ghanaopendata/ghanaian-research-english huggingface dataset:
Beta-Glucan Content In Tropical Maize Genotypes: Extractability, Structural Analysis, Rheology And Function

Beta-glucan is a complex soluble dietary fiber with (1→3),(1→4)-β-D linkages in a repeating unit of cellotriosyl, cellotetraosyl glucose chains interspersed with β-(1→3) linkages, found mainly in the cell walls of cereal endosperm and specifically in oat and barley. Beta-glucan is known to impart some health benefits to consumers including lowering of blood glucose and cholesterol level, as well as prevention of colon cancer. Beta-glucan research has concentrated on oat, barley and wheat. The absence of these cereals in tropical West Africa necessitates an exploration into the use of cereals of tropical origin such as maize to identify their potential of being good sources of β-glucan. The objectives of this study weretoscreen tropical maize genotypes for β-glucan content,and evaluate their structure and functionality in food systems. In the present study, β-glucan contents ofseventeen Ghana maize genotypesviz., ‘Mamaba’, ‘Suwan 1 QPM’, ‘Obatanpa GH’, ‘Omankwa’,‘GH9’, ‘Catete’, ‘Dodzi’, ‘Okomasa’, ‘Aburohemaa’, ‘Abontem’, ‘SotuBaka’, ‘Dorke’, ‘Akposoe’, ‘Abeleehi’, ‘Safita 2’, ‘Ohawu Local’ and ‘Golden Jubilee’ were analyzed using hot water, acid, alkaline and alcohol-enzyme based extraction procedures. Gum content varied by extraction method and genotype. Hot water and alkaline procedures produced low extractability demonstrating gum yield ranging from 0 to 2.29 % and 0 to 22.12 %, respectively. Significantly higher gum yields were produced by the acid and alcohol-based enzyme extraction procedures. The acid treatment produced a mean yield of 45.97 % which was not significantly different from 39.97 % yield obtained by the alcohol-enzyme treatment (P>0.05). With regard to genotype, hybrid maize varieties contained the highest mean gum content of 31.83 % while the landraces contained lowest value of 19.11 %. Genotypes having the highest β-glucan content were 1.4 % for ‘Obatanpa GH’, 1.68 % for ‘Abeleehi’ and 2.56 % for ‘GH 9’. Gum content of kernels had positive correlations with protein and fibre but negative correlation with nitrogen free extract. Minimal levels of impurities in the form of starch, protein and fat were present in the gum isolates. Structural analysis of maize β-glucan by 13CNuclear Magnetic Resonannce produced chemical shifts similar to that of standard oat and barley spectra and characterized by slight displacements as upfield and downfield shifts. The aniline blue fluorescence microscopy revealed that β-1→3 branching in maize β-glucan was less than that in oat and was genotype dependent. ‘Abeleehi β-glucan demonstrated higher β-1→3 branching than ‘Obatanpa GH’ β-glucan. The flow behavior of 10 % maize β-glucan dispersion was pseudoplastic and non-Newtonian just as 5 % oatβ-glucan. High water binding capacity of maize β-glucan up to 232 % makes it a suitable ingredient in food products which should resist syneresis. Maize β-glucan was found to be a good fat replacer, replacing up to 15 % of fat in pie crust without compromising sensory attributes.

Source: KNUST
Bifurcation analysis of the Ramsey-Cass-koopmans economic growth models

In this thesis, we review dynamical systems in general, the formulation of Ramsey-Cass-Koopmans (RCK)growth model with exponential growth of labour (population) and Ramsey-Cass-Koopmans model with logistic growth rate of labour developed by Brida and Accinelli (2007) are outlined with in the form of first other system of nonlinear equations...

