Claudia R. F. Souza

Clove (Syzygium aromaticum): a precious spice

Clove (Syzygium aromaticum) is one of the most valuable spices that has been used for centuries as food preservative and for many medicinal purposes. Clove is native of Indonesia but nowadays is cultured in several parts of the world including Brazil in the state of Bahia. This plant represents one of the richest source of phenolic compounds such as eugenol, eugenol acetate and gallic acid and posses great potential for pharmaceutical, cosmetic, food and agricultural applications. This review includes the main studies reporting the biological activities of clove and eugenol. The antioxidant and antimicrobial activity of clove is higher than many fruits, vegetables and other spices and should deserve special attention. A new application of clove as larvicidal agent is an interesting strategy to combat dengue which is a serious health problem in Brazil and other tropical countries. Pharmacokinetics and toxicological studies were also mentioned. The different studies reviewed in this work confirm the traditional use of clove as food preservative and medicinal plant standing out the importance of this plant for different applications.

Manufacture of Standardized Dried Extracts from Medicinal Brazilian Plants

ABSTRACT This article presents a brief review of the research conducted at Laboratory of Pharmaceutical Processes of the Faculty of Pharmaceutical Sciences of Ribeirão Preto/São Paulo University, aiming to obtain standardized dried extracts from medicinal Brazilian plants. The spray and spouted-bed dryer performance and physicochemical product properties during the drying of hydro-alcoholic extracts of three plants used in the Brazilian traditional medicine, namely, Passiflora alata, Bauhinia forficata, and Maytenus ilicifolia, are evaluated comparatively.

Powder Properties and System Behavior during Spray Drying of Bauhinia forficata Link Extract

This article presents a study of the effects of the spray-drying conditions on product properties and dryer performance during manufacture of dried extracts of Bauhinia forficata. The product properties (loss on drying of the dried extract, flavonoids degradation ratio, product size distribution, bulk and loose densities, powder morphology) and the equipment performance were determined as a function of the input parameters (dryer inlet temperature, ratio between the feed flow rate of the extract to the dryer evaporation capacity, and feed flow rate of the drying gas). Regression equations correlating powder characteristics and dryer behavior to input process parameters were obtained. The results demonstrate significant impact of the processing conditions on product properties and dryer performance. The loss on drying is a key property, since low values are demanded for the acceptance of the dried extract. In general, due to strict product specifications, the drying conditions that give an end product with the required quality are not associated with the optimal drying performance.

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, β-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°C and 40% at 25°C after 8 months. The lipase dried with 10% of β-cyclodextrin retained 72% of activity at 5°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.

Bioactive compounds in Bidens pilosa L. populations: a key step in the standardization of phytopharmaceutical preparations

The total flavonoid content (TFC), total polyphenols content (TPC), and in vitro antioxidant activity (AA) of six Bidens pilosa L., Asteraceae, populations harvested from different localities were evaluated in this work. The plants were separated in roots, stems, and leaves/flowers, and the influence of extraction methods was investigated.Areversed-phase high-performance liquid chromatography method (HPLC) was developed and employed to obtain characteristic HPLC fingerprints of the bioactive compounds present in the extractive solutions, which were correlated with the TFC, TPC, and AA. Extractive solutions of leaves/flowers presented a higher AA when compared with those obtained from other parts of the plant (IC50 of 35.35±0.10 µg/mL). The stem extracts presented the lowest AA (IC50 117.2±1.96 µg/mL). A direct correlation of AA with TFC and TPC was evidenced. The highest AA was obtained by dynamic maceration and was statistically different from the AA presented by the extractive solutions obtained by other extraction methods. The results of this work evidenced differences that can be found at different stages of development of phytopharmaceutical preparations from B. pilosa and highlighted the importance of using the concentration of marker compounds as well as HPLC fingerprints as quality control parameters.

