Euclea Crispa Research Articles

Diet Mixing and Supplementation Present an Opportunity to Increase the Use of Encroaching Woody Plants by Goats.

Along with the woody plant expansion that is predicted to continue at the expense of the grassy layer is the increasing societal demand for animal protein and livestock products. Unless concerted efforts by land users, ecologists, and animal scientists are made to increase the utilization of trees and shrubs as forage, it will be impossible to meet future demand for meat and meat products. We conducted two short-term pen experiments to determine the effects of (1) supplementation with polyethylene glycol (PEG-a polymer purported to bind and neutralize the negative effects of tannins), a high-protein source (soybean meal), and a high-energy source (yellow maize grain) and (2) diet mixing (single-species vs. multispecies diets) on the intake of condensed tannin-rich woody plants (i.e., Searsia lancea, S. pyroides, and Euclea crispa) by goats. While all three forage species were used in the diet mixing experiment (Exp. 2), only E. crispa was used in the supplementation experiment (Exp. 1). Supplementing goats with energy- and protein-rich sources significantly increased the intake of E. crispa (p < 0.05), 713.4 g ± 13.5 and 760 g ± 28.9, respectively, whereas those on the control diet maintained their intake at 540.32 g ± 11.2. Although PEG tended to increase the consumption of E. crispa by goats, the observed increase was not significant (p > 0.05) from that observed in other treatments. In the diet mixing experiment, goats offered a combination of all three forage species attained substantially higher dry matter intakes compared to the goats offered these species individually (p < 0.05). While longer-term field experiments are needed in the African savannas, we postulate from the current results that management strategies that provide animals with (1) a variety of species in the diet vs. monocultures and (2) a combination of nutrient-rich and tannin-rich species may improve the ability of goats to consume chemically defended woody plants.

Retracted: (5E,7E)-4,5,6 Trihydroxy-3-(hydroxymethyl)tetrahydro-2H-pyran-2-ylheptadeca-5,7-dienoate from Euclea crispa (L.) Inhibits Ovarian Cancer Cell Growth by Controlling Apoptotic and Metastatic Signaling Mechanisms.

[This retracts the article DOI: 10.1155/2022/4464056.].

The deterrent effects of individual monoterpene odours on the dietary decisions of African elephants

African savanna elephants use pre-ingestive olfactory cues when making dietary choices, and previous research has observed that elephant diet choice is negatively correlated with vegetation species that contain high concentrations of monoterpenes. However, the frequency and concentration of monoterpenes can vary dramatically across plant species. Thus, we aimed to explore the effects that the odours of individual monoterpenes have on elephant diet choice and how these effects vary with concentration. To do this, we conducted three odour-based choice experiments focusing on eight common monoterpenes found in the woody plants in Southern African savannas. In the first experiment, we tested whether elephant diet choice for a frequently consumed plant (Euclea crispa) was influenced by the addition of the odour of an individual monoterpene at a set concentration. In the second experiment, we explored the relative deterrence of each monoterpene. Lastly, we tested how elephant diet choice varied as a function of the addition of individual monoterpene odours at 5%, 10%, and 20% concentrations. We found that the elephants avoided most individual monoterpenes at high concentrations, with the exception being α-pinene. Furthermore, we found that the odours of some individual monoterpenes were, in fact, more deterrent than others. In the third experiment, we found that the elephants avoided β-pinene, limonene, ocimene, γ-terpinene, and terpinolene across all concentrations, but only avoided sabinene and linalool at high concentrations. Ultimately, our results show that the odour of individual monoterpenes may deter elephant consumption, but that this deterrent effect depends on both the monoterpene and its concentration.

(5E,7E)-4,5,6 Trihydroxy-3-(hydroxymethyl)tetrahydro-2H-pyran-2-ylheptadeca-5,7-dienoate from Euclea crispa (L.) Inhibits Ovarian Cancer Cell Growth by Controlling Apoptotic and Metastatic Signaling Mechanisms.

