Pharmacological, toxicological and phytochemical evaluation of helichrysum petiolare hilliard & b.l. burtt - an indigenous plant traditionally used in the treatment of diabetes in the eastern cape province of South Africa
- Authors: Aladejana, Adebowale Emmanuel https://orcid.org/0000-0003-1871-926X
- Date: 2022-04
- Subjects: Diabetes -- Alternative treatment , Traditional medicine , Medicinal plants
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/22787 , vital:52755
- Description: Diabetes mellitus is one of the leading causes of death in South Africa, and it has already placed significant stress on the country’s health sector and economy. The orthodox hypoglycaemic drugs are not only ineffective in the management of the disease and its complications, but they also possess unwanted side effects. The need for alternative non-toxic drugs is therefore imperative. Various studies have listed several medicinal plants that can be successfully used in the herbal treatment of diabetes and have investigated them for their anti-diabetic potentials in vivo and/or in vitro. Out of the different potential herbal species, plants belonging to the Asteraceae family possess highly potent hypoglycaemic properties with negligible toxicities. Five Asteraceae plants widely used in different parts of South Africa for the treatment of diabetes were reviewed. The review provided an update of scientific evidence on the hypoglycaemic properties of the plants. However, Helichrysum petiolare was studied extensively in this study for its antidiabetic activity H. petiolare has been listed in many ethnobotanical surveys as a plant with potent hypoglycaemic potential, this, however, has not been properly verified in scientific literature and there has hardly been any study on the essential oil and nutritional composition, and antioxidant, antidiabetic, and cytotoxicity potentials of the plant. The effects of hydro-distillation (HD) and solvent-free microwave extraction (SFME) methods on the chemical constituents of H. petiolare-derived essential oils were evaluated. The SFME method had a higher yield of essential oil than the HD. There were substantial amounts of monoterpenes, monoterpene alcohols, sesquiterpenes, and sesquiterpene alcohols in both essential oils obtained, but these compounds were more profound in the SFME derived essential oil which has 62 compounds compared to the 52 derived through HD. The SFME derived essential oil can therefore be said to be of better quality than the HD method. The compounds obtained in the essential oils have high pharmaceutical and cosmetic value, and as observed in this study, their quantity is dependent on the method of extraction (Ibáñez and Blázquez, 2021; Kaur et al., 2021). The proximate analysis of the whole plant of H. petiolare showed high levels of Acid Detergent Fibre (ADF), vitamins (A, C and E), Neutral Detergent Fibre (NDF), and minerals. The high ADF level is believed to be responsible for the low energy, fat and carbohydrate levels observed in the study. The result showed a high level of oxalate and therefore suggests cooking of the plant before human consumption. Overall nutrition and mineral compositions of the plant showed that H. petiolare is immensely rich in vital nutrients that are of great importance to health and metabolism; these nutrients are suggested to be partly responsible for the plant’s useful medicinal properties. The phytochemical contents of the acetone (ACQ), ethanol (ETQ), and boiled (BAQ) and cold (CAQ) aqueous whole-plant extracts of Helichrysum petiolare were determined using standard phytochemical reaction methods. ABTS, DPPH, NO and TAC assays were used to evaluate their antioxidant properties. The highest total phenolic content (212,963 mg/g) was reported in the BAQ extract, while the ETQ had the highest flavonoid (172.393 mg/g) and proanthocyanidin contents (65.855 mg/g). Alkaloids, flavonols, and saponin were highest in the ACQ extract, while the CAQ had the lowest phytochemical content. Among the extracts, the BAQ had the highest DPPH•+ (IC50 0.02 mg/mL) and ABTS•+ (IC50 0.07) inhibition capacities, while the ETQ exhibited the highest NO• Inhibition (IC50 0.41 mg/mL) and TAC (IC50 0.19 mg/mL). These findings justify the use of H. petiolare in traditional medicine and further recommend the ETQ and BAQ extracts of the plant as more effective extracts for medicinal treatment. The hepatotoxicity (cytotoxicity, mitotoxicity and lipotoxicity) potential of the BAQ, CAQ and ETQ extracts of Helichrysum petiolare was evaluated using standard procedures. The results showed negligible BAQ and CAQ cytotoxicities, which were further, corroborated