Cellular Responses to Cisplatin-Induced DNA Damage

Cisplatin is one of the most effective anticancer agents widely used in the treatment of solid tumors. It is generally considered as a cytotoxic drug which kills cancer cells by damaging DNA and inhibiting DNA synthesis. How cells respond to cisplatin-induced DNA damage plays a critical role in deciding cisplatin sensitivity. Cisplatin-induced DNA damage activates various signaling pathways to prevent or promote cell death. This paper summarizes our current understandings regarding the mechanisms by which cisplatin induces cell death and the bases of cisplatin resistance. We have discussed various steps, including the entry of cisplatin inside cells, DNA repair, drug detoxification, DNA damage response, and regulation of cisplatin-induced apoptosis by protein kinases. An understanding of how various signaling pathways regulate cisplatin-induced cell death should aid in the development of more effective therapeutic strategies for the treatment of cancer

Lactic Acid Bacteria Mediated Induction of Defense Enzymes To Enhance the Resistance in Tomato against Ralstonia Solanacearum Causing Bacterial Wilt

The biocontrol agent Lactic acid bacterium (LAB) was used against the bacterial wilt caused by Ralstonia solanacearum. The present investigation focuses on the role of defense related enzymes in imparting resistance to tomato plants against R. solanacearum. The LAB isolate was tested for its ability to induce the production of defense-related enzymes in treated tomato seedlings. Tomato seedlings were raised from LAB pretreated seeds, were challenge inoculated with R. solanacearum, harvested at different time intervals (0–72 h) and assayed for defense enzyme activity. The LAB treated seeds showed increase in germination percentage (6%) and seedling vigour index (259) compared with control. Treatment of tomato seedlings with LAB isolate induced a significant amount of Peroxidase (POX), Polyphenol oxidase (PPO), Phenylalanine ammonialyase (PAL), total phenolics and β-1,3-glucanase activities. The activities of PAL, POX, PPO and β-1,3-glucanase reached maximum at 24 h, 24 h, 32 h and 24 h respectively after challenge inoculation. Increased accumulation of phenolics was noticed in plants pre-treated with LAB. Native PAGE analyses of POX and PPO were carried out for the time course of enzyme activities and the isoforms of POX and PPO were examined. In field study, ten isolates of R. solanacearum treated plots yielded an average of 32.4–50 kg/m2 and LAB treated plots an average of 153.5 kg/m2. As compared to the control, LAB increased the yield by 15.3% (8.2 kg/m2) and the pathogen infected plants and pre-treated with LAB gave an average of 55% (28.3 kg/m2 compared to the infected plots). Field experiment results indicated that LAB exhibited 61.1% of disease reduction of bacterial wilt in tomato

Evaluation of in vitro antioxidant and antidiabetic activities from Amomum nilgiricum leaf extract

In the present study, hexane, ethyl acetate and methanol fraction of Amomum nilgiricum leaf was evaluated for antidiabetic efficacy, scavenging activities, followed by estimation of total phenol, total flavonoids. In the present study, a significant amounts of total phenolics (79.92±1.58 mg/g) and flavonoids (21.74± 0.89 mg/g) were showed from Ethyl acetae fraction. H2O2 scavenging activity (97.62±2.89%) with IC50 value of 78.57 µg/ml concentrations. Ethyl acetate fraction exhibited maximum inhibitory activity of glucose movement into outer solution across dialysis membrane at 250 µg/ml as compared to the control. The ethyl acetate fraction revealed maximum insulin secretory activity (130.5±3.66%) in RIN-m5F cells. Methanol fraction recorded maximum glucose uptake percent in yeast cells (67.08±1.68%) when compared to standard metronidazole (68.06±0.73%). This study scientifically validates the antidiabetic activity of A. nilgiricum. Hence, in view of its comparative hypoglycemic strength, it can work as a valuable healing agent in treating diabetes