Bioactive compound (5E,7E)-4,5,6 trihydroxy-3-(hydroxymethyl)tetrahydro-2H-pyran-2-ylheptadeca-5,7-dienoate (compound 2) was isolated from Euclea crispa (E. crispa) by the chromatographic methods. Further, the compound was confirmed by spectroscopic techniques such as ultraviolet-visible (UV/Vis) spectrometer, Fourier transform infrared (FTIR) spectrometer, and 1H and 13C nuclear magnetic resonance (NMR). Compound 2 exhibited a significant antioxidant activity with IC50 values. It restrained the auxesis of HO-8910 cells in a shot-dependent mode. CXCR4, HER2, and Akt proteins involved in cell proliferation and metastasis were found to be significantly reduced (p < 0.05). The protein that is responsible for the death of cells (Bcl-2 and Bcl-xL) was reduced (p < 0.05), while the protein expression of p53 and caspase-9 was increased (p < 0.05) in compound 2-treated HO-8910 cells. The results of molecular docking analysis showed the binding affinity with CXCR4 and HER2. Thus, compound 2 can serve as a promising chemotherapeutic agent for the intervention of ovarian cancer. The findings of this study conclude that compound 2 from E. crispa might work as a potential antioxidative and chemotherapeutic agent. The in vivo studies and attempts will pave way for this compound to be an effective drug hereafter.

Characterization of (2E,6E)-3,7,11-Trimethyldodeca-2,6,10-Trien-1-Ol with Antioxidant and Antimicrobial Potentials from &lt;i&gt;Euclea Crispa&lt;/i&gt; (Thunb.) Leaves

(2E,6E)-3,7,11-Trimethyldodeca-2,6,10-trien-1-ol or farnesol is a natural isoprenoid possessing a range of beneficial biological activities as anti-candidiasis, anti-tumor and anti-hyperglycaemia. The present study, for the first time, isolated and identified farnesol from Euclea crispa leaves’ extract, subsequently, validated its antioxidant and antimicrobial potentials. The isolated compound was confirmed by spectroscopic techniques including ultraviolet-visible (UV/Vis), fourier-transform infrared (FTIR), and 1H and 13C magnetic resonance (NMR) spectroscopies. By in vitro investigations, farnesol exhibited a considerable antioxidant activity with IC50 values of 113.79, 109.59, and 116.65 µg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and nitric oxide radical scavenging assays, respectively. Additionally, farnesol performed a potent reducing power capacity which was in line with ascorbic acid, an outstanding antioxidant. By the disc-diffusion assay, farnesol exposed the superior antimicrobial activity against various disease-causing microorganisms. Significantly, at the concentration of 50 µg/mL, the compound effectively inhibited the growth of Escherichia coli and Aspergillus niger with inhibition zones of 12 and 11 mm, respectively. Findings from this research suggest that E. crispa leaf is a potential source of farnesol, a powerful antioxidant and antimicrobial agent.

Characterization of (2E,6E)-3,7,11-Trimethyldodeca-2,6,10-Trien-1-Ol with Antioxidant and Antimicrobial Potentials from &lt;i&gt;Euclea Crispa&lt;/i&gt; (Thunb.) Leaves

(2E,6E)-3,7,11-Trimethyldodeca-2,6,10-trien-1-ol or farnesol is a natural isoprenoid possessing a range of beneficial biological activities as anti-candidiasis, anti-tumor and anti-hyperglycaemia. The present study, for the first time, isolated and identified farnesol from Euclea crispa leaves’ extract, subsequently, validated its antioxidant and antimicrobial potentials. The isolated compound was confirmed by spectroscopic techniques including ultraviolet-visible (UV/Vis), fourier-transform infrared (FTIR), and 1H and 13C magnetic resonance (NMR) spectroscopies. By in vitro investigations, farnesol exhibited a considerable antioxidant activity with IC50 values of 113.79, 109.59, and 116.65 µg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and nitric oxide radical scavenging assays, respectively. Additionally, farnesol performed a potent reducing power capacity which was in line with ascorbic acid, an outstanding antioxidant. By the disc-diffusion assay, farnesol exposed the superior antimicrobial activity against various disease-causing microorganisms. Significantly, at the concentration of 50 µg/mL, the compound effectively inhibited the growth of Escherichia coli and Aspergillus niger with inhibition zones of 12 and 11 mm, respectively. Findings from this research suggest that E. crispa leaf is a potential source of farnesol, a powerful antioxidant and antimicrobial agent.

