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Biological and phytochemical screening of major compounds in Cephalanthus natalensisNgwenya, Nomcebo Marcia 02 May 2012 (has links)
M.Sc. / Cephalanthus natalensis of the Rubiaceae family of plants is used in traditional medical systems. Different parts of this shrubby plant are used to treat different ailments. In this study, the use of C. natalensis for medicinal purposes was investigated. Plant materials (leaves, bark and fruits) were collected from different localities in Swaziland. Extraction of phytochemicals in C. natalensis was done by maceration in four solvents of increasing polarities: hexane, dichloromethane, ethyl acetate and methanol. Amino acids and alkaloids were also extracted in boiling water and mild acid, respectively. Phytochemical screening of compounds was done by means of TLC, HPLC and GC-MS. Previously reported TLC screening of C. natalensis indicated the presence of alkaloids. This study also confirmed the presence of alkaloids, although these were not isolated. No other chemical compounds have been reported from this plant in literature. Phenolic compounds and terpenes were extracted and detected by the chromatographic methods employed. GC-MS analysis was also used to identify and quantify amino acids in the extracts. A phytochemical assessment of compounds was done by investigating the leaves, bark and fruits of C. natalensis. A further phytochemical variation study was conducted by comparing these phytochemicals and their relative concentrations in C. natalensis plants collected from five different localities. While the same compounds were present in all the plants sampled, the concentrations of the different compounds seemed to vary irrespective of the geographic location of the plants sampled. In the different plant parts collected, some common compounds were present in the leaves, bark and fruits and other compounds varied between the different parts studied. The traditional usage of C. natalensis as fever and malaria remedy was investigated in vitro. Antibacterial and antimalarial tests of crude extracts were done. The antibacterial test on the extracts against five bacteria: Bacillus cereus, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa showed an average activity in all the plant parts tested. The average MIC values ranged from 0.917 mg/mL to >100 mg/mL. In the antimalarial test the extracts inhibited 50% of Plasmodium falciparum growth at concentrations ranging from 27 μg/mL to >100 μg/mL. Hexane extracts of the bark had notable antimalarial activity with the highest inhibition at the lowest concentration of 27 μg/mL. The fruits were not as active as expected since they are particularly used as malaria remedy in traditional medicine. Two compounds were also isolated from methanol extracts of C. natalensis for the first time. A volatile isoprenoid ketone, (5E,9E)-6,10,14-trimethylpentadeca-5,9,13-trien-2-one, was isolated and characterised. The structure of the second compound could not be completely characterised due to complex data obtained from the NMR experiments.
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Pharmacological evaluation of antidiarrhoeal and antidiabetic activities of Syzygium Cordatum Hochst. ex C. KraussDeliwe, Mzonke January 2011 (has links)
Magister Pharmaceuticae - MPharm / Syzygium cordatum is a medicinal plant indigenous to South Africa and Mozambique, commonly used to treat stomach aches, diabetes, respiratory problems and tuberculosis. In spite of the folklore use, adequate scientific data to credit its widespread traditional use is lacking. The objectives of this study were: to evaluate and validate scientifically the successful therapeutic claims by traditional medicine practitioners that Syzygium cordatum is effective in treating diarrhoea and diabetes; to determine the effects of the plant extract on gastrointestinal transit of a charcoal meal in