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Production of Bioethanol from Palm Oil Mill Effluent using Starter Cultures
(New York Science Journal, 2013-01-01) Wakil, Fasiku, Samuel Adedayo Sherifah Monilola; Adelabu, Onilude, Anthony Abiodun Adebola Blessing
Palm Oil Mill Effluent (POME) has great potential as a substrate for acetone, butanol and ethanol fermentation because it contains a mixture of carbohydrates including starch, hemicellulose, sucrose and other carbohydrates that can be utilized by microorganisms. Hence microorganisms were isolated from spontaneously fermenting POME, the predominant strains were selected as starters and the effect of starters singly and in combination for bioethanol production was evaluated/determined. POME was spontaneously fermented for 21 days from which samples were taken every 3 days for analyses of pH, microbial quality, ethanol content, free fatty acid and lipase activity. Microorganisms isolated were characterized and identified. Moulds isolated were strains of Aspergillus and Penicillum genera, yeast were Yarrowia lipolytica, Saccharomyces cerevisiae and Candida spp., while bacteria were strains of Bacillus spp. and Micrococus sp. Sterile palm oil mill effluent was fermented with the starter cultures for 12 days and analyzed every 3 days for bioethanol production. Saccharomyces cerevisiae, while used singly, produced the highest bioethanol (3.70%) concentration. Statistical analysis shows that bioethanol and percentage free fatty acid production by single and combined starter fermented POME is significantly different (P ≤0.05) while lipase production was not significantly different (P≥0.05). The study reveals that fermentation of POME for 12days at room temperature (30+20C) using Saccharomyces cerevisiae singly gives the highest bioethanol concentration. Therefore, the use of starter cultures for fermentation of POME for the production of bioethanol is a potential solution for the control of pollution generated from the annual disposal of POME.
Production of Bioethanol from Spontaneous Fermentation of Palm Oil Mill Effluent (POME).
(Science Publications, 2013-01-01) Wakil, Fasiku, Samuel Adedayo Sherifah Monilola; Adelabu, Onilude, Anthony Abiodun Adebola Blessing
The feasibility of bioethanol production from spontaneous fermentation of palm oil mill effluent was carried out. Cooled POME (1.5L) was allowed to ferment spontaneously for 21 days for analysis of microbial quality, free fatty acid, lipase activity and ethanol contents. Effect of pH and supplementation on ethanol and other parameters were also determined every 3 days for 21 days. Ethanol content increased as the concentration of glucose increased and highest ethanol content (0.9%) was recorded at 25g/L and 30g/L of glucose in POME. Sugar cane bagasse supplementation had highest ethanol content (0.9%) at 20g/L and 30g/L thereafter decreased as its supplementation increased. Corn steep liquor supplementation did not have any effect on ethanol production from POME. Fermented POME supplemented with corn steep liquor had the highest lipase activity (0.00756μg/ml/day) and free fatty acid (2.561%) at 150ml/L. POME supplemented with 30g/L glucose and 30g/L sugar cane bagasse had the highest record of ethanol content (2.3%) at pH of 8.5 with highest free fatty acid (5.029%) at pH 6.5 on the 12th day of fermentation and highest lipase activity (0.03200μg/ml/day) was recorded at pH 6.5 on the 3rd day of fermentation. A relative high bioethanol can be produced by spontaneously fermenting POME with addition of 30g/L of glucose and 30g/L of sugar cane bagasse for 12 days at pH of 8.5.
Isolation and identification of antimicrobial-producing lactic acid bacteria from fermented cucumber
(African Journal of Biotechnology, 2014-01-01) Wakil, Laba, S. A. S. M.; and Fasiku, S. A
Lactic acid bacteria (LAB) responsible for spontaneous fermentation of cucumber were isolated and their antimicrobial producing potentials were screened against 10 indicator strains. 65% of the isolated LAB produced antimicrobial activities against at least two indicator strains. The indicator strains used were: Escherichia coli, Bacillus licheniformis, B. cereus, Proteus species, Staphylococcus aureus, Salmonella species, Pseudomonas flourescence, P. aeruginosa, Serratia species and Pediococcus acidilactici. Of the 42 antimicrobial producing isolates characterized, 16, 12, 6 and 8 were identified as Lactobacillus plantarum, L. fermentum, L. acidophilus and Leuconostoc mesenteroides, respectively. Highest lactic acid producers DW7, DT6, DH13 and DF12 were selected for further investigations and were identified as L. plantarum. None of the selected L. plantarum isolates had antagonistic activity against S. aureus, Salmolnella species and P. acidilactici. The effect of pH and temperature on the antimicrobial activity of selected isolates showed that pH 5.5 and temperature 30°C were the optimum pH and temperature respectively. Thus, the selected L. plantarum isolates are good producers of antimicrobial compounds and could be suitable for application in food industry in preservation of vegetables so as to increase their shelf life.
