South African Medicinal Plants Research Articles

Bioactivity of selected South African medicinal plants used for the treatment of sexually transmitted diseases

Bioactivity of selected South African medicinal plants used for the treatment of sexually transmitted diseases

Rapid propagation of Mondia whitei by embryonic cell suspension culture in vitro

We have developed an efficient in vitro mass propagation system for Mondia whitei, an endangered South African medicinal plant of significant traditional importance, using somatic embryogenesis in cell suspension culture. Leaf explants generated friable embryogenic calli (FEC) when cultured on embryogenic callus induction medium (ECIM), which contained Murashige and Skoog (MS) medium, 8gL−1 agar with 30–50gL−1 sucrose and different plant growth regulators [PGRs: 2,4-dichlorophenoxyacetic acid (2,4-D) and picloram]. Different stages (globular/heart/torpedo/cotyledonary) of somatic embryos (SEs) were produced from FEC using liquid MS medium supplemented with different concentrations and combinations of PGRs. Formation of SEs (torpedo and cotyledonary stages) were significantly higher in liquid MS medium containing 0.5μM naphthaleneacetic acid (NAA) and 1μM meta-topolin riboside (mTR). The highest embryo germination rates achieved in liquid (half-strength MS+0.5μM NAA) and solid (MS+40gL−1 sucrose +2μM NAA) media were 98.3% and 97.6%, respectively. The synthetic seeds were prepared with sodium alginate (3% w/v) and calcium chloride (100mM) from SEs (torpedo and cotyledonary stages) and stored in darkness at 25±2°C and 4°C for 10–60days. Germination frequency was 68.6% at 25±2°C after 60days of storage. All the plantlets from SEs and synthetic seeds were successfully acclimatized (100%) with vermiculite in the greenhouse. These results provide high-frequency, rapid production and germination of SEs and synthetic seeds, and provides further strategies that can be used for overcoming extinction threats, ensuring germplasm conservation, production of bioactive compounds, evaluation of bioactivity and genetic transformation studies.

Inhibition of protein glycation, antioxidant and antiproliferative activities of Carpobrotus edulis extracts

Carpobrotus edulis is an important South African medicinal plants used as a food and therapeutic agent in traditional medicine. The aim of this study was to determine the phytochemical content, antioxidant, antiglycation and cytotoxic effect against Human Colon Cancer Cell Line (HCT-116) of aqueous and ethanol-water (1:1v/v) extracts of Carpobrotus edulis.The content of total phenolics and flavonoids in aqueous and ethanol-water extract were 151.99μg and 66.35μg gallic acid equivalents/mg of dry extract, and 38.84μg and 21.96μg quercetin/mg of dry extract, respectively. Furthermore, phenolic compositions analysis indicated the presence of seven majority compounds including sinapic acid, ferulic acid, luteolin7-o-glucoside, hyperoside, isoquercitrin, ellagic acid and isorhamnetin 3-O-rutinoside. The ethanol-water extract (100-1000μg/mL) showed better antioxidant activity than aqueous extract. Furthermore, Carpobrotus edulis extracts, especially ethanol-water extract significantly inhibited the formation of fluorescent advanced glycation end products, prevented oxidation-induced protein damage and exhibited a cytotoxic effect against HCT116 cells, with a significant decrease in cell viability after 24h of incubation. The results obtained suggest that the Carpobrotus edulis extracts could be used as an easily accessible source of natural antioxidants and as potential phytochemicals against protein glycation and colon cancer.

The anti-arthritic, anti-inflammatory, antioxidant activity and relationships with total phenolics and total flavonoids of nine South African plants used traditionally to treat arthritis.