Insignificant antifungal activity of plant extracts on Malassezia furfur

The aim of present study was to investigate the antimalassezial potential of the selected plant extracts known to possess medicinal values. Materials and Methods: The crude extracts of five botanicals were evaluated against Malassezia furfur. The dried and pulverized plant material was extracted with water and also successively extracted with hexane, chloroform, and methanol, using the Soxhlet apparatus. The antimicrobial activity assay was done by disk diffusion and 96-well plate microdilution method. Results: The results point toward the fact that all the tested extracts extracted in solvents of different polarities exhibited no antifungal activity. Conclusion: The tested extracts did not have, or had too little, antifungal activity to be used as a promising source of novel antimicrobial substances against M. furfur

Characterization of ankaflavin from Penicillium aculeatum and its cytotoxic properties

The pigment was extracted from Penicillium aculeatum, purified and characterized as Ankaflavin by spectroscopic analysis. The stability of the pigment was determined under various conditions and was found to possess high stability. The cytotoxicity property of the purified pigment was determined by MTT assay in MCF-7, HCT116 and PC-3 and the studies were compared with its activity in CHOK1 cells. In MCF-7 and in CHOK 1 cells, the pigment exhibited very less toxicity. However, significant cytotoxicity was observed in HCT116 and PC-3 cells with IC50 of 162 mu g mL(-1) and 85 mu g mL(-1) for HCT116 and PC-3 cells respectively. In vitro toxicity was tested by haemolysis assay and MTT assay in HEK 293 cells. The pigment showed least cytotoxicity (<5%) at 160 and 320 mu g mL(-1) concentrations HEK 293 cells and negligible (<5%) toxicity on human erythrocytes at 160 and 320 mu g mL(-1), the highest concentrations tested

Efficacy of indigenous plant growth-promoting rhizobacteria and Trichoderma strains in eliciting resistance against bacterial wilt in a tomato

Bacterial wilt of tomato caused by Ralstonia solanacearum is a serious threat to tomato production worldwide. For eco-friendly management of bacterial wilt of tomato, the rhizospheric microorganisms belonging to the genera Bacillus (6 isolates), Brevibacillus (1 isolate), Pseudomonas (3 isolates), and Trichoderma (8 isolates) were studied for their ability to induce innate immunity in tomato, individually and in combination against R. solanacearum in greenhouse and field studies. In laboratory studies, maximum germination percent of 93%, vigor index of 1609 was noted in seed bacterization with P. fluorescens Pf3, followed by 91% germination, vigor index of 1593 in treatment with T. asperellum T8 over control. Under greenhouse conditions, protection against bacterial wilt in individual treatments with PGPRs ranged from 38 to 43% and Trichoderma sp. ranged from 39 to 43% in comparison to control. In comparison to individual seed treatment, among different combinations, maximum seed germination percent of 97% was recorded with combination P. fluorescens Pf3 + T. longibrachiatumUNS11. In greenhouse studies’ combination seed treatment with P. fluorescens Pf3 + T. longibrachiatumUNS11 offered an impressive 62% protection against bacterial wilt over control. Similarly, under field conditions, seed treatment with P. fluorescens Pf3 + T. longibrachiatumUNS11 resulted in 61% protection. The innate immunity triggered by eco-friendly seed treatment was analyzed by expression to defense-related enzymes such as peroxidase, phenylalanine ammonialyase, and polyphenol oxidase in comparison to control. This study indicated that the potential benefits of using combination treatments of beneficial microorganisms in effectively inducing resistance are possible for dual benefits of enhanced plant growth, tomato yield, and pathogen suppression

Evaluation of biological efficacy of Trichoderma asperellum against tomato bacterial wilt caused by Ralstonia solanacearum

