Development, characterization and antioxidant activity of polysorbate based O/W emulsion containing polyphenols derived from Hippophae rhamnoides and Cassia fistula

The objective of this study was to develop a pharmaceutical O/W emulsion containing plant-derived polyphenol extracts and evaluate its stability and antioxidant activity. O/W emulsions were prepared using ionic surfactant polysorbate 80 (Tween 80®). The odorwas adjusted with few drops of blue sea fragrance. DPPH (1,1-diphenyl-2-picrylhydrazyl) assay was used to evaluate the antioxidant activity of the plant extracts alone and emulsions containing these extracts. Physical stability was assessed by submitting the emulsions to storage at 8 ºC, 25 ºC, 40 ºC and 40 ºC + 70% RH (relative humidity) for two months. Various physical characteristics of emulsions monitored, include color, creaming, liquefaction, centrifugation and pH. Brookfield rotational rheometer was used to determined viscosities and rheological behavior of emulsions. Different types of emulsion were determined microscopically, while pH values of emulsions were measured by a pH meter. Electrical conductivity data confirmed that the outer phase was water. Samples presented an acceptable pH value for an external topical use. Shear thinning behaviour was observed for all emulsions. The polyphenol-rich-plant-derived extracts alone and the extract containing emulsions showed good antioxidant activities. This research confirmed that the method used was suitable for preparing emulsions with Hippophae rhamnoids and Cassia fistula extracts, suggesting that those emulsions are suitable for topical use.

O presente estudo objetivou o desenvolvimento de uma emulsão farmacêutica óleo-água contendo extratos de plantas ricos em polifenóis, a comparação à sua formulação-controle e a avaliação de sua estabilidade, assim como de sua capacidade antioxidante. Extrato concentrado de Hippophae rhamnoids e Cassia fistula foi encapsulado no interior da fase oleosa da emulsão O/W. As emulsões foram preparadas usando o tensoativo iônico monooleato sorbital de polioxietileno (Tween 80®). O odor foi ajustado pela adição de algumas gotas de fragrância azul do mar. O ensaio do DPPH (1,1-difenil-2-picrilidrazil) foi utilizado para avaliar a atividade antioxidante dos extratos de plantas sozinhos e nas emulsões contendo os extratos. A estabilidade física foi avaliada submetendo os cremes a diferentes temperaturas de estocagem, como a 8 ºC, 25 ºC e 40 ºC e a 40% + 70% de umidade relativa por um período de 2 meses. As características físicas das emulsões foram monitoradas por 2 meses incluindo cor, cremosidade, liquefação, centrifugação e pH. O reômetro rotacional de Brookfield foi utilizado para determinar a viscosidade e o comportamento reológico das emulsões. O programa Rheocalc Brookfield foi utilizado para análise dos dados. As características organolépticas também foram avaliadas. O tipo de emulsão foi determinado microscopicamente, enquanto o pH das emulsões foi avaliado por meio de um pHmetro. A estabilidade farmacêutica esperada das emulsões foi alcançada dentro dos dois meses de estudo. Os resultados da condutividade elétrica confirmaram que a fase externa da emulsão era composta de água. O pH das amostras estava dentro da normalidade para uso tópico. A emulsão apresentou boa fragrância e pode ser retirada da pele com água após a aplicação, características desejáveis em emulsões O/W. Os extratos vegetais ricos em polifenóis isolados ou nas emulsões apresentaram boa atividade antioxidante. Nossos estudos confirmaram que o método utilizado foi adequado para preparar a emulsão semi-sólida contendo extratos de Hippophae rhamnoids e Cassia fistula. Nossos achados sugerem que emulsões contendo extratos de Hippophae rhamnoids e Cassia fistula são adequados para o uso tópico.

Cassia spectabilis (DC) Irwin et Barn: a promising traditional herb in health improvement.

The genus Cassia, comprising about 600 species widely distributed worldwide is well known for its diverse biological and pharmacological properties. Cassia spectabilis (sin Senna spectabilis) (DC) Irwin et Barn (Fabaceae) is widely grown as an ornamental plant in tropical and subtropical areas. C. spectabilis has been commonly used in traditional medicine for many years. Information in the biomedical literature has indicated the presence of a variety of medicinally-important chemical constituents in C. spectabilis. Pharmacological studies by various groups of investigators have shown that C. spectabilis possesses significant biological activity, such as antibacterial, antibiofilm, antifungal and antioxidant properties. Beside this, toxicity studies of this plant have revealed no toxic effect on mice. In view of the immense medicinal importance of C. spectabilis, this review aimed at compiling all currently available information on C. spectabilis's botany, phytochemistry, pharmacology, and mechanism of actions, toxicology and its ethnomedicinal uses.

Cryptococcus neoformans carried by Odontomachus bauri ants.