BackgroundOxidative stress predisposes the human and animal body to diseases like cancer, diabetes, arthritis, rheumatoid arthritis, atherosclerosis and chronic inflammatory disorders. Hence, this study seeks to determine the antioxidant, anti-inflammatory and anti-arthritic activities of acetone leaf extracts of nine South African medicinal plants that have been used traditionally to treat arthritis and inflammation.MethodsThe anti-inflammatory activity of the extracts was determined by investigating inhibition of nitric oxide production in lipopolysaccharide activated RAW 264.7 macrophages as well as 15-lipoxygenase enzyme inhibition. An anti-protein denaturation assay was used to determine the anti-arthritic properties of the extracts. The antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethyl-benzthiazoline-6-sulfonic acid) (ABTS) radical scavenging assays and ferric reducing antioxidant power (FRAP). The total phenolic and total flavonoid concentration of extracts were determined by using standard methods.ResultsAll extracts inhibited nitric oxide production in a dose-dependent manner in the LPS-stimulated RAW 264.7 macrophages. Extracts of Maesa lanceolata and Heteromorpha arborescens inhibited NO production by 99.16 % and 89.48 % at a concentration of 30 μg/ml respectively. Elaeodendron croceum and Calpurnia aurea extracts had strong activity against 15-lipoxygenase activity with IC50 values of 26.23 and 34.70 μg/ml respectively. Morus mesozygia and Heteromorpha arborescens extracts had good in vitro anti-arthritic activity with IC50 values of 11.89 and 53.78 μg/ml, the positive control diclofenac sodium had IC50 value of 32.37 μg/ml. The free radical scavenging activity of the extracts in DPPH assays ranged between 7.72 and 154.77 μg/ml. Trolox equivalent antioxidant capacity (TEAC) and FRAP values ranged from 0.06 to 1.32 and 0.06 to 0.99 respectively.ConclusionsResults from this study support the traditional use of the selected medicinal plants in the management of arthritis and other inflammatory conditions. The free radical scavenging capacity of the extracts may be related to an immune boosting potential.

Cytotoxicity of South-African medicinal plants towards sensitive and multidrug-resistant cancer cells

Ethnopharmacological relevanceTraditional medicine plays a major role for primary health care worldwide. Cancer belongs to the leading disease burden in industrialized and developing countries. Successful cancer therapy is hampered by the development of resistance towards established anticancer drugs. AimIn the present study, we investigated the cytotoxicity of 29 extracts from 26 medicinal plants of South-Africa against leukemia cell lines, most of which are used traditionally to treat cancer and related symptoms. Material and methodsWe have investigated the plant extracts for their cytotoxic activity towards drug-sensitive parental CCRF-CEM leukemia cells and their multidrug-resistant P-glycoprotein-overexpressing subline, CEM/ADR5000 by means of the resazurin assay. A panel of 60 NCI tumor cell lines have been investigated for correlations between selected phytochemicals from medicinal plants and the expression of resistance-conferring genes (ABC-transporters, oncogenes, tumor suppressor genes). ResultsSeven extracts inhibited both cell lines (Acokanthera oppositifolia, Hypoestes aristata, Laurus nobilis, Leonotis leonurus, Plectranthus barbatus, Plectranthus ciliates, Salvia apiana). CEM/ADR5000 cells exhibited a low degree of cross-resistance (3.35-fold) towards the L. leonurus extract, while no cross-resistance was observed to other plant extracts, although CEM/ADR5000 cells were highly resistant to clinically established drugs. The log10IC50 values for two out of 14 selected phytochemicals from these plants (acovenoside A and ouabain) of 60 tumor cell lines were correlated to the expression of ABC-transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS) and tumor suppressors (TP53). Sensitivity or resistance of the cell lines were not statistically associated with the expression of these genes, indicating that multidrug-resistant, refractory tumors expressing these genes may still respond to acovenoside A and ouabain. ConclusionThe bioactivity of South African medicinal plants may represent a basis for the development of strategies to treat multidrug-resistant tumors either by phytotherapeutic approaches with whole plant preparations or by classical drug development with isolated compounds such as acovenoside A or ouabain.

In vitro inhibition of Plasmodium falciparum early and late stage gametocyte viability by extracts from eight traditionally used South African plant species

