Antimicrobial activities of chitosan and calcium chloride on in vitro growth of Colletotrichum gloeosporioides from papaya

The antimicrobial activities of chitosan and calcium chloride (CaCl2) on the growth, spore germination, and hyphal morphology of Colletotrichum gloeosporioides, isolated from naturally infected papaya fruits, was investigated in in vitro studies. Chitosan was found to inhibit the radial growth and spore germination of the fungus significantly at higher concentrations. Radial growth was inhibited by 52 and 82% with 0.75 and 1% chitosan, respectively. Spore germination was completely inhibited in Potato Dextrose Agar (PDA) medium containing 0.5% and above chitosan concentrations. Light microscope observations showed that chitosan induced morphological changes, including abnormal branching, swelling hyphal tips, vacuolation and distortion. Calcium chloride at 1 to 4% had no pronounced effects on mycelial growth inhibition. However, PDA amended with 3 and 4% CaCl2 significantly (P≤0.05) inhibited about 26% of spore germination relative to the control. Findings from these experiments demonstrated that chitosan has suppressive activity against C. gloeosporioides of papaya and could be used as part of a disease management program. Nevertheless, to a lesser extent, CaCl2 can also be included as part of the program

Investigation on the Natural Enemies of Jute Yellow Mite and Their Performances and Seasonal Incidence

The jute yellow mite Polyphagotarsonemus latus constitutes one of the major pests of jute crop in Bangladesh. The objective of this work was to investigation on the natural enemies of jute yellow mite. The investigation on the natural enemies of jute yellow mite were studied in the laboratory of Bangladesh Jute Research Institute during March 2011 to September 2013. As many as six predators of jute yellow mite viz, Predatory mite, Thrips, Minute pirate bug, Lady bird beetle, Mirid bug and Spider were collected and identified. The predation rate of the predatory mite Amblyseius sp. showed an average of 8.8 jute yellow mite per hour in laboratory condition. Predatory mite reached the peak on the 20th June. The highest population was 25 predatory mite/25 leaves. The population of predatory mite declined sharply in the 1st week of July. The nymph and adult of Scolothrips consumed an average of 15.4 and 20.10 yellow mite per hour. Scolothrips sp reached its peak population on 30th June and declined occurred in the 1st week of July. Both nymph and adult stage of Orius sp. predate 24.5 and 21 jute yellow mite respectively. The highest number of Minute pirate bug 20 was recorded at 30th June. Both the grubs and adults of lady bird beetle predate on all the stage of yellow mite. Grub was found as voracious feeder showing a predation efficiency of 35 per hour. The highest and lowest number of Ladybird beetle was recorded on 25th June and 5th May respectively. The highest 15 Mirid bug was recorded at 30th June. An unidentified species of spider was found to consume yellow mite

A Peptide of SPARC Interferes with the Interaction between Caspase8 and Bcl2 to Resensitize Chemoresistant Tumors and Enhance Their Regression In Vivo

SPARC, a matricellular protein with tumor suppressor properties in certain human cancers, was initially identified in a genome-wide analysis of differentially expressed genes in chemotherapy resistance. Its exciting new role as a potential chemosensitizer arises from its ability to augment the apoptotic cascade, although the exact mechanisms are unclear. This study further examines the mechanism by which SPARC may be promoting apoptosis and identifies a smaller peptide analogue with greater chemosensitizing and tumor-regressing properties than the native protein. We examined the possibility that the apoptosis-enhancing activity of SPARC could reside within one of its three biological domains (N-terminus (NT), the follistatin-like (FS), or extracellular (EC) domains), and identified the N-terminus as the region with its chemosensitizing properties. These results were not only confirmed by studies utilizing stable cell lines overexpressing the different domains of SPARC, but as well, with a synthetic 51-aa peptide spanning the NT-domain. It revealed that the NT-domain induced a significantly greater reduction in cell viability than SPARC, and that it enhanced the apoptotic cascade via its activation of caspase 8. Moreover, in chemotherapy resistant human colon, breast and pancreatic cancer cells, its chemosensitizing properties also depended on its ability to dissociate Bcl2 from caspase 8. These observations translated to clinically significant findings in that, in-vivo, mouse tumor xenografts overexpressing the NT-domain of SPARC had significantly greater sensitivity to chemotherapy and tumor regression, even when compared to the highly-sensitive SPARC-overexpressing tumors. Our results identified an interplay between the NT-domain, Bcl2 and caspase 8 that helps augment apoptosis and as a consequence, a tumor's response to therapy. This NT-domain of SPARC and its 51-aa peptide are highly efficacious in modulating and enhancing apoptosis, thereby conferring greater chemosensitivity to resistant tumors. Our findings provide additional insight into mechanisms involved in chemotherapy resistance and a potential novel therapeutic that specifically targets this devastating phenomenon

Ultrastructural studies of soybean seed-borne infection by Diaporthe phaseolorum var. sojae and screening of antagonistic potentiality by selected biocontrol agents in vitro

