33 research outputs found
Are plants used for skin care in South Africa fully explored?
No AbstractUniversity of Pretoria, and National Research Foundation, South Africahttp://www.elsevier.com/locate/jethpharmhb201
Antibacterial and anti-inflammatory effects of Syzygium jambos L. (Alston) and isolated compounds on acne vulgaris
Acne vulgaris is a chronic skin disorder leading to inflammation as a result of the production of
reactive oxygen species due to the active involvement of Propionibacterium acnes (P. acnes) in the infection site of
the skin. The current study was designed to assess the potential of the leaf extract of Syzygium jambos L. (Alston)
and its compounds for antibacterial and anti-inflammatory activity against the pathogenic P. acnes. The broth dilution method was used to assess the antibacterial activity. The cytotoxicity investigation on
mouse melanocyte (B16-F10) and human leukemic monocyte lymphoma (U937) cells was done using sodium
3’-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitrobenzene sulfonic acid hydrate (XTT) reagent.
The non-toxic concentrations of the samples was investigated for the suppression of cytokines interleukin 8 (IL 8)
and tumour necrosis factor (TNF α) by testing the supernatants in the co-culture of the human U937 cells and
heat killed P. acnes using enzyme immunoassay kits (ELISA). The statistical analysis was done using the Graph Pad
Prism 4 program
The potential of leucosidea sericea against propionibacterium acnes
The present study reports on the potential of Leucosidea sericea addressing acne vulgaris. Four known compounds namely phytol acetate, triacontanol, phytol and alpha kosin and one new compound namely, (E)-3,7,11,15-tetramethylheptadec-2-ene-1,17-diol have been isolated for the first time from this plant. The ethanol extract of leaves and one of the isolated compounds, alpha kosin exhibited significant minimum inhibitory concentration (with MIC values 15.7 μg/mL and 1.9 μg/mL, respectively) against acne inducing bacteria, Propionibacterium acnes. Moreover, the transmission electron micrographs showed the efflux of intracellular content of the cells of P. acnes caused by plant extract and alpha kosin. The ethanol extract of L. sericea exhibited significant anti-inflammatory activity by suppressing interleukin 8 (IL 8) and tumour necrosis factor (TNF α) in coculture of human U937 cells and heat killed P. acnes at concentrations of 25.0, 12.5 and 6.2 μg/mL
Investigation towards propagation and cosmeceutical application of Athrixia phylicoides DC
The multitude of ailments related to human health has become a worldwide open challenge for scholars waged in the field of drug development. Plants have always been a gifted source of alternative medicine for countless disorders. The bush tea (Athrixia phylicoides DC.) is a South African indigenous plant with a diverse range of medicinal properties including cosmetic and antimicrobial properties. This plant has been used in different local communities to treat various ailments. Further, in rural areas it is popularly used as tea by the native people of South Africa. The present study was carried out to evaluate the effects of altered exogenous growth regulators in cutting production of bush tea in two dissimilar seasons. Based on the plant’s traditional usage in cosmetics, the tyrosinase inhibition and antimicrobial potential against the strain Propionibacterium acnes were also investigated. In the propagation study, Indole-3-butyric acid (IBA) was found to have the highest rooting and sprouting percentage during spring, while 1-Naphthalene acetic acid (NAA) was found to promote the highest sprouting and rooting percentage during autumn. Both NAA and IBA improved the number of roots produced compared to that of the control, although not significantly. The addition of exogenous growth regulators is beneficial to obtain significantly more roots per cutting and increase the cutting production of A. phylicoides but did not affect the number of leaves. Although the tyrosinase inhibitory activity was found to be higher in plants from spring as compared to the other seasons it did not compare with the positive control.The National Research Foundationhttp://www.elsevier.com/locate/sajb2018-09-30hj2017Plant Production and Soil Scienc
Antibacterial and anti-inflammatory effects of Syzygium jambos L. (Alston) and isolated compounds on acne vulgaris
BACKGROUND: Acne vulgaris is a chronic skin disorder leading to inflammation as a result of the production of
reactive oxygen species due to the active involvement of Propionibacterium acnes (P. acnes) in the infection site of
the skin. The current study was designed to assess the potential of the leaf extract of Syzygium jambos L. (Alston)
and its compounds for antibacterial and anti-inflammatory activity against the pathogenic P. acnes.