Ethnopharmacological relevance:Extracts of plant species, used traditionally to treat malaria, have been extensively investigated for their activity against Plasmodium intraerythrocytic asexual parasites in search of new antimalarial drugs. However, less effort has been directed towards examining their efficacy in blocking transmission. Here, we report the results of the in vitro screening of extracts from eight selected plant species used traditionally to treat malaria in South Africa for activity against Plasmodium falciparum NF54 early and late stage gametocytes. The species used were Khaya anthotheca, Trichilia emetica, Turraea floribunda, Leonotis leonurus, Leonotis leonurus ex Hort, Olea europaea subsp. Africana, Catha edulis and Artemisia afra. Aim of the studyTo investigate the activities of extracts from plant species traditionally used for malaria treatment against P. falciparum gametocytes. Material and methods:Air-dried and ground plant leaves were extracted using acetone. Primary two point in vitro phenotypic screens against both early and late stage gametocytes were done at 10 and 20µg/ml followed by full IC50 determination of the most active extracts. Inhibition of gametocyte viability in vitro was assessed using the parasite lactate dehydrogenase (pLDH) assay. Results:Of the eight crude acetone extracts from plant species screened in vitro, four had good activity with over 50–70% inhibition of early and late stage gametocytes’ viability at 10 and 20µg/ml, respectively. Artemisia afra (Asteraceae), Trichilia emetica (Meliaceae) and Turraea floribunda (Meliaceae) were additionally highly active against both gametocyte stages with IC50 values of less than 10µg/ml while Leonotis leonurus ex Hort (Lamiaceae) was moderately active (IC50<20µg/ml). The activity of these three highly active plant species was significantly more pronounced on late stage gametocytes compared to early stages. Conclusion:This study shows the potential transmission blocking activity of extracts from selected South African medicinal plants and substantiates their traditional use in malaria control that broadly encompasses prevention, treatment and transmission blocking. Further studies are needed to isolate and identify the active principles from the crude extracts of A. afra, T. emetica and T. floribunda, as well as to examine their efficacy towards blocking parasite transmission to mosquitoes.

THREATENED MEDICINAL PLANTS OF SOUTH AFRICA: CASE OF THE FAMILY HYACINTHACEAE

Background: Traditional medicine plays a major role in the primary health care of many people living in rural areas. South Africa is a&#x0D; home to over 30,000 species of higher plants and 3,000 of these species have been found to be used in traditional medicine across the&#x0D; country. South African medicinal plants are decreasing at an alarming rate as a result of over exploitation. Today many medicinal plants&#x0D; face extinction but detailed information is lacking. The purpose of this paper was to review current and proposed cultivation strategies&#x0D; that could be used to improve plant conservation statuses, livelihoods of the people involved in medicinal plant industry and&#x0D; sustainability of this industry.&#x0D; Methods: In this review, emphasis was on the members of Hyacinthaceae family and the species Siphonochilus aethiopicus (Schweinf)&#x0D; B.L. Burtt (Zingiberaceae), which are some of the most traded and used in traditional herbal medicine. Detailed literature search was&#x0D; conducted on the current strategies that are being used for the cultivation of medicinal and food crops and a conceptual analysis of how&#x0D; technologies used for the cultivation of non-medicinal crops could be adopted for cultivation of medicinal plants in Africa. Siphonochilus&#x0D; aethiopicus was used as a case study to demonstrate the potential of using alternative cultivation strategy such as hydroponics in the&#x0D; cultivation of medicinal plants.&#x0D; Results: The results showed that hydroponics has the potential to improve plant growth. In conclusion, evidences suggest that there is&#x0D; potential for growth in the medicinal plant industry if optimum cultivation technologies such as hydroponics are implemented despite the&#x0D; perception that Africans have an ingrained traditional preference of wild harvested plants, on the contrary many Africans have no issues&#x0D; with cultivated medicinal plants.

Antibacterial screening and the isolation of bioactive compounds from seven South African medicinal plants

Antibacterial screening and the isolation of bioactive compounds from seven South African medicinal plants

Protective effect of South African indigenous medicinal plants against aflatoxin B1 induced mutagenicity

Protective effect of South African indigenous medicinal plants against aflatoxin B1 induced mutagenicity

Cytotoxicity, antimicrobial and anti-inflammatory properties of South African medicinal plants used to treat sexually transmitted and related opportunistic infections

Cytotoxicity, antimicrobial and anti-inflammatory properties of South African medicinal plants used to treat sexually transmitted and related opportunistic infections

Alternatives to improve long-term cultures of Harpagophytum procumbens in vitro

Aspects for long-term culture and maintenance of an important South African medicinal plant cultured in vitro are discussed. The organogenic potential of Harpagophytum procumbens callus culture was investigated. Callus-derived shoots were highly vitrified and of insufficient viability after their immediate development. Subcultivation of shoots, separated from the callus, improved their vitality and resilience. Addition of silicon diminished shoot-tip necrosis, improved growth of leaves and shoots, and the solidity of roots at their bases. Appropriate rotation of culture media enabled a successful long-term culture of this plant in vitro.

