ghanaopendata/ghanaian-research-english huggingface dataset:
Phytochemical screening, antimicrobial and antioxidant properties of assorted Carica papaya leaves in Ghana

The bioactive compounds of the leaves of Carica papaya; solo and solomix were extracted using ethanol and n-hexane, and investigated for the presence of secondary metabolites. Both ethanol and n-hexane extracts revealed the presence of alkaloids. Flavonoids, glycosides and saponins were present in only the ethanol extract whereas tannins were present in the n-hexane extract. The bioactivities of the leaf extracts were attributed to their phytochemical constituents. Antimicrobial activity of the extracts were determined against some human pathogenic bacteria and fungi such as Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae, Bacillus subtilis and Candida albicans using the agar well diffusion and broth dilution methods with the polar extract being more effective. The ethanol extract demonstrated a significant broad-spectrum antimicrobial activity against both gram-positive and gramnegative bacteria, with the highest activity having a zone of inhibition of 10 mm. Antioxidant activity was determined using the DPPH assay method and the absorbance measured using UV- visible spectrophotometer with ascorbic acid as control. The antioxidant activities of solo and solomix showed IC50 of 1.465x10-2 and 1.364x 10-2 respectively. This study demonstrates the efficacy of ethanolic leaf extracts of C. Papaya as an alternative antibiotic for the development of newer antibacterial agents.

Source: KNUST
Phytochemical screening and bioactive properties of the stem bark extracts of Allanblackia Parviflora (Chevalier) (Clusiaceae)

The phytochemical constituents, antioxidants, antimicrobial and anti-inflammatory activities of the methanolic, aqueous and pet- ether extracts of the stem bark of Allanblackia parviflora have been studied in this work with the aim of exploring the medicinal properties of the plant in Ghana. The results obtained from the qualitative phytochemical screening indicated the presence of alkaloids, tanins, flavonoids, cardiac glycosides, reducing sugar, triterpenoids, anthraquinones, saponins and phytosterols and the absence of cyanogenic glycosides. The antimicrobial assay employed Agar-well diffusion and Micro broth dilution methods against 10 microbial strains (i.e. one fungus, five gram-negative and four gram-positive bacteria) using Ciprofloxacin as the reference drug. The methanolic extract exhibited the highest activity against E. faecalis with zone of inhibition 20 mm and MIC of 2.5 mg/ml. Pet-ether extract on the other hand was inactive against test microbes. Anti-inflammatory properties of the extracts employed the Carrageenan induced paw model in a week old chicks. The various extracts at 30, 100 and 300 mg/kg exhibited prominent therapeutic anti-inflammatory properties with methanol recording the highest activity at oedema inhibitory percentages of (42.92%, 56.93% and 66.01%) and (49.26%, 51.41% and 59.05%) for therapeutic and prophylatic studies respectively. Followed by aqueous (28.61%, 46.60% and 56.93%), (29.27%, 39.20% and 48.24%) and pet-ether (34.92%, 45.38% and 45.99%), (33.42%, 36.05% and 42.53%) respecitively. Antioxidant assay also employed DPPH scavenging potential, TPC and TAC for the assessment. The results however presented the methanolic extract as most potent with EC50 value of 0.03341 mg/ml, TAE of 212.85±0.311 mg/g and AAE of 77.72±0.549 mg/g for DPPH Scavenging potential, TPC and TAC respectively. These results therefore provide for the first time scientific bases for the folkloric use of A.parviflora in managing inflammations, microbial infections and some tropical diseases.

