International Journal of Histology and Cytology

International Journal of Histology and Cytology ISSN 2447-9535 Vol. 5 (6), pp. 439-444, June, 2018. © International Scholars Journals

Full Length Research Paper

A study of enzymatic hydrolysis of lignocellulosic material saw dust

P. B. Acharya¹, D. K. Acharya¹* and H. A. Modi²

¹Department of Microbiology, Biogas Research Centre, Gujarat Vidyapith, Sadra, Gandhinagar, Gujarat, India.

²Department of Life Science, School of Sciences, Gujarat University, Ahmedabad-380009, Gujarat, India.

*Corresponding author. E-mail: [email protected], Telephone and Fax: +91-79-23274274.

Accepted 07 April, 2017

Abstract

Cellulases are a group of hydrolytic enzymes and are capable of degrading lignocellulosic materials. Cellulases have wide range of applications. This work focuses on factors relevant for improvement of enzymatic hydrolysis of saw dust by using Aspergillus niger. Different cultural conditions were examined to assess their effect in optimizing enzyme production. Alkaline pretreated (2 N NaOH) saw dust at 9.6% concentration gave 0.1813 IU/mL cellulase activity. Optimum pH for cellulase production was between 4.0 and 4.5. Submerged fermentation at 120 rpm at 28°C gave higher yields of cellulase compared to static condition. Several other parameters like inoculum size, time duration, nitrogen source and its concentration were also optimized for the cellulase production by using saw dust as substrate.

Key words: Cellulase, Aspergillus niger, lignocelluloses, saw dust.

International Journal of Histology and Cytology ISSN 2447-9535 Vol. 5 (4), pp. 409-414, April, 2018. © International Scholars Journals

Full Length Research Paper

A study of local fungal isolate capable of hydrolyzing HEC in the pseudoplastic paint

Amani M. D. El Ahwany¹* and Eman A. H. Mohamed²

¹Faculty of Science, Botany Department, Alexandria University, Alexandria, Egypt.

²Faculty of Science, Botany Department, Alexandria University (Damanhour Branch), Alexandria, Egypt.

*Corresponding author. E-mail: [email protected].

Accepted 19 July, 2017

Abstract

A pseudoplastic paint manufactured by the Protal Paint Company in Alexandria, Egypt was examined for its quality to resist microbial degradation. The paint was hydrolyzed by extracellular endoglucanase of a local fungal isolate. The main hydrolysed component was the hydroxylethyl cellulose (HEC) thickener. The fungal isolate was identified as Aspergillus niger which showed a DNA monomorphism of 86% to A. niger ATCC 16404 by RAPD. A Plackett–Burman design was performed to determine the factors influencing endoglucanase activity. The analysis revealed the significance of negative effect of glucose concentration on endoglucanase specific activity.

Key words: Hydroxylethyl cellulose, Aspergillus niger, endoglucanase, Plackett-Burman.

International Journal of Histology and Cytology ISSN 2447-9535 Vol. 5 (5), pp. 415-422, May, 2018. © International Scholars Journals

Full Length Research Paper

Cellular and molecular mechanism associated with anticancer activity of Commelina benghalensis

Vusi G. Mbazima¹, Matlou P. Mokgotho¹, Faghri February², D Jasper G. Rees² and Leseilane J. Mampuru¹*

¹Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo (Turfloop campus), Private Bag X1106, Sovenga, 0727, Limpopo Province, Republic of South Africa. ²Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville, 7535, Cape Town, Republic of South Africa.

*Corresponding author. E-mail: [email protected]. Tel. +27-15-268-3018. Fax. +27-15-268-3234.

Accepted 09 February, 2017

Abstract

Stem extracts of Commelina benghalensis (Linn.), although not extensively documented, are frequently used in traditional medicine for the treatment of ailments such as skin malformations and outgrowths. Accordingly, the study was aimed to investigate possible molecular mechanisms that are associated with the potential anti-carcinogenic property of this agrofield weed. Jurkat T cells were exposed to different concentrations (0-600 µg/ml) of the crude methanolic extract of C. benghalensis to evaluate their growth inhibitory and apoptosis inducing effects. The extract elicited a dose- and time-dependent inhibition of cell proliferation, followed by a concomitant decrease in cell viability. The observed cytotoxicity was linked to the induction of apoptosis as determined by morphological and biochemical features known to be associated with the advent of apoptosis. Real time quantitative RT-PCR and Western blot analyses of Bax, Bcl-2 and p53 exhibited aberrant expression profiles of these genes under various treatment conditions. Taken together, the data suggest that the crude methanolic extract of C. benghalensis contains bioactive compounds that may be beneficial in the treatment of malignant growths, and that this apparent antineoplastic activity is a consequence of dysregulated expression of apoptosis-responsive genes. These observations could provide a credible scientific justification upon which the ethnopharmacological utilisation of C. benghalensis is founded.

Key words: Apoptosis, Bcl-2, Bax, p53, Commelina benghalensis; Jurkat T cells.

International Journal of Histology and Cytology ISSN 2447-9535 Vol. 5 (1), pp. 368-374, January, 2018. © International Scholars Journals

Full Length Research Paper

Effect of substrate pre-treatment using acid and alkali at two different concentrations

Damisa, D.¹*, Ameh, J. B.² and Umoh, V. J.²

¹Section of Microbiology, Department of Applied Science, Kaduna Polytechnic, PMB 2021, Kaduna, Nigeria.

²Department of Microbiology, Ahmadu Bello University, Zaria, Nigeria.

*Corresponding author. E-mail: [email protected], +2348023348264.

Accepted 09 March, 2017

Abstract

Lignocellulosic biomass holds remarkable potential for conversion into commodity products presenting dual advantage of sustainable resource supply and environmental quality. Though their utilization does not compete with food and feed demand, its bioconversion and utilizability is facilitated by pretreatment. The effect of the substrate pre-treatment using acid and alkali at two different concentrations (0.5 and 2 M) for two different residence timings (1 and 3 h) on cellulase production from corncob, corn straw and bagasse was studied using Aspergillus niger AH3. The strain was inoculated into 10 g/L of the processed pre-treated lignocellulosic substrates previously added to batches of the Mandels basal medium. The pH of the medium was adjusted to optimum (4.8) and the flasks with the contents autoclaved, thereafter fermentation begun. Samples of each flask were taken aseptically at regular interval (24 h) throughout the growth phase until the enzyme activity peaked off (between 110 and 170 h), centrifuged and the clear supernatant was used for the enzyme assay. Enzyme expression in all the pretreated biomass increased steadily from day one and peaked off at day four or five for the alkali pretreated residues whereas it was at day six for acid pretreated residues. Generally for the alkali treated residues irrespective of residence time, maximum cellulase yield was at day 5 while for the acid treated residues, maximum cellulase yield was at day 6. Enzyme yield from residues treated for longer period (3 h) using alkali when compared to those using acid under the same condition of fermentation was highly significant. The alkali treated residues showed higher cellulase yield than the acid treated residues. Highest cellulase activity (0.06777 IU/ml/min) was displayed by the organism grown on bagasse substrate pretreated with 2M NaOH for one hour. The proximate analysis of the cellulosic residues differed from one substrate to another, with the bagasse being the best. Pulverized substrates syndicated with alkali pretreatment using 2 M NaOH for one hour was optimal for cellulase production from the cellulosic residues.

Key words: Lignocellulosic biomass, utilization, pretreatment, cellulase, substrates, Aspergillus niger AH3, fermentation, supernatant, substrate

Key words: Echis ocellatus, PLA₂, venom.