mice; to determine the effects on castor oilinduced intestinal fluid accumulation; to determine the safety profile of the plant by carrying out acute toxicology study and to carry out preliminary screening of the active compounds present in the plant using standard phytochemical analytical procedures. The aqueous leaf extract of Syzygium cordatum (3.125 -50mg/kg, p.o) significantly reduced the faecal output caused by castor oil (0.7ml). All the doses used, reduced faecal output from 100% produced by castor oil to between 40 and 61%. S.cordatum (6.25 – 50mg/kg, p.o) significantly and in a dose dependent manner, delayed the onset of castor oil-induced diarrhoea. / South Africa
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Etude ethnobotanique, phytochimique et activités biologiques de Nauclea latifolia Smith, une plante médicinale africaine récoltée au Mali / Ethnobotanical, phytochemical and biological activities of Nauclea latifolia Smith, an African medicinal plant harvested in MaliBadiaga, Mamadou 07 December 2011 (has links)
Nauclea latifolia Smith (Rubiaceae) est une plante aux vertus médicinales beaucoup plus connues en Afrique sub-saharienne dans la pharmacopée traditionnelle pour ses nombreuses activités pharmacologiques. N. latifolia Sm. est un arbre ou arbuste d'espèce soudano-sahélienne ; ses zones d'abondance sont principalement l'Afrique Occidentale et Centrale. Sa large utilisation en médecine traditionnelle , nous a incités à réaliser une enquête ethnobotanique et un screening phytochimique afin de mettre en cohérence les prescriptions et les activités potentielles des constituants chimiques présents. Les principales classes de métabolites secondaires, principalement les alcaloïdes, les flavonoïdes, les tanins, les stérols et terpéniques ont été recherchés dans les feuilles, écorces et racines de la plante. N. latifolia Sm. de par la présence des nombreuses familles chimiques, possède des activités biologiques intéressantes. Les extraits d'alcaloïdes totaux issus des 3 organes de la plante, ont prouvé une activité anticancéreuse. Ces extraits inhibent la prolifération des cellules cancéreuses mammaires MCF-7. Outre l'activité antitumorale, les extraits alcaloïdes de N. latifolia Sm. agissent contre la douleur. Ils inhibent en effet de la douleur après injection de l'acide acétique à 0,6 % chez la souris. Cependant, N. latifolia Sm. se présente comme une plante aux nombreux médicaments. Au regard de ces activités biologiques intéressantes, il convient de mener des investigations intenses pour enrichir la production des Médicaments Traditionnels Améliorés (MTA). / Nauclea latifolia Smith (Rubiaceae) is a plant with curative virtues much more known in Sub-Saharan Africa in the traditional pharmacopoeia for the numerous biological activities. N. latifolia Sm.is a shrub or tree Soudano-Sahelian species ; his zones of abundance are in most cases Western and Central Africa. His wide use in traditional medecine incited us to realize an ethnobotany investigation and a phytochemical screening to put in coherence the prescriptions and the potential activities of the chemical constituents. The main classes of metabolites secondary sectors, maily alkaloids, flavonoids, tannins, sterols and terpenoids, were looked for in the leaves, barks of stems and roots. N. latifolia Sm. all over the presence of its numerous chemical families have interesting pharmacological activities. The extracts of existent complete alkaloids of the 3 organs of the plant, proved an anticancerous activities. These extracts inhibit the proliferation of the mammary cancerous cells MCF-7. Besides, activity antitumorale extracts alkaloids of N. latifolia Sm. act against pain. They inhibit the effect of pain after injection acetic acid in 0,6 % to the mice. However, N. latifolia Sm. comes as a plant in numerous drugs. With regard to the interesting biological activities, it is necessary to lead intense investigation to enrich the production of Traditional Ameliorated Drugs.