Source: KNUST
Phytochemical screening, antimicrobial, antioxidant and anti-inflammatory activities of methanolic, aqueous and pet ether extracts of the leaves of Allanblackia Parviflora (A. Chevalier)

The research has investigated the phytochemical constituents, antimicrobial, anti-inflammatory and antioxidant activities of various extracts of Allanblackia parviflora. The Phytochemical screening revealed the presence of flavonoids, tannins, reducing sugars, alkaloids glycosides, anthraquinones, terpenoids, steroids and cardiac glycoside with the absence of saponins. Antimicrobial investigation involving agar well diffusion and broth dilution methods were used for preliminary examination and MIC determination respectively. The aqueous extract showed the highest activity against Candida albicans with zone of inhibition of 15.00 mm and MIC of 10 mg/ml. The methanolic extract showed activity against Staphylococcus aureus with a zone of inhibition of 12.00mm and MIC of 5 mg/ml with no activity from pet-ether extract. Antioxidant activity of the extract was established using DPPH scavenging assay, total antioxidant capacity and total phenol content. The extracts were found to possess DPPH scavenging activity with IC50 of 48.97μg/ml for the methanolic extract, 158μg/ml for the aqueous extract and1479 μg/ml for the pet ether extract. The standard (ascorbic acid) gave an IC50 of 29.91μg/ml. Total antioxidant capacity values obtained were 14.7953 mg/g, 13.7681 mg/g and 12.6185 mg/g for the methanolic extract, pet ether extract and aqueous extract respectively. Total phenol content values were 21.515mg/g for methanolic extract, 19.1836mg/g for pet ether extract and 15.66mg/g for aqueous extract. An in vivo carrageenan induced paw oedema method was used to assess therapeutic and prophylactic anti-inflammatory activity of the extracts in chicks. The methanolic extract exhibited the highest anti-inflammatory activity for therapeutic (300mg/kg -57.2%, 100mg/kg -54.19% and 30mg/kg-53.16%) and, prophylactic (300mg/kg-54.60%, 100mg/kg-51.20% and 30mg/kg -37.52%) assessment at the various concentrations respectively. Pet ether extract and aqueous extracts also gave significant anti-inflammatory activities at percentages of (52.30%, 30.00% and 25.43%), (45.41%, 35.96% and 23.00%) for prophylactic and (.12%, 47.00% and 25.00%), (50.90%, 46.29% and 45.41%) for therapeutic respectively

Source: KNUST
Phytochemical screening, brine shrimp lethality test and pesticidal action of some indigenous plants

An attempt has been made at establishing the scientific basis for the traditional use of Some Ghanaian plant products as pest control agents for stored food grains. Samples (leaves/seeds) of fifteen different plants were collected, dried and ground into tine powders. Extractions were performed using pet-ether and ethanol as solvents. Steam distillation was also used to obtain the oil from Cymbopogan winterianus leaves. The brine shrimp lethality bioassay was used to determine the toxicities of the extracts, by estimating the LC50 values. Toxicities of Cymbopogan winterianus(oil), Azadirachta indica(oil), Cassia alataa(ethanol extract) and Allium sativum(slurry ) were very high whilst toxicities of Jatropha curcas(ethanol extract), Celtis mildbraedii(ethanol extract) and Blighia sapida( pet-ether extract) were very low. Studies on the influence of eight of the plant extracts and one synthetic insecticide on the storage of cowpea and maize seeds for three months were conducted at the Crops Research Institute, Kumasi. The results indicated that some plant extracts had significant effects on the total number of insects (Callosobruchus rnaculates/Sitophilus zeamais) killed (highest for Cvmbopogan winterianus) damaged seeds (highest for Griffornia simplicifolia. no damage for Cymbopogan winterianus) and population build-up (least for Cymbopogan winterianus) and could compare to synthetic insecticides. From phvtochemical studies, the plants showed different classes of secondary plant metabolites. Chromatographic studies on the ethanol extract of Cassia alata leaves produced four fractions P1, P2, P3 and P4. Fractions p1 and p3 isolated were chemically found to the carotenoids. Fraction p2 was chemically found to be a triterpenoid whilst fraction P4 was chemically found to be an anthraquinone.