Stabilization of Endophytic Fungus Cercospora kikuchii Lipase by Spray Drying in the Presence of Maltodextrin and β-Cyclodextrin

In this study the effects of spray-drying conditions on the retention of enzyme activity of lipase produced by the endophytic fungus Cercospora kikuchii have been investigated. Drying runs were carried out in a bench-top spray dryer with a concurrent flow regime. The influence of the variables inlet temperature of drying gas, Tgi (86.4 to 153.6°C); mass flow rate of the enzymatic extract fed to the dryer, Ws (2.63 to 9.36 g/min); and concentration of the drying adjuvant added to the extract, ADJ (1.95 to 12.05%), on the spray-drying performance and on product quality was evaluated through experimental planning and regression analysis. The use of maltodextrin, as a stabilizing agent, slightly improved the retention of enzyme activity compared to β-cyclodextrin. Statistical optimization of the experimental results allowed the determination of the processing conditions that maximized the retention of the enzymatic activity (RAE), namely, concentration of drying adjuvants of 12.05%, inlet temperature of the drying gas of 153.6°C, and flow rate of the enzymatic extract fed to the dryer of 9.36 g/min for the both drying adjuvants investigated.

Microencapsulation of Ketoprofen in Blends of Acrylic Resins by Spray Drying

Microparticles of ketoprofen entrapped in blends of acrylic resins (Eudragit RL 30D and RS 30D) were successfully produced by spray drying. The effects of the proportion ketoprofen : polymer (1:1 and 1:3) and of spray-drying parameters (drying gas inlet temperatures of 80 and 100°C; microencapsulating composition feed flow rates of 4 and 6 g/min) on the microparticles properties (drug content, encapsulation efficiency, mean particle size, moisture content, and dissolution behavior) were evaluated. Differential scanning calorimetry (DSC) thermograms and X-ray diffractograms of the spray-dried product, the free drug, and the physical mixture between the free drug and spray-dried composition (blank) were carried out. Microparticles obtained at inlet temperature of 80°C, feed flow rate of 4 g/min, and ketoprofen : acrylic resin ratio of 1:3 presented an encapsulation efficiency of 88.1%, moisture content of 5.8%, production yield around 50%, and a higher reduction in dissolution rate of the entrapped ketoprofen. Sigmoidal shape dissolution profiles were presented by the spray-dried microparticles. The dissolution profiles were relatively well described by the Weibull model, a showing high coefficient of determination, R 2, and a mean absolute error between experimental and estimated values of between 4.6 and 10.1%.

Drying of Phytochemical Preparations in a Spouted Bed: Perspectives and Challenges

This article presents an overview of relevant issues to be considered in the development of standardized phytochemical preparations, focusing on the use of the spouted bed as a drying method. Aspects related to the effects of feed composition properties and processing parameters on system performance and product quality are addressed. From the information presented, it can be concluded that the spouted bed technology can be successfully applied for production of high-quality phytochemical preparations suitable for food and pharmaceutical purposes, considering the requirements for product safety, quality, and efficacy. Nevertheless, it should be emphasized that, at this time, the proposed technology is appropriate for small-scale production, mainly due to difficulties concerning scale-up, modeling, and the simulation of spouted bed systems, and also for predicting product properties and system behavior during operation.

Antioxidant activity and physical-chemical properties of spray and spouted bed dried extracts of Bauhinia forficata

Two distinct drying methods (spouted bed and spray drying) were used for production of dried extracts of Bauhinia forficata Link (Leguminosae, Caesalpinoideae). High-quality powder products in terms of physical and chemical properties were obtained. HPLC fingerprints revealed that the chromatographic profiles of flavonoid compounds present in the dried extract did not change significantly, due to drying. In general, the spouted bed drying caused a degradation of total flavonoids than was lower than that of the spray drying. Antioxidant properties of the dried extract, examined by their radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) and inhibition of lipid peroxidation induced by Fe+2 assays (LPO), confirmed their antioxidant potential. The slight reduction in scavenging activity of the dried extracts may be associated with the occurrence of oxidative reactions, decomposition or losses of thermolabile compounds, induced by the heat.

Enzyme encapsulation in magnetic chitosan-Fe3O4 microparticles

Abstract Two simple procedures for the preparation of magnetic chitosan enzyme microparticles have been investigated and used for the immobilisation of endophytic fungus Cercospora kikuchii lipase as model enzyme. In the first case, lipase was entrapped in Fe3O4-chitosan microparticles by cross-linking method, while in the second case magnetic immobilised derivatives were produced using spray drying. Immobilised enzymes showed high enzyme activity retention and stability during storage without significant loss of activity. Glutaraldehyde Fe3O4-chitosan powders presented a higher lipase activity retention and storage stability than the others preparations. However, the immobilised derivatives produced by cross-linking showed higher enzyme activity after reuse cycles. The results proved that the magnetic Fe3O4-chitosan microparticles are an effective support for the enzyme immobilisation since the immobilised lipase showed best properties than the free form.