The efficacy and safety of nine South African medicinal plants in controlling Bacillus anthracis Sterne vaccine strain.

BackgroundAnthrax is a zoonotic disease caused by Bacillus anthracis, a Gram-positive spore-forming bacterium. The presence of the bacteria and the toxins in the blood of infected hosts trigger a cascade of pathological events leading to death. Nine medicinal plants with good activities against other bacteria were selected to determine their in vitro antibacterial activity against Bacillus anthracis Sterne strain. The cytotoxicity of the extracts on Vero kidney cells was also determined.ResultsThe minimum inhibitory concentration (MIC) values of the extracts against Bacillus anthracis Sterne strain ranged from 0.02 to 0.31 mg/ml. Excellent MIC values were observed for the following plant species: Maesa lanceolata (0.02 mg/ml), Bolusanthus speciosus, Hypericum roeperianum, Morus mesozygia (0.04 mg/ml) and Pittosporum viridiflorum (0.08 mg/ml). The total antibacterial activity of the extracts ranged from 92 to 5562 ml/g. Total activity presents the volume to which the extract from 1 g of plant material can be diluted and still inhibit microbial growth. Maesa lanceolata and Hypericum roeperianum had the highest total activity with values of 5562 and 2999 ml/g respectively. The extracts of Calpurnia aurea had the lowest total activity (92 ml/g). The cytotoxicity determined on Vero cells indicated that most of the extracts were relatively non-toxic compared to doxorubicin (LC50 8.3 ± 1.76 μg/ml), except for the extracts of Maesa lanceolata, Elaeodendron croceum and Calpurnia aurea with LC50 values at 2.38 ± 0.25, 5.20 ± 0.24 and 13 ± 2.26 μg/ml respectively. The selectivity index (SI) ranged from 0.02 to 1.66. Hypericum roeperianum had the best selectivity index, (SI = 1.66) and Elaeodendron croceum had lowest value (SI = 0.02).ConclusionsThe crude acetone extracts of the selected plant species had promising antibacterial activity against Bacillus anthracis. Maesa lanceolata extracts could be useful as a disinfectant and Hypericum roeperianum could be useful to protect animals based on its high total activity and selectivity index. Further investigation of these plant extracts may lead to the development of new therapeutic agents to protect humans or animals against anthrax.

The antimicrobial and antioxidant potential of Lithops lesliei, a South African medicinal plant

The antimicrobial and antioxidant potential of Lithops lesliei, a South African medicinal plant

Phenylpropanoid metabolism and pharmacology of the blood lily, Scadoxus puniceus, a highly traded South African medicinal plant

The current study utilised ultra-high performance liquid chromatography coupled with electrospray ionisation tandem mass spectrometry (UHPLC-MS/MS) to quantify the phenolic compounds in different organs of Scadoxus puniceus (Amaryllidaceae), an important South African medicinal plant. The antioxidant, antimicrobial and acetylcholinesterase (AChE) inhibitory activities of this species were also evaluated. UHPLC-MS/MS revealed a greater profusion of hydroxycinnamic acids (HCAs), accounting for 69.5% of the total phenolic acids as opposed to hydroxybenzoic acids (HBAs). Chlorogenic acid (CGA; 3-caffeoyl-D-quinic acid) was highly abundant (49.6% of HCAs) in the aerial organs suggesting a functional role of the compound against herbivory from the Amaryllis leaf borer which infested many of the stock plants. In addition to CGA, the current study is the first to report the presence of sinapic, gallic and m-hydroxybenzoic acids in the Amaryllidaceae. The accumulation of CGA in the leaves of S. puniceus substantiated the fact that leaf extracts exhibit significantly improved antioxidant activity (DPPH IC50 = 0.07 mg/mL) as compared to the bulb. CGA, a known antifungal agent conferred potent antifungal activity (minimum inhibitory concentration; MIC < 0.10 mg/mL) of leaf extracts against Candida albicans. Furthermore, ethanolic extracts of different organs of S. puniceus revealed AChE inhibitory activity in excess of 90% (IC50 = 0.07 – 0.15 mg/mL), with no significant difference between bulb and leaf extracts.