Source: KNUST
Phytochemical, Antimicrobial, and Antioxidant constituents of the stem barks of trichilia monadelpha (thronn) j.j. de wilde and trichilia tessmannii (harms) both of the family meliaceae

In this present work, the stem barks of two medicinal plants, Trichilia tessmannii (Harms) and Trichilia monadelpha (Thonn) JJ De Wilde both of the family Meliaceae were screened for their phytochemical constituents and evaluated for their antimicrobial and antioxidant activities with the sole objective of isolating the active principles present. The phytochemical investigation revealed the presence of plant secondary metabolites such as; Tannins, Reducing sugars, Anthraquinones, Alkaloids, Saponins glycosides, Cardiac glycosides, Terpinoids, Cumarins and Phytosterol. The antimicrobial activity was determined by broth dilution method using standardized bacteria suspensions of Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and the fungus, Candida albicans. Broad-spectrum antimicrobial activity was observed for all extracts except the petroleum ether extract of T. tessmannii. A minimum inhibitory concentration (MIC) of 0.625 mg/mL was determined as the highest activity for the ethyl acetate extract of T. tessmannii against Pseudomonas aeruginosa and Candida albicans. Lowest MIC of >10 mg/mL was however recorded by the petroleum ether extract of T. tessmannii against Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. Antioxidant activity was determined by the use of DPPH free radical scavenging assay, Total phenol content assay and Total antioxidant capacity assay on the total crude methanol extract of the stem bark. The total crude methanol extract was found to possess DPPH free radical scavenging activity of EC50 values 0.0207 mg/mL and 0.0099 mg/mL for the extracts of T. tessmannii and T. monadelpha respectively and 0.004806 mg/mL for the ascorbic acid used as the reference drug. The values obtained from the estimation of the Total antioxidant capacity assay were 444.7 ± 28.58 mg/g of ascorbic acid and 324.40 ± 20.41mg/g of ascorbic acid for T. tessmannii and T. monadelpha respectively, and the Total phenol content values v for T. tessmannii and T. monadelpha were 970.2 ± 78.69 mg/g of tannic acid and 884.2 ± 61.00 mg/g of tannic acid respectively. These findings provide scientific justification for the use of the stem barks of T. tessmannii and T. monadelpha, in various traditional medicines, for the treatment and management of diseases associated with oxidative stress and infectious conditions. The chromatographic separation of extracts done so far was by open column silica gel chromatography using the gradient elution method. Chromatographic separation of the ethyl acetate extract of the stem back of T. Monadelpha (TME) has yielded an isolate ‗A 1 ‘, which is yet to be further purified and characterized.

Source: KNUST
Phytochemical, Antioxidant And Anticancer Evaluation Of HydroeThanolic Extracts Of CroTalaria Retusa (L.) And Codiaeum Variegatum (L.) A. Juss Parts.

For centuries now, plants have served as a great source of compounds with pharmacological properties. Some plants like weeds and ornamentals, however, have not been fully exploited for their medicinal value. In this research, the phytochemical, total phenolic content, antioxidant and antiproliferative effect of Codiaeum variegatum, a common ornamental plant used in some parts of the world for treating psoriasis and Crotalaria retusa, a weed reported to have potential to fight tumours were assessed. Standard methods that have been accepted internationally, such as the MTT cell viability and the DPPH assays among others were used to determine the selected properties of both plants. The leaf and stem bark of C. variegatum both showed the presence of general glycosides, tannins, alkaloids, flavonoids and sterols. The seed, pod, flower, stem and leaf of C. retusa were all found to contain saponins, general glycosides, tannins, alkaloids and sterols. Anthracene glycosides were absent from all the two plants. The stem bark of C. variegatum exhibited stronger antioxidant activity with an EC50 value of 0.053±0.004 mg/mL and total phenolic content of 163.0±3.323 mg GAE/g of extract, as compared to its leaf which had EC50 value of 1.396±0.073 mg/mL and total phenolic content of 53.8±0.721 mg GAE/g of extract. With respect to C. retusa, the leaf was found to have the highest concentration of phenols (67.35±1.153 mg GAE/g of extract) and the best free radical scavenging activity with an EC50 value of 0.222±0.004 mg/mL. All the extracts induced cytotoxicity in a dose dependent manner. The antiproliferative effect of C. variegatum indicates that among the components of the plant, the stem bark is most effective in killing the breast (MCF 7), prostate (PC 3) and leukemic (Jurkat) cancer cells. Similarly, the study revealed that the stem of C. retusa exhibited the highest cytotoxicity against the selected cancer cells. However, extracts of both plants were observed to be non-selective towards cancer cells since they were equally toxic to the normal human liver (WRL 68) cells. The Hoechst staining for nuclear morphological changes and flow cytometry assays were used to confirm the apoptotic nature of the C. variegatum stem bark extract at 20 and 40 µg/mL. Further fractionation of the stem bark of C. variegatum and stem of C. retusa into petroleum ether, chloroform, ethyl acetate and hydroethanolic fractions resulted in reduction of cytotoxicity against breast (MCF 7), liver (HepG2) and leukaemic (Jurkat) cancer cell lines for almost all the fractions of both extracts. The chloroform fraction of C. variegatum stem bark, however, recorded an increase in cytotoxicity with an IC50 of 44.71±0.44 µg/mL against Jurkat. These results confirm the cytotoxicity of both plants. Further studies are required to identify the active principle