Evaluations of biocidal potential of Euclea crispa stem bark extract and ability to compromise the integrity of microbial cell membrane

This study evaluates biocidal effect of Euclea crispa stem bark extract and determines time-kill kinetics of its potent fractions as well as membrane attack capability. Susceptibility of the bacterial cells and minimum inhibitory concentrations (MICs) were determined via agar-well diffusion and broth micro-dilution respectively, time-kill kinetics were evaluated at different concentrations over 2-h period and membrane attack potential was evaluated via scanning electron microscopy imaging and measurement of the amount of proteins and nucleic acids released from the cells. Maximum zone of inhibition (22 ± 0.58 mm) was observed for n-butanol and ethyl acetate fractions at 10 mg/ml. The lowest MIC exhibited by n-butanol (0.31 mg/ml) was against Enterococcus faecalis while that of ethyl acetate, n-hexane and aqueous fractions was 0.63 mg/ml against a number of test isolates. After 120 min of contact time at 1 × MIC, ethyl acetate fraction achieved total mortality against Listeria sp. and S. Typhimurium selected as representative isolates and when the concentration was increased to 2 × MIC n-butanol and aqueous fractions achieved total killing against Listeria sp. The SEM images revealed a level of anatomical disruption in the membrane of test isolates. Maximum amount of proteins released from Listeria sp. (0.63 ± 0.004 μg/ml) was by ethyl acetate fraction, while n-hexane fraction released maximum amount (0.79 ± 0.001 μg/ml) from S. Typhimurium under the same concentration of 3 × MIC after 120 min of exposure. The maximum amount of nucleic acids (47.9 ± 0.12 μg) released from Listeria sp. was by n-butanol fraction at 3 × MIC after 120 min, hence, membrane disruption is confirmed as one of the mechanisms behind the biocidal action of E. crispa extracts.

Antioxidant and antimicrobial activities of (6E, 10E)-2, 6, 24-trimethyl pentacosa-2, 6, 10-triene from Euclea crispa leaves

The purpose of the present study attempt to investigate the antioxidant and antimicrobial activities of isolated bioactive compound from ethanolic extract of Euclea crispa (E. crispa) leaves. Column chromatography method was used to isolate the bioactive compound from the plant leaves followed by UV-Spectroscopy. FT-IR, 1H and 13C NMR analyses were used to identify the structure of the isolated compound. Subsequently, the antioxidant activity was demonstrated by 2, 2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay, reducing power assay, ferric reducing antioxidant power (FRAP) assay, hydroxyl scavenging assay and nitric oxide scavenging assay while disc-diffusion assay was used to analyze the antimicrobial activity. The NMR and other spectral data confirmed that the isolated compound was (6E, 10E)-2, 6, 24-trimethylpentacosa-2, 6, 10-triene (compound-1). The DPPH radical scavenging (116.1 ± 0.9 μg/ml), hydroxyl scavenging (118.9 ± 1.0 μg/ml) and nitric oxide scavenging (124.3 ± 0.2 μg/ml) showed the significant half maximal inhibitory concentration (IC50) values on compound-1 suggesting good antioxidative potential. Additionally, it exhibited considerable activity in reducing power and FRAP (the maximum absorption of 0.41 ± 0.02 and 0.54 ± 0.02 at 500 μg/ml, respectively) when compared with standard drug. Furthermore, compound-1 showed maximum antimicrobial activity with inhibition zone against the tested microorganism of Staphylococcus aureus, Streptococcus aureus, Escherichia coli, Klebsiella pneumonia, Aspergillus niger and Aspergillus terreus. Conclusively, the isolated bioactive compound-1 from E. crispa leaves could be a new source of natural antioxidative and antimicrobial agents with potential value.

ANTI-PROLIFERATIVE AND ANTIOXIDANT ACTIVITY OF FOUR INDIGENOUS SOUTH AFRICAN PLANTS.

