The bactericidal effects of Lactobacillus acidophilus,garcinol and Protykin® compared to clarithromycin,on Helicobacter pylori

Chronic infection with Helicobacter pylori causes peptic ulcers, gastric cancer and lymphoma. We evaluated the inhibitory effects of the probiotic Lactobacillus acidophilus DDS-1J, the antibiotic clarithromycin and the natural antioxidants garcinol and Protykin^® (containing 50% trans-resveratrol) on Helicobacter pylori strain ATCC 49503. The findings of this study indicate that Lactobacillus acidophilus DDS-1J exerts a growth inhibitory effect on H. pylori at a ratio of 1:1 or higher in vitro. In the case of clarithromycin, garcinol and resveratrol, the bactericidal effect is time and concentration dependent. Clarithromycin completely inhibited growth at 62.5 g/ml at 6 h and at 31.5 g/ml at 12 h. For garcinol the highest concentration needed for complete inhibition was 31.5 g/ml at 6 h and 3.9 g/ml after 12 h incubation. For resveratrol, significant inhibition was noted at 1000 g/ml at 12 h only. The bactericidal effect of garcinol was reduced by the addition of resveratrol at all concentrations 125 g/ml at 6 and 12 h. We conclude from this study that Lactobacillus acidophilus DDS-1J inhibits H. pylori at 1:1 and higher ratios. Also, between the two antioxidants, garcinol is much more potent than resveratrol as a bactericidal agent against H. pylori, and that resveratrol may antagonize this effect. Finally, our study showed equivalent or better bactericidal activity of garcinol compared to clarithromycin against H. pylori at 6 and 12 h incubation, indicating a potential role for this antioxidant in treatment for H. pylori infection.     

Synthesis of some new steroidal [16alpha,17alpha-d]-isoxazolines

Regioselective synthesis of novel steroidal anti-inflammatory ante drug analogues, viz., [16alpha,17alpha-d]-isoxazolines 1(a-h) and 2(a-h) prepared in a single step in good yield by the reaction of 16-dehydropregnenolone acetate (16-DPA) 1 or related 21-chloro-20-oxopregnane 2 with various aldoximes (a-h) in presence of chloramine-T in refluxing ethanol.     

Artificial citrate operon and Vitreoscilla hemoglobin gene enhanced mineral phosphate solubilizing ability of Enterobacter hormaechei DHRSS

Mineral phosphate solubilization by bacteria is mediated through secretion of organic acids, among which citrate is one of the most effective. To overproduce citrate in bacterial systems, an artificial citrate operon comprising of genes encoding NADH-insensitive citrate synthase of E. coli and Salmonella typhimurium sodium-dependent citrate transporter was constructed. In order to improve its mineral phosphate solubilizing (MPS) ability, the citrate operon was incorporated into E. hormaechei DHRSS. The artificial citrate operon transformant secreted 7.2 mM citric acid whereas in the native strain, it was undetectable. The transformant released 0.82 mM phosphate in flask studies in buffered medium containing rock phosphate as sole P source. In fermenter studies, similar phenotype was observed under aerobic conditions. However, under microaerobic conditions, no citrate was detected and P release was not observed. Therefore, an artificial citrate gene cluster containing Vitreoscilla hemoglobin (vgb) gene under its native promoter, along with artificial citrate operon under constitutive tac promoter, was constructed and transformed into E. hormaechei DHRSS. This transformant secreted 9 mM citric acid under microaerobic conditions and released 1.0 mM P. Thus, incorporation of citrate operon along with vgb gene improves MPS ability of E. hormaechei DHRSS under buffered, microaerobic conditions mimicking rhizospheric environment.     

Role of Cbl-PI3K Interaction during Skeletal Remodeling in a Murine Model of Bone Repair

Mice in which Cbl is unable to bind PI3K (YF mice) display increased bone volume due to enhanced bone formation and repressed bone resorption during normal bone homeostasis. We investigated the effects of disrupted Cbl-PI3K interaction on fracture healing to determine whether this interaction has an effect on bone repair. Mid-diaphyseal femoral fractures induced in wild type (WT) and YF mice were temporally evaluated via micro-computed tomography scans, biomechanical testing, histological and histomorphometric analyses. Imaging analyses revealed no change in soft callus formation, increased bony callus formation, and delayed callus remodeling in YF mice compared to WT mice. Histomorphometric analyses showed significantly increased osteoblast surface per bone surface and osteoclast numbers in the calluses of YF fractured mice, as well as increased incorporation of dynamic bone labels. Furthermore, using laser capture micro-dissection of the fracture callus we found that cells lacking Cbl-PI3K interaction have higher expression of Osterix, TRAP, and Cathepsin K. We also found increased expression of genes involved in propagating PI3K signaling in cells isolated from the YF fracture callus, suggesting that the lack of Cbl-PI3K interaction perhaps results in enhanced PI3K signaling, leading to increased bone formation, but delayed remodeling in the healing femora.     