Production of bacterial amylases and cellulases using sweet potato (Ipomoea batatas. (L.) Lam.) peels
(African Journal of Biochemistry Research, 2015-01-01) Olanbiwoninu, Fasiku, Samuel Afolake Atinuke
Peels of sweet potato (Ipomoea batatas) were buried in the soil for 14 days and the isolates associated with the degradation of the peels were obtained using standard microbiological procedures. The bacterial isolates obtained were screened for amylolytic and cellulolytic activities under different pH and temperatures as parameters and optimized for enzyme production. Sixteen (16) bacterial isolates were obtained and characterized and screened for amylase and cellulase production. Bacillus pumilus has the highest frequency of occurrence (18.75%) followed by B. subtilis (12.50%). After 24 to 48 h of incubation, B. pumilus produced highest concentration of amylase at 55°C, pH 6 (5.4 U/mL) while B.subtilis had the best cellulase production of 0.75 U/mL at 55°C, pH 7. B. pumilus and Bacillus subtilis produced the highest amylase and cellulase concentrations and seem to be the potential sources of these enzymes for industrial application.
Isolation and identification of thermophilic cellulolytic yeast from cassava waste dump
(Journal of Science Research,, 2015-01-01) Onilude, Adekoya, A.O A.A.; Wakil, Fasiku, S. A S. M; Ja’afaru, I. M
Cellulase is an enzyme complex which breaks down cellulose to glucose. The need for economical, complete and fast industrial processes necessitates the use of very active starters able to operate at high temperature of production to degrade cheap nutrients most of which are cellulolytic; hence the search for thermophilic cellulolytic yeasts from the environment. Isolation and identification of thermophilic yeasts were made from the soil samples using standard procedures and obtained isolates were screened for cellulolytic enzymes production. The enzymes were characterised using different parameters such as temperature, pH, substrate concentrations, enzyme concentrations and metal ion concentrations. A total of seven thermophilic yeasts were isolated from cassava waste dump sites and identified as Torulopis sphaerica, Kloeckera apiculata, Pichia canadensis, Pichia species, Candida krusei, Candida utilis and Rodotorula rubra. They all had optimum growth at temperature and pH of 55ºC and 6.0 respectively. The optimum temperature and pH for cellulolytic activities ranged from 45-55ºC and 5-6 respectively. Cellulolytic activities increased with increase in the concentration of substrate, enzymes and metal ions.
Occurrence and Environmental Implications of Calcareous Nannofossils in Surface Sediments of the Western Gulf of Guinea: off Lagos Coast, South-western Nigeria
(Journal of Environment and Earth Science, 2016-01-01) ADAMOLEKUN, Olajide J.; UMOH, Ekaete E.
The application of calcareous nannofossils in oil exploration, and environmental studies is playing an increasingly important role all over the world. Most recent researches on this subject area in Nigeria are confined/restricted to the oil producing Niger Delta leaving most other areas untouched. This however limits nannofossils’ application in biostratigraphic and paleoenvironmental interpretation of non oil producing areas within the country. Before now, nannofossils occurrence and application have not been documented in the surface sediments of Nigeria. Consequently, calcareous nannofossils have been investigated in thirteen (13) surface sediments samples of the littoral area from the continental shelf of western Gulf of Guinea, off Lagos coast. Primarily, this research was aimed at determining the occurrence (and or non occurrence), and relative abundance of nannofossils in surface sediments of the area with which the age of the sediments, paleoenvironment and paleoecological condition(s) could be determined.The samples were collected with the aid of grab sampler, allowed to dry and subjected to detailed lithologic description. Furthermore, the samples were subjected to nannofossils analysis by standard method of preparation. Both qualitative and quantitative analysis was done using the high power Olympus Transmitted Light Microscope (TLM). The occurrence of nannofossils has been established in the study area (littoral area of the western Gulf of Guinea). Most of the sediments are poorly consolidated, fine to coarse grained sand with little amount of clay ant silt fractions that yielded Pliocene to Recent nannofossils (mainly Pleistocene). A total population of 1132 belonging to five different genera (Calcidiscus, Ceratolithus, Gephyrocapsa, Helicosphera and Reticulofenestra) and seven species were found in the studied samples with Gephyrocapsa caribbeanica being the most abundant (followed by Gephyrocapsa oceanica of a little lower abundance). The species indicate a truly shallow marine environment within recent sediment accumulation.