Background: Cancer is a major cause of death worldwide. Limitations of current cancer therapies necessitate the search for new anticancer drugs. Plants represent an immeasurable source of bioactive compounds for drug discovery. The objective of this study was to assess the anti-proliferative and antioxidant potential of four indigenous South African plants commonly used in traditional medicine. Materials and Methods: The anti-proliferative activity of the plant extracts were assessed by the 2,3-Bis-(2-Methoxy-4- Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide (XTT) assay on A431; HaCat; HeLa; MCF-7 and UCT-Mel 1 cells and sulforhodamine-B (SRB) assay on HCT-116 and HCT-15 cell lines. Antioxidant activity was determined using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO) and superoxide scavenging assays. Results: Three of the plant extracts (Combretum mollefruit, Euclea crispa subsp. crispa leaves and stems and Sideroxylon inerme leaves and stems showed anti-proliferative activity on the A431 cells with IC50values ranging between 26.9 - 46.7 μg/ml. The Euclea crispa subsp. crispa extract also showed anti-proliferative activity on the MCF-7 cell line (45.7 μg/ml). All of the plant extracts (Combretum molle leaves and fruit, Euclea crispa subsp. crispa leaves and stems, Sideroxylon inerme leaves and stems and Terminalia prunioides leaves and stems) showed DPPH scavenging activity with IC50 values ranging from 1.8 μg/ml to 11.5 μg/ml. Conclusion: These results indicate that the active extracts of Combretum molle, Euclea crispa subsp. Crispa and Sideroxylon inerme warrants further investigation to determine the mechanism of anti-proliferative activity against cancerous cells. These plant extracts also show potential for further evaluation in the prevention and treatment of cancer.

Screening of Potential Phytocompounds From Euclea crispa (Thunb.) Leaves Targeting Human Epidermal Growth Factor Receptor 2 (HER2) Signaling Pathway.

ABSTRACTBackground:Overexpression of human epidermal growth factor receptor 2 (HER2) plays an important role in the development and progression in a variety of cancers and it is a novel therapeutic target for breast cancer and ovarian cancer. Euclea crispa (E. crispa) is a South African medicinal plant in the family Ebenaceae used in the management of different human diseases and disorders.Aims:The aim of this study was to evaluate the potential inhibitors against HER2 from hexane extract of E. crispa leaves.Materials and Methods:Chemical fingerprinting method was used to identify the presence of natural compounds from the extract whereas their inhibitory activities were analyzed by molecular docking analysis against HER2. Absorption, distribution, metabolism, and excretion (ADME) properties also predicted to establish the pharmacokinetics and pharmacodynamics profiles of the selected compounds.Results:The molecular docking analysis expressed that phenyl glucuronide, hydrocortisone acetate, and 6-(4,6-dioxo-1,4,5,6-tetrahydropyrimidin-2-yl-amino)hexanoic acid trifluoroacetate possess good inhibitory activities with good glide score of −6.63, −5.41, and −5.40 and glide energy of −35.03, −42.51, and −31.38 kcal/mol, respectively when compared with standard Food and Drug Administration–approved drug and other compounds. All the screened compounds were within the acceptable and permissible limits of ADME properties.Conclusion:Thus, from this study it can be concluded that, these screened natural compounds from E. crispa leaves may serve as potential inhibitors for HER2 and they might lead to development of new therapeutic agents against cancer and its associated complications.

EUCLEA CRISPA: REVIEW OF ITS BOTANY, ETHNOMEDICINAL USES, AND PHARMACOLOGICAL PROPERTIES

Euclea crispa is widely used as herbal medicine in southern Africa. This study was aimed at reviewing the botany, ethnomedicinal uses, and validated pharmacological properties of E. crispa. The literature search for information on ethnomedicinal uses and pharmacological activities of E. crispa was undertaken using databases such as web of science, BMC, science direct, elsevier, scopus, PubMed, and scielo. Other relevant literature sources included books, book chapters, websites, theses, conference papers, and other scientific publications. The extensive literature survey revealed that the bark, fruits, leaves, and roots of E. crispa are commonly used as herbal medicines for wounds, constipation, cough, stomach disorders, epilepsy, rheumatism, and diabetes. Pharmacological studies on E. crispa indicate that the species has amyloid β-peptide lowering effects, antibacterial, antidiarrheal, antifungal, and cell membrane disruption activities. E. crispa should be subjected to further scientific evaluations aimed at elucidating its chemical, pharmacological, and toxicological properties. Such detailed research should also include experimental animal studies, randomized clinical trials, and target-organ toxicity studies involving E. crispa extracts and its derivatives.

