In the present study, we tested the antioxidant activity of phycoerythrin (PE, an oligomeric light harvesting protein isolated from Lyngbya sp. A09DM) to curtail aging effects in Caenorhabditis elegans. Purified PE (100 μg/ml) dietary supplement was given to C. elegans and investigated for its anti-aging potential. PE treatment improved the mean life span of wild type (N2)-animals from 15±0.1 to 19.9±0.3 days. PE treatment also moderated the decline in aging-associated physiological functions like pharyngeal pumping and locomotion with increasing age of N2 worms. Moreover, PE treatment also enhanced the stress tolerance in 5-day-aged adults with increase in mean survival rate from 22.2±2.5 to 41.6±2.5 % under thermo stress and from 30.1±3.2 to 63.1±6.4 % under oxidative (hydrogen peroxide)-stress. PE treatment was also noted to moderate the heat-induced expression of human amyloid-beta(Aβ 1-42 ) peptide and associated paralysis in the muscle tissues of transgenic C. elegans CL4176 (Alzheimer's disease model). Effectiveness of PE in expanding the life span of mutant C. elegans, knockout for some up (daf-2 and age-1)-and down (daf-16)-stream regulators of insulin/IGF-1 signaling (IIS), shows the independency of PE effect from DAF-2-AGE-1-DAF-16 signaling pathway. Moreover, the inability of PE in expanding the life span of hsf-1 knockout C. elegans(sy441) suggests the dependency of PE effect on heat shock transcription factor (HSF-1) controlling AGE (2014) stress-induced gene expression. In conclusion, our results demonstrated a novel anti-aging activity of PE which conferred increased resistance to cellular stress resulting in improved life span and health span of C. elegans.

Aging is a process of progressive decline in physiological functions resulting in increased vulnerability to diseases and death. Aging results in increased rates of age related disorders like neurodegenerative diseases, cardiovascular diseases, diabetes, cancer, arthritis etc. Modulation of insulin signaling, protein aggregation, stress, free radical damage and inflammation are the major causes for deleterious changes resulting in aging. Many studies are being undertaken to find novel compounds which can improve a typical human life span and aid in healthy aging. We investigated the potential of one such compound silymarin for its anti-aging effect. Silymarin is a flavanone derivative extracted from the seeds of the milk thistle Silybum marianum. It is widely used for the treatment of liver diseases in clinical practice. We tested the anti-aging efficacy of silymarin using the Caenorhabditis elegans model system. Our results demonstrate that C. elegans treated with 25μM and 50μM silymarin concentration resulted in an increase in mean lifespan by 10.1% and 24.8% respectively compared to untreated control. Besides increased lifespan, silymarin treated aged animals showed better locomotion rate, higher response to stimuli and improved tolerance to stress compared to untreated control. We also checked the potential of silymarin to slow the progression of neurodegenerative disorder like Alzheimer's disease (AD) by using CL4176 C. elegans model for AD. C. elegans CL4176 transgenic animal induces expression of amyloid beta-protein (Aβ1-42) in muscle tissues when subjected to temperature of 23°C and above resulting in worm paralysis. CL4176 animals treated with silymarin showed delayed paralysis via enhancing resistance to oxidative stress. These results suggested that silymarin is a potential hormetin for preventing aging and age-related diseases.

No abstract

Actinomycetes are a gram-positive, filamentous subgroup of bacteria most known for antibiotic production. In fact, most of the antibiotics available today have originated from actinomycetes, namely from the genus Streptomyces. Novel bacteria with antimicrobial activities have been discovered from bacterial screen studies for decades and there is still much more yet to be unearthed. One hundred seventy five strains of actinomycetes were isolated from 38 different soil samples from different locations in Patna, India. Potential antibiotic producers were screened against four test microorganisms (Escherichia coli MTCC 739, Staphylococcus aureus MTCC 96, Streptomyces lividans TK23 MTCC 4 and Candida albicans MTCC 227). The bioassay revealed that about 26% of actinomycetes isolates were active against at least one of the test microorganism. Characterization of a selected isolate has led to identification of a unique strain of actinomycetes (MP 525) showing broad-spectrum antibacterial and antifungal properties. The strain MP 525 has been morphologically characterized as Streptomyces sp. and deposited at MTCC, Chandigarh, India with accession number 8723. The 16S rRNA gene of the strain Streptomyces sp. US7 MTCC 8723 was sequenced and the DNA sequence was deposited at NCBI, Bethesda (GenBank accession. No. HQ659005). On the basis of λmax values of culture filtrates, it has been suggested that the strain might be producing LL-E19085-like antibacterial and a flavone glycoside-like antifungal antibiotics, which can be further exploited for industrial and biological applications.

No abstract