Broad-host-range plasmid-mediated metabolic perturbations in Pseudomonas fluorescens 13525

Genetic engineering of fluorescent pseudomonads for various industrially, agriculturally and environmentally important bioprocesses often involves the use of suitable plasmids. Plasmid-mediated alterations in host physiology and metabolism are poorly understood for this group of organisms. Thus, we investigated the metabolic perturbations in Pseudomonas fluorescens 13525 due to the independent and combined presence of broad-host-range plasmids, pBBR1MCS-2 (copy number 30) and pUCPM18 derived pAB4 and pAB8 (copy number 14-16). Presence of pAB4 and pAB8 not only significantly increased the growth rate and glucose utilization of P. fluorescens 13525, but also increased glucose dehydrogenase activity and gluconic acid production indicating enhanced direct oxidative pathway for glucose catabolism. Additionally, increased secretion of pyruvic, acetic, and citric acids caused faster media acidification in presence of pAB4 and pAB8. Simultaneous presence of pAB4/pAB8 in Pf (pAB48) and pAB4/pBBR1MCS-2 in Pf (pAB4BBR1MCS-2) reduced their respective copy numbers to nearly half. Pf (pAB48) demonstrated further increase in direct oxidation pathway without altering growth and glucose depletion rates, as compared with single transformants. Conversely, pBBR1MCS-2 plasmid did not greatly alter P. fluorescens 13525 metabolism when present independently but masked the effects imposed by pAB4 when present in its combination. In conclusion, P. fluorescens 13525 redesigns its metabolism in response to the presence of plasmids irrespective of their nature, by enhancing anaplerosis with a simultaneous reduction in catabolism as indicated by increased pyruvate carboxylase and decreased citrate synthase activities, respectively. Such information will be helpful for vector designing during genetic engineering of fluorescent pseudomonads.     

Anthocyanin production in a callus line of <Emphasis Type="Italic">Panax sikkimensis</Emphasis> Ban

A root-derived callus line of Panax sikkimensis that stably accumulates anthocyanins was established by small cell aggregate selection method. The selected line showed a growth index of 221.36 and an anthocyanin content of 2.76 mg/g fw (7.076% dw) in 50–60 d of growth on a modified MS medium containing 4.5 μM 2,4-dichlorophenoxy acetic acid and 1.2 μM kinetin under 16-h light and 8-h dark photoperiodic conditions. Incubation under continuous light increased the growth index to 435.57 but led to a marginal dilution of anthocyanin content to 2.192 mg/g fw (6.928% dw). The purple-red pigment had absorption maximum at 528 nm. The selected callus line has shown sustained growth and productivity for more than 6 yr now. Interestingly, pigment accumulation in the selected line did not hinder the ginsenoside production in the callus tissue (0.9–1.2% fw).     

Phytochemical analysis of <Emphasis Type="Italic">Andrographis paniculata</Emphasis> extract and its antimicrobial activity

The present study describes the phytochemical profile and antimicrobial activity of Andrographis paniculata. For the present investigation, two samples of A. paniculata extracts, obtained by extraction in chloroform and chloroform + HCl, respectively, were compared for their antimicrobial activity and further subjected to GC-MS analysis to find out the nature of the compounds responsible for the antimicrobial activity. The antibacterial activities were assessed by measuring the diameter of the inhibition zones, MIC and MBC values. Compared to the chloroform + HCl extract, the chloroform extract showed better antimicrobial activity against all the nine pathogenic bacterial strains tested. The chloroform extract was observed to be active against the opportunistic and pathogenic gram-negative bacteria, indicating its potential application related to noscomial infections. GC-MS results revealed phenols, aromatic carboxylic acids and esters in the chloroform extract to be the molecules responsible for the antimicrobial activity of A. paniculata. This is the first report on analysis of antimicrobial components from A. paniculata, and our results confer the utility of this plant extract in developing a novel broad spectrum antimicrobial agent.     

Role of traditional knowledge in marine bioprospecting

The “marine world” is endowed with diverse life forms. The life under the oceans is bestowed with a unique gene pool and characteristics owing to extreme conditions such as high salt concentration and temperature variations. The marine biodiversity is an extremely rich resource for the development of a wide array of applications in food, pharmaceuticals, cosmetics. Various forms of traditional knowledge, including traditional medicinal knowledge, have been silently developing over the centuries, with the coastal tribes in nations across the globe. Unfortunately, marine traditional knowledge has been underestimated both commercially and legally. It has still not gained its due importance at the international platform for sustainable use and development. An attempt has been made in the present study to collate information on marine traditional knowledge based medicine. Recent trends of marine bioprospecting by various nations including India have been discussed, followed by the study of legal provisions dealing with marine bioprospecting that aim at conservation and sustainable use of marine biodiversity and associated traditional knowledge. Convention of Biological Diversity, United Nations Convention on the Law of the Seas and World Intellectual Property Organization are the major international legal instruments that discuss the concepts of Prior Informed Consent, access and benefit sharing with regard to biopiracy and provide guidelines and limits for conducting marine scientific research.     

Targeted sequencing of the 9p21.3 region reveals association with reduced disease risks in Ashkenazi Jewish centenarians

Genome-wide association studies (GWAS) have pinpointed the chromosomal locus 9p21.3 as a genetic hotspot for various age-related disorders. Common genetic variants in this locus are linked to multiple traits, including coronary artery diseases, cancers, and diabetes. Centenarians are known for their reduced risk and delayed onset of these conditions. To investigate whether this evasion of disease risks involves diminished genetic risks in the 9p21.3 locus, we sequenced this region in an Ashkenazi Jewish centenarian cohort (centenarians: n = 450, healthy controls: n = 500). Risk alleles associated with cancers, glaucoma, CAD, and T2D showed a significant depletion in centenarians. Furthermore, the risk and non-risk genotypes are linked to two distinct low-frequency variant profiles, enriched in controls and centenarians, respectively. Our findings provide evidence that the extreme longevity cohort is associated with collectively lower risks of multiple age-related diseases in the 9p21.3 locus.