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Étude phytochimique et biologique de Billia rosea Planch & Lunden, Ulloa & Jorgensen; plante vénézuélienne appartenant à la famille SAPINDACEAE / Phytochemical and biological study of Billia rosea Planch & Lunden, Ulloa & Jorgensen; Venezuelan plant belonging to the SAPINDACEAE family / Estudia fisicoquímica y biológica de Billia rosea Planch & Lunden, Ulloa & Jorgensen; planta venezolana perteneciendo a la familia SAPINDACEAEDe Freitas Fernandez, Luis Antonio 03 April 2018 (has links)
Cette thèse s’inscrit dans le cadre de la thématique du Laboratoire de Pharmacognosie de l’UFR des Sciences de santé, au sein de l’Université de Bourgogne Franche-Comté et du Laboratoire de Produits Naturels de la Faculté de Sciences, au sein de l’Universidad Central de Venezuela. Elle vise essentiellement l’étude phytochimique des graines de Billia rosea (Planch. & Linden) C. Ulloa & P. Jørg, famille des Sapindaceae, qui est utilisé en médecine traditionnelle comme antidiabétique, analgésique et pour le traitement des hémorroïdes et de la fièvre. L'étude de cette espèce végétale a conduit à l’isolement et à la caractérisation de 10 saponines triterpéniques parmi lesquelles 5 sont de structure nouvelle (Billiosides A–E), un analogue connu et une structure a été proposée pour les 4 autres saponines qui devraient être vérifiées dans des études ultérieures.Les structures ont été élucidées principalement par l’utilisation de RMN 1D et 2D (1H, 13C, DEPT, COSY, TOCSY, NOESY, ROESY, HSQC, et HMBC) ainsi que la spectrométrie de masse comme (3β,21β,22α)-3-[(2-O-β-D-glucopyranosyl-O-[α-L-arabinopyranosyl-(1 / 4)]-β-D-glucopyranosyl)oxy]-21-[((2E,6S)-2,6-dimethyl-6-hydroxyocta-2,7-dienoyl)oxy]-22-(acetyloxy)-24-hydroxyolean-12-en-28-oic acid (Billioside A), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-β-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranoside (Billioside B), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-D-xylopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-β-D-glucopyranoside (Billioside C), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-β-Dglucopyranoside (Billioside D), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-Dglucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranoside (Billioside E), et dipteroside A.Les structures proposées pour les 4 autres saponines sont (3β,16α,21β,22α)-3-[(4-O-α-L-arabinopyranosyl-β-D-glucuronopyranosyl)oxi]-22-(acetyloxy)-16,24,28-trihidroxyolean-12-en-21-yl-O-(3,4-di-O-angeloyl)-6-Deoxy-β-D-glucopyranoside, es (3β,16α,21β,22α)-3-[(4-O-α-L- glucuronopyranosyl -β-D-glucuronopyranosyl)oxy]- 16,22,24,28-tetrahidroxyolean-12-en-21-yl-O-(3,4-di-O-angeloyl)-6-Deoxy-β-D-glucopyranoside, (3β,16α,21β,22α)-3-[(2-O- β-D-galactopyranosyl-β-D-glucuronopyranosyl)oxy]-22-(acetyloxy)-16,24,28-trihidroxyolean-12-en-21-yl-O-(3,4-di-O-angeloyl)-6-Deoxy-β-D-glucopyranoside et (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1→4)]-β-D-xylopyranosyl)oxy]-21-acetyl-22-hidroxyolean-12-en-28-yl-O-α-L-arabinopyranosyl-(1→4)-β-D-glucopyranoside.Billiosides B et C ont été testés en vue d’évaluer leurs capacité à inhiber l'absorption intestinale du glucose in situ dans des segments d'intestins de rat, et sa capacité à inhiber le glucose-6-phosphatase, enzyme impliquée dans la formation du glucose. Billiosides B et C ont montré des effets modérés dans les deux expériences. / This thesis was carried out in the the Laboratory of Pharmacognosy, in health department of the University of Burgundy and in the Laboratory of Natural products of Central University of Venezuela.This research work focused on the phytochemical study of the sedes of Billia rosea (Planch. & Linden) C. Ulloa & P. Jørg, Sapindaceae family. Billia rosea seeds have traditionally been used as antidiabetic, analgesic and for the treatment of hemorrhoids