Calcareous Nannoplankton Analysis of Well BL-2, Deepwater Offshore, Niger Delta Basin
(Journal of Mining and Geology, 2019-01-01) Umoh, Oyafunke, O.A E.E.; Ighodaro, E.J
Sequence Stratigraphy and biostratigraphy are recent tools that are being developed and incorporated together for the understanding of stratigraphic distribution and prediction of source, reservoir and seal rocks. These tools were used to analyze well BL-2, within the depth intervals of 6000ft - 8880ft offshore, Niger Delta. Calcareous Nannoplankton assemblages encountered in the study were used in determining the biozone and age of the samples of the penetrated well. Intercalation of sand and shale lithologies obtained from the well logs suggests the well BL-2 penetrated the Agbada Formation. Three nannozones were determined - NN10, NN11 and NN12, two sequence boundaries and three maximum flooding surfaces with ages and 5.0Ma, 5.8Ma, 7.0Ma respectively were delineated and used to divide the stratigraphic succession into depositional sequences and their corresponding system tracts. Highstand and Transgressive system tracts were identified in each of the three depositional sequences. However the absence of lowstand system tract can be inferred to have resulted from erosion by succeeding transgressive system tracts. The alternation of highstand and transgressive system tracts is inferred to provide the desired combination of reservoir and source rock required for hydrocarbon generation. The unit's age is Late Miocene to Early Pliocene.
Biostratigraphy and Paleoenvironmental Studies of Onigbedu Sediments, Ewekoro Local Government, Ogun State.
(IRE Journals, 2019-12-01) UMOH EKAETE ENAMEKERE, OLANIYAN OLAMIDE RILWAN
Abstract- Eleven (11) outcrops samples in vertical succession at the blast surface of the purechem cement mine, Onigbedu, Ewekoro from the Akinbo and Ewekoro Formationsat an interval of one meter depth were reconnoiter in order to establish the lithofacies, age and paleoenvironment. The biostratigraphic results indicated that the study area was deficient of calcareous nannofossils as well as planktonic foraminifera but benthic foraminifera were moderate to abundant in sample S2 of the Akinbo formation and samples L2, L3, L4, L5, L6, and L7 of the Ewekoro formation. Microfacies analysis carried out on three selected samples of the Ewekoro formation harmonized with already existing lithofacies classification of the Ewekoro formation as Sample L2 and Sample L4 -Biomicite, Sample L6- Biosparite. The presence of foraminifera species consisting of rare calcareous benthic, absence of Planktics and Calcareous nannofossils indicate deposition in a shallow water. Foraminiferal assemblage is characterized by Valvulineria sp, Quinqueloculina sp, Hanzawaia concentrica, Calcareous indeterminate and Ostracod suggesting sediments deposition in a marginal marine setting (Coastal Deltaic). The results of the analyses also indicate that these outcrop samples were deposited during the late Paleocene epoch, estimated numerical age of 56.8Ma to 57.3Ma and straddling the Valvulineria martinezensis Niger Delta Benthic Foraminiferal zone.
