative and positive controls suggest that T pallida presented similar results when compared to the Clone #4430. The protocol using plants chronically exposed to sludge mixed with soil seems to be a promising tool to assess the genotoxicity of sludge although time consuming. (C) 2008 Elsevier B.V. All rights reserved.