Abstract 5552: Medicinal plants show anticancer splicing activity of apoptotic genes

Abstract Oncogenesis is associated with splicing switches and a disruption of splicing regulation being specific for cancer formation and tumour progression. An association between differential expression of splicing isoforms and tumour progression has been shown for several proteins, such as MDM2 and survivin. Currently the analysis of cancer-specific alternative splicing is a promising step forward in basic and translational molecular biology. Traditional medicine has a long history and is still the major source of medicine in developing countries. Approximately 70% of the South African population consults traditional healers, perpetuating the need for scientific appraisal of traditional medicine as a means to establish its efficiency and safety Also, pharmacological and phytochemical insights into several plants have led to the discovery of novel chemicals and therefore novel drugs. Alternatively, such novel chemical structures can serve as lead compounds/templates for the design of new drugs. The aim was to ascertain if the South African medicinal plants have anticancer splicing activity. 10c cells were treated with Tulbhaghia violacea and Cotyledon orbiculata, followed by mRNA extraction and RT-PCR. The results showed that Tulbhaghia violacea and Cotyledon orbiculata extracts have anti-cancer splicing activity on the BCLX and the AXL apoptosis genes. Additionally Cotyledon orbiculata extract has an anticancer splicing activity of the angiogenesis gene VEGF165. VEGF Elisa also confirmed the VEGF165 VEGF165b splicing switch. We have shown that South African medicinal plants have anti-cancer splicing activity. The anti-cancer splicing activity of the VEGF gene by Cotyledon orbiculata could mean that this extract has both angiostatic and apoptotic anti-cancer activities. We are continuing to screen more medicinal plants and will select those extracts with anti-cancer splicing activity for further studies. These further studies should identify numerous splicing pathways and completely elucidate the splicing target compounds that may serve as novel anti-cancer drugs or lead compounds. Note: This abstract was not presented at the meeting. Citation Format: Zodwa Dlamini, David Bates. Medicinal plants show anticancer splicing activity of apoptotic genes. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5552. doi:10.1158/1538-7445.AM2015-5552

Testing of Eight Medicinal Plant Extracts in Combination with Kresoxim-Methyl for Integrated Control of Botrytis cinerea in Apples

Botrytis cinerea is a fungus that causes gray mold on many fruit crops. Despite the availability of a large number of botryticides, the chemical control of gray mold has been hindered by the emergence of resistant strains. In this paper, tests were done to determine the botryticidal efficacy of selected plant extracts alone or combined with kresoxim-methyl. In total, eight South African medicinal plants viz Artemisia afra, Elyptropappus rhinocerotis, Galenia africana, Hypoxis hemerocallidea, Siphonochilus aetheopicus, Sutherlandia frutescens, Tulbaghia violacea and Tulbaghia alliacea were screened. Allium sativum, a plant species known to have antifungal activity, was included in the in vivo studies. For the in vitro studies, synergistic interactions between the plant extracts and the kresoxim-methyl fungicide were tested with radial growth assays. Data indicated synergistic inhibitory effects between the fungicide and the plant extracts. Next, different doses of plant extracts combined with kresoxim-methyl were used for decay inhibition studies on Granny Smith apples. Synergistic and additive effects were observed for many of the combinations. Even though this study was done using only one strain of B. cinerea, results showed that the tested indigenous South African plant species possess natural compounds that potentiate the activity of kresoxim-methyl.

In-vitro antioxidant and antidiabetic potentials of Dianthus basuticus Burtt Davy whole plant extracts

Dianthus basuticus is a popular South African medicinal plant used in the management of diabetes mellitus. This study evaluated the antioxidant and antidiabetic potential of D. basuticus using an in-vitro model. The antioxidant activity was determined using iron chelation, 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radical scavenging abilities of the aqueous, ethanol and hydro-ethanol extracts of D. basuticus while the antidiabetic potential was assessed by evaluating the inhibitory effects of the extracts on the activities of α-amylase, α-glucosidase, maltase and sucrase. The aqueous extract displayed significantly higher (p<0.05) DPPH (2.56μg/mL) and superoxide radical (7.22μg/mL) scavenging abilities while ethanol (10.56μg/mL) and hydro-ethanol (6.95μg/mL) extracts exhibited strongest hydroxyl radical scavenging and iron chelation activities respectively. The ethanol extract displayed significantly higher (p<0.05) inhibition of α-amylase (34.02μg/mL) while aqueous extract exhibited strongest inhibition of α-glucosidase (6.59μg/mL), maltase (31.21μg/mL) and sucrase (20.98μg/mL). Hydro-ethanol and aqueous extract inhibited α-amylase and α-glucosidase in a mixed non-competitive and pure non-competitive manner respectively while the aqueous extract competitively inhibited both maltase and sucrase activities. It can be concluded that D. basuticus extracts possessed antioxidant and antidiabetic activities, and one of its mechanism of antidiabetic action is through the inhibition of diabetes-related enzymes.