by stability in the mitochondrial membrane potentials and were congruent with the CAQ and BAQ results for steatosis and phospholipidosis. The data suggested favourable CAQ and BAQ toxicity profiles with limited risks for hepatotoxicity. The ETQ extract, however, showed significantly high levels of cytotoxicity and lipotoxicity, and a low level of mitotoxicity. Our result suggested a potential risk of the ETQ extract for hepatotoxicity but appears partly independent of direct mitochondrial involvement. Glucose uptake assay showed significantly increased glucose uptake in the BAQ and CAQ treated L6 and C3A cell lines. The CAQ extract enhanced glucose uptake more in the L6 myocytes than in the C3A cell-lines hepatocytes. The BAQ extract showed higher levels of inhibition on α–amylase and α-glucosidase activities as compared to CAQ. The BAQ and CAQ extracts of H. petiolare may, therefore, contain pharmacologically active and relatively non-toxic hypoglycaemic chemicals, which may be effective substitutes in the treatment of diabetes mellitus. This study provides up to date scientific information on the use of H. petiolare in the treatment of diabetes mellitus in the Eastern Cape of South Africa. It justifies the use of this plant in herbal medicine and sheds more light on its previously vaguely understood nutritional and medicinal potentials. More studies, however, need to be done to isolate, identify and purify the constituent bioactive compound(s). Their dosage of application and mode of action also needs to be understood. , Thesis (PhD) -- Faculty of Science and Agriculture, 2022
- Full Text:
Phytochemical analysis and antibacterial properties of aqueous and ethanol extracts of Brachylaena elliptica (Thurb.) dc. and Brachylaena ilicifolia (Lam.) Phill & Schweick
- Authors: Sagbo, Idowu Jonas
- Date: 2015
- Subjects: Medicinal plants , Traditional medicine , Herbs -- Therapeutic use
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11297 , http://hdl.handle.net/10353/d1021289 , Medicinal plants , Traditional medicine , Herbs -- Therapeutic use
- Description: Resistance of human pathogenic bacterial strains results in selective pressure against known antibiotic. However, plant derived compounds that possess antibacterial potential are currently being investigated for treatment of wound infections in diabetic patients as they are inexpensive and non-toxic. Hence, this dissertation was designed to evaluate two medicinal plants (Brachylaena elliptica and Brachylaena ilicifolia) traditionally used in the treatment of various diseases such as diabetes, and its secondary complications in diabetic patients. The in vitro antioxidant activity of both plants were evaluated using DPPH (1, 1-diphenylhydrazl), ferric reducing power, ABTS (2, 2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid), NO (nitric oxide) and H2O2 (hydrogen peroxide) techniques. The antibacterial test and Minimum inhibitory concentration (MIC) was determined by agar dilution method against 5 bacteria strains (Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogene, Proteus vulgaris and Proteus mirabilis) infecting wounds in diabetic patients using amoxicillin and ciprofloxacin as positive control. The phytochemical analyses were assessed using standard published methods. Identification of bioactive components in essential oils of both plants were assessed using GCMS. The aqueous and ethanol extracts of both plants were also evaluated to identify bioactive components using LC-MS. The results of the phytochemical analysis revealed the presence of phenols, tannins, flavanoids, flavanols, proanthocyanidins, saponins and alkaloids in both plants. Both plants indicated strong antioxidant activities which might be due to the presence of bioactive compounds. The aqueous and ethanol leaf extracts of both plants demonstrated appreciable broad spectrum activities against these wound pathogens with MIC ranging between 5 and 0.3 mg/ml. The GC-MS analysis of the essential oils of both plants revealed the presence of monoterpenes, oxygenated sesquiterpenes, phenolics and esters. The LC-MS analysis of the aqueous and ethanol leaf extracts of both plants showed that both plants are rich in alkaloids, terpenes, terpenoids, monoterpernoids, and flavanoids. Conclusively, this study has partially justified the ethnomedicinal use of B. elliptica and B.licifolia leaves for the treatment of various diseases, including diabetes and wound infections caused by bacteria in diabetic patients. These may be attributed to the presence of antioxidant compound such as phenols, flavanoids, saponins, tannins, alkaloids and other phytochemical compounds.