and fever. In the study of this plant was isolated and characterized 10 triterpene saponins, among which 5 has a new structure in the literature of natural products (Billiosides A–E), a known analogue and 4 proposals as possible structures to the remaining isolated saponins, which must be confirmed in subsequent studies.Their structures were elucidated on the basis of extensive 1D and 2D NMR experiments (1H, 13C, DEPT, COSY, TOCSY, NOESY, ROESY, HSQC, et HMBC) and mass spectrometry as (3β,21β,22α)-3-[(2-O-β-D-glucopyranosyl-O-[α-L-arabinopyranosyl-(1 / 4)]-β-D-glucopyranosyl)oxy]-21-[((2E,6S)-2,6-dimethyl-6-hydroxyocta-2,7-dienoyl)oxy]-22-(acetyloxy)-24-hydroxyolean-12-en-28-oic acid (Billioside A), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-β-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranoside (Billioside B), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-D-xylopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-β-D-glucopyranoside (Billioside C), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-D-glucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-β-Dglucopyranoside (Billioside D), (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1 → 4)]-β-Dglucopyranosyl)oxy]-21,22-dihydroxyolean-12-en-28-yl O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranoside (Billioside E), and dipteroside A.The proposed structures for the other 4 isolated saponins are (3β,16α,21β,22α)-3-[(4-O-α-L-arabinopyranosyl-β-D-glucuronopyranosyl)oxi]-22-(acetyloxy)-16,24,28-trihidroxyolean-12-en-21-yl-O-(3,4-di-O-angeloyl)-6-Deoxy-β-D-glucopyranoside, es (3β,16α,21β,22α)-3-[(4-O-α-L- glucuronopyranosyl -β-D-glucuronopyranosyl)oxy]- 16,22,24,28-tetrahidroxyolean-12-en-21-yl-O-(3,4-di-O-angeloyl)-6-Deoxy-β-D-glucopyranoside, (3β,16α,21β,22α)-3-[(2-O- β-D-galactopyranosyl-β-D-glucuronopyranosyl)oxy]-22-(acetyloxy)-16,24,28-trihidroxyolean-12-en-21-yl-O-(3,4-di-O-angeloyl)-6-Deoxy-β-D-glucopyranoside and (3β,21β,22α)-3-[(2-O-β-D-galactopyranosyl-O-[α-L-arabinopyranosyl-(1→4)]-β-D-xylopyranosyl)oxy]-21-acetyl-22-hidroxyolean-12-en-28-yl-O-α-L-arabinopyranosyl-(1→4)-β-D-glucopyranoside.Billiosides B and C exhibited moderate effects when tested as hepatic glucose-6-phosphatase inhibitors and as glucose intestinal absorption inhibitors, using in situ rat intestinal segments. / Este trabajo de investigación, realizado en conjunto entre el Laboratorio de Farmacognosia de la Facultad de Ciencias de la Salud, de la Université de Bourgogne Franche-Comté y el Laboratorio de Productos Naturales de la Facultad de Ciencias de la Universidad Central de Venezuela; se centró en el estudio fitoquímico de las semillas de Billia rosea (Planch. & Linden) C. Ulloa & P. Jørg, perteneciente a la familia Sapindaceae, utilizada tradicionalmente como antidiabético, analgésico y para el tratamiento de hemorroides y fiebre. El estudio de esta especie vegetal condujo al aislamiento y caracterización de 9 saponinas triterpénicas, entre las cuales 5 poseen una estreuctura nueva en la literatura de productos naturales (Billiosidos A–E), un análogo conocido, además de 3 propuestas como posibles estructuras a las restantes saponinas aisladas, que deben ser confirmadas en estudios posteriores. Las estructuras se elucidaros principalmente mediante el uso de RMN 1D y 2D (1H, 13C, DEPT, COSY, TOCSY, NOESY, ROESY, HSQC, et HMBC) y espectrometría de masa como ácido (3β,21β,22α)-3-[(2-O-β-D-glucopiranosil-O-[α-L-arabinopiranosil-(1→4)]-β-D-glucopiranosil)oxi]-21-[((2E,6S)-2,6-dimetil-6-hidroxiocta-2,7-dienoil)oxi]-22-(acetiloxi)-24-hidroxiolean-12-en-28-oico, (Billiosido A) (3β,21β,22α)-3-[(2-O-β-D-galactopiranosil-β-D-glucopiranosil)oxi]-21,22-dihidroxiolean-12-en-28-il-O-α-L-arabinopiranosil-(1 → 4)-β-D-glucopiranosido (Billiosido B), (3β,21β,22α)-3-[(2-O-β-D-galactopiranosil-O-[α-L-arabinopiranosil-(1→4)]-β-D-xilopiranosil)oxi]-21,22-dihidroxiolean-12-en-28-il-O-β-D-glucopiranosido (Billiosido