Frontiers of Agriculture and Food Technology

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-005, January, 2020. © International Scholars Journals

Full Length Research Paper

Enzyme activity of a Phanerochaete chrysosporium cellobiohydrolase (CBHI.1) expressed as a heterologous protein from Escherichia coli

Howard R.L.¹*, Masoko P.¹ and Abotsi E.²

¹Microbiology, School of Molecular and Life Sciences, University of the North, P/Bag X1106, Sovenga, 0727, South Africa

²Biochemistry, School of Molecular and Life Sciences, University of the North, P/Bag X1106, Sovenga, 0727, South Africa.

Accepted 11 October, 2019

Abstract

The aim of this study was to produce a secreted, heterologously expressed Phanerochaete chrysosporium cellobiohydrolase (CBHI.1) protein that required no in vitro chemical refolding and to investigate the cellulolytic activity of the clone expressing the glutathione S- transferase (GST) fused CBHI.1 protein. Plate enzyme activity screening of E. coli cells transformed with pGEXcbhI.1 vector on carboxy-methyl-cellulose (CMC) produced several clones which produced clearing zones on CMC when induced. A randomly selected representative pGEXcbhI.1 clone produced hydrolysis on both Avicel and CMC when induced. Crude protein extracts obtained from the induced pGEXcbhI.1 clone exhibited time dependent enzymatic activity against both CMC and Avicel.

Key words: Phanerochaete chrysosporium, cellobiohydrolase, cellulase activity, heterologous expression.

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-008, January, 2020. © International Scholars Journals

Full Length Research Paper

Heavy metals concentrations and burden in the bivalves (Anadara (Senilia) senilis, Crassostrea tulipa and Perna perna) from lagoons in Ghana: Model to describe mechanism of accumulation/excretion

Fred A. Otchere

Azimuth Consulting Group, 218 – 2902 West Broadway, Vancouver, British Columbia.V6K 2G8 Canada, E-mail: [email protected]; phone: 1.604.608.4283.

Accepted 09 November, 2019

Abstract

Seasonal sampling of the bivalves: Anadara (Senilia) senilis (n = 260), Crassostrea tulipa (n = 220), from two ‘open’ lagoons (Benya and Ningo) and a ‘closed’ lagoon (Sakumo), and Perna perna (n = 170), from rocky shores adjacent to Benya and Sakumo, were analyzed for their total Cu, Zn, Fe, Mn, Cd and Hg concentrations and total body burden (that is concentration multiply by total flesh weight) . Median concentrations for cockles were: 5, 38, 710, 10, 0.22 and 0.20 µg/g dw respectively. Cd and Hg levels in dry season samples were higher than those in wet season. While Zn and Fe dry season levels were lower than wet season with no variation in Cu and Mn. Median total body burden in cockles were: 3.3, 30.5, 370, 5.2, 0.28 and 0.13 µg respectively. Geographical variations observed were mostly due to size distribution rather than the ecological differences between stations. Log-transformed regression relationships between body burden and size were used to compare the species. Relationship between condition index, body burden and concentration were used to develop a model to describe mechanism of accumulation/excretion.

Key words: Heavy metals, bivalves, marine, lagoons, seasonal variation, accumulation, Ghana.

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-005, January, 2020. © International Scholars Journals

Full Length Research Paper

Petroleum degrading potentials of single and mixed microbial cultures isolated from rivers and refinery effluent in Nigeria

P.O. Okerentugba and O.U. Ezeronye

Department of Microbiology University of Port Harcourt Choba, Port Harcourt, Nigeria.

Accepted 19 October, 2019

Abstract

The ability of three bacterial isolates (Bacillus spp, Micrococcus spp and Proteus spp.) and some fungal species (Penicillin spp., Aspergillus spp. and Rhizopus spp.) isolated from two rivers and refinery effluent to degrade two Nigerian Crude oils was studied. The results showed changes in pH, optical density and total viable count for the bacterial isolates after a 17-day period. There was an increase in biomass for the fungal isolates after a 35-day period. It was observed that these organisms were able to utilize and degrade the crude oil constituents, with bacterial isolates showing increase in cell number and optical density as pH decreases. Single cultures were observed to be better crude oil degraders than the mixed cultures (bacteria or fungi). It was also observed that oil degraders could be isolated from a non-oil polluted environment, although those from oil-polluted environments have higher degradation potentials.

Key words: Petroleum, refinery, biodegradation, plasmids, effluent.

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-004, January, 2020. © International Scholars Journals

Full Length Research Paper

Effects of sulphuric acid and hot water treatments on seed germination of tamarind (Tamarindus indica L)

S. Muhammad^1* and  N. A. Amusa²

¹Department of Biological Sciences, Usmanu Danfodiyo University, Sokoto, Nigeria.

