Estrategias para la prevención y el control de intoxicaciones naturales por plantas fotosensibilizantes en bovinos Strategies for the prevention and control of natural intoxication by photosensitizing plants in cattle
The study was conducted at the Livestock Production Enterprise Bacuranao, of the Habana del Este municipality (La Habana province, Cuba), in order to establish a strategy for the prevention and control of natural intoxications by photosensitizing plants in cattle. For such purpose, a presumptive diagnosis on photosensitization was carried out, through the floristic inventory of the plants present in grazing and with the use of the clinical method. Diverse plants which cause hepatogenous photosensitization in the animals were identified, with Ageratum houstonianum Mill., Lantana camara L., Crotalaria retusa L. Crotalaria incana L. and Crotalaria spectabilis Roth standing out. The density of cattle per quadrant, the areas with higher incidence of this type of plants and the animals with dermatitis were determined through the Epidemiological Surveillance System (SIVE), by quadrants and grids. In the evaluation of the relative risk (RR) with and without the presence of the sun and with regards to the green forage intake, it was found that the animals exposed to sunlight and those that consumed forage had 1,85 and 3,17 times more incidence, respectively, of clinical signs associated to the hepatogenous photodynamic dermatitis, with higher levels for the ones that ingested the toxic plant A. houstonianum Mill along with the forage. From these results a plan of general and specific measures was elaborated for the control of toxicosis in the areas contaminated with these plants. It is concluded that the use of SIVE, the botanical census, the support treatments to animals with severe symptoms and the management and feeding measures can improve the efficacy in the control of toxicosis and, in turn, the protection of the animals at risk.
LABORATORY EVALUATION OF PLANT EXTRACTS FOR THE CONTROL OF ASPERGILLUS GROWTH AND AFLATOXIN FORMATION
AND AFLATOXIN FORMATION R.P. GARCIA1 and M.L. GARCIA2 1NCPC/IBS , UPLB, COLLEGE, LAGUNA 4031 PHILIPPINES 2NCPC , UPLB, COLLEGE, LAGUNA 4031 PHILIPPINES ABSTRACT Plant species that were reported to have fungicidal properties on other fungal genera and have of medicinal value was collected and extracted using water. Crude water extracts of 6 out of 97 plant species screened for their fungicidal properties in vitro showed inhibitory activity against Aspergillus flavus and A. parasiticus. The crude extracts of garlic (Allium sativum) was found to be the most effective against Aspergillus flavus and A. parasiticus. In their decreasing order the following plant extract; Kalachuchi (Plumiera acuminata)>Bulakmanok (Ageratum conyzoides)> Sampa-sampalukan (Phyllantus nirure L.) while Talisay (Terminalia catappa L.)>Kakawati (Gliricidia sepium Jacq.) were quite effective on Aspergillus flavus and A. parasiticus, respectively. Also, aflatoxin formation was not detected on potato dextrose broth with the above mentioned crude extracts inoculated with aflatoxin-forming organisms. INTRODUCTION Aflatoxin is highly toxic and carcinogenic fungal metabolite synthesized mainly by Aspergillus flavus and A. parasiticus. A number of circumstancial evidence have linked aflatoxin to liver cancer in humans. A study conducted in the Philippines in 1975. "(ref. 1)" indicate that the incidence of primary liver cancer by region is directly related to the per capita consumption of corn. Corn is one of the commodity in the country that has been found to contain highly toxic levels of aflatoxin under natural conditions "(ref. 2)" Past and current studies on aflatoxin in the Philippines have been mostly on surveys, monitoring contaminated commodities and a very limited studies on chemical control measure on corn were made. Nothing is being done regarding the use of plant extracts with fungicidal activity to control this problem. Extracts of various indigenous and readily available plant materials may be very promising and advantageous in terms of cost, practicability, safety, and availability. This study was conducted primarily to (1) undertake collection of Philippine plants with possible fungicidal activity, (2) extract materials from the different parts of the plant (roots, stems, leaves, and flowers, rhizomes, cloves and fruit peelings) for preliminary toxicity tests, (3) screen and investigate the efficacy of crude plant extracts against Aspergillus flavus and A. parasiticus growth, sporulation, spore germination and aflatoxin formation.
New Sweet-Tasting C21-Pregnane Glycosides from Pericarps of Myriopteron extensum.
Ten novel C21 pregnane glycosides, extensumside C-L (1-10), were isolated as highly sweet-tasting substances from the edible pericarps of Myriopteron extensum (Wight) K. Schum by sensory-guided fractionation and purification. Their structures were determined through 1D and 2D NMR, such as HSQC, HMBC, 1H-1H COSY, HSQC-TOCSY, and ROESY, as well as other spectroscopic analysis combined with chemical evidence. These compounds shared the same aglycone, 3β,16α-dihydroxy-pregn-5-en-20-one, and contained the deoxysugar chain and the glucose chain which were linked to C-3 and C-16 of the aglycone, respectively. The sweetness potency was evaluated by a human sensory panel test and preliminary structure-taste relationship was discussed. The sweetness intensities of these compounds are between 50 and 400 times greater than that of sucrose. Furthermore, quantitation analyses of compounds 1, 3, 4, and 6 in different parts of M. extensum indicated that the concentrations of these sweet components in the pericarps are obviously higher than those in stems and roots.