METHODS: The broth dilution method was used to assess the antibacterial activity. The cytotoxicity investigation on
mouse melanocyte (B16-F10) and human leukemic monocyte lymphoma (U937) cells was done using sodium
3’-[1-(phenyl amino-carbonyl)-3,4-tetrazolium]-bis-[4-methoxy-6-nitrobenzene sulfonic acid hydrate (XTT) reagent.
The non-toxic concentrations of the samples was investigated for the suppression of cytokines interleukin 8 (IL 8)
and tumour necrosis factor (TNF α) by testing the supernatants in the co-culture of the human U937 cells and
heat killed P. acnes using enzyme immunoassay kits (ELISA). The statistical analysis was done using the Graph Pad
Prism 4 program.
RESULTS: Bioassay guided isolation of ethanol extract of the leaves of S. jambos led to the isolation of three known
compounds namely; squalene, an anacardic acid analogue and ursolic acid which are reported for the first time
from this plant. The ethanol extract of S. jambos and one of the isolated compound namely, anacardic acid
analogue were able to inhibit the growth of P. acnes with a noteworthy minimum inhibitory concentration (MIC)
value of 31.3 and 7.9 μg/ml, respectively. The ethanol extract and three commercially acquired compounds namely;
myricetin, myricitrin, gallic acid exhibited significant antioxidant activity with fifty percent inhibitory concentration
(IC50) ranging between 0.8-1.9 μg/ml which was comparable to that of vitamin C, the reference antioxidant agent.
The plant extract, compounds ursolic acid and myricitrin (commercially acquired) significantly inhibited the release
of inflammatory cytokines IL 8 and TNF α by suppressing them by 74 - 99%. TEM micrographs showed the lethal
effects of selected samples against P. acnes.
CONCLUSIONS: The interesting antibacterial, antioxidant and anti-inflammatory effects of S. jambos shown in the
present study warrant its further investigation in clinical studies for a possible alternative anti-acne agent.University of Pretoria and National Research Foundationhttp://www.biomedcentral.com/bmccomplementalternmedam201
In vitro and in vivo activity of Myrsine africana on elastase inhibition and anti-wrinkle activity
BACKGROUND : Myrsine africana (MA) is a plant traditionally used in South
Africa to treat various diseases. OBJECTIVE : The ethanolic extract of MA,
was used for in vitro and in vivo studies to determine its elastase inhibitory
activity. MATERIALS AND METHODS : MA and its isolated compound,
myrsinoside B, were tested in vitro for their elastase inhibitory activity.
The MA extract was also evaluated for mutagenicity using two strains
of Salmonella typhimurium (TA 98 and TA 100), microbial count, metal
analysis, and stability. In vivo studies included irritancy and wrinkle
reduction trials using Visioscan and Visioface. RESULTS : The leaf extract
showed good elastase inhibition with a 50% inhibitory concentration (IC50)
of 28.04 µg/ml. Myrsinoside B inhibited the elastase enzyme at an IC50
of 4.68 ± 0.34 μg/ml. No colony growth observed during mutagenicity
studies and it was concluded that MA ethanolic extract is a nonmutagen.
MA extract was found to be a nonirritant during the patch test clinical trial.