C), (3β,21β,22α)-3-[(2-O-β-D-galactopiranosil-O-[α-L-arabinopiranosil-(1 → 4)]-β-D-glucopiranosil) oxi]-21,22-dihidroxiolean-12-en-28-yl-O-β-D-glucopiranosido (Billiosido D), (3β,21β,22α)-3-[(2-O-β-D-galactopiranosil-O-[α-L-arabinopiranosil-(1→4)]-β-D-glucopiranosil)oxi]-21,22-dihidroxiolean-12-en-28-il-O-β-D-glucopiranosil-(1→6)-β-D-glucopiranosido (Billiosido E) y Dipterosido A. Las estructuras propuestas para las otras 3 saponinas aisladas son (3β,16α,21β,22α)-3-[(4-O-α-L-arabinopiranosil-β-D-glucoronopiranosil)oxi]-22-(acetiloxi)-16,24,28-trihidroxiolean-12-en-21-il-O-(3,4-di-O-angeloil)-6-Deoxy-β-D-glucopiranosido, (3β,16α,21β,22α)-3-[(4-O-β-D-galactopiranosil-β-D-glucoronopiranosil)oxi]-22-(acetiloxi)-16,24,28-trihidroxiolean-12-en-21-il-O-(3,4-di-O-angeloil)-6-Deoxy-β-D-glucopiranosido y (3β,21β,22α)-3-[(2-O-β-D-galactopiranosil-O-[α-L-arabinopiranosil-(1→4)]-β-D-xilopiranosil)oxi]-21-acetil-22-hidroxiolean-12-en-28-il-O-α-L-arabinopiranosil-(1→4)-β-D-glucopiranosido. También se evaluó la actividad inhibitoria de los Billiosidos B y C sobre la absorción intestinal de glucosa in situ en segmentos de intestinos de ratas, además de la capacidad inhibitoria de estos compuestos sobre la enzima glucosa-6-fosfatasa, implicada en la formación de glucosa. Estos Billiosidos mostraron efectos moderados en estos dos experimentos
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Elucidating Tomato Steroidal Glycoalkaloid Metabolism and Effects of Consumption onthe Gut Microbiome in a Pig ModelGoggans, Mallory January 2020 (has links)
No description available.
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Targeting shikimate pathway for antimycobacterial drug discovery using traditionally used medical plantsMatotoka, Mashilo Mash January 2022 (has links)
Thesis (Ph.D.(Microbiology)) -- University of Limpopo, 2022 / Respiratory tract infections (RTIs) are frequent ailments among humans and are a
high burden to public health. One strategy for the development of new therapies
against pathogenic bacteria such as Mycobacterium tuberculosis is to target essential
biosynthetic pathways of its metabolism. The aim of this study was to evaluate and
target the biosynthesis of aromatic amino acids (shikimate pathway) of Mycobacterial
spp using medicinal plant extracts. The selection of the plants in this study was based
on their ethnopharmacological use for the treatment of tuberculosis infections and
related symptoms. The leaves were dried at ambient temperatures and ground to fine
powder. The powdered material was extracted with hexane, dichloromethane,
acetone, methanol and water. Phytochemical screening was done using standard
protocols that tested for tannins, saponins, terpenoids, alkaloids, flavonoids, steroids,
anthraquinones, phlobatannins, quinones, and betacynins. Phytochemical fingerprints
were established using thin layer chromatography (TLC) where three mobile phases
varying in polarity were used to develop the chromatograms. Total Phenolics,
flavonoids, flavonols, tannins, alkaloids and proanthocyanidin contents were
quantified using UV/Vis spectrometry. Spectrometric quantification of the free radical
(DPPH) scavenging activity and ferric (potassium ferricyanide) reducing power were
performed. The heat-dependent bovine serum albumin and egg albumin denaturation
assays were used to evaluate anti-inflammatory activity. Antimycobacterial activity
was screened using bioautography assay in qualitative analysis. Quantitatively, broth
microdilution assay was used to determine the minimal inhibitory concentrations. The
Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9
interference genetic editing technique was used to evaluate and validate the
essentiality of the aromatic amino acids in Mycobacteria to further determine the
vulnerability and draggability of the transketolase (tkt) and DAHPs (aroG) genes.
Plasmid, PLJR962, was used for the CRISPRi/dCas9 gene knockdown experiments.
