No abstract

No abstract

No abstract

The current study accentuates the use of botanicals as an alternative to the chemical compounds in vector control by estimating the mosquito larvicidal potential of Ocimum gratissimum L. leaf essential oil against the fourth instar larvae of Aedes albopictus Skuse (Diptera: Culicidae). The chemical composition of essential oil from leaves was evaluated using gas chromatography-mass spectrometry (GC/MS) analysis. GC/MS revealed that the essential oil of O. gratissimum contained 51 compounds. The major chemical constituents identified were 3-allyl-6-methoxyphenol (19.30%), 4-(5-ethenyl-1-azabicyclo (2, 2, 2) octan-2) (16.82%), 1-(2, 5-dimethoxyphenyl)-propanol (12.23%) and 1-(1-hydroxybutyl)-2, 5-dimethoxybenzene (5.53%). The essential oil showed pertinent larvicidal effect, and the LC50 value in 24 h was 26.10 ppm (LC90 = 82.83 ppm). Aromatic plants and their essential oils are very important sources of many compounds that are used for different applications, and they are more promising pesticides or insecticides for control of mosquito populations than synthetic ones. The results of the present investigation justify the larvicidal potential of leaf essential oil of O. gratissimum as a safer and more effective larvicide against A. albopictus.

Cancer is one of the most dreadful diseases engulfing mankind with the toll of life being taken away. Researchers always focus on traditional medicines to overcome such diseases because of the side effects and high cost of synthetic drugs making it inaccessible especially for inhabitants of developing countries. Isodon is a genus well established in Chinese folk medicines and have reported activities of anticancer effect with low toxicity due to the presence of biologically active diterpenoids. Thus, a study on the anticancer potential of Isodon coetsa was conducted using cytotoxic and cell viability assays which included Allium cepa assay, Evans blue staining and Trypan blue exclusion assay. A. cepa assay revealed the cytotoxic activity of I. coetsa which increased with increasing concentrations and time durations. Evans blue staining of the methanolic extract treated A. cepa root meristems also showed increase in activity in dose dependent manner which confirmed the ability of plant extracts to induce cell death. Cell viability assays conducted against methanolic extract treated DLA and EAC cell lines also revealed cytotoxic activity which also increased with increase in concentration of the extract. The IC50 value of the extract was found to be 1.21 ± 0.02 mg/mL against DLA cell line and 1.36 ± 0.01 mg/mL against EAC cell line. The results obtained establish the ability of I. coetsa to induce cell death in dividing cells which is an essential phenomenon in anticancer therapy. The assays conducted thus affirm the use of the species in folk medicines as well as makes it a promising candidate in anticancer research.

Cytotoxicity and giant cell formation induced by lemon yellow and orange red synthetic food colorants were evaluated in the present study. The aqueous solutions of both the dye solutions were tested for cytotoxicity using Allium cepa assay. Frequency of giant cells were determined after treating the root tips with different concentrations of both food colorant solutions viz., 0.005, 0.01, 0.05, 0.1 % for varying time durations (1/2, 1, 2, 3 h). These colorants may cause giant cell formation primarily by interfering with the normal course of mitosis. Giant cells showing multiple aberrations viz. bridged and binucleate condition, cellular fragmentation, nuclear lesion, double and multiple nuclear lesions, double nuclear peaks and cellular breakage, elongated nucleus, nuclear budding, hyperchromasia, micronucleus, nuclear erosion, pulverized nucleus etc. were induced in root tips treated with both of the colorants. The synthetic food colorant treated cells showed inhibition of cell division and induction of giant cells. A dose dependant decrease in the mitotic index [88.20 % (c(-ve), 3h) to 81.54 % (Lx4, 3h) and 88.20 % (c(-ve), 3h) to 73.17 % (Ox4, 3h)] was observed. All mitotic phases show significant induction of giant cells when treated with both food colorants. Interphase stage shows higher percentage of giant cells, whereas in cytokinesis it was negligible. The orange red food colorant is observed to be more toxic because it recorded higher percentage of giant cell induction when compared with lemon yellow [27.93 % (Lx4, 3h) and 28.07 % (Ox4, 3h)].

The present study examined the apoptosis inducing effects of Amaranthus spinosus L. aqueous extract in Allium cepa root meristematic cells and human erythrocytes. Cytogenetic assay revealed many apoptosis inducing cytogenetic aberrations viz., cytoplasmic breakage, cytoplasmic disintegration, cytoplasmic shrinkage, receding of cytoplasm, cytoplasmic vacuolation, enucleated cell, ghost cell, nuclear vacuolation, nuclear fragmentation and nuclear disintegration. A remarkable modification of red blood cell surface morphology was observed in the result of RBC assay. The treated RBCs show membrane blebbing and shrinkage, features typical for apoptosis in nucleated cells. Significant induction of cell death was observed in treated Allium root tip cells after Evans blue staining, disclosing the membrane damage potential of the plant extract. TTC assay results in reduced mitochondrial/ metabolic activity in Allium root tip cells after treatment, designating the adverse effect of plant extract on mitochondrial respiratory chain. These results confirm the apoptosis inducing potential of A. spinosus extract. Confirming the present results by further in vitro studies, it can be effectively targeted against cell proliferation during cancer treatment by inducing apoptosis. Thus from the present investigation it can be concluded that the aqueous extract of A. spinosus exhibited apoptosis induction and cytotoxic activities.

Isodon coetsa (Buch.-Ham. ex D.Don) Kudo, a perennial herb used in traditional Chinese folk medicines as an antibacterial, antiinflammatory, and antitumour agent, was subjected to toxicity analysis. Cytotoxic screening using the Allium L. assay was done with extracts containing polar and nonpolar compounds as well as with polar compounds alone. Root tips were treated with different concentrations of both the extracts, 0.005%, 0.01%, 0.05%, and 0.1%, for varying time durations (30 min, 1 h, 2 h, and 3 h). Extremely significant levels of chromosome abnormality (P < 0.001) were observed with the extracts when compared with the positive control (0.01% methyl parathion), but the extract with polar and nonpolar compounds showed higher abnormality percentage. Not much variation was observed in the mitotic index when compared to the negative control (distilled water). Studies revealed many clastogenic and nonclastogenic abnormalities. The major abnormalities included chromosome fragments, stickiness, ring chromosomes, chromosome bridges, pulverization, binucleate cell, micronucleus, ball metaphase, chromosome laggards, and shift in microtubule organizing center. The results showed that the nonpolar components possessed more clastogenic activity, which can be specifically targeted in order to destroy cancer cells. The toxic activity of extracts also suggests the need of judicious use of I. coetsa in folk medicines.