- Full Text:
Assessment of the anti-Listerial properties of Garcinia kola (Heckel) seeds
- Authors: Penduka, Dambudzo
- Date: 2014
- Subjects: Microbial sensitivity tests , Garcinia , Medicinal plants , Traditional medicine
- Language: English
- Type: Thesis , Doctoral , PhD (Microbiology)
- Identifier: vital:11278 , http://hdl.handle.net/10353/d1015527 , Microbial sensitivity tests , Garcinia , Medicinal plants , Traditional medicine
- Description: A follow-up of traditional medicinal plants uses is an important tool in highlighting their therapeutic potentials, as they have been found to be a source of a wide range of bioactive compounds that can be used as base compounds for new pharmaceutical drugs. This study therefore focuses on assessing the anti-Listerial properties of the seeds of Garcinia kola (Heckel) plant, which is a traditional medicinal plant of west and central African origin, and was and is still used to traditionally treat several ailments. Four different solvents crude extracts of the seeds were assessed for their anti-Listerial activities in-vitro, against a panel of 42 Listeria bacteria, which included Listeria monocytogenes, Listeria ivanovii and Listeria grayi species. At 10 mg/ml concentration the aqueous extract had activity against 29% of the test isolates while the other three crude extracts namely dichloromethane, n-hexane and the methanol extracts had activity against 45% of the test bacteria. The minimum inhibitory concentration (MIC) ranges of the extracts were 0.079-0.313 mg/ml for the dichloromethane extract; 0.079-0.625 mg/ml for the n-hexane extract; 0.157-0.625 mg/ml for the methanol extract; and 10->10 mg/ml for the aqueous extract. The minimum bactericidal concentration (MBC) ranges of the extracts were 0.625–10 mg/ml for both the n-hexane and the dichloromethane extract; 5-10 mg/ml for the methanol extract; and those for the aqueous extract were above 10 mg/ml against all the susceptible Listeria isolates. The rate of kill analysis was then determined for the three most active crude extracts that is excluding the aqueous extract and it was assessed against four representative Listeria species namely L. monocytogenes (LAL 8), L. grayi (LAL 15), L. ivanovii (LEL 30) and L. ivanovii (LEL 18). All the three extracts showed a general trend of being concentration and time dependent in their rate of kill profiles such that most bacteria cells were killed at the highest test concentration of 4× MIC value after the maximum exposure time of 2 h. The n-hexane, dichloromethane and methanol extracts were bactericidal against 4, 3 and 1 isolates out of the four test Listeria isolates respectively.
- Full Text:
Incidence of Staphylococcus species in bovine milk: their antimicrobial sensitivity in selected antibiotics and Usnea barbata lichen extracts
- Authors: Idamokoro, Emrobowansan Monday
- Date: 2013
- Subjects: Staphylococcus , Microbial sensitivity tests , Traditional medicine , Lichens -- Analysis , Mastitis , Antibiotics in agriculture
- Language: English
- Type: Thesis , Masters , MSc Agric (Animal Science)
- Identifier: vital:11829 , http://hdl.handle.net/10353/d1016193 , Staphylococcus , Microbial sensitivity tests , Traditional medicine , Lichens -- Analysis , Mastitis , Antibiotics in agriculture
- Description: This study was done in order to assess the incidence of Staphylococcus species from milk of cows with subclinical mastitis and their antimicrobial sensitivity in some selected antibiotics and Usnea barbata lichen extracts. The study was conducted in two different commercial dairy farms. Staphylococcus species isolates were identified using several biochemical tests which included Gram’s staining test, catalase test and oxidase test. A commercial API® staph kit (bioMerieux, France) was used to confirm the bacterial organisms to their species level. The antimicrobial sensitivity of individual species was determined according to the Clinical Laboratory Standard Institute (CLSI) for the selected antibiotics. Agar well diffusion method and the broth micro-dilution technique were used to determine the sensitivity of Staphylococcus species in U. barbata extracts. A total of 467 milk samples were screened for bacterial identification from the two farms. Fifteen different Staphylococcus species isolates were identified from all milk samples that were examined. The most frequently isolated species included Staphylococcus xylosus (54.34%), Staphylococcus hominis (24.78%), Staphylococcus aureus (16.38%), Staphylococcus saprophyticus (16.12%) and Staphylococcus haemolyticus (11.63%). Most Staphylococcus species were resistant to Penicillin (75.35%), Nalidixic acid (72.55%) and Ampicillin (63%). Furthermore, the bacterial sensitivity evaluation of U. barbata lichen extracted with methanol and ethyl-acetate against selected Staphylococcus species isolates showed 92.31% and 53.85% susceptibility, respectively. The minimum inhibitory concentration (MIC) of the methanol and ethyl-acetate extracts ranged between 0.0390 to 10 mg/ml. There was a relatively high incidence of Staphylococcus species identified in milk of cows with subclinical mastitis from both farms. Conversely, Staphylococcus species isolates were resistant to antibiotics (mostly penicillin and ampicillin) commonly used in the farms. Furthermore, the study investigated the antimicrobial sensitivity of U. barbata extract in-vitro which may validate its use in traditional medicine for treatment of cows with mastitis.