The integrating CRISPRi plasmid expressed both sgRNA with the targeting region (for
tkt or aroG) and the dCas9 handle which is under control of the anhydrotetracycline
(ATC) inducible promoters. The spot assay and growth curves were used to for
phenotypic characterisation and gene knockdown experiments. RNA microarray
(qPCR) was used to evaluate the level of expression inhibition of tkt gene . Mechanism
of action of plants extracts bioactive components were predicted based on synergy
between gene knockdown, shikimate inhibitors and the plant extracts. To evaluate
whether the shikimate intermediates may rescue gene depleted M. smegmatis
hypomorphs, the cultures were grown in L-tryptophan, L-phenylalanine, L-tyrosine and
shikimic acid and growth curves constructed. Cytotoxicity of the extracts was
evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide
(MTT) assay on Vero cell lines and phorbol 12-myristate 13-acetate (PMA)
differentiated THP-1 macrophages. Phytochemical analysis showed that the various
extracts had various polar and non-polar compounds which belonged to phenolics,
saponins, steroids, terpenoids, alkaloids, cardiac glycosides and resins. Numerous
non-polar compounds from Gardernia volkensii, Senna petersiana, Ficus sur had
antimycobacterial activity against M. smegmatis in bioautography. Remarkably,
acetone extracts from S. petersiana, Acacia senegal, Carissa bispinosa, P. africanum
and C. gratissimus that had moderate to low antimycobacterial activity against wild type M. smegmatis (mc2 155) demonstrated improved inhibitory activity against the tkt
PAM1 M. smegmatis CRISPRi mutant. Only the acetone Clerodendrum glabrum,
Croton gratissimus, Peltophorum africanum and Gardenia volkensii demonstrated
activity against M. tuberculosis H37Rv. These results suggest that the employment of
CRISPRi in M. tuberculosis to develop screening models may increase changes of
obtaining bioactive chemical species because the tkt gene knockdown was showed to
possess the ability to potentiate the antimycobacterial activity of the plant extracts. An
added advantage of the plant extracts is their antioxidant and anti-inflammatory
activities which may benefit the host immune system during treatment of infection by
reducing free radicals and pro-inflammatory agents that perpetuate the infection. Non polar compounds were found to generally have higher anti-inflammatory activity than
the polar counterpart for all the plant extracts. These results suggest that the non-polar
compounds from the tested extracts may not only confer antimycobacterial effects, but
also anti-inflammatory activities. A. senegal, G. volkensii, F. sur, S. petersiana and C.
glabrum were found to be toxic to the Vero cell line. However, purification techniques
may circumvent their toxic effects. This study demonstrated that the amino acid
biosynthesis is a potential antimycobacterial drug target because it was found to be
essential, vulnerable and druggable by medicinal plant extracts / University of Limpopo and
National Research Foundation
(NRF-DAAD In-Country Doctoral Scholarship Programme)
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Improvement of the quality and shelf life of traditionally produced sorghum juice by addition of ashes, dried powered leaves and stem obtained from combretum sppMathipa, Morongwa Mary January 2022 (has links)
Thesis (Ph.D.(Microbiology)) -- University of Limpopo, 2022 / Traditional sorghum juice is produced in many African countries for human
consumption. The juice is very rich in calories, B-group vitamins including thiamine,
folic acid, riboflavin, nicotinic acid, and essential amino acids such as lysine. Low
earning income women at village level produce sorghum juice for home consumption
and sale. The short shelf life (2 to 3 days) of sorghum juice is a major problem for both
the brewers and consumers of this drink. The aim of the study was to use 12
Combretum plants to improve the microbiological quality and shelf life of sorghum
juice.
Fresh stems and leaves of C. caffrum, C. vendae, C. erythrophyllum, C. elaegnoides,
C. apiculatum, C. imberbe, C. adenogdium, C. padoides, C. bracteosum, C. kraussii,
C. mkuzense and C. zeyherii were collected at Nelspruit, National Botanical Gardens,
Mpumalanga, South Africa. Voucher specimens and tree labels were used to verify
the identity of the plants. The stems and bark collected were cut into pieces and air dried for 30 days. When dried, the plant material was ground to a fine powder and
stored in paper bags at room temperature. The wood was burnt in an open fire; fuel
was not used to minimise contamination.
The qualitative phytochemical composition of both the leaves and stems of
Combretum plants analysed in this study revealed the presence of saponins, tannins,
terpenoids, steroids, cardiac glycosides and flavonoids. The following
phytoconstituents were lost in the ashes; tannins with the exception of C. mkuzense
and C. padoides; cardiac glycosides and flavonoids. The quantitative phytochemical
analyses revealed that both the leaves, stems and some ashes such as C. apiculatum
and C. vendae contained appreciable levels of phenolic compounds, tannins and
flavonoids.
