ABSTRACT
Biologically active compounds with different modes of action, such as antiproliferative, antioxidant, antimicrotubule, have been isolated from algae and cyanobacteria. The present study was designed to evaluate antiangiogenic and antiproliferative potential of dichloromethane and methanol (2:1) extracts of different cyanobacteria. Further fingerprinting of the activity possessing extracts were carried out using ESI-LC-MS/MS. Extracts (25, 50 and 100 µg) were screened in the vascular endothelial growth factor (VEGF) induced angiogenesis in inovo chick chorioallontoic membrane assay (CAM) at various concentrations using thalidomide and normal saline as positive and untreated control groups respectively. The extracts were also evaluated for their antiproliferative activity by MTT assay using HeLa cancer cell line. The results obtained from the various algal extracts did not show any significant antiangiogenic activity as compared to VEGF control. Oscillatoria sp. and Lyngbya officinalis exhibited significant anti-proliferative activity at IC50 values of 220 and 260 µg/mL respectively. ESI-LC-MS/MS of L. officinalis showed the presence of lyngbyatoxin-A and that of Oscillatoria sp. reveals the presence of malyngamide-J suggesting the possibility of antiproliferative activity.
ABSTRACT
Cyanobacterium Spirulina is in ever increasing demand internationally due to its high value bio-chemical constituents which find application in areas like health foods and therapeutics, especially for its high protein content. The Spirulina protein is superior to practically all proteins including those from legumes, and is comparable to milk proteins for that matter. Moreover, interest in its phycocyanin, b-carotene, polyunsaturated acids (PUFA) and super oxide dismutase (SOD) contents has attracted the attention of researchers the world over towards protecting, promoting and preserving the production of this useful micro-organism. The present investigation deals with examining the impact of various physical stresses viz. intensity and photo-period of light, varying chromatic regimes, temperature, pH, etc., on the growth of Spirulina platensis-S5 to spell the appropriate conditions for raising the strain in laboratory. No earlier report of this kind is available, so far, to our knowledge. The experimental results suggested that 16 : 8 hours light : dark regime at light intensity of 2000 +/- 200 lux, temperature of 30 +/- 1 degrees C and pH of 9.1 are the optimal growth conditions for the test micro-organisim. The growth under different chromatic regimes observed the order yellow> red> green> blue.
Subject(s)
Cells, Cultured , Cyanobacteria/growth & development , Environment , Hot Temperature , Humans , Hydrogen-Ion Concentration , Light , Stress, PhysiologicalABSTRACT
In the present study, changes in velocity of cytoplasmic streaming in the giant internodal cells of Nitella for varying concentration of the pesticides, 2,4-D, dieldrin, malathion, methyl parathion and endosulfan, were measured. Marked decrease in the velocity of cytoplasmic streaming was found at the concentrations of 0.01, 0.1, 1, 10 and 100mM. Dieldrin was the most toxic to all the pesticides investigated, followed by methyl parathion, endosulfan, malathion and 2,4-D. Threshold values for dieldrin, methylparathion, endosulfan, malathion and 2,4-D as indicated by the onset of decrease in the normal cytoplasmic streaming velocity were less than 6.25 x 10(-6), 2.5 x 10(-5), 5 x 10(-5), 5 x 10(-5) and 1.25 x 10(-5)M respectively. Cessation of streaming was noticed above 1mM in dieldrin and above 10mM when exposed to methylparathion and endosulfan. Cessation of streaming was not seen up to 100mM concentration of 2,4-D and malathion.
Subject(s)
Cytoplasm/drug effects , Environmental Monitoring , Nitella/drug effects , Pesticides/toxicityABSTRACT
A single polypeptide protein (MP 66) of molecular weight 66 kDa purified to homogeneity from melanosomes of normal human skin epidermal melanocytes, was partially characterized. The isoelectric point of MP 66 is in the range of 7.3 to 7.6. This protein, which was shown to inhibit partially purified human skin tyrosinase activity at pH 6.8, also inhibits murine tyrosinase at pH 6.8. However, at pH 5.0, it stimulates murine tyrosinase activity. The physiological implications of these results are discussed.