²Institute of Agricultural Research and Training, Obafemi Awolowo University, P.M.B. 5029, Moor Plantation, Ibadan. Nigeria.

Accepted 11 August 2019

Abstract

A study was carried out to investigate the effects of sulphuric acid and hot water treatments on the germination of Tamarind ( Tamarindus indica L). Seeds were placed on moistened filter papers in 28 cm diameter Petri dishes under laboratory condition for germination. 330 seeds of T. indica (10 seeds per Petri dish) with three replicates each were used. The highest germination was recorded in seeds treated with 50 per cent sulphuric acid concentration with 60 min soaking period. Germination was observed to be enhanced by increase in the sulphuric acid concentration, water temperature, and soaking period in all the trials, except with absolute sulphuric acid where poor response was observed. Results of this study may serve as useful information in the production and improvement of the tree species, as knowledge on seed germination requirements is a critical factor in seedlings production.

Key words: Tamarind, Tamarindus indica, sulphuric acid, hot water, germination.

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-005, January, 2020. © International Scholars Journals

Full Length Research Paper

Phylogenetic and molecular evolutionary analyses of gypsy group retrotransposon families in the Egyptian cotton Gossypium barbadense

Abdel Ghany A. Abdel Ghany¹ and Essam A. Zaki^2*

¹Institute of Efficient Productivity, Zagazig University, El Zagazig, Egypt.

²Genetic Engineering & Biotechnology Research Institute, GEBRI, Research Area, Borg El Arab, Post Code 21934, Alexandria, Egypt.

Accepted 11 September, 2019

Abstract

Gypsy group retrotransposons in the Egyptian cotton, Gossypium barbadense, was examined by phylogenetic and molecular evolutionary analyses. DNA sequences of gypsy group retrotransposons in two G. barbadense cultivars revealed that these sequences are heterogeneous and represent two distinct families. Sequence variation between these families seems to preserve coding information of the reverse transcriptase domain. The high ratio of synonymous to nonsynonymous changes indicates that the reverse transcriptase domain of these families is evolving under purifying selection. Our phylogenetic analysis revealed that the closest relatives of cotton retroelements are found in other plants gypsy group retrotransposons. Cotton retroelements-encoded transcripts were detected in their related respective young seedlings using RNA slot-blot hybridization, suggesting their transcriptional activity. The wide distribution of gypsy group retrotransposons and the detection of their encoded transcripts illustrate their active role in the Gossypium genome.

Key words: Evolution, Gossypium, gypsy, retrotransposons, reverse transcriptase, substitution rates, transcription.

Frontiers of Agriculture and Food Technology ISSN 7295-2849 Vol. 10 (1), pp. 001-007, January, 2020. © International Scholars Journals

Full Length Research Paper

Mevastatin-induced inhibition of cell growth in avocado suspension cultures and reversal by isoprenoid compounds

Dudley I. Mitchell and A. Keith Cowan*

Research Centre for Plant Growth and Development, School of Agricultural Sciences and Agribusiness, University of Natal-Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa.

Accepted 11 August 2019

Abstract

Cell suspension cultures were established using soft, friable callus derived from nucellar tissue of ‘Hass’ avocado (Persea americana Mill.) seed from fruit harvested 190 days after full bloom. Cell cultures were maintained in liquid medium supplemented with naphthalene acetic acid (NAA), isopentenyl adenine (iP) and sucrose and sub-cultured at 14 day intervals. Growth was typically sigmoidal with a lag phase of 7 days followed by an exponential phase of approximately 14 days. Mevastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR, EC 1.1.1.34) was used to probe the contribution of metabolites of the isoprenoid pathway for avocado cell growth. Treatment with mevastatin inhibited cell growth and caused loss of cell viability. Inhibition of cell growth was transient and at all concentrations of mevastatin tested, recovery was evident within 17 days. The arrest of cell growth by 1 and 40 µmol/L mevastatin was negated when this inhibitor of HMGR was supplied in the presence of either mevalonolactone (MVL) or farnesyl diphosphate (FDP) . By comparison, co-treatment of cells supplied 1 µmol/L mevastatin with stigmasterol showed little or no response whereas at 40 µmol/L mevastatin, stigmasterol induced partial recovery of cell growth. The results indicate a requirement for mevalonic acid (MVA) and cytosolic isoprenoid biosynthesis, in particular FDP, for avocado cell growth and support the hypothesis that appearance of the small-fruit phenotype in ‘Hass’ is inextricably linked to activity of HMGR.

Key words: Avocado, cell suspensions, farnesyl diphosphate, HMGR, mevalonic acid, Persea americana.