Nanno-Bioevents and Condensed Section of Well –BXW Offshore, Niger Delta, Nigeria
(International Journal of Scientific Engineering and Science, 2020-01-01) UMOH, Ekaete Enamekere
Ditch cutting samples from well - BXW in the offshore area of the Niger Delta were studied for their lithofacies and nannofossil content with the aim of establishing age and stratigraphic significance of the condensed section delineated from the well. Standard procedures were employed for lithologic description and nannofossils preparation techniques. The lithofacies penetrated thick shale units and some sandy shales. The rich and well preserved calcareous nannofossils recovered allowed the establishment of four zones of NN12, NN11, NN9 and ?NN8 belonging to early Pliocene - Late Miocene (Zanclean - Tortonian stage). The condensed sections identified were tied to 5.0Ma, 5.8Ma, 7.4Ma and 9.5Ma maximum flooding surfaces. Detailed analyses of condensed sections as important framework for assessing: age; acme /characteristic assemblages of nannofossils within the condensed section; paleo-depositonal environment; potential source rock; information on rate of sedimentation, and a glimpse of the oceanographic condition in the studied basin was presented.
CHEMOSTRATIGRAPHIC ANALYSIS OF ASN-1 WELL, UGHELLI DEPOBELT, NIGER DELTA
(Global Scientific Journals, 2020-03-01) Umoh, Ekaete Enamekere; Ebahor, Abraham Isreal
Chemostratigraphy is a valuable tool in the correlation of sedimentary successions based on sensitive changes in concentration of key major, minor and trace elements. Fifteen ditch cutting samples collected within the depth range of 5660ft - 8550ft from well ASN-1, Greater Ughelli depobelt, Niger Delta were analysed for their litho logic and elemental concentration with the aim to investigate depositional environment, source area composition, provenance and the weathering index of the samples. The lithologic descriptions were interpreted from gamma ray well logs and petrographically and their elemental values were analysed using AAS Spectrophotometer. The Lithosection indicates shale and sand units’ indexes inferring maturity and area of deposition, the depositional environment is a transitional zone (fluvial deltaic terrain). The weathering indexes CIA, CIW and PIA values ranges from 1.06 to 41.8, on average indicates low to moderate weathering in the source area with weathering of some sand fraction. Various calculated values of the weathering indices: Chemical Index of Alteration (CIA), Plagioclase Index of Alteration (PIA), Chemical Index of Weathering (CIW) and scatter plots of formulated ratios of Al/Na vs chemical index of alteration (CIA) were plotted to determine the weathering indexes. This also inferred their recycling processes are insignificant. The clay content is low and feldspars are averagely high implying immaturity.
FORAMINIFERAL ANALYSIS AND PALEOENVIRONMENTS OF SEDIMENTS IN WELL -AA, DEEPWATER OFFSHORE, NIGER DELTA, NIGERIA.
(GLOBAL JOURNAL OF PURE AND APPLIED SCIENCES, 2020-03-27) UMOH, EKAETE ENAMEKERE; FASINA, PEACE OLUWASEYI
Foraminiferal analysis was carried out on twenty five (25) ditch cutting samples from well -AA, offsore Niger Delta covering a depth interval of 9000ft-11025f. The study was aimed at age deduction, zoning the well, and interpreting the paleoenvironment of deposition. Lithostratigraphic description carried out on the sample revealed that the bulk lithofacies constitute shale with streaks of sand (fine-medium) between 9170ft - 9210ft and 9360ft -9380ft. The entire analysed interval was barren of planktonic foraminifera while depth 9960ft revealed a spot occurrence of Lagena spp, representing the only calcareous benthic foraminifera recovered in the entire interval. Few to common occurrences of deepwater agglutinated foraminifera were found in the well, dominated by some species of Haplophragmoides spp and Haplophragmoides narivaensis. Other foraminifera with rare and scattered occurrence includes, Cribrostomides spp, Bathysiphon spp, Troahammina spp, Cyclammina spp, Cyclammina cancellata, Valvulina spp, and Glomospira spp. The only microfaunal associated accessory recovered is ostracod at depth 1080ft. The analysed intervals was assigned a Middle – Late Miocene (N17 and older age) based on the FDO of Haplophragmoides narivaensis. The environment of deposition is based on the distribution of typical deep water arenaeceous foraminifera species recovered in the study. The predominance of the arenaeceous forms over calcareous forms suggest outer shelf environment of deposition.
