Xylanase production by Penicillium chrysogenum (PCL501) fermented on cellulosic wastes

Xylanase production by Penicillium chrysogenum PCL501, newly isolated from wood-wastes, was monitored at 24 h intervals for a period 168 h in media containing four different carbon sources (oatspelt xylan, wheat bran, sawdust, and sugarcane pulp). The highest xylanase activity of 6.47 Units mL-1 was obtained at 96 h in media containing wheat bran whereas media containing sugarcane pulp gave a peak value of 1.39 Units mL-1 at 144 h. Sawdust and xylan gave a peak xylanase activity of 1.35 and 0.79 Units mL-1 respectively at 120 h. Maximum protein released in xylan-containing media was 0.38 mg mL-1. Higher protein yield was obtained in media containing the agro-wastes, with wheat bran giving the highest value of 1.14 mg mL-1. The maximum specific xylanase activities were 2.59, 8.52, 16.06, and 9.36 Units mg Protein -1 for sawdust, sugarcane pulp, wheat bran and xylan respectively. Out of the three agro-wastes used in this study, wheat bran holds the greatest promise for cost-effective production of the xylanase enzyme. The carbon source is the highest inducer of the enzyme in the fungus

Mitragyna ciliata and its trypanocidal activity

The trypanocidal activity of different fractions of hydroethanolic root extract of Mitragyna ciliata Aubrev and Pellegr (Rubiaceae) were evaluated in rats infected with Trypanosoma brucei field isolates from acow. Oral administration of the fractions at a dose of 100 mg/kg for 5 days (10 days post-infection) indicated that only butanol fraction showed trypanocidal activity with inhibition percent of 68.68. Theactivities of oxidative stress enzymes; superoxide dismutase (SOD) and catalase in the infected rats were determined. SOD activity was significantly higher than control (1.64 ± 0.026 I/U) in all fractionsexcept ethyl acetate (1.56 ± 0.031 I/U). Catalase showed a significant decrease in activity in butanol (2.05 ± 0.015 I/U) and chloroform (2.18 ± 0.061 I/U) fractions compared to control (2.30 ± 0.015 I/U). Butanolfraction might have affected the redox equilibrium of the infected animals causing oxidative stress to the parasites. This is the basis of inhibition of growth of the parasites by the butanol fraction

Screening and characterisation of CdTe/CdS quantum dot-binding peptides for material surface functionalisation

Quantum dots (QDs) are promising nanomaterials due to their unique photophysical properties. For them to be useful in biological applications, the particle surface generally needs to be conjugated to biological molecules, such as antibodies. In this study, we screened CdTe/CdS QD-binding peptides from a phage display library as linkers for simple and bio-friendly QD modification. Among five QD-binding peptide candidates, a series of truncated peptides designed from two high-affinity peptides were subjected to an array-based binding assay with QDs to assess their functional core sequences and characteristics. Linking these isolated, shortened peptides (PWSLNR and SGVYK) with an antibody-binding peptide (NKFRGKYK) created dual-functional peptides that are capable of QD surface functionalisation by antibodies. Consequently, the dual-functional peptides could mediate anti-CD9 antibody functionalisation onto CdTe/CdS QD surface; CD9 protein imaging of cancer cells was also demonstrated. Our proposed peptides offer an effective vehicle for QD surface functionalisation in biological applications

Pectinolytic activity of wild-type filamentous fungi fermented on agro-wastes

Five filamentous fungi (Aspergillus clavatus, Aspergillus niger, Fusarium sp., Penicillum chrysogenum and Trichoderma sp.) isolated from agrowaste samples in Lagos metropolis, Nigeria, depolymerized citrus pectin. Best pectolytic activity, as indicated by the diameter of clear, hydrolyzed zones on the medium plates containing commercial citrus pectin as sole carbon source, was obtained with A. niger, closely followed by P. chrysogenum. The two fungi also produced pectinases with different agrowastes (pineapple peel, orange peels, sawdust, sugarcane pulps and wheat bran) as the sole carbon source. The highest pectinase activity by both fungi was produce with wheat bran as the sole carbon source. Peak pectinase activity of 350.28 ± 2.82 and 478.25 ± 3.04 IU mg-1 protein was respectively obtained by submerged fermentation (SmF) at 48 h for A. niger and P.chrysogenum in media containing wheat bran as the sole carbon source. Solid-state fermentation (SSF) yielded higher levels of pectinase activity than the SmF. The strains of A. niger and P. chrysogenum have good prospect for pectinase production. Wheat bran is a good low-cost fermentation substrate for pectinase production by the investigated fungi

Increase of mild disability in Japanese elders: A seven year follow-up cohort study

BACKGROUND: Japan has the highest life expectancy in the world. In a 2002 census government report, 18.5% of Japanese were 65 years old and over and 7.9% were over 75 years old. In this ageing population, the increase in the number of dependent older persons, especially those with mild levels of disability, has had a significant impact on the insurance budget. This study examines the increase of mild disability and its related factors. METHODS: All community-dwelling residents aged 65 and over and without functional decline (n = 1560), of Omishima town, Japan, were assessed in 1996 using a simple illustrative measure, "the Typology of the Aged with Illustrations" to establish a baseline level of function and were followed annually until 2002. The prevalence and incidence of low to severe disability, and their association with chronic conditions present at the commencement of the study, was analyzed. A polychotomous logistic regression model was constructed to estimate the association of each chronic condition with two levels of disability. RESULTS: An increase in mild functional decline was more prevalent than severe functional decline. The accumulation of mild disability was more prominent in women. The major chronic conditions associated with mild disability were chronic arthritis and diabetes in women, and cerebrovascular accident and malignancy in men. CONCLUSION: This study showed a tendency for mild disability prevalence to increase in Japanese elders, and some risk factors were identified. As mild disability increasingly prevalent, these findings will help determine priorities for its prevention in Japanese elders

