African Journal of Parasitology Research

African Journal of Parasitology Research ISSN 2756-3391 Vol. 11 (7), pp. 001-009, July, 2023. © International Scholars Journals

Full Length Research Paper

Possibility of the sale of a microbial medium made from industrial food waste

Zvidzai C.* ¹, Muzhinji N.¹, Chidzvondo F.¹, Mundembe R.², and Sithole-Niang I.¹

¹Biochemistry Department, University of Zimbabwe, Box MP167, Mt. Pleasant, Harare, Zimbabwe.

²Bindura University of Science and Education, P. Bag 1020, Bindura, Zimbabwe.

Accepted 21 April, 2023

Abstract

A microbial medium, designated DYSP medium, was produced from food wastes that included defatted soya, clear beer spent yeast, potato solid waste and opaque beer spent grains. Various combinations of the food wastes were used for the media formulations and evaluated for extent of supporting microbial growth of pure cultures. A 3.0 M sodium hydroxide hydrolysis followed by a neutralization process using concentrated hydrochloric acid has been established and standardized for the preparation of the medium. A dry pulverized medium was produced that could be reconstituted in distilled water (dH₂O) without settleable solids. The formulated DYSP medium supported the growth of Escherichia coli, Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Aspergillus niger and Saccharomyces cerevisiae. The composition of the medium was 35.45% protein, 5.7% nitrogen, 56.6% ash, 8.6% moisture and 0.012 mg/ml of total reducing sugar. The pH of the DYSP broth was 6.6 when reconstituted in distilled water. Traditional classical microbiological studies demonstrated that the test cultures could grow and retain normal phenotypic and morphological properties when cultured on the formulated medium.The DYSP medium containing ampicillin, isopropyl ß-D-1-thiogalactopyranoside and 5-bromo-4-chloro-3-indolyl-ß-D-galactoside proved to be an equally alternative medium in molecular biology for selection and screening E. coli TG1 cells transformed with pUC18 plasmid. Other preliminary biotechnological results showed that the formulated medium could form a base for studying and optimizing the production of penicillin by P. chrysogenum.

Key words: Food wastes, chemical hydrolysis culturing medium, fermentation and molecular biology.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 11 (6), pp. 001-014, June, 2023. © International Scholars Journals

Full Length Research Paper

Analysis of specific strains of Bifidobacterium bifidum and Lactobacillus acidophilus

Kamila Goderska* and Zbigniew Czarnecki

The August Cieszkowski Agricultural University of Poznan, Institute of Food Technology of Plant Origin, Wojska Polskiego 31, 60-624 Poznan, Poland.

Accepted 21 October, 2022

Abstract

The presented study aims to characterize Lactobacillus acidophilus DSM 20079 and DSM 20242 and Bifidobacterium bifidum DSM 20082, DSM 20215, DSM 20239 and DSM 20456 strains. Within the framework of the performed investigations, the author evaluated their biochemical properties, resistance to antibiotics, antagonism towards selected pathogens as well as the effect on their survivability of different environmental conditions with special emphasis on the conditions prevailing in the human gastrointestinal tract. The performed experiments revealed significant differences between the examined bacterial species as well as between strains of the same species. All the examined strains were characterized by diverse biochemical properties, resistance to antibiotics and showed antagonistic action against Helicobacter pylori bacteria. The tested strains of the L. acidophilus bacteria were found to exhibit antagonistic activity against Escherichia coli and Salmonella enteritidis bacteria, although the observed activity was smaller in comparison with the antagonistic activity against H. pylori. These data confirm reports about the antagonistic effect of probiotic bacteria on the growth of pathogenic bacteria. All the examined bacterial strains fulfil the basic criterion expected from probiotic strains, that is, are capable of surviving in the ‘in vitro’ conditions of the gastrointestinal tract, at low pH and in the presence of bile salts.

Key words: Bifidobacterium bifidum, Lactobacillus acidophilus, probiotic, antibiotic resistance, acidity resistance, bile tolerance, antagonistic activity.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 11 (6), pp. 001-004, June, 2l023. © International Scholars Journals

African Journal of Parasitology Research ISSN 2756-3391 Vol. 11 (5), pp. 001-005, May, 2023. © International Scholars Journals

Key words: Hepatocellular carcinoma, Hepatitis B virus.

African Journal of Parasitology Research ISSN 2756-3391 Vol. 11 (5), pp. 001-004, May, 2l023. © International Scholars Journals

Full Length Research Paper

Trichosporon cutaneum resistance to hazardous substances as measured by dielectric

Filadia P. Tileva¹, Lyubov K. Yotova¹ and Gerard H. Markx²*

¹Department of Biotechnology, University of Chemical Technology and Metallurgy, BU-1756 Sofia, Bulgaria.

²School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS, UK.

Accepted 28 November, 2022

Abstract

Conditioning of cultures involves growing cells in the presence of increasing amounts of a toxic chemical. In order to investigate how conditioning affects a culture’s ability to resist new challenges, the resistance of Trichosporon cutaneum to various toxic chemicals, before and after conditioning to growth on phenol, was investigated by measuring the capacitance of cell suspensions at 0.4 MHz following a toxic challenge. The results show that cells grown on phenol are more resistant to the influence of polar aromatic toxic chemicals such as phenol (log P_ow = 1.48) and benzylalcohol (log P_ow = 1.1), but less resistant against less polar non-aromatic compounds such as n-octanol (log P_ow = 2.9). In reverse, cells grown on glucose were found to be more resistant against n-octanol, but less so against phenol and benzylalcohol. The results indicate that cells, adapted to be more resistant to one type of substance, may become more susceptible to other compounds.

Key words: conditioning, adaptation, membrane, Trichosporon cutaneum, capacitance.