Source: KNUST
Big And Connected Data Analysis With Graph And Relational Databases Using Collaborative Filtering Technique

Over the years systems or applications in existence have been able to work seamlessly with relational databases. Applications such as point of sale, hospital management systems, Human resource applications, payroll systems, banking with relational databases banking systems just to mention a few are powered by relational databases with minimal to entirely no issues because most the relationships amongst entities in these systems are mostly not complicated or highly connected. In the same vein relational database systems have been able to handle large amounts of data and transactions emanating from everyday operations of these systems. In summary the relational database was very effective in dealing with the problems applications available were solving. In these modern times the influx of social media platforms, map and navigations systems, geospatial information systems, recommendation engines ,referral systems and the likes have turned the tide for systems and the databases behind them to support, manage and model mostly semi/unstructured, connected and their complex associations amongst data elements. This study looked at such data with the concept of recommendations to test whether relational databases were still performing well with the current trends on connected data or the NoSQL paradigm making inroads in the technology space had a point when they say ―they are the database paradigm for the future‖. An experiment was therefore performed with a relational and graph database to ascertain this analogy. Key performance indices (KPI) such as runtime, storage, schema flexibility, query complexity and general operations of each database paradigm were tested with the concept of making recommendations to a number of people in the database based on how their associated with each other. Each paradigm was put on similar test against the above KPI‘s and the graph database seemed to have an urge over the relational database in the result and analysis of the figures that were obtained from the experiment

Source: KNUST
Bio - prospecting for effective rhizobia isolates for Soybean production in Ghana

Biological nitrogen fixation is considered an inexpensive means of soil fertility replenishment and as such needs to be exploited. Wild – legume rhizobia have been reported to form successful symbiosis with some important grain legumes like soybean. Hence this study sought to obtain wild – legume rhizobia (indigenous isolates) from wild and uncultivated legumes such as Desmodium spp, Centrosema spp, Mimosa spp, Crotolaria spp, Calopogonium spp and Ceasalpinea spp. A bio - prospecting activity was carried out to collect nodules from uncultivated legumes in parts of Ashanti and Northern regions of Ghana. After culturing and characterization of the indigenous isolates in the microbiology laboratory (SRI), 85 isolates showed characteristics similar to rhizobia on YMA (CR and BTB) media: 65 isolates showed fast growing character while 20 were slow growers. The 85 indigenous isolates were further tested for their infectivity (ability to nodulate legumes) on soybean in sterile river sand and non – sterile soil media. Eleven of the isolates were infective. Symbiotic effectiveness index, SEI showed that isolate NAG 218 was highly effective (SEI > 80), while NAG 150, NAG 155, NAG 180 and NAG 181 were effective (SEI between 50 – 80%) and NAG 152, NAG 168, NAG 170, NAG 171, NAG 173 and NAG 211 were classified as lowly effective (SEI between 35 – 50%). The symbiotic potential of the isolates on the promiscuous soybean varieties in non – sterile soil showed that isolate NAG 152 performed relatively better (11%) than the Legumefix strain. NAG 171 on the other hand produced statistically similar nodule dry weight as Legumefix strain. Shoot dry weight produced by NAG 168 and NAG 211 were statistically at par with the shoot dry biomass of Legumefix strain and USDA 110. Effective isolates at high cell concentration levels (108 and 104 –CFU) were not competitive. Isolates NAG 152, NAG 168, NAG 171 and NAG 211 showed potentials for fixing nitrogen thus increasing the possibility of obtaining local strains for soybean production.

Source: KNUST
Bioaccumulation Of Heavy Metals And Essential Minerals In Two Tuna Species, Yellow Fin And Skip Jack

ABSTRACT The free social media has made it possible for health consciousness to be discussed, making people aware of the hazards in food in Ghana and the world around. People are gradually becoming concerned about what they consume. This has contributed to lots of research work into the quality of incoming materials used for the processing of foods. This study was carried out to establish the variability of mineral distribution in yellow fin and skip jack tuna, from the Atlantic Ocean; these species are highly used in the fish canning industry. Three different sample weights per fish species of 1.5 – 1.8; 1.9 – 3.4; and > 3.4 kg, representing a total 36 samples were collected from landing vessels at the Tema main or Fishing Harbours from August to December 2015 and in April 2016. Samples were analysed using the Varian AAS (AA240FS Model) for the variability of three heavy metals; Lead (Pb), Cadmium (Cd), and Mercury (Hg), and also for two essential minerals; Zinc (Zn) and Selenium. Laboratory analysis were carried based on IAEA – 407 dry weight basis. Data obtained were fitted to models that explained the behaviour and responses within the limits of the variables that were studied using the RSM (D- Expert, 2015). Optimization was performed to predict the optimum conditions for minimum heavy and maximum essential minerals in each sample. The study showed desirable months and size to obtain minimum heavy metal and essential minerals in Yellow fin and Skip Jack September 2015 and April 2016 respectively. Results obtained also showed that there exists a variability in the distribution of minerals in YF and SKJ from the Atlantic Ocean. However, the distribution did not follow a sequential order of less mineral to less weight fish or vice – versa.