- Full Text:
Phytochemical analyses and Brine shrimp (Artemia Salina) lethality studies on Syzygium cordatum
- Authors: Chiguvare, Herbert
- Date: 2013
- Subjects: Artemia , Crustacea , Chromatographic analysis , Medicinal plants , Essences and essential oils , Traditional medicine
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11336 , http://hdl.handle.net/10353/d1004352 , Artemia , Crustacea , Chromatographic analysis , Medicinal plants , Essences and essential oils , Traditional medicine
- Description: Syzygium cordatum Hoscht ex. C Krauss, also known as water berry, is normally used by the people of South Africa for respiratory ailments including tuberculosis, stomach complaints, treatment of wounds and as emetics. An extract of the leaves can be used as a purgative for diarrhoea treatment. The leaves of Syzygium cordatum Myrtaceae were obtained from the Eastern Cape Province of South Africa, air dried and sequential solvent extraction was done to obtain various non volatile crude extracts. The volatile extract, that is the essential oil was extracted from the leaves using hydrodistillation and analysis of compounds was done by GC/MS for composition. 32 compounds were obtained from the fresh leaves and 18 compounds were obtained from the dry leaves. The fresh oil contains caryophyllene (11.8 percent) and caryophyllene oxide (11.1 percent) as the main sesquiterpene component. α-Pinene(5.0 percent) was the only monoterpene compound identified in the fresh oil in substantial amount. The dry leaves oil had copanene (17.0 percent), β-Caryophellene (26.0 percent), cubenol (6.5 percent) and caryophellene oxide (14.2 percent) as the dominant constituent of the oil. Summary of the classes of compounds in the oil revealed that the chemical profile of both oils were dominated by sesquiterpenoid compounds. This is the first time that terpenoids compounds are being identified in both the fresh and dry leaf oil of S. cordatum. Hexane leaf extract was selected due to the interest in the terpenoid compounds. Column chromatography of the hexane crude gave five (5) of which two are fully reported. The isolates were fully elucidated using spectroscopic methods to be β-Sitosterol (HC3) and Friedela-3-one (HC1A/HC1D). Cytotoxicity analysis was carried out on the crude using the Brine shrimps assay. Isolates 1C and1D showed significant lethality using the brine shrimps assay with lethality values (LC50) of 4.105mg/ml for HC1C and 4.11mg/ml for 1D/1A respectively.