&lt;i&gt;In vitro&lt;/i&gt; Assessment of &lt;i&gt;Euclea crispa&lt;/i&gt; (Thunb.) Leaf Extracts against &lt;i&gt;Campylobacter&lt;/i&gt; spp. and &lt;i&gt;Escherichia coli&lt;/i&gt; - Common Diarrhoeal Agents

Diarrhoea is a common childhood disease with high mortality rate. This study thus aimed at assessing effect of Euclea crispa leaf extract and its fractions against diarrhoea causing bacterial isolates and determining time-kill dynamics by each of the potent fractions. Susceptibility of each isolates was determined by agar well diffusion while the minimum bacteriostatic and bactericidal concentrations were determined by agar dilution method. Time-Kill dynamics was evaluated over a period of 120 min against Escherichia coli (1323) representing Gram negative isolates. The zones of inhibition exhibited by the leaf extract at 20 mg/ml range between 17±0.28 and 22±0.00 mm while that of the partitioned fractions at 10 mg/ml are between 14±0.00 and 22±0.00 mm. MICs of the leaf extract range between 0.31 and 2.50 mg/ml. The lowest MIC (0.08 mg/ml) is exhibited by the fractions partitioned into ethyl acetate, n-butanol and water while that of n-hexane and chloroform is 0.16 mg/ml. The lowest MBC exhibited by all the fractions is 0.31 mg/ml except that of the chloroform (1.25 mg/ml). Total mortality was achieved by the ethyl acetate fraction at a concentration of 2 × MIC after 120 min of contact time, meanwhile the mortality rate achieved by n-butanol, n-hexane, aqueous and chloroform fractions were 98, 94.6, 91.8 and 83.7% respectively under similar condition. This study showcase significant antidiarrhoeal potential of Euclea crispa leaf extracts and equally indicates a source of readily available therapeutic agent against diarrhoeal infection in South Africa and environs.

Significance of combination therapy between Euclea crispa (Thunb.) (leaf and stem bark) extracts and standard antibiotics against drug resistant bacteria

This study evaluates the probable effect of combination therapy between the extracts of Euclea crispa and standard antibiotics against selected resistant strains of bacterial isolates. The crude extracts were partitioned using a solvent partitioning system. The isolates were screened via determination of minimum inhibitory concentrations (MICs) using broth micro-dilution method and the combination assessment was carried out via time-kill assay to determine the probable synergisms. The MICs by the plant extracts range from 310 to 630 μg/ml (leaf extract) and from 630 to 1250 μg/ml (stem bark extract). The MICs by erythromycin and chloramphenicol range between 31 and 250 μg/ml, while that of ampicillin is between 63 and 500 μg/ml. The range exhibited by streptomycin and tetracycline is between 8 and 250 μg/ml and 6 and 100 μg/ml respectively. Out of 130 different combination tests between the leaf extract and antibiotics, 91.5% express synergy while 8.5% are indifferent. On the other hand, 88.5% of the same number of combination tests show synergism between the stem bark extract and standard antibiotics with no record of antagonism in both cases. The leaf and stem bark extracts of E. crispa have been confirmed, in the course of this study, to possess some bioactive principles which may serve to enhance potency of the available antibiotics against multidrug resistant organisms. Thus, it indicates a source of alternative therapy in combating infectious diseases.

Analysis of Novel C-X-C Chemokine Receptor Type 4 (CXCR4) Inhibitors from Hexane Extract of Euclea crispa (Thunb.) Leaves by Chemical Fingerprint Identification and Molecular Docking Analysis

: Objectives: To evaluate the potential inhibitors aginst CXCR4 from hexane extract of Euclea crispa (E. crispa) leaves. Methods: The natural compounds were identified and charecterized through GC-MS analysis. Molecular docking studies carried out to investigatethe inhibitory activity Angainst CXCR4. Absorption, Distribution, Metabolism, and Excretion (ADME) properties also were predicted to find pharmacokinetics and pharmacodynamics of compounds. Results: The molecular docking simulations revealed that, Benzoic acid 3-methyl-4-(1,3,3,3-tetrafluoro-2-methoxycarbonyl-propenylsulfanyl)- phenyl ester (SCHEMBL15979821), Hydrocortisone Acetate and Phenyl Glucuronide possess good inhibitory activites (Glide Score of -7.06, -6.97, -6.47 and Glide Energy of -43.22, -48.27 and -32.80 kcal/mol respectively) when compared with standard FDA approved drug and other compounds. All the screened compounds were within the acceptable and permissible limits of ADME properties. Conclusion: Thus, from this study it can be concluded that, these screened natural compounds from E. crispa leaves may serve as potential inhibitors for CXCR4 and they might lead to development of new therapeutic agents against cancer and its associated complications.Key words: E.crispa, GC-MS analysis, CXCR4, Molecular docking, ADME properties.