Source: KNUST
The bioactive constituents of “chlorophora excelsa” a Ghanaian timber species

Thin-layer chromatography of ethanol extract (E1) of the heartwood of Chlorophora Excelsa revealed three (3) components. Fractionation of the ethanol extract was carried out by hydrolysis followed by batch separation with separators funnel. Fractions were monitored by their bioactivity/ microbial activity and one fraction E11 showed the highest activity when tested against brine shrimp Pure E11, was extracted and was found to be phenolic.Acetate derivative (D11) of the phenolic extract (E11) was prepared and was identified by spectra and chemical methods as chlorophrin, (a pinosylvin analogue), which had hitherto been identified in Iroko tree by Grundon and King [8]

Source: KNUST
Bioactivity guided isolation and characterisation of the antimicrobial principles of Mammea Africana S. (Guttiferae)

This thesis is a report on the bioactivity guided isolation and characterisation of the antimicrobial principles of Mammea africana S. (Guttiferae) a large evergreen tree found in the tropical rain forest of Ghana, specifically in the wetter mixed deciduous forest of Ashanti Region. Mammea africana is known throughout the tropics and subtropics and is used to treat dermal infections like boils, itches and crawcraw. It is also used in the treatment of rheumatic pain, whooping cough and to cleanse ulcers. The study has shown that the bark of Mammea africana exhibits antimicrobial properties in vitro. Preliminary bloactivity studies of the crude ethanollc extract showed activity on test organisms. A petroleum ether fraction that was obtained by fractionation from the crude ethanolic extract also showed tremendous activity on test organisms - as demonstrated by the values of the zones of inhibition. The aqueous fraction left after the extraction with the petroleum ether, however, had no activity. Preliminary TLC analysis of the petroleum ether fraction showed four constituents all of which were isolated by column chromatography and tested for their activities on the test organisms. The third major constituent, Mammea B/BB (R1) was found to be the most active. The three other compounds designated as R2, R3 and R4 were established to be coumarins.R2, R3 and R4 could not be further identified due to paucity of data. They were found to have varying degrees of antimicrobial activity on test organisms though weaker than Mammea B/BB. Comparing their MIC values, R2 was the most active, followed by R3 and R4.

Source: KNUST
Bioactivity guided isolation and characterization of the antimicrobial constituents of Mammea Africana S. (Guttiferae) and Spathodea Campanulata B. (Bignoniaceae)

Investigation has been conducted on the stem-bark of Mammea africana (Guttiferae) and Spathodea campanulata (Bignoniaceae), reputable medicinal plants that are used in traditional medicine for treating various infectious conditions such as boils, infected wounds and ulcers. The aim was to establish the scientific basis for their use and also to isolate some of the compounds responsible for the antimicrobial activity. These plants are found in tropical Africa including Ghana where they are found in the deciduous forest of the Ashanti Region. The ethanolic and petroleum ether extracts from the stem bark of M africana showed antibacterial activity against Escherichia coli, Bacillus subtillis, Pseudomonas aeruginosa, Clostridium histolyticum and Staphylococcus aureus. Four coumarins, one of which was characterized as mammea B/BA, were isolated by chromatography from the petroleum ether extract of this plant. These compounds showed antibacterial activity against the above-mentioned bacteria. Their activity against Candida albicans was, however, negligible. The ethanolie extract also yielded the ubiquitous plant sterols, 13-sitosterol and stigmasterol. The petroleum ether, ethyl acetate and ethanolic extracts of the stem bark of S. campanulata also showed significant activity against the above-mentioned bacteria. In addition these extracts showed activity against the yeast-like fungi, Candida albicans. The various chromatographic fractions obtained from the ethyl acetate and petroleum ether extracts also showed varying activities against the micro-organisms. Though no compound was characterised from S. campanulata the extracts and their fractions showed antimicrobi& activities which validates its use in the treatment of some infectious conditions.

Source: KNUST
Bioactivity guided investigation of the stem bark and leaves of Voacanga Africana (Apocynacea)

Plants since time immemorial have been used for their beneficial effects such as antimicrobial, antioxidant and bacterial resistance modulation. This project presents work on Voacanga africana (Apocynaceae) a local Ghanaian plant, in which the leaves and stem barks were screened for antioxidant and resistant modulatory properties. The antioxidant assay was determined using DPPH scavenging, total phenolic count and total antioxidant capacity. The antimicrobial and bacterial resistance modulation activity was determined using the broth dilution and agar well diffusion methods using S. aureus, E. coli, S. typhi, P. auregenosa, B. subtilis and Candida albicans. Further work was performed by looking at the phytochemical constituents of the extracts and isolates. The antioxidant activity as seen from the DPPH assay was concentration dependent with the methanolic extract of the stem bark showing more activity than the leaf, with Ic50 of 70 and 1605 respectively, whilst that of the standard (ascorbic acid) was 6.980. Antioxidant activity was also found to be very closely related to the amounts of phenolic compounds which were present in both extract from the correlation plots obtained after the total phenolic and antioxidant assays. The leaf extract also showed no antimicrobial activity whilst the stem bark extract showed very significant activity against the chosen microorganisms, with MIC’s of 4mg/ml against a majority of the microorganisms. Also in this work, isolates were chromatographically obtained from the methanolic extracts and bulked into six fractions labelled VAMA01, VAMA02, VAMA03, VAMA04, VAMA05 and VAMA06. Amongst the isolates, VAMA01 and VAMA02 showed significant activity when combined with most used antibiotics including amoxicillin. Most significant result was when 3mg/ml of the extract VAMA01 was combined with 4mg/ml of amoxicillin against E. coli when the individual MIC’s were 4mg/ml and 32mg/ml respectively. Also combining 3mg/ml of VAMA02 with 8mg/ml of amoxicillin was enough to inhibit the growth of P. aeruginosa where the initial MIC’s were 8mg/ml and 64mg/ml respectively. Thus the extracts VAMA01 and VAMA02 were found to possess very significant resistance modulatory activity.

Source: KNUST
Bioactivity Guided Isolation and Characterisation of Acaricidal Principles of Plumbago Zeylanica L. (Plumbaginaceae)

This thesis is a report on the bioactivity guided isolation and characterisation of acaricidal principles of Plumbago zeylanica L. (Plumbaginaceae) a shrubby plant found in the coastal areas of Ghana. Plumbago zeylanica is known throughout the tropics and the sub-tropics and used to treat parasitic skin infections and piles. It is also used to treat worm infestation and as an abortifacient. The study has shown that the roots of P. zeylanica exhibit acaricidal properties in vitro.Preliminary bioactivity studies of the crude methanolic extract showed activity on tick larvae. An ethyl acetate fraction that was made from the crude extract also showed activity on the ticks while the aqueous fraction left after the extraction with the ethyl acetate had no activity. Preliminary TLC analysis of the ethyl acetate fraction showed five constituents all of which were isolated by column chromatography and tested for their activities on ticks. The major constituent, plumbagin was found to be the most active against the ticks. Two other constituents which were identified as β- sitosterol and stigmasterol, were found to be weakly active. Comparison of the chemical profiles of the root, stem and leaf revealed the occurrence of plumbagin in the different organs of the plant but most in the root (2.00% w/w) and least in the leaf (0.028% w/w).

Source: KNUST
Bioactive constituents from the Ghanaian medicinal plant Chlorophora regia and its root endophytic fungus JK10.