Enhanced Tubulation of Liposome Containing Cardiolipin by MamY Protein from Magnetotactic Bacteria

Lipid tubules are of particular interest for many potential applications in nanotechnology. Among various lipid tubule fabrication techniques, the morphological regulation of membrane structure by proteins mimicking biological processes may provide the chances to form lipid tubes with highly tuned structures. Magnetotactic bacteria synthesize magnetosomes (a unique prokaryotic organelle comprising a magnetite crystal within a lipid envelope). MamY protein is previously identified as the magnetosome protein responsible for magnetosome vesicle formation and stabilization. Furthermore, MamY is shown in vitro liposome tubulation activity. In this study, the interaction of MamY and phospholipids is investigated by using a lipids-immobilized membrane strip and a peptide array. Here, the binding of MamY to the anionic phospholipid, cardiolipin, is found and enhanced liposome tubulation efficiency. The authors propose the interaction is responsible for recruiting and locating cardiolipin to elongate liposome in vitro. The authors also suggest a similar mechanism for the invagination site in magnetosomes vesicle formation, where the lipid itself contributes further to increasing the curvature. These findings are highly important to develop an effective biomimetic synthesis technique of lipid tubules and to elucidate the unique prokaryotic organelle formation in magnetotactic bacteria

Estruturas de comunidades de animais de solo e sobrevivência dos caracóis terrestres numa ilha do Arquipélago Ogasawara

On Chichijima, one of the Ogasawara (Bonin) Islands located in the Western Pacific Ocean, land snails have declined, the suggested cause being predation pressure by an invasive flatworm (Platydemus manokwari). Soil fauna were investigated in areas where the snail survives, and where it has become extinct. Much of the fauna, dominated by introduced earthworms and ants, was undiminished, however, one undescribed but endemic carabid (Badister sp.), which selectively feeds on land snails, was absent in snail-extinct areas. The invasive flatworm P. manokwari has been reported to feed also on the carcasses of earthworms, as well as on live snails, and is therefore expected to occur in most parts of Chichijima Island. Among other groups, the density of isopods (also dominated by exotic species) was very low, in comparison with the reported ones 30 years ago. Community structure is currently reflected by dominance of earthworms and ants, decline of endemic isopods, and a high frequency of introduced or alien species.Em Chichijima, uma das ilhas do Arquipélago Ogasawara (Bonin), localizado no Oceano Pacífico Ocidental, o número de caracóis terrestres diminuiu, e a causa provável é a predação por uma planária invasora (Platydemus manokwari). A fauna edáfica foi avaliada nas áreas onde o caracol sobreviveu e onde se extinguiu. Grande parte da fauna, dominada inicialmente por minhocas e formigas, não diminuiu; contudo, um carabídeo endêmico e não descrito (Badister sp.), que se alimenta de caracóis terrestres, não estava presente nas áreas em que o caracol foi extinto. Sabe-se que a planária invasiva P. manokwari se alimenta não só das carcaças das minhocas, mas também de caracóis vivos, e por isso habita a maior parte da Ilha Chichijima. Entre outros grupos, a densidade de isópodos (também dominados por espécies exóticas) foi muita baixa, em comparação aos relatos feitos 30 anos antes. A estrutura da comunidade é refletida atualmente pela dominância de minhocas e formigas, declínio de isópodos endêmicos, e uma alta frequência de espécies introduzidas ou exóticas

A Novel Unsupervised Method to Identify Genes Important in the Anti-viral Response: Application to Interferon/Ribavirin in Hepatitis C Patients

Background: Treating hepatitis C with interferon/ribavirin results in a varied response in terms of decrease in viral titer and ultimate outcome. Marked responders have a sharp decline in viral titer within a few days of treatment initiation, whereas in other patients there is no effect on the virus (poor responders). Previous studies have shown that combination therapy modifies expression of hundreds of genes in vitro and in vivo. However, identifying which, if any, of these genes have a role in viral clearance remains challenging. Aims: The goal of this paper is to link viral levels with gene expression and thereby identify genes that may be responsible for early decrease in viral titer. Methods: Microarrays were performed on RNA isolated from PBMC of patients undergoing interferon/ribavirin therapy. Samples were collected at pre-treatment (day 0), and 1, 2, 7, 14 and 28 days after initiating treatment. A novel method was applied to identify genes that are linked to a decrease in viral titer during interferon/ribavirin treatment. The method uses the relationship between inter-patient gene expression based proximities and inter-patient viral titer based proximities to define the association between microarray gene expression measurements of each gene and viral-titer measurements. Results: We detected 36 unique genes whose expressions provide a clustering of patients that resembles viral titer based clustering of patients. These genes include IRF7, MX1, OASL and OAS2, viperin and many ISG's of unknown function. Conclusion: The genes identified by this method appear to play a major role in the reduction of hepatitis C virus during the early phase of treatment. The method has broad utility and can be used to analyze response to any group of factors influencing biological outcome such as antiviral drugs or anti-cancer agents where microarray data are available. © 2007 Brodsky et al