In vitro antioxidant potential of Euclea crispa (Thunb.) leaf extracts

Background: Euclea crispa is a South African medicinal plant belonging to the family Ebenaceae. Objectives: The objective of this study was to analyze the in vitro antioxidant activity of different extracts of E. crispa leaves. Materials and Methods: 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, reducing power assay, ferric reducing antioxidant power (FRAP) assay, hydroxyl scavenging assay, and nitric oxide scavenging assay were used to analyze free-radical scavenging activity. The superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), total reduced glutathione (TRG), and estimation of vitamin C assays were carried out to analyze the enzymatic and nonenzymatic antioxidants on a fresh leaf of E. crispa. Results: The DPPH radical scavenging assay (135.4 ± 0.7 μg/ml), hydroxyl scavenging assay (183.6 ± 0.9 μg/ml), and nitric oxide scavenging assay (146.2 ± 1.3 μg/ml) showed the significant half maximal inhibitory concentration (IC50) values in ethanolic extract when compared to the ethyl acetate, chloroform, and petroleum ether extract of E. crispa leaves. Further, the ethanolic extract exhibited good reducing power assay and FRAP assay showed (the maximum absorption of 0.79 and 0.68 at 500 μg/ml, respectively) when compared to other solvent extracts. The fresh E. crispa leaves possess high content of enzymatic and nonenzymatic antioxidants such as SOD (41.3 ± 0.34 units/mg protein), CAT (124 ± 0.54 μmole of H2O2consumed/min/mg protein), GPX (261.2 ± 0.42 μg of glutathione oxidized/min/mg protein), TRG (42.3 ± 0.16 μg/mg protein), and estimation of vitamin C (185 ± 0.39 μg/mg) assays. Conclusion: Based on the results obtained from this study, it can be concluded that the E. crispa leaves can be used for the preparation of antioxidative therapeutic agents. However, further studies are necessary to substantiate the current findings. Abbreviations Used: DPPH: 2, 2-diphenyl-1-picrylhydrazyl, FRAP: Ferric reducing antioxidant power, SOD - Superoxide dismutase, CAT: Catalase, GPX: Glutathione peroxidase, TRG: Total reduced glutathione, ROS: Reactive oxygen species, DNA: Deoxyribonucleic acid, EDTA: Ethylenediaminetetraacetic acid, TCA: Trichloroacetic acid, TBA: Thiobarbituric acid, NED: Naphthyl ethylenediamine dihydrochloride, IC50: Half maximal inhibitory concentration.

Time-kill kinetics and biocidal effect of Euclea crispa leaf extracts against microbial membrane.

To evaluate antimicrobial potential of the fractions partitioned from Euclea crispa leaf extract and determination of their impact on cell membrane disruption. Antimicrobial potentials were evaluated via susceptibility test, determination of minimum inhibitory concentrations (MICs) and time-kill kinetics of the potent fractions. Degree of membrane disruption was determined by the amount of proteins and nucleotides released from within the cells and SEM images of the membrane after 120min of treatment. The largest inhibition zone (25.5±0.50mm) was obtained by ethylacetate fraction against Aeromonas hydrophilla at 10mg/mL. The lowest MIC (0.16mg/mL) was exhibited by n-butanol and ethylacetate fractions against test bacteria while all fractions exhibited MIC values between 0.31 and 1.25mg/mL against susceptible yeast. n-Butanol fraction achieved absolute mortality against Bacillus pumulis (B.pumulis) and Klebsiella pneumoniae (K.pneumoniae) after 90 and 120min contact time respectively at 1×MIC. Total mortality also achieved by n-hexane fraction against B.pumulis and K.pneumoniae after 90 and 120min respectively at 2×MIC. Ethylacetate fraction achieved absolute mortality against both bacteria after 120min at 2×MIC. n-Hexane fraction achieved total mortality against Candida albicans after 120min at 1×MIC. Maximum amount of proteins (0.566μg/mL) was released from K.pneumoniae by n-butanol fraction at 2×MIC after 120min of treatment while the maximum amount of nucleotides released (4.575μg) was from B.pumulis by n-hexane fraction under similar condition. This study suggests the leaf of Euclea crispa a source of bioactive compound with membrane attack as one of the mechanisms of its biocidal action.