The association of Diaporthe phaseolorum var. sojae with soybean seed decay was examined by ultrastructural studies using light microscopy and scanning electron microscopy. The fungus was detected over the seed surface as whitish-grey mycelial growth and scattered black pycnidia. Hyphae and pycnidia were also observed in palisade, hourglass and parenchyma cell layers of the seed coat. Mycelial growth of D. phaseolorum var. sojae was abundant in the hourglass cell layer compared with other layers of the seed coat. Neither mycelium nor pycnidium was found in any tissues of the cotyledon and embryo of the infected seed. Asymptomatic seeds were free from infections. Artificial seed inoculation with D. phaseolorum var. sojae significantly reduced seed germination over control by 21.2% and increased seed rot by 120% in sterilized soil under glass house conditions. Six isolates of Trichoderma and three isolates of bacteria were tested in vitroagainst D. phaseolorum var. sojae in dual culture test. Among these organisms, T. harzianum isolate UPM40 exhibited the most antagonistic potential based on Percent Inhibition Radial Growth (PIRG) of 92.9% and shortest time needed (7 days) to overgrow the D. phaseolorum var. sojae colony as compared to other tested isolates

Antagonistic potential of selected fungal and bacterial biocontrol agents against Colletotrichum truncatum of soybean seeds

Ten fungal and bacterial biocontrol agents (BCAs) were evaluated in vitro for their antagonistic potential against Colletotrichum truncatum isolated from soybean seeds. Two fungal BCAs namely Trichoderma virens isolate UPM23 and Trichoderma harzianum isolate UPM40 and a bacterial BCA namely Pseudomonas aeruginosa isolate UPM13B8 strongly inhibited the growth of C. truncatum based on high PIRG values in dual culture and culture filtrate tests. Studies on the mechanism of action using mycoparasitism technique and antibiosis observed under light microscope revealed that T. virens and T. harzianum inhibited the growth of C. truncatum by coiling and penetration into the hyphae. Consequently, the hyphae of C. truncatum became malformed and swollen. Pseudomonas aeruginosa also caused mycelial malformation; the mycelia turned vacuoled and swollen in or at tips of hyphae. Pseudomonas aeruginosa gave the highest PIRG value in the culture filtrate test, suggesting that antibiosis could be the main mechanism of antagonism. No inhibitory effect was observed on soybean seeds and seedlings when the seeds were artificially inoculated with T. virens, T. harzianum and P. aeruginosa. On the contrary, T. virens and T. harzianum were found to enhance seed germination and seedling establishment, while P. aeruginosa enhanced fresh and dry weights of seedlings

Bacterial reduction of hexavalent molybdenum to molybdenum blue.

A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such as Serratia marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium, silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at 1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation

Analysis of Toyota’s Marketing Strategy in the UK Market

This is a study on Toyota automobile industry, especially on Toyota GB Plc. The work mainly focuses on the strengths and weaknesses as well as the company’s way of keeping competitive advantage. The purpose of the study is to explore the marketing strategy of Toyota GB Plc. in UK market. It is an explorative study in nature. Both primary and secondary data are used to get the insights about the market. The study concludes with the understanding and recommendation of how Toyota’s marketing mix is contributing to obtain a substantial market share and brand image for its innovative technology. Key words: customer, marketing mix, strategy, innovatio

Analysis of Toyota’s marketing strategy in the UK market

Vol.5, No.20, 2013

Protective Roles of Some Leafy and Non-leafy Vegetables against the Severity of Arsenic-induced Skin Lesions among Women Living in Rural Bangladesh: A Case Control Study

Arsenicosis is common among villagers as they drink more contaminatedwater since the arsenic-crisis in Bangladesh. Supplementation of vitamins and micronutrients in counteracting arsenic toxicity has been proved for arsenic treatment. This study was intended to assess protective and beneficial roles of some commonly eaten vegetables on the development and severity of arsenicinduced skin lesions. A case-control study among (N=122) adult rural-women (62 cases had various forms of arsenical skin-lesions e.g. melanosis/keratosis/ mixed-lesions and 60 sex-age-matched healthy-controls) was conducted in Shaharstee Upazilla of Chandpur district, Bangladesh. Socio-demographic data recorded in a pre-tested-questionnaire, ‘per-day vegetables ingestion’ of cases and controls were measured qualitative and quantitatively (24-hour recall-methods, food-frequency/week and food history-record/week). Multiple logistic regression/MLR analyses were performed to find out protective roles of some dietary leafy-vegetables/LVs and non-leafy vegetables/NLVs on arsenicosis and their influences on the degree of severity of arsenicosis also determined. Abstinence from taking some LVs/NLVs among cases than controls is associated with increased risk for arsenicosis (P<0.05). Amongst all most-frequently eaten vegetables (n=17) per day Momordica diocia has the highest skin protective role on arsenicosis [Adjusted odds ratio/AOR 8.2, 95% CI (2.11-31.9), P=<0.01], followed by Ipomoea acquatica (AOR:7.3), Basella alba (AOR:6.2), Solanum tuberosum (AOR:4.0), Vigna unguiculata sesquipedalis (AOR:3.2), Trichosanthes anguina (AOR:1.2) and Abelmoschus esculentus (AOR:1.2). Moreover, severe skin lesion was observed as compared to non-severe cases (mild/moderate) for less intake frequencies of vegetables. This study outlined that commonly eaten vegetables have protective and beneficial roles on arsenic-induced skin lesions. Large samples longitudinal study of this important field of therapeutic-intervention is warrante