Cryptococcus neoformans is the most common causative agent of cryptococcosis worldwide. Although this fungus has been isolated from a variety of organic substrates, several studies suggest that hollow trees constitute an important natural niche for C. neoformans. A previously surveyed hollow of a living pink shower tree (Cassia grandis) positive for C. neoformans in the city of Rio de Janeiro, Brazil, was chosen for further investigation. Odontomachus bauri ants (trap-jaw ants) found inside the hollow were collected for evaluation as possible carriers of Cryptococcus spp. Two out of 10 ants were found to carry phenoloxidase-positive colonies identified as C. neoformans molecular types VNI and VNII. The ants may have acted as a mechanical vector of C. neoformans and possibly contributed to the dispersal of the fungi from one substrate to another. To the best of our knowledge, this is the first report on the association of C. neoformans with ants of the genus Odontomachus.

Cryptococcus neoformans carried by Odontomachus bauri ants

Cryptococcus neoformans is the most common causative agent of cryptococcosis worldwide. Although this fungus has been isolated from a variety of organic substrates, several studies suggest that hollow trees constitute an important natural niche for C. neoformans. A previously surveyed hollow of a living pink shower tree (Cassia grandis) positive for C. neoformans in the city of Rio de Janeiro, Brazil, was chosen for further investigation. Odontomachus bauri ants (trap-jaw ants) found inside the hollow were collected for evaluation as possible carriers of Cryptococcus spp. Two out of 10 ants were found to carry phenoloxidase-positive colonies identified as C. neoformans molecular types VNI and VNII. The ants may have acted as a mechanical vector of C. neoformans and possibly contributed to the dispersal of the fungi from one substrate to another. To the best of our knowledge, this is the first report on the association of C. neoformans with ants of the genus Odontomachus.

A distinct tymovirus infecting Cassia hoffmannseggii in Brazil.

Leaves of Cassia hoffmannseggii, a wild fabaceous species found in the Atlantic Forest, with a severe mosaic symptom were collected in Pernambuco State, Brazil. By transmission electron microscopy, two types of virus particles were found: the first was recognized as particles of a potyvirus, which was later identified as Cowpea aphid-borne mosaic virus; and the second was isometric and present in high concentration. The observation of vesicles at the periphery of chloroplasts suggested a tymovirus infection, which was confirmed by subsequent assays. A serological assay against several tymovirus antisera resulted in positive reaction of this tymo-like virus with an antiserum of Passion fruit yellow mosaic virus. By means of RT-PCR and using degenerated primers for the conserved region of RNA-dependent RNA polymerase (RdRp) gene of tymoviruses, a specific DNA fragment was amplified and sequenced. Based on this sequence, a specific forward primer was synthesized and successfully used to amplify the 3' terminal genome region, containing the partial RdRp gene and the complete coat protein (CP) sequences. The CP was 188 amino acids (aa) long, and the highest CP aa identity was observed with Kennedya yellow mosaic virus (61 %). Based on the current ICTV demarcation criterion, this isolate was considered as a distinct tymovirus and tentatively named as Cassia yellow mosaic-associated virus.

[Identification of six species of Cassia seeds by capillary electrophoresis].

OBJECTIVE: To identify Cassia seeds of six species by capillary electrophoresis. METHOD: The water-soluble extracts of Cassia seeds of six species were analyzed by capillary electrophoresis. The running buffer was 0.1 mol.L-1 borate, 0.1 mol.L-1 SDS, pH 8.5. The separation voltage was 25 kV. RESULT: Four common peaks could be found in the electropherograms of six species Cassia seeds, and the characteristic peaks could also be observed. CONCLUSION: Fingerprints of the six species of Cassia seeds show significant differences, which can be used for their identification.

The senna drug and its chemistry.

Senna consists of the dried leaflets or fruits of Cassia senna (C. acutifolia) known in commerce as Alexandrian senna and of Cassia angustifolia commonly known as Tinnevelly senna. The senna plants are small shrubs of Leguminosae cultivated either in Somalia, the Arabian peninsula and near the Nile river. Tinnevelly senna is obtained from cultivated plants mainly in South India and Pakistan. Owing to the careful way in which the plant is harvested, the leaflets of the drug are usually little broken. Damaged leaves and lower quality products are often used for making galenicals. The senna pods (fruits) are collected during the same period as the leaves, then dried and separated into various qualities. The active principle of Senna was first isolated and characterized by Stoll in 1941. The first two glycosides were identified and attributed to the anthraquinone family. These were found to be dimeric products of aloe emodin and/or rhein which were named sennoside A and sennoside B. They both hydrolyze to give the aglycones sennidin A and B and two molecules of glucose. Later work confirmed these findings and further demonstrated the presence of sennosides C and D. Small quantities of monomeric glycosides and free anthraquinones seem to be present as well. The active constituents of the pods are similar to those of the leaves but present in larger quantities. Two naphthalene glycosides isolated from senna leaves and pods are 6-hydroxymusicin glucoside and tinnevellin glucoside. Both compounds can be utilized to distinguish between the Alexandrian senna and the India senna, since tinnevellin glucoside is only found in the latter and the first only in the C. senna.(ABSTRACT TRUNCATED AT 250 WORDS)