Seaweeds are an important source of bioactive metabolites for the pharmaceutical industry in drug development. Many of these compounds are used to treat diseases like cancer, acquired immune-deficiency syndrome (AIDS), inflammation, pain, arthritis, as well as viral, bacterial, and fungal infections. This paper offers a survey of the literature for Gracilaria algae extracts with biological activity, and identifies avenues for future research. Nineteen species of this genus that were tested for antibacterial, antiviral, antifungal, antihypertensive, cytotoxic, spermicidal, embriotoxic, and anti-inflammatory activities are cited from the 121 references consulted.

ABSTRACT:The infl ammatory reaction is a response of the organism against an injury and it involves the action of complex events and mediators through of the blood vessels. The present work is a literature survey of the extracts of plants with anti-infl ammatory activity studied in Brazil. The review refers to 75 plants with their families, parts used, type of extract used, bioassay models and their activity.

There has been marked interest in recent years in the use of plants for the treatment of diabetes. Plants have been found in many countries which have been indicated as having hypoglycemic activity. The present work is an up-to-date review with 178 references of crude plant extracts and chemically defi ned molecules with hypoglycemic activity from South, Central and North America. The review refers to 224 plants with their families, parts used and type of extract, organism tested and activity. It also includes 40 compounds isolated from those plants. Some aspects of recent research with natural products from plants directed to the treatment of diabetes are discussed.

Peptic ulcer disease is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Numerous natural products have been evaluated as therapeutics for the treatment of a variety of diseases, including this one. These products usually derive from plant and animal sources that contain active constituents such as alkaloids, flavonoids, terpenoids, tannins and others. The alkaloids are natural nitrogen-containing secondary metabolites mostly derived from amino acids and found in about 20% of plants. There has been considerable pharmacological research into the antiulcer activity of these compounds. In this work we review the literature on alkaloids with antiulcer activity, which covers about sixty-one alkaloids, fifty-five of which have activity against this disease when induced in animals.

The Combretaceae is a large family of herbs, shrubs and trees, comprising about 20 genera and 600 species with tropical distribution around the globe and centers of diversity in Africa and Asia. Some Combretum species are extensively used in traditional medicine against inflammation, infections, diabetes, malaria, bleeding, diarrhea and digestive disorders and others as a diuretic. The present work is a literature survey of Combretum species that have been evaluated for their ability to exert biological activities. A total number of 36 Combretum species are discussed with regard to plant parts used, component tested and bioassay models. This review is of fundamental importance to promoting studies on Combretum species, thereby contributing to the development of new therapeutic alternatives that may improve the health of people suffering from various health problems.