Research Article
Antibiotic Production Through Solid-State Fermentation Under a Novel Fixed-Bed Micro-Reactor
Teresa Matoso Manguangua Victor*,
Jarka Glassey,
Kristie Kamps,
Alan Claude Ward
Issue:
Volume 11, Issue 4, July 2023
Pages:
64-74
Received:
30 September 2023
Accepted:
24 October 2023
Published:
9 November 2023
Abstract: In the present study, solid state fermentation (SSF) was evaluated using a novel PolyHIPE Polymer (PHP) matrix. This matrix was developed with an approach to improve the production of antibiotics. For the production of the matrix, a batch reactor was operated with a mixing speed of 300 rpm at differents mixing times (5, 10, 15 min) as a consequence, differents pores sizes was Obtained (55, 39, 19 μm) with a sulfonated/neutralized surface chemistry. After functionalization and purification, the matrix was placed in a fixed-bed micro-reactor, designed specifically for this project; which had 16 fixed beds for the production of antibiotics in the solid state using a model filamentous bacteria Streptomyces coelicolor A3(2). The growth conditions such as the size of the pores of the matrix, were investigated in relation to the growth time (From 0 to 168 hours), and two extracts were produced, Prodigiosin a member of the family of red pigment tripyrrol and Actinorhodin a benzoisochromoquinone dimeric antibiotic that belongs to a class of aromatic polykets. The concentration of the extracted antibiotics and their activities were examined by the disc diffusion method. The two compounds produced were tested against microbial strains (Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas fluorescens, and Penicillium notatum) and the inhibition effects were measured. The results concluded that the highest specific production rate of prodigiosin (3.02 μmol ml-1h-1) and actinorhodin (26.08 μmol ml-1h-1), was achieved within the PHP matrix, with pore sizes of 39 μm and 19 μm in diameter respectively. On the other hand, the assay revealed a larger inhibition halo (diameter in mm) that was observed in the plate inoculated with DSM 10 strains (Bacillus subtilis), inhibited by Prodigiosin extract.
Abstract: In the present study, solid state fermentation (SSF) was evaluated using a novel PolyHIPE Polymer (PHP) matrix. This matrix was developed with an approach to improve the production of antibiotics. For the production of the matrix, a batch reactor was operated with a mixing speed of 300 rpm at differents mixing times (5, 10, 15 min) as a consequence...
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Research Article
The Study on Electrical and Mechanical Impact of Snail Shell Reinforced AA6061 Matrix Composites
Nduka Ekene Udoye*,
Fasola Samuel Oluwatowo
Issue:
Volume 11, Issue 4, July 2023
Pages:
75-84
Received:
1 August 2023
Accepted:
17 August 2023
Published:
17 November 2023
Abstract: There is a demand for lightweight and low-cost engineering materials with enhanced strength especially in automotive, aerospace, and structural applications in this modern age’. This study focused on developing an aluminium matrix composite using the stir casting method with snail shells of particulate size 75µm with varying proportions (4%, 8%, 12%, 16%) in order to enhance the properties of the composite such as tensile strength, hardness etc. The aluminium composites were studied and analyzed using the Brinell hardness tester for microhardness properties, UTM SM1000 for ultimate tensile strength behavior, scanning electron microscope equipped with energy dispersive spectrometer were used in studying the surface morphology and the elemental identification of the composite, X-ray diffraction was also used to categorize the crystalline phase of the composite. The results showed the XRD micrographs of the produced composite revealed the presence of calcium and hydroxyapatite derived from the snail shell on the aluminium composite. The diffractive pattern revealed a large number of reinforcements with stable intermediate phase Ca10(PO4)6(OH)2, Ca2Al3SIO4, and Ca2SIO4 and so on. The electrical properties increased in conductivity due to the presence of the snail shell particulate within the composite from 31.9693Ωm-1 to 34.6500Ωm-1, thus increasing the capacity of the composite to conduct electricity. Furthermore, the ultimate tensile strength showed a significant change of 35.8% with the maximum tensile strength of 98.89MPa, achieved at 8% wt. snail shell. The hardness increased proportionally from 55.2HRB to 63.5HRB. Based on the outcome of experiments, this research has shown the possibility of using snail shell particulates as reinforcement in aluminium metal matrix composite and will help to improve the productivity and reliability of component made of AA6061 + 8% snail shell at 75µm.
Abstract: There is a demand for lightweight and low-cost engineering materials with enhanced strength especially in automotive, aerospace, and structural applications in this modern age’. This study focused on developing an aluminium matrix composite using the stir casting method with snail shells of particulate size 75µm with varying proportions (4%, 8%, 12...
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