- Full Text:
Inhibitory potential of honey on the enzymatic activity of Helicobacter pylori urease
- Authors: Matongo, Fredrick
- Date: 2012
- Subjects: Honey , Helicobacter pylori infections , Enzyme inhibitors , Traditional medicine , Antifungal agents
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11253 , http://hdl.handle.net/10353/431 , Honey , Helicobacter pylori infections , Enzyme inhibitors , Traditional medicine , Antifungal agents
- Description: Urease of Helicobacter pylori is an important virulence factor implicated in the pathogenesis of many clinical conditions, such as chronic gastritis, peptic ulceration, and gastric cancer. Many urease inhibitors have been discovered, like phosphorodiamidates, hydroxamic acid derivatives, and imidazoles. Despite good activities at the enzyme level and excellent kinetic properties most of them have not been used as therapeutic agents in vivo because of their side effects, toxicity and instability. This has led to much attention to focus on exploring the novel urease inhibitory activities of natural products because of their low toxicity and good bioavailability. Honey, a natural product has been used in folk medicine due to its antitumor, antioxidant, antimicrobial and anti-inflammatory properties. The aims of this study were to isolate, characterise, purify urease produced by H. pylori and investigate the inhibitory effects of solvent honey extracts on its enzymatic activity. Urease was found to be both surface-associated and cytoplasmic. Maximum cytoplasmic urease activity was found to occur after 72 hr whereas maximum extracellular urease activities were found to occur after 96 hr. Characterization of the crude cytoplasmic urease revealed optimal activity at a pH of 7.5 and temperature of 40°C. The kinetic parameters Vmax and Km were 45.32 U ml-1 and 61.11 mM respectively.The honey extracts inhibited the activity of the crude urease in a concentration dependent manner. The Lineweaver-Burk plots indicated a non-competitive type of inhibition against H. pylori urease. The two honey extracts gave promising inhibitory activities against urease of H. pylori. Thus the results of this study delineates that inhibition of urease can ease development in therapeutic and preventative approaches based on the enzymatic activity of this Helicobacter protein.
- Full Text:
Phytochemical analysis and bioactivity of Garcinia Kola (Heckel) seeds on selected bacterial pathogens
- Authors: Seanego, Christinah Tshephisho
- Date: 2012
- Subjects: Drug resistance in microorganisms , Garcinia , Antibiotics , Medicinal plants , Microbial sensitivity tests , Streptococcal infections , Streptococcus , Staphylococcus aureus infections , Salmonella typhimurium , Traditional medicine
- Language: English
- Type: Thesis , Masters , MSc (Microbiology)
- Identifier: vital:11259 , http://hdl.handle.net/10353/420 , Drug resistance in microorganisms , Garcinia , Antibiotics , Medicinal plants , Microbial sensitivity tests , Streptococcal infections , Streptococcus , Staphylococcus aureus infections , Salmonella typhimurium , Traditional medicine
- Description: Garcinia kola is one of the plants used in folklore remedies for the treatment of microbial infections. Bacterial resistance to commonly used antibiotics has necessitated the search for newer and alternative compounds for the treatment of drug resistant microbial infections. This study focuses on the bioactivity of G. kola seeds on Streptococcus pyogenes (ATCC 49399), Staphylococcus aureus (NCTC 6571), Plesiomonas Shigelloides (ATCC 51903) and Salmonella typhimurium (ATCC 13311), organisms which can cause illnesses from mild to severe with potentially fatal outcomes. The crude ethyl acetate, ethanol, methanol, acetone and aqueous extracts were screened by agar-well diffusion method and the activities of the extract were further determined by Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays. The inhibition zones ranged from 0 - 24 mm, while MIC and MBC of the extract ranged between 0.04 - 1.25 mg/mL and 0.081 - 2.5 mg/mL respectively. Chloroform/ Ethyl Acetate/ Formic acid (CEF) solvent system separated more active compounds followed by Ethyl Acetate/ Methanol/ Water (EMW) and Benzene/ Ethanol/ Ammonium Hydroxide (BEA). The extracts were fractionated by Thin Layer Chromatography (TLC). Bioautography was used to assess the activity of the possible classes of compounds present in the more active extracts. Column chromatography was used to purify the active compounds from the mixture while Gas Chromatography-Mass Spectrometry (GC-MS) was used to identify the phyto components of the fractions. The MIC of the fractions ranged between 0.0006 - 2.5 mg/mL. CEF 3 (F3), CEF 11 (F11) and CEF 12 (F12) revealed the presence of high levels fatty acids Linoleic acid, 1, 2-Benzenedicarboxylic acid and 2, 3-Dihydro-3, 5-dihydroxy-6-methyl, respectively. The results obtained from this study justify the use of this plant in traditional medicine and provide leads which could be further exploited for the development of new and potent antimicrobials.
- Full Text: