| Melastoma affine D.Don is a shrub which is distributed in tropics and subtropics. In Fujian province, M.affine bears purple or light red flowers from May to June. December and November is the ripening time of its fruits, which are berry-like and edible. Traditionally, M.affine was regarded as a kind of Chinese medicine for the treatment of inflammation. The paper studies the microstructure including leaf, petal, seed, pollen by means of scanning electron microscope and transmission electron microscope. Nutrition components of the fruit, fatty acids of seed oil, red pigment and flavonoids in the leaf are studied at the same time. The main results are as follows:1. Micromorphological characters of leaf epidermis, petal epidermis, seed and pollen of M.affine are examined by SEM and TEM. Unicellular hairs are observed in upper and lower leaf epidermis. Stomatal apparatus (their average size is 8.37X4.68um) are located in the base of trichomes which have many papillaes. The inner margin of the outer stomatal rim is nearly smooth and the cuticular membrane is striated. A comparison of the petal ' s micromorphology of M.affine with that of M.dodecandrum and M.candidum shows several different features such as the anticlinal walls and periclinal walls ect. The shape of seed is nearly triangular and the seed coat is densely covered with tubercles with radiate stripe. Under SEM, the pollen is 14.8 (14.5-15.6)X 14.5 (12.5-16.7) um, subspheroidal in shape, N3P4C5 and the exine ornamentation is striated. Under TEM, the exine is composed of three layers: tectum, columellae and foot layer with 1.5um in thickness. All of these can be used as the scientific basis for pharmacentical identification of M.affine.2. The nutrition components of the fruit are studied by chemical methods. The compostions are water 84.22%, Vitamin C 0.9% mg ?100g~'.FW, total acid 0.33%.FW, totalsugar 4.77%.FW, reducing sugar 3.88%.FW, pectin 5.54%.DW, total carotinoid 999.28 ug - 100g-1.FW, crude protein 7.34%.DW, carbon 44.18%.DW. Seventeen kinds of amino acids are found in pulp and seed and Thr is regarded as restrictive amino acid among the essential amino acid. The mineral elements have the proper ratio.3. The content of the unripe fruit seed oil is 5.31% and that of the ripe fruit seed oil is 4.17%. The acid value and the iodine value of the former are higher than the latter ' s and the saponification value is equal. The fatty acid in the two kinds of seed oils are determined by a method of capillary GC. The results show that the major components of fatty acid in seed oil are unsaturated acid and the relative content of Linolenic acid is the highest, about 86.52% and 85.73% in the unripe and ripe fruit seed oil. The second is palmitic acid. The composition of fatty acid of seed oil changes slightly during the ripening stage of the fruit.4. M.affine D.Don possesses abundant pigment in the Placenta. The red pigment belongs to water-solvent anothocyanins. In acid solution, the stability of the pigment is good. It is heat resistant and reducing medium tolerant but sensitive to intense light and oxidant. Fe3+, Cu2+, Mn2+, Zn2+ evidently degrade the pigment, but Na+, Mg2+, A13+, glucose, sucrose and C6H3COONa have no harmful effect on it. In a word, The red pigment can be a natural healthy additive in avoiding its shortage.5. It is found that the effect of compounds extract by alcohol solution is better than those by water. The contents of anti-microbial compounds are old leaf >new leaf >stem. They have no effects on Aspergillus flavus, Aspergillus niger and penicillium chrysogenum but evident inhibitive effects on Escherichia coli, Bacillus subtilis, Staphylococcus aureaus, Proteus vulgaris and Sarcina lutea. On the base of preliminary experiment, flavonoids may be regarded as the anti-microbial compound and be measured. It is revealed that the content of flavonoids is the highest in May in leaf and stem. A compound is isolated from the ethyl acetate extraction of leaf by a two-step thin layer chromatographic procedure. After...
|
PDF Full Text Request