Microencapsulate Aspergillus niger peptidases from agroindustrial waste wheat bran: spray process evaluation and stability.

The aim of this work was to obtain microencapsulated stable Aspergillus niger peptidases by post fermentation spray drying. The enzymatic extract was evaluated before and after spray drying microencapsulation to verify the effects of five different process parameters on the extract enzymatic activity, i.e. air flow, extract feed rate, drying temperature, homogenising time and weight ratio of extract to encapsulation material. The optimal conditions were determined by desirability functions and experimentally confirmed. Additionally, the stability of the microparticles was assessed during 60 days at 4 °C, 25 °C and 40 °C. The results revealed that the microparticles stored at 4 °C retained approximately 100% of their proteolytic activity at nine days of storage. Considering the industrial adaptation of the bioprocess and the prospect of commercial application of the proteases, the evaluation of different parameters for drying enzymes is required as a valuable alternative to obtain biotechnological products with high added value.

Microparticles Containing Curcumin Solid Dispersion: Stability, Bioavailability and Anti-Inflammatory Activity.

This work aimed at improving the solubility of curcumin by the preparation of spray-dried ternary solid dispersions containing Gelucire®50/13-Aerosil® and quantifying the resulting in vivo oral bioavailability and anti-inflammatory activity. The solid dispersion containing 40% of curcumin was characterised by calorimetry, infrared spectroscopy and X-ray powder diffraction. The solubility and dissolution rate of curcumin in aqueous HCl or phosphate buffer improved up to 3600- and 7.3-fold, respectively. Accelerated stability test demonstrated that the solid dispersion was stable for 9 months. The pharmacokinetic study showed a 5.5-fold increase in curcumin in rat blood plasma when compared to unprocessed curcumin. The solid dispersion also provided enhanced anti-inflammatory activity in rat paw oedema. Finally, the solid dispersion proposed here is a promising way to enhance curcumin bioavailability at an industrial pharmaceutical perspective, since its preparation applies the spray drying, which is an easy to scale up technique. The findings herein stimulate further in vivo evaluations and clinical tests as a cancer and Alzheimer chemoprevention agent.

Spray-dried propolis extract, II: prenylated components of green propolis.

The effect of spray drying conditions on the chemical composition of Brazilian green propolis extract was investigated using a factorial design and high performance liquid chromatography. The raw and dried extract contents of caffeic acid, p-coumaric acid, drupanin, isosakuranetin, artepillin C, baccharin and 2,2-dimethyl-6-carboxyethenyl-2H-1-benzopyran were quantified using veratraldehyde (3,4-dimethoxybenzaldehyde) as internal standard. The baccharin content in spray-dried propolis was affected by the drying temperature with a 5% significance level, while the coumaric acid and drupanin contents were dependent on drying temperature at a 15% significance level. The other chemical markers, caffeic acid, isosakuranetin, artepillin C and 2,2-dimethyl-6-carboxyethenyl-2H-1-benzopyran, showed to be independent of drying conditions. However, all the chemical markers showed some loss on drying, which varied from 30 to 50%. The results showed that prenylated compounds are sensitive to drying, but their losses may be considerably reduced under low temperatures, around 40 degrees C. The antioxidant activity of the spray dried propolis was determined by the diphenylpicrylhydrazyl (DPPH) method and showed a quadratic dependency on the temperature; extract feed rate and the interaction between them. However, spray dried propolis extracts presented antioxidant activities similar to the original propolis tincturae.

Spray-dried propolis extract. I: physicochemical and antioxidant properties.

The effect of spray drying on the chemical and biological properties of alcoholic extract of green propolis was investigated. The total polyphenol and flavonoid contents in spray-dried propolis extract were determined by the Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. The antioxidant activity of the dry extract was assessed by the membrane lipid peroxidation inhibition method, using quercetin as reference. The polyphenol content was shown to depend on the drying air outlet temperature and its square at the 0.5% significance level, while the flavonoid content depended only on the square of the outlet temperature at the 5% significance level. Polyphenol and flavonoid recovery after spray-drying ranged from 45.1 to 54.9% and 30.6 to 40.8%, respectively. The antioxidant activity of the spray-dried propolis was shown to be affected by the extract feed rate and air outlet temperature at a significance level of 0.1%. The spray-dried propolis extract showed significant antioxidant activity, with 50% lipid peroxidation inhibition at concentrations ranging from 2.5 to 5.0 microg/ml.