HPLC-Based Activity Profiling for hERG Channel Inhibitors in the South African Medicinal Plant Galenia africana

The human ether-a-go-go-related gene channel is a voltage-activated K(+) channel involved in cardiac action potential. Its inhibition can lead to QT prolongation, and eventually to potentially fatal arrhythmia. Therefore, it is considered a primary antitarget in safety pharmacology. To assess the risk of human ether-a-go-go-related gene channel inhibition by medicinal plants, 700 extracts from different parts of 142 medicinal plants collected in Southern Africa were screened on Xenopus laevis oocytes. A CH2Cl2 extract from the stems and leaves of Galenia africana (Aizoaceae) reduced the peak tail human ether-a-go-go-related gene current by 50.4 ± 5.5 % (n = 3) at a concentration of 100 µg/mL. By means of high-performance liquid chromatography-based activity profiling, nine flavonoids were identified in the active time windows. However, the human ether-a-go-go-related gene channel inhibition of isolated compounds was less pronounced than that of extract and active microfractions (human ether-a-go-go-related gene inhibition between 10.1 ± 5 and 14.1 ± 1.6 at 100 µM). The two major constituents, 7,8-methylenedioxyflavone (1) and 7,8-dimethoxyflavone (13), were quantified (4.3 % and 9.4 %, respectively, in the extract). Further human ether-a-go-go-related gene inhibition tests for compounds 1 and 13 at 300 µM showed a concentration-dependent inhibitory activity (33.2 ± 12.4 and 30.0 ± 7.4, respectively). In a detailed phytochemical profiling of the active extract, a total of 20 phenolic compounds, including six new natural products, were isolated and identified.

Evaluation of nine South African medicinal plants against attenuated Bacillus anthracis strain

Evaluation of nine South African medicinal plants against attenuated Bacillus anthracis strain

Phytochemical and antioxidant investigations of a Clausena anisata hook, a South African medicinal plant

Background: Clausena anisata (Willd). Hook (Rutaceae), also known as Iperepesi in Xhosa language is a medicinal plant widely used by herbalists for the treatment and/or management of several ailments such as chronic cough, tuberculosis and lung ulceration in Eastern Cape, South Africa. With reference to the information gathered in our previous study, we investigated the plant’s phyto-constituents, as well as its inhibitory effects using aqueous and two different organic solvent of extractions in order to justify its folkloric usage.Methods: Antioxidant activity of the plant was screened through 1,1- diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzthiazoline-6- sulfonic acid) (ABTS) diammonium salt, nitric oxide (NO), and ferric reducing power. Total phenols, flavonoids, flavonols, proanthocyanidins, tannins, alkaloids and saponins were investigated using spectroscopic techniques.Results: There were no significant differences in the flavonoid and proanthocyanidins contents between the leaves and bark extracts of C. anisata respectively, while the total phenolic content of the bark extract of C. anisata was significantly higher than that of the C. anisata leaf. The acetone extracts of both the leaf and bark indicated strong antioxidant activities.Conclusion: The observed activities of the plant extracts could be attributed to the high contents of the phenolics, alkaloids, flavonoids, saponins, proanthocyanidins and tannin. The acetone extracts of the plants have also exhibited strong antioxidant activities in vitro. It has been established scientifically that oxidative stress is linked with several degenerative conditions and diseases; the inhibitory effects of these plant extracts on the free radicals could logically justify the folkloric usage of C. anisata leaf and bark in the Eastern Cape for the treatment of respiratory infection diseases.Key words: Antioxidants, Clausena anisata phytochemical contents, solvent extraction antiradical