An Integrated Studies: Bio facies Analysis of Sediments of Well B -1, Offshore, Niger Delta
(IRE Journals, 2020-04-01) UMOH, EKAETE ENAMEKERE
Abstract- Biofacies analysis of twenty five samples from well B-1, offshore Niger Delta, based on the nannofossil and foraminiferal content were carried out. The aim was to identify the biozones, determine the age and reconstruct paleoenvironment of the sediments. From the diagnostic taxa recovered two biozones were recognized for the nannofossil NN7 (Discoater Kugeri zone) and NN6 Cyclicargolithus Floridanus zone), while the foraminferal zone identified include N13-N12 and N11, both Calcareous nannofossil and Foraminiferal analysis indicate middle Miocene. A proximal to distal inner neritic (6440 – 6860ft), middle – outer neritic (6860 - 7640ft), shallow inner neritic (7760 – 9140ft) and middle – outer neritic (9290 – 10340ft) paleoenvironment was recognized for the study intervals. Paleoenvironmental deductions were based primarily on benthic foraminiferal assemblage and abundance and diversity of species. Presence or absence of planktic foraminifera and calcareous nannofossils also helped in deciphering Open Ocean
Use of Sedimentological and Geochemical Parameters to Evaluate the Lithologies and Geochemical (Na/Zn and K/Mn) Ratios of OGE-1 Well, Niger Delta Basin
(J. Appl. Sci. Environ. Manage, 2020-06-01) IGHODARO, OKIOTOR, M.E E.J; UMOH, ITIOWE, K EE
This work focuses on subjecting ninety (90) sidewall core well samples to sedimentological and geochemical parameters to determine the lithologies and the geochemical ratios of the OGE-1 Well in the Niger Delta Basin. The sedimentological analysis with sample description yielded lithologies that are sand, shaly sand, sandy shale and shale. The sand lithologies ranged from fine to coarse grained, well sorted to poor sorted at different depths, while the shale lithologies ranged from light to dark coloured shales which is controlled by the organic matter content in the shale. This finally produced a lithologic frame work of the well. The result of the geochemical analysis led to the creation of the geochemical ratio of Na/Zn (0.739 – 5.610) and K/Mn (21.170 – 69.37) for 90 side wall core samples. Na and K had variations in their graphs showing intermittent alternating abundance downhole. Na and K being components of the weathering of feldspars are indicative of abundance of clay minerals. The variation of the Na/Zn and K/Mn profile indicates the alternate deposition of clay and sand size deposits giving the environment of deposition to be paralic.
Mathematical Modelling of the Addiction of Drug Substances among Students in Tertiary Institutions in Nigeria
(Journal of Biomedical Research, 2021-09) Binuyo, Adeyemi Olukayode
In this paper, we formulated a mathematical model for the addiction of drug substances among students in the tertiary institutions in Nigeria. The model explains the dynamics of the use and the addiction of certain substances that are perceived as mood changing by the students in the tertiary institutions in Nigeria. The drug model will be analysed qualitatively. The basic reproductive number which is the drug addiction number of the mathematical model was determined using the next generation procedure. It was found that the drug free equilibrium point was found to be locally asymptotically stable whenever the drug addiction number is less than one and unstable otherwise. The analysis revealed that an increase in the recruitment rate of students and the rate at which the students return to the use and addiction of drugs would cause an increase in the drug addiction number. There are impacts on interaction among non-drug users and drug users in the system with time. An increase in the contact or limitation rate increases the population of drug users. It is hereby recommended that; government should intensify efforts to reduce or stop the spread of selling and purchasing of the drug substances through government policies among the students in the tertiary institutions in Nigeria.
Development of an Improved Convolutional Neural Network for an Automated Face-Based University Attendance System
(Paradigm Plus, 2023-04-27) Ojo, Olufemi S.; Oyediran, Mayowa O.
Because of the flaws of the present university attendance system, which has always been time intensive, not accurate, and a hard process to follow. It, therefore, becomes imperative to eradicate or minimize the deficiencies identified in the archaic method. The identification of human face systems has evolved into a significant element in autonomous attendance-taking systems due to their ease of adoption and dependable and polite engagement. Face recognition technology has drastically altered the field of Convolution Neural Networks (CNN) however it has challenges of high computing costs for analyzing information and determining the best specifications (design) for each problem. Thus, this study aims to enhance CNN’s performance using Genetic Algorithm (GA) for an automated face-based University attendance system. The improved face recognition accuracy with CNN-GA got 96.49% while the face recognition accuracy with CNN got 92.54%.
Applications of Microbial Enzymes in Industries
(Journal of Multidisciplinary Sciences: MIKAILALSYS, 2026-01-28) Fasiku, Samuel Adedayo; Afolabi, Femi Johnson; Egbeleke, Tawakalit Adeola; Fashogbon, Racheal Oluwayemisi
Microbial enzymes, produced by microorganisms such as bacteria, fungi, and algae, have emerged as indispensable biocatalysts across multiple industrial sectors due to their efficiency, versatility, and activity under diverse environmental conditions. This review aims to highlight the major industrial applications of microbial enzymes and synthesize evidence on their functional roles in contemporary bioprocesses. More than 80 published articles, textbooks, and newsletters were retrieved from reputable platforms, of which approximately 50 were selected for detailed analysis based on relevance and quality. The reviewed literature shows that enzymes now play critical roles in everyday life, with broad applications in medicine, pharmacy, environmental remediation, food processing, detergent manufacture, and energy production. In the detergent industry, amylases, lipases, and proteases are used to break down starch, fats, oils, and proteins, thereby enhancing washing efficiency. In the food sector, microbial enzymes support milk hydrolysis in cheese production, contributing to characteristic flavour development, and are widely employed in fruit juice clarification. In the energy sector, cellulases, xylanases, and lignin-degrading enzymes enable the breakdown of lignocellulosic substrates to release reducing sugars for biofuel production. Medically, L-asparaginase has been used in the treatment of leukaemia, while laccases are applied in the degradation of dyes and the reduction of chemical waste in environmental applications. The diversity of microbial sources allows these enzymes to function under extreme conditions, expanding their usability across varied industrial environments. Overall, the review concludes that microbial enzymes have extensive and growing industrial relevance, underscoring the need for continued research and development to optimize their production, stability, and application in sustainable biotechnological processes.
PRODUCTION AND CHARACTERISATION OF L-ASPARAGINASE FROM Priestia megaterium GAFA
(2026-02-20) Fasiku Samuel Adedayo; Oladunni Atilade Amos; Okpala Gift Chimamaka; Fasiku Taiwo Bukola; Afolabi Femi Johnson
L-asparaginase is an enzyme used to treat acute lymphoblastic leukaemia due to its ability to break downexternal L-asparagine necessary for the growth of cancer cells. This work investigated the optimisation of Lasparaginase production and the effect of various factors on the activities of the produced enzyme. An Lasparaginase-producing bacterium collected from the Department of Microbiology and Biotechnology Laboratory was identified using 16S rRNA. The production of L-asparaginase was optimised using Response Surface Methodology (RSM), and the experimental design was validated. The effect of environmental factors on L-asparaginase was determined. The L-asparagine-producing bacterium was identified as Priestia megaterium GAFA with an accession number PP390497. Optimal production (10594.1 U/mL) was validated using glucose as a carbon source, L-asparaginase only as a nitrogen source, fermented at pH 7.76 for 73 hours with an inoculum load of 7.7%. The Ca²⁺ ion significantly increased L-asparaginase activity by 76% compared with the control at p<0.05. The enzyme was active over a wide pH range (4–8), with maximum activity at pH 6.0. The highest activity was observed at 60 °C after 1 hour of incubation. The production of L-asparaginase by Priestia megaterium GAFA was optimised, and environmental factors influenced its activity.
Production of laccase by Pleurotus ostreatus through submerged fermentation and its decolourisation potential
(Bulletins of Natural and Applied Sciences, 2026-02-20) Fasiku, Samuel Adedayo; Abimbola, Muinat Titilope; Afolabi, Femi Johnson
Laccases are multicopper oxidase enzymes with significant industrial and environmental applications, including bioremediation and the degradation of textile dyes. This study investigated laccase production by Pleurotus ostreatus using submerged fermentation and assessed its decolourisation potential. Lignocellulosic wastes, including sugarcane bagasse, rice straw, maize cob, conifer litters, and maize straw, were evaluated as substrates for laccase production. Parameters such as carbon and nitrogen sources, pH, inoculum size, and incubation period were optimised. Enzyme activity was quantified using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as a substrate, characterised with respect to metal ions, pH, temperature, and time, and decolourisation ability was determined using various dyes. The highest laccase yield (435.04 µU/L) was recorded in a medium containing 1% of maize straw, supplemented with 1% glucose as the carbon source and 0.1% peptone as the nitrogen source, at an initial pH of 7.0, inoculated with four circular 7 mm Pleurotus ostreatus plugs, and incubated for 6 days. Metal ions affected laccase activity. Activity was stable across a wide pH range (3.6–9.5), with the highest activity recorded at pH 8.0. Laccase activity was also stable across temperatures (25–60℃) and time periods (10–60 minutes). Pleurotus ostreatus laccase decolourised malachite green and Leishman blue by 21.8% and 21.4%, respectively. Laccase production by Pleurotus ostreatus was optimised through submerged fermentation, promoting the utilisation of agro-wastes and offering a scalable method for industrial enzyme production. Dyes were decolourised by laccase, demonstrating the enzyme’s potential and its application in the textile industry.
Applications of Microbial Proteases: A Review
(Journal of Multidisciplinary Sciences: MIKAILALSYS, 2026-03-08) Fasiku, Samuel Adedayo; Afolabi, Femi Johnson; Odeyale, Christiana Ify
Microbial proteases have attracted increasing attention as eco-friendly biocatalysts because of their broad functional versatility and advantages over proteases derived from plants and animals. This review examines the major sources, classification, production methods, and sectoral applications of microbial proteases. Produced by bacteria, actinomycetes, and fungi, microbial proteases are classified according to optimum pH range, catalytic mechanism, and site of action, and are commonly generated through submerged and solid-state fermentation. The review shows that these enzymes have diverse industrial applications in detergent, leather and tanning, food and dairy, brewing and beverage processing, and textile production. In medical and pharmaceutical contexts, microbial proteases are applied in wound debridement and healing, antimicrobial and antibiofilm activities, drug development, diagnostics, and therapeutic interventions. In agriculture, they support animal feed supplementation by improving protein digestion and function as biological control agents by disrupting pathogen attachment, penetration, and colonization of plant tissues. In the environmental sector, their applications include waste management, bioremediation, and the recycling of keratinous and other protein-rich wastes. Overall, this review underscores the wide-ranging utility of microbial proteases across industrial, medical, agricultural, and environmental sectors, highlighting their potential as sustainable biological agents for diverse biotechnological applications.
Characterization of silver nanoparticles synthesized from Helianthus annuus leaf extracts and antibacterial potential against foodborne pathogens
(Discover Chemistry, 2026-03-11) Fashogbon, Racheal Oluwayemisi; Adejoh, Olubunmi P.; Fasiku, Samuel Adedayo; James, Stephanie N.; Ajayi, Olutosin O; Adeyemi, Abiodun A.
The synthesis of nanoparticles using biological substances, such as plants, has proven to be more beneficial, eco-friendly, and cost-effective. This study emphasised the green biogenic synthesis of silver nanoparticles (AgNPs) from Helianthus annuus L. leaf extracts in ethyl acetate (AgNPEa) and methanol (AgNPM), along with antibacterial and antioxidant properties of the resulting nanoparticles. The phytochemical analysis of the ethanol and ethyl acetate extracts was done. Characterization (UV-visible (UV-Vis), Fourier transform infrared (FT-IR), energy dispersive X-ray (EDX), scanning electron microscopy (SEM), X-ray diffraction techniques (XRD) and FTIR), antioxidant and antibacterial potential of the synthesised AgNPs were done. The two extracts showed no cardiac glycosides. A change in colour of the silver salt solution, showing a maximum UV-vis absorbance at 450 nm for AgNPMHa and 500 nm for AgNPEaHa. The SEM and TEM revealed a spherical shape having about 26.8 ± 9.4 nm and 22.3 ± 6.8 nm size. The EDX showed a high silver content of 69.35% in AgNPMHa and 72.40% in AgNPEaHa while XRD showed planes of pure silver ions. FTIR analysis the capping and stabilization of nanoparticle. Hydrogen peroxide, reducing power and total antioxidant activity increased dose-dependently (55 ± 23%, 63%, and 57% for AgNPEaHa and 57.03 ± 17%, 69.62 ± 21%, and 56% for AgNPMHa at 400ul) and both susceptible to Escherichia coli. The results confirmed that Helianthus annuus is a potential biomaterial for synthesizing AgNPs which can be exploited for its antioxidant and antibacterial activity

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