Biogeography of mangrove and saltmarsh vegetation: implications for conservation and management in Australia

Despite an undeserved reputation for being dull and homogenous systems, mangal and saltmarsh in Australia have highly complex patterns and processes. Their role as key edge systems between land and sea has implications for many species which have larval stages in mangal and saltmarsh, but spend adult life as benthic, pelagic or demersal species. Many such species are also important commercially. Mangal and saltmarsh are both highly dynamic systems, reacting rapidly to changes in hydrological condition and sedimentation. In many areas of the world mangal and saltmarsh are threatened systems, especially near human habitation. Appropriate management strategies for mangal and saltmarsh are therefore critical for both conservation and sustainable use, the two key objectives of the Convention on Biological Diversity. Clearing and associated development, invasion of alien species, pollution effects and poor management are the key threats to these systems. Management at a bioregional level, including the development of a comprehensive system of protected areas, is identified as the key management strategy which will ensure an adequate future for these dynamic systems.     

Medicinal plants used for dogs in Trinidad and Tobago

This paper documents ethnoveterinary medicines used to treat dogs in Trinidad and Tobago. In 1995, a 4-stage process was used to conduct the research and document the ethnoveterinary practices. Twenty-eight ethnoveterinary respondents were identified using the school-essay method, which is a modified rapid rural appraisal (RRA) technique. Semi-structured interviews were held with these respondents as well as with 30 veterinarians, 27 extension officers and 19 animal-health assistants and/or agricultural officers, and the seven key respondents that they identified. The final step involved hosting four participatory workshops with 55 of the respondents interviewed to discuss the ethnoveterinary data generated from the interviews and to determine dosages for some of the plants mentioned. Supplementary interviews were conducted in 1997 and 1998.

Seeds of Carica papaya, and leaves of Cassia alata, Azadirachta indica, Gossypium spp., Cajanus cajan and Chenopodium ambrosiodes are used as anthelmintics. The anthelmintics Gossypium spp. and Chenopodium ambrosiodes are the most frequently used species. Crescentia cujete pulp, Musa spp. stem exudate, the inside of the pods of Bixa orellana, leaves of Cordia curassavica and Eclipta alba plant tops are used for skin diseases. Musa spp. stem exudate, seeds of Manilkara zapota, Pouteria sapota and Mammea americana and leaves of Cordia curassavica, Scoparia dulcis and Nicotiana tabacum are used to control ectoparasites. Dogs are groomed with the leaves of Cordia curassavica, Bambusa vulgaris and Scoparia dulcis. Psidium guajava buds and leaves and the bark of Anacardium occidentale are used for diarrhoea. Owners attempt to achieve milk let-down with a decoction of the leaves of Stachytarpheta jamaicensis. The plant uses parallel those practised in human folk medicine in other Caribbean countries and in other tropical countries.     

Antioxidant mechanisms of enzymatic hydrolysates of beta-lactoglobulin in food lipid dispersions

The antioxidant activities of aqueous phase beta-lactoglobulin (beta-Lg) and its chymotryptic hydrolysates (CTH) were compared in this study. Proteins and peptides have been shown to inhibit lipid oxidation reactions in oil-in-water emulsions; however, a more fundamental understanding of the antioxidant activity of these compounds in dispersed food lipid systems is lacking. CTH was more effective than an equivalent concentration of beta-Lg in retarding lipid oxidation reactions when dispersed in the continuous phase of Brij-stabilized oil-in-water emulsions (pH 7). Furthermore, it was observed that CTH had higher peroxyl radical scavenging and iron-binding values than beta-Lg. Liquid chromatography-mass spectrometry (LC-MS) was used to measure the rate of oxidation of three oxidatively labile amino acid residues (Tyr, Met, and Phe) in certain CTH peptide fragments. Significant oxidation of specific Tyr and Met residues present in two separate 12 amino acid peptide fragments was observed in the days preceding lipid oxidation (39 and 55% of Tyr and Met were oxidized, respectively, by day 4 of the study); however, no significant oxidation of the Phe residue present in a specific 14 amino acid peptide fragment could be observed during the same time period. These data could suggest that Met and Tyr residues are capable of scavenging radical species and have the potential to improve the oxidative stability dispersed food lipids.