Abstract Bacterial wilt, caused by soilborne bacterium Ralstonia solanacearum, is one of the most severe diseases of tomato worldwide, and no successful control measures are available to date. In the present study, a sustainable alternative tool such as use of fungi from tomato rhizosphere is being utilized to combat the pathogen attack. The application of Trichoderma asperellum (T4 and T8) isolates delayed wilt development, effectively decreased the disease incidence, increased fruit yield, and improved plant growth promotion under field conditions. The T. asperellum treatment decreased the disease incidence by 51.06% (RS + T4) and 52.75% (RS + T8) in Bhoomishettihalli (BH) and 47.21% (RS + T4) and 46.83% (RS + T8) in Madanahalli (MH) plots, respectively when compared with the pathogen-treated plot in year 2014. Correspondent decreases in year 2015 were 50.69% (RS + T4) and 52.38% (RS + T8) in BH and 48.18% (RS + T4) and 49.22% (RS + T8) in MH plots. In year 2014, T. asperellum (T4 and T8) treatment enhanced the yield with 5.45 t/ha and 5.50 t/ha in BH plot and 6.66 t/ha and 6.93 t/ha in MH plot, respectively, when compared with infected plots. In year 2015, T. asperellum (T4 and T8) treatment enhanced the yield with 5.29 t/ha and 5.51 t/ha in BH plot and 5.82 t/ha and 5.66 t/ha in MH plot, respectively, when compared with infected plots. The disease control and yield enhancement were highest at T8, followed by T4. Increase in the level of peroxidase (POX), phenylalanine ammonium lyase (PAL), polyphenol oxidase (PPO), β-1,3-glucanase and total phenol activities at 12th, 10th, 14th, 12th, and 10th days, respectively, after pathogen inoculation was observed. This indicates the induction of plant resistance mechanism by T. asperellum against R. solanacearum in tomato plants under field conditions

GC–MS analysis of phytoconstituents from Amomum nilgiricum and molecular docking interactions of bioactive serverogenin acetate with target proteins

Amomum nilgiricum is one of the plant species reported from Western Ghats of India, belonging to the family Zingiberaceae, with ethno-botanical values, and is well-known for their ethno medicinal applications. In the present investigation, ethyl acetate and methanol extracts of A. nilgiricum were analyzed by Fourier transform infrared spectrometer (FTIR) and gas chromatography-mass spectrometry (GC–MS) to identify the important functional groups and phytochemical constituents. The FTIR spectra revealed the occurrence of functional characteristic peaks of aromatic amines, carboxylic acids, ketones, phenols and alkyl halides group from leaf and rhizome extracts. The GC–MS analysis of ethyl acetate and methanol extracts from leaves, and methanol extract from rhizomes of A. nilgiricum detected the presence of 25 phytochemical compounds. Further, the leaf and rhizome extracts of A. nilgiricum showed remarkable antibacterial and antifungal activities at 100 mg/mL. The results of DPPH and ferric reducing antioxidant power assay recorded maximum antioxidant activity in A. nilgiricum methanolic leaf extract. While, ethyl acetate leaf extract exhibited maximum α-amylase inhibition activity, followed by methanolic leaf extract exhibiting aldose reductase inhibition. Subsequently, these 25 identified compounds were analyzed for their bioactivity through in silico molecular docking studies. Results revealed that among the phytochemical compounds identified, serverogenin acetate might have maximum antibacterial, antifungal, antiviral, antioxidant and antidiabetic properties followed by 2,4-dimethyl-1,3-dioxane and (1,3-13C2)propanedioic acid. To our best knowledge, this is the first description on the phytochemical constituents of the leaves and rhizomes of A. nilgiricum, which show pharmacological significance, as there has been no literature available yet on GC–MS and phytochemical studies of this plant species. The in silico molecular docking of serverogenin acetate was also performed to confirm its broad spectrum activities based on the binding interactions with the antibacterial, antifungal, antiviral, antioxidant and antidiabetic target proteins. The results of the present study will create a way for the invention of herbal medicines for several ailments by using A. nilgiricum plants, which may lead to the development of novel drugs