Quantitative analysis of antioxidant activity, the 2, 2, diphenyl-1-picrylhydrazyl (DPPH)
assay was used as a screen test for the radical scavenging ability of the compounds
present in the different 36 70% acetone extracts. DPPH screening method indicated
great scavenging activity with the 70% acetone leaf extracts of C. kraussii, C. zeyherii
and C. mkuzense. The leaf and stem extracts showed substantial great antioxidant
activity in a concentration-dependent manner. There was a significant decrease in the
antioxidant activity in the ashes (p=001), when compared to both the leaves and the
stems.
The proximate and nutritional analysis of the 70% acetone extracts were performed
by AOAC and ICPE protocols, respectively. The results indicated that all the extracts
had substantial amounts of ash, moisture, protein and energy. Mineral content of the
plant parts was analysed as well, calcium had the highest concentration, while zinc
was lowest in concentration. The mineral content decreased significantly in the stems
(p ≤ 0.05) when compared to the leaves. There was a further decrease in mineral
content with regard to the ashes with the exception of calcium. Based on these
findings, the leaves and ashes of C. adenogonium and C. apiculatum could provide a
good source of calcium in the diet, while C. adenogonium, C. bracteosum and C.
apiculatum had high levels of sodium.
A serial micro-dilution assay was used to determine the minimum inhibitory
concentration (MIC) values for 70% plant extracts using tetrazolium violet reduction as
an indicator of growth. Two Gram-positive (Stapylococcus aureus ATCC 29213 and
Enterobacter faecalis ATCC 29212) and two Gram-negative (Escherichia coli ATCC
25922 and Pseudomonas aeruginosa ATCC 27853) bacterial strains were used in this
study. The leaves had good antibacterial properties with the lowest MIC value being
0.04 mg/ml against E. coli and S. aureus. E. faecalis was found to be resistant against
all the leaves with the exception of C. imberbe. The stem extracts of Combretum spp.
tested in the study showed antimicrobial properties with the lowest MIC value being
0.04 mg/ml against E. coli shown by C. bracteosum. However, E. faecalis was
resistant against all the 12 plants tested. All the test microorganisms showed
resistance to the ashes, with the exception of S. aureus, which was found to be
susceptible to 75% of the test ash extracts with the lowest MIC value of 0.16 mg/ml.
Cytotoxicity and anticancer activity of the acetone extracts of the 12 Combretum plants
were evaluated using tetrazolium-based colorimetric assay (MTT assay) on A549 lung
carcinoma cells. The assays revealed that 50% of the leaf extracts of tested plants
showed cytotoxicity and cell proliferation inhibition in A549 lung carcinoma cells in a
concentration-dependent manner. The A549 cells were more sensitive to the following
plants: C. elaegnoides, C. erythrophyllum C. imberbe, C. kraussii and C. mkuzense.
The following stems extract, C. adenogdium and C. caffrum did not have any anticancer activity, whereas C. apiculatum and C. bracteosum were only able to
reduce cell viability to less than 60%. C. mkuzense, C. padoides, C. vendae and C.
zeyherii acted in a concentration-depended manner with the greatest activity seen at
the highest concentration (1000 µg/ml). The plants had activity at concentrations
between 31.25 and 1000 µg/ml allowing only 20% and 50%, respectively, of the cells
to remain viable. Ashes from C. mkuzense showed good anti-cancer activity at the
highest concentration (1000 µg/ml) reducing cell viability to around 10%.
Enterobacteriaceae, total coliform, S. aureus, B. cereus, E. coli and lactic acid bacteria
viability were studied during the four weeks storage period of prepared sorghum juices.
Juice samples were collected after preparation; the samples were serially diluted using
peptone water. Tempo instrument (Biomereiux) was used to enumerate total coliform,
total aerobic count, E. coli, S. aureus, lactic acid bacteria, enteric bacteria, yeast and
mould using the most probable number following the manufacturers instruction. C.
mkuzense and C. padoides plants were able to inhibit the growth of B. cereus, lactic
acid bacteria and S. aureus during the first three weeks of storage. E. coli was not
present throughout the four weeks storage time. Vitek 2 Compact (Biomereiux) was
used for the characterisation and identification of the dominant bacterial isolates using
biochemical reactions. The isolates were characterised by morphological differences.