The extracts of the Ghanaian medicinal plant Chlorophora regia A. Chev (Moraceae) has been used for the treatment of various ailments in traditional medicine including burns, wounds, snake bite, wasp bite. A search through the literature, however, revealed there were no available data on the phytochemical composition of the plant. Therefore, the main objective of this study was to isolate, characterize and evaluate some biological activities of secondary metabolites from the stem bark of the plant and further investigate the endophytic community harbored in the inner tissues of the plant. Extensive phytochemical investigation of the stem bark resulted in the isolation and characterization of four new metabolites, regiafuran A–C and 6–prenylated–3,5,7,4ʹ–tetrahydroxy–2ʹ–methoxyflavonol in addition to fifteen known compounds. The isolated compounds were tested for their free radical scavenging activities. Regiafuran A–B, mulberrofuran Y, kuwanol E and 5,7,4ʹ–trihydroxy–2ʹ–methoxyflavanone demonstrated significant free radical scavenging activities with IC50 values of 1.9 μg/ml, 2.4 μg/ml, 2.2 μg/ml, 2.1 μg/ml and 1.8 μg/ml respectively. An unidentified endophytic fungus, JK10, was isolated from the root of C. regia. Twelve compounds including seven new 7–desmethyl derivatives of fusarin C and five known compounds were isolated from the endophytic fungus, JK10. The planar and relative configurations of the new compounds were elucidated by combined spectroscopic analyses of their UV, IR, HRESI–MSn, ECD and NMR data. The absolute configuration of solaniol was established for the first time by X–ray diffraction analysis of a single crystal. The antibacterial activities of the isolated compounds were evaluated. 7–desmethyl fusarin C–22/23 and 7–desmethyl fusarin C–25 exhibited remarkable activity at concentrations of 10.0 μg/mL against the soil bacterium Acinetobacter sp. BD4 comparable to the reference standard streptomycin. All the tested compounds demonstrated activity against the environmental strain of E. coli. Based on the results it could be proposed that the endophytic fungus, whose origin is from the roots, contributes a chemical–mediated defensive mechanism to the host plant against iii invading specific soil and environmental bacterial pathogens. This may confirm the existence of a unique cost–benefit endophyte–plant association. The spatial distribution of three kaurane diterpenes, xylopic acid, ent–kaur–16–en–19–oic acid and 15–oxo–ent–kaur–16–en–19–oic acid, in the fruits of Xylopia aethiopica (Dunal) A. Rich (Annonaceae) were visualized by MALDI–HRMS imaging techniques. The distribution of the compounds was predominantly in the pericarp region of the fruit with non-detectable levels in the seed.

Source: KNUST
Bioavailability of locally manufactured co-trmoxazole tablets

Pertinent bioavailability and bioequivalent data are required by Pharmacist, Physicians, and others who prescribe, dispense or purchase drug products. This is because a plethora of drug products containing the same amount of active ingredients have flooded the Ghanaian market. The bioequivalence of generic co-trimoxazole and reference (Septrin- GlaxoWeilcome) was compared in six healthy subjects in a crossover design using the amount of the unchanged sulphamethoxazole excreted in urine over 24 hours. The generic product was from Phyto-Riker (GIHOC). It was designated in the study as S. The reference product was designated as R and it was purchased from S. K. Osei Pharmacy, a retail pharmacy shop at Adehyeman Gardens opposite the Methodist Book Depot in Kumasi. ln vitro dissolution test was also carried out. With reference to the product R, the relative bioavailability of product S was 109.23. An HPLC method for determining accurately and precisely sulphamethoxazole in urine was tried and used. Phermacokinetic variables that were tested to characterize bioequivalence were the mean cumulative amount of unchanged sulphamethoxazole excreted, the mean peak rate of urinary excretion, and the time for peak urinary excretion. In order to ensure that any difference observed in the in vivo study among the products were not due to sample identity and formulation factors, pharmacopoeial identification tests, uniformity of weight, friability and hardness tests, dissolution and percent content assay were performed on all the drug products. For all tested products, the results of sample identification, uniformity of weight, dissolution, friability test and hardness test as well as percent content assays were within acceptable limits of BP 2000 and USP XXII (1980). Pharmacokinetic variables tested showed no significant difference between the products S and R. The generic product was therefore fully bioequivalent with the reference product. An HPLC separation and resolution could be achieved with a mobile phase combination of ethanol and 70% ammonium perchiorate ( 95 : 5) on a reversed phase column at ambient temperature. Elution was socratic with UV detection wavelength of 254nrn Internal standard calibration method was used for quantification with Salicylic acid as the internal standard. Mean retention times for trimethoprim, sulphamethoxazole and salicylic acid were 3.4 ± 0.125 mm, 3.8 ± 0.075 mm, and 4.5 ± 0.125 mm respectively. Assaying the two products with the new HPLC method and the official BP 2000 method yielded t-values of 1.52 and 0.858 in test and reference respectively. This means these two methods were comparable at 95% confidence level. Also the percentage content each of active ingredient in test and reference samples by both methods fell within acceptable limits of BP 2000 and the USP-XXII (1980) limit.

Source: KNUST