Initial steps of phloroglucinol metabolism in Penicillium simplicissimum

The pathway for the aerobic catabolism of 1,3,5-trihydroxybenzene (phloroglucinol) by a new strain of Penicillium was investigated using both in vivo and in vitro cell-free systems. The fungal strain was isolated by enrichment on phloroglucinol and identified as P. simplicissimum (Oud) Thom. It grew optimally at pH 5.5 and 27°C with 119 mM (1.5%w/v) of phloroglucinol in a basal mineral salts medium. Vapours of the crystalline substrate placed in a Petri-plate lid supported the growth of the fungal colonies on the agar surface. Mycelia grown on phloroglucinol accumulated 1,2,4-trihydroxybenzene and resorcinol in the medium. Washed, resting mycelia grown on phloroglucinol, when resuspended in a buffer utilized oxygen in the presence of catechol, resorcinol, pyrogallol and phloroglucinol. A NADPH-dependent reductase in the cell-free extract reduced phloroglucinol to dihydrophloroglucinol. This electron donor could not be replaced by NADH. Resorcinol hydroxylase, phloroglucinol reductase, catechol-1,2-oxygenase, and catechol-2,3-oxygenase were detected in cell-free extracts of mycelia grown on phloroglucinol. The possible steps in the degradation of phloroglucinol are discussed.     

Water Balance in Cucumis Plants, Measured by Nuclear Magnetic Resonance, I

In this paper we demonstrate the study of plant water balanceby the non-invasive measurement of tissue water content andwater flow using proton nuclear magnetic resonance (NMR). Sapvelocity and flux were measured independently in the presenceof an excess of stationary tissue water. The instrumentationdescribed allows automated and unattended measurement of flow-and water content-variables in a well-defined region of theplant over periods of several days, with a time resolution betweensuccessive measurements of c. 5 s. Using this apparatus theeffect of changes in light intensity (day/night rhythm) andrelative humidity on stem tissue water content as well as onthe velocity and flux of xylem sap in the stem were investigatedin a cucumber plant. The results are in agreement with predictionsfrom a simple model for plant water balance, which is basedon water potential, flow rate and resistance to flow. As longas only transpiration is varied, flow rate and water content(or potential) are affected in opposite ways as demonstratedin this paper. In contrast, the model predicts that changesin uptake (resulting from changes in, for example, root resistance)will induce changes in water content and flow in the same direction.An experimental verification of this prediction is given ina subsequent paper, where, in addition, the NMR results arecompared to those obtained with a dendrometer. Key words: Water balance model, Cucumis sativus L., flow, water content, NMR, water balance measurement     

TASTE GROUP THRESHOLDS AND SENSORY EVALUATION OF SPANISH WINE VINEGARS

Wine vinegar is a product obtained from wine acidification which contains at least 5% by wt. of acetic acid, in general without any additives or colorings.
Aspects studied in this work include: the determination of the taste group thresholds (geometric mean of the individual best-estimate thresholds "BET") of two different acids (citric and acetic acids) in aqueous solution and spanish vinegars produced from table and sherry wines. The results obtained suggest that wine vinegar can be considered something more than just an acidulant agent.
In order to evaluate differences among wine vinegars, discriminant tests for twenty-five spanish vinegars (sherry, table and flavored vinegars) were applied. Six of the twelve attributes freely chosen by assessors allowed grouping of the spanish wine vinegars according to their sensory aspects.     

Arginine deprivation in KB cells: I. Effect on cell cycle progress

When exponentially growing KB cells were deprived of arginine, cell multiplication ceased after 12 h but viability was maintained throughout the experimental period (42-48 h). Although tritiated thymidine ([(3)H]TdR) incorporation into acid-insoluble material declined to 5 percent of the initial rate, the fraction of cells engaged in DNA synthesis, determined by autoradiography, remained constant throughout the starvation period and approximately equal to the synthesizing fraction in exponentially growing controls (40 percent). Continous [(3)H]TdR-labeling indicated that 80 percent of the arginine-starved cells incorporated (3)H at some time during a 48-h deprivation period. Thus, some cells ceased DNA synthesis, whereas some initially nonsynthesizing cells initiated DNA synthesis during starvation. Flow microfluorometric profiles of distribution of cellular DNA contents at the end of the starvation period indicated that essentially no cells had a 4c or G2 complement. If arginine was restored after 30 h of starvation, cultures resumed active, largely asynchronous division after a 16-h lag. Autoradiographs of metaphase figures from cultures continuously labeled with [(3)H]TdR after restoration indicated that all cells in the culture underwent DNA synthesis before dividing. It was concluded that the majority of cells in arginine-starved cultures are arrested in neither a normal G1 nor G2. It is proposed that for an exponential culture, i.e. from most positions in the cell cycle, inhibition of cell growth after arginine with withdrawal centers on the ability of cells to complete replication of their DNA.     