Assessment of antidiarrhoea properties of Euclea crispa (Thunb.) leaf extract and fractions

Assessment of antidiarrhoea properties of Euclea crispa (Thunb.) leaf extract and fractions

Seasonal variations in diet selection of Nguni goats: effects of physical and chemical traits of browse

Goats select some browse species more than others, given options. Seasonal trends of diet selection of Nguni goats indexed by intake were investigated in cafeteria-style experiments. The relationships between diet selection and plant chemical/physical traits of Vachellia nilotica, Vachellia robusta, Dichrostachys cinerea, Euclea crispa, Rhus lancea and Ziziphus mucronata, representing abundant species were studied in the dry and rainy seasons. Seasonal changes in browses affected diet selection. Selection of long shoot species, which were concomitantly broad-leafed, was higher than species with short shoots. Selection was higher for spineless than spinescent species. Diet selection correlated positively with increased leaf mass. In the rainy season, cellulose positively correlated with intake, number of bites and browsing time, whereas in the dry season, cellulose correlated with bite size. Diet selection tended to be driven more by shoot morphology and leaf mass than by either spinescence or plant chemistry. Plant chemical influence on diet selection was diverse in both seasons and showed no definite trend, whereas spinescence had no significant effect on short-term intake. The results represent important input to goat production and range forage species management.

Ethnobotanical survey of medicinal plants used by Bapedi traditional healers to manage HIV/AIDS in the Limpopo Province, South Africa

During the first half of 2012, a semi-structured questionnaire was employed to conduct a survey on medicinal plants used by Bapedi traditional healers in their human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) management protocol. A total of 26 plant species were used by these healers to treat HIV/AIDS. Majority (96.1%) of the species used were indigenous and only 3.9% were exotic. Most (88.4%) of the indigenous species appear on South African National Red Data List of Plants. Burkea africana, Citrullus lanatus, Cinnamomum verum, Euclea crispa, Elephantorrhiza elephantina, Euphorbia maleolens, Geigeria aspera, Plectranthus ciliatus, Sarcostemmaviminale, Zanthoxylum capense and Zanthoxylum humile are recorded for the first time as a treatment for HIV/AIDS. The most used species by Bapedi healers to treat this pandemic was E. maleolens (11.7%) and E. elephantina (8.8%). Roots (66.6%) from 26 species were mostly used to prepare remedies. Twelve (60%) multi extract and eight (40%) single extract preparations were recorded. Extracts were mostly (99%) prescribed orally. The disappearance or improvement of symptoms was considered as indicators of a successful treatment. The present study concludes that Bapedi traditional healers’ knowledge can lead to useful medicinal plants to manage and treat HIV/AIDS infections. Key words: Bapedi traditional healers, human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), Limpopo Province, medicinal plants.

Rapid Identification of Bioactive Compounds Reducing the Production of Amyloid β-Peptide (Aβ) from South African Plants Using an Automated HPLC/SPE/HPLC Coupling System

Automated HPLC/SPE/HPLC coupling experiments using the Sepbox system allowed the rapid identification of four bioactive principles reducing the production of amyloid <TEX>$\beta$</TEX>-peptide (<TEX>$A{\beta}$</TEX>) from two South African plants, Euclea crispa subsp. crispa and Crinum macowanii. The structures of biologically active compounds isolated from the methanol extract of Euclea crispa subsp. crispa were assigned as 3-oxo-oleanolic acid (1) and natalenone (2) based on their NMR and MS data, while lycorine (3) and hamayne (4) were isolated from the dichloromethane-methanol (1:1) extract of Crinum macowanii. These compounds were shown to inhibit the production of <TEX>$A{\beta}$</TEX> from HeLa cells stably expressing Swedish mutant form of amyloid precursor protein (APPsw).