Sixty five percent of the isolates were the Enterobacter genus that are commonly found
in soil, water, and sewage.
The nutritional composition and sensory properties of the prepared sorghum juices
treated with Combretum plants were investigated. All the juices had appreciable
amounts of protein, ash and energy. Sorghum juice treated with ashes of C. caffrum,
C. erythrophyllum and C. kraussii had the highest levels of proteins when compared
with other treated sorghum juices. The sorghum juices prepared in the study had
varying levels of trace element or minerals with potassium -(3, 55 – 104 mg/l) and
calcium (3.2-148 mg/l). Similarly, cobalt (-1.22), coppr (-0.99), iron(-0.962),
magnesium (0.004), sodium (-0.145), nickel (-2.7)) and zinc (-1.2)are present in very
low amounts. The juices treated with ashes had relatively higher levels of calcium,
potassium, magnesium and sodium. Sorghum juices treated with the ashes had better
sensory and organoleptic properties when compared with those treated with the
leaves. The juices treated with the ashes of C. caffrum and C. bracteseum were more
accepted by most of the panellist when compared with other treated juices.
Overall, this study presents valuable information on the phytochemical composition,
nutritional composition and antioxidant properties of some Combretum species in
South Africa. It recommended its use as food and in pharmaceutical preparations for
the local industries. In addition, Combretum plants showing the effects tested in this
study may be explored further for development into drugs. functional food as food
preservatives and nutraceutical applications, beside their traditional use / University of Limpopo and
Foodbev SETA
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A Detailed Review on the Phytochemical Profiles and Anti-Diabetic Mechanisms of Momordica CharantiaOyelere, Sunday F., Ajayi, Oluwatobi H., Ayoade, Titilayo E., Santana Pereira, George Bueno, Dayo Owoyemi, Bolaji C., Ilesanmi, Ajibola O., Akinyemi, Olalekan A. 01 April 2022 (has links)
Diabetes mellitus is the most well-known endocrine dilemma suffered by hundreds of million people globally, with an annual mortality of more than one million people. This high mortality rate highlights the need for in-depth study of anti-diabetic agents. This review explores the phytochemical contents and anti-diabetic mechanisms of (cucurbitaceae). Studies show that contains several phytochemicals that have hypoglycemic effects, thus, the plant may be effective in the treatment/management of diabetes mellitus. Also, the biochemical and physiological basis of anti-diabetic actions is explained. exhibits its anti-diabetic effects via the suppression of MAPKs and NF-κβin pancreatic cells, promoting glucose and fatty acids catabolism, stimulating fatty acids absorption, inducing insulin production, ameliorating insulin resistance, activating AMPK pathway, and inhibiting glucose metabolism enzymes (fructose-1,6-bisphosphate and glucose-6-phosphatase). Reviewed literature was obtained from credible sources such as PubMed, Scopus, and Web of Science.
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Effects Of A Plant-Based Vegan Diet On The Risk Of Cancer: An Integrative Review Of The LiteratureSilavent, Chelsie M 01 January 2019 (has links)
Cancer, an aggressive chronic disease, impacts the lives of millions of people every day. There are numerous proposed triggers related to the diagnosis and much remains to be learned about the causes. Associated with this disease's variability is the challenge to identify a single causative agent that lead to its prevention. Specific topics that need additional evidence relate to environmental factors and lifestyle behaviors in the development, treatment and, in some instances, even suppression of disease progression. Specifically, a diet that excludes animal-based products but consists of a variety of fruits and vegetables (i.e., plant-based vegan diet) is reported to retard disease progression among some individuals diagnosed with cancer. The purpose of this thesis was to examine the effects of a plant-based vegan diet as a treatment approach with individuals who have been diagnosed with cancer. The methodology included a systematic review of literature focusing on use of a plant-based vegan diet on cancer risks in research articles published in peer reviewed journals from 2006 to 2018. Consistent findings include evidence that a diet high in fruits, vegetables, whole grains, and minimal amounts of animal products showed a decrease risk of the development of various types of cancer. Recommendations for nursing education, practice, policy and research are discussed.
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The Biology of Plant-Mosquito AssociationsEbrahimi, Babak January 2013 (has links)
No description available.
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