Effect of host plant on cornucopia of mango fruit flies (Diptera: Tephritidae) and their triumphant management in context of climate change

A study was performed to assess the preference of fourteen mango cultivars for fruit flies and their management by bagging. So the choice of Tephritid flies to mango cultivars during fruiting phase is crucial. Fourteen different cultivars of mango viz., ‘Dusehri’, ‘Malda’, ‘Langra’ early cultivars, ‘Chaunsa’, ‘Fajri Klan’, ‘Sensation’ medium whereas ‘Sanglakhi’, ‘Retaul-12’, ‘Mehmood Khan’, ‘Tukhmi’, ‘Kala Chaunsa’, ‘Chitta Chaunsa’, ‘Dai Wala’ and ‘Sobey De Ting’ late cultivars were assessed for their suitability for fruit flies. The results indicate that the population density of fruit flies was higher on late cultivars like ‘Sanglakhi’ (20.61 percent), ‘Mehmood Khan’ (20.22 percent) and ‘Reutal-12’ (19.92 percent) were proved to be highly susceptible to fruit flies. Among these the cultivar ‘Reutal-12’ was selected being commercial and future cultivar for the management of fruit flies through bagging. The results reported that the attack of tephritid fruit flies and other insect pests were zero in bagged fruits as compared with control. It was further recorded that the bagged fruits has maximum average fruit weight i.e. 203.50 and 197.83 g per fruit was noted in those treatments where butter paper bag and brown paper bag was wrapped with better coloration as compared with un-bagged fruit with 159.5 g per fruit. Similarly, on an average fruit length were more i.e. 90.17, 91.33 mm in bagged fruit and 85.33 in un-bagged fruits. Furthermore, bagged fruits have zero incidence of disease with reduced fruit crack, fruit sunburn, mechanical damage, bird damage, fruit blemished and agrochemical residues on the fruit. So, it is concluded that the special attention should be given on ‘Reutal-12’ for the management of fruit flies when devising an IPM program for the control of fruit flies. Further, bagging has proved to be the good agricultural practices for the production of quality mango.     

Viral impacts on honey bee populations: A review

Honey bee is vital for pollination and ecological services, boosting crops productivity in terms of quality and quantity and production of colony products: wax, royal jelly, bee venom, honey, pollen and propolis. Honey bees are most important plant pollinators and almost one third of diet depends on bee’s pollination, worth billions of dollars. Hence the role that honey bees have in environment and their economic importance in food production, their health is of dominant significance. Honey bees can be infected by various pathogens like: viruses, bacteria, fungi, or infested by parasitic mites. At least more than 20 viruses have been identified to infect honey bees worldwide, generally from Dicistroviridae as well as Iflaviridae families, like ABPV (Acute Bee Paralysis Virus), BQCV (Black Queen Cell Virus), KBV (Kashmir Bee Virus), SBV (Sacbrood Virus), CBPV (Chronic bee paralysis virus), SBPV (Slow Bee Paralysis Virus) along with IAPV (Israeli acute paralysis virus), and DWV (Deformed Wing Virus) are prominent and cause infections harmful for honey bee colonies health. This issue about honey bee viruses demonstrates remarkably how diverse this field is, and considerable work has to be done to get a comprehensive interpretation of the bee virology.     

Partial cloning and production of polyclonal antiserum against recombinant capsid protein of Hepatopancreatic Parvovirus (HPV) and its application for diagnostics in penaeid shrimp

Hepatopancreatic Parvovirus (HPV) causes infection in the early stages of shrimp leading to retarded growth, ultimaltely resulting in monetary loss to the shrimp farmers. To over come this situation screening of post-larvae (PL) by immunology-based diagnostics is required. Hence, the specific gene of capsid protein for HPV was cloned into pRSET B expression vector and rHCP overexpressed with 6-histidine tagged fusion protein in Escherichia coli BL21(DE3). Immunology-based methods like Western blot, dot blot and ELISA techniques were employed to detect HPV in infected samples using the antiserum raised in rabbits against recombinant HCP of HPV. The dot blot assay using anti-rHCP was found to be capable of detecting HPV in HPV infected post-larvae as early as at 24 h post infection. The antiserum could detect the HPV in the infected samples at 1 ng of total protein. HPV infection estimated by ELISA using anti-HCP and pure r-HCP as a standard was found to increase gradually during the course of infection from 24 h post infection. The sensitivity of antibody-based diagnostics employed in the present study was compared with that of PCR diagnostic method to screen the post-larvae for the detection of HPV.     

Estimation of Jordanian isolated Pectobacterium cellulase,pectinase concentrations,RAPD polymorphism and their maceration activity

Forty-two Pectobacterium isolates were recovered from contaminated soil and rotted vegetables in Jordan. Twenty of them were belonged to; Pectobacterium carotovorum subsp. Carotovorum (Pbc) (= Erwinia carotovora subsp. carotovora), 11 isolates were belonged to Pectobacterium atrospeticum (= Erwinia carotovora subsp. atroseptica) (Pba) and 11 isolates were not classifiable (Pbs). Maceration activity of the 42 proved their ability to macerate potato, carrot and radish slices. Maceration activity of the isolates either of the same subspecies or in between the isolates of different subspecies isolated from the same host or from different hosts was varied. The measured concentration in μM?ml^?1 of both cellulase and pectinase enzymes was variable too. The Rapid amplified polymorphic DNA-PCR finger printing of total genomic DNA using a pair of 10-mer oligonucleotide primers amplification showed similar DNA bands with some polymorphic variations amongst the isolates.