Source: KNUST
PhytocPhytochemical Composition Of Ipomoea Batatas And Moringa Oleifera leaves and crackers from underutilised flours. hemical Composition Of Ipomoea Batatas And Moringa Oleifera Leaves And Crackers From Underutilised Flours.

Great emphasis is being placed on the consumption of food that will not only provide nutrients to the body but also help in the prevention of diseases such as cancer, cardiovascular diseases, and age-related macular degeneration as well as malnutrition. People are being encouraged to eat fruits and vegetables which have antioxidative and bioactive compounds that help prevent molecular damage caused by oxidation. Ipomoea batatas and Moringa oleifera are two indigenous vegetables whose nutritional potential though felt in other parts of the world are not known in Ghana. Thus the need for the analysis for the nutritional and phytochemical potential of the new varieties of these vegetables found in Ghana as well as their use in product development. Phytochemical analysis of the leaves was carried out using standard methods of analysis. The results obtained showed that Moringa oleifera had higher levels of crude protein, crude fibre, crude fat, iron, calcium and beta-carotene. The Ipomoea batatas samples, however, had higher levels of crude ash, total carbohydrate, total calorie, moisture and total phenolics. Cream cracker were developed from cassava and sweetpotato flour incorporated with these leaves using wheat flour as the control. Sensory evaluation of the cream crackers developed showed that they have good sensory properties and since the cassava and sweetpotato flour crackers do not contain gluten, they can be consumed by those who are gluten intolerant.

Source: KNUST
Phytoremediation of heavy metal contaminated soil using Thelypteris accuminata (Houtt.) C.V. Morton and Nephrolepis exaltata (L.) Schott

Phytoremediation provides an alternative remediation method for clean-up of heavy metal contaminated soils. The application is especially important in tropical developing countries due to its cost effective and aesthetically pleasing solution. In this study two ferns Thelypteris accuminata and Nephrolepis exaltata were evaluated in potted experiment to examine their phytoremediation potential using contaminated soil from the Sansu Talings Dam of AngloGold Ashanti, Obuasi Mine, Ghana. Four different soil treatments were used; raw tailings material, uncontaminated topsoil, mixtures of tailings and topsoil at two different ratios (1:0, 0:1, 1:1 and 1:3). The experiment was laid out in a completely randomised design with three replicates at the Plant House Nursery of the Department of Theoretical and Applied Biology, KNUST. Samples of plants were harvested at 30 days (1st harvest), 60 days (2nd harvest) and 90 days (3rd harvest). The concentrations of three heavy metals (As, Pb and Cd) were analysed in samples of the soils and plant organs (rhizoids and fronds) before transplanting and after harvest using the Atomic Absorption Spectrophotometer. The mean differences in concentration of the metals in the rhizoids and fronds were separated using Tukey’s B multiple comparison test (p<0.05). The bioaccumulation potential of heavy metals in the plants was determined from the bioaccumulation and translocation factors. The total mean content of heavy metals (As, Pb and Cd) varied between plants and treatments with As being most accumulated (41.30 mg/kg) by Nephrolepis exaltata cultivated in tailings only. Arsenic levels in the tailings only (1:0) and topsoil + tailings (1:1) exceeded the WHO recommend standard for As in agricultural soils; while Pb and Cd levels were below the standards. The concentrations of all metals were higher and significantly different in the rhizoids than in the fronds. The translocation factor showed that Thelypteris accuminata is a good phytotranslocator for Cd (8.06) while Nephrolepis exaltata is best for As (5.17). The highest bioaccumulation factor was recorded for Cd in the topsoil with Thelypteris accuminata having 44.29 whilst Nephrolepis exaltata had a ratio of 60.77. The percentage reduction of heavy metals in the soil among the plants was significantly different during the three harvest periods. In the treatment soil, topsoil + tailings (1:3) 95.23% reduction was recorded for Cd by Thelypteris accuminata as against 98.21% reduction of Cd by Nephrolepis exaltata. The microbial counts in the soil samples after each harvest were significantly different for the treatments. The different levels of heavy metals accumulation by the two species of ferns, indicate their tolerance to high levels of heavy metals, preferably with Nephrolepis exaltata. The capacities of these ferns to accumulate and translocate heavy metals provide useful information for their metal exploitation as phytoremediating species for the remediation of contaminated mine sites.

Source: KNUST
Phytoremediation of heavy metal contaminated soil using Chromolaena odorata and Lantana camara

Phytoremediation, the use of plants specifically chosen for the rehabilitation of polluted lands, is an emerging biotechnology for the removal of heavy metals from contaminated sites. Though the technology is now established in temperate regions and industrialized countries, its use in the tropics and developing countries is very limited. The phytoremediation potential of two commonly found high biomass weed species, Chromolaena odorata and Lantana camara was evaluated in a pot experiment using heavy metal contaminated soil from the Sansu tailings dam of AngloGold Ashanti Ghana Limited in Obuasi, Ghana. Soil treatments included tailings soil and tailings soil amended with NPK fertilizer. The concentrations of six heavy metals (As, Fe, Cu, Pb, Zn and Cd) were analyzed in soil and plant tissues at two harvest times using the Atomic Absorption Spectrophotometer. At the end of the first harvest there was a general reduction in all metal concentrations in all soil samples. Tailings soil planted with L. camara (TLc) recorded the highest percentage metal reduction by Pb with 81.9%. Percentage reduction in metal concentrations was greater in tailing soil and in tailing amended with fertilizer planted with L. camara than those planted with C. odorata. Chromolaena odorata in tailing soil (TCo) recorded the highest metal accumulation for As with a ratio of 63.2. Results of the second harvest showed a maximum metal accumulation ratio of 49.0 for As in C. odorata growing in tailing soil amended with fertilizer (FTCo). In general accumulation of all metals by the two plants was found to be higher at the first harvest (one and half months) than at the second harvest (three months). The level of fertilizer application was not effective in enhancing metal uptake by both plant species. The species accumulation factors and bioaccumulation factors showed their specific metal affinity and time limitations for their application as phytoremediants. Both Chromolaena odorata and Lantana camara showed significant accumulation for Arsenic (As) and Iron (Fe). Lantana camara was a good candidate for hyperaccumulation of Copper (Cu) and Lead (Pb) whilst Chromolaena odorata was a good candidate for hyperaccumulation of Zinc (Zn) and Cadmium (Cd). In general accumulation in Latana camara was more effective and at optimum on short term cultivation whilst Chromolaena odorata was found to be a more effective phytoremediator on long term cultivation. The adaptability of these two indigenous plants species to heavy metal stress thus provides useful information for their selective exploitation in phytoremediation of contaminated mine sites.

Source: KNUST