MA was found to contain negligible amounts of microorganisms and heavy
metals. Gel cream containing MA crude extract was found to be stable for
2 years when kept at temperatures below 30°C. In clinical trials (in vivo), it
was found that the test product containing 5% ethanolic extract of MA was
effective in reducing wrinkles after application 2 times a day for 14 days
and 28 days compared to the placebo aqueous cream. CONCLUSION : MA is
effective in reducing the appearance of wrinkles.http://www.phcog.comam2018Plant Production and Soil Scienc
Natural products as leads to potential mosquitocides
Mosquitoes are the crucial vectors for a
number of mosquito-borne infectious diseases i.e.
dengue, yellow fever, chikungunya, malaria, Rift
Valley fever, elephantiasis, Japanese Encephalitis,
and Murray Valley encephalitis etc. Besides, they also
transmit numerous arboviruses (arthropod-borne
viruses) for example West Nile virus, Saint Louis
encephalitis virus, Eastern equine encephalomyelitis
virus, Everglades virus, Highlands J virus, and La
Crosse Encephalitis virus. The emergence of widespread
insecticide resistance and the potential environmental
issues associated with some synthetic
insecticides (such as DDT) has indicated that additional
approaches to control the proliferation of
mosquito population would be an urgent priority
research. The present review highlights some natural
product mosquitocides that are target-specific, biodegradable,
environmentally safe, and botanicals in
origin.Department of Plant Science, University of Pretoria, South Africa, Department of Chemistry, Banaras Hindu University,India and National Research Foundation.http://link.springer.com/journal/11101hb201
The effect of Helichrysum odoratissimum (L.) sweet on cancer cell proliferation and cytokine production
The cytotoxicity of Helichrysum odoratissimum against human epidermoid carcinoma (A431), malignant melanoma (A375), cervical epithelial carcinoma (HeLa) and human embryonic kidney (HEK-293) cells was investigated. The cytokine production and antioxidant activity was also determined. H odoratissimum was selected based on its traditional usage as a dressing for wounds. In this study the cytotoxicity was performed on skin and cervical cancer which are associated with the presence of wounds. H. odoratissimum showed inhibitory activity against A431 cells, with a fifty percent inhibitory concentration (IC50) of 15.5±0.2 μg/ml, and a high DPPH inhibition with an IC50 of 5.13±0.07 μg/ml. A431 cells treated with the extract showed an increase in morphological characteristics associated with apoptosis. The extract induced IL-12 in U937 cells and inhibited IL-8 at the tested concentrations, with the highest levels being 12.4±7 pg/ml and 103±6.1 pg/ml respectively. IL-2 was inhibited by 56 % and 52 % in naive and PHA induced murine splenocytes respectively. Furthermore, 2 lipophilic fractions and 3 compounds were isolated from the extract. The lipophilic fractions showed relative cytotoxicity on A431 cells with IC50 values of 175±13.5 μg/ml and 61.3±0.16 μg/ml. The extract showed significant hepatoprotection at 25 μg/ml on HepG2 cells exposed to D-Galactosamine. This is the first report of the activity of H. odoratissimum ethanolic leaf stem extract on A431, A375, HeLa and HEK-293 cell lines as well as the isolation of two promising lipophilic fractions.The University of Pretoria, the National Research Foundation and the Department of Science and Technology.http://ijppr.comam2018Plant Production and Soil Scienc
Alkaloids from aerial parts of Annona senegalensis against Streptococcus mutans
Antimicrobial potential of medicinal plants have been explored
extensively these days. This study was carried out to evaluate the
antibacterial potential from aerial parts of plant, called ‘Annona
senegalensis’ and its constituents. Bioassay guided fractionation led
to the isolation of four metabolites, (+)-catechin (1), (−)-anonaine (2),
(−)-asimilobine (3) and (+)-nornantenine (4). This is the first report on the
isolation of compounds 1, 3 and 4 from this plant. Compounds 2 and 4
showed good activity, whereas 1 and 3 displayed weak inhibition against
Streptococcus mutans (ATCC 25175). The results showed that compound
2 and 3 showed significant activity with a minimum inhibition
concentration (MIC) of 0.12 and 0.25 mg/mL, respectively. The present
study reports for the first time the antibacterial activity of the extract
of A. senegalensis and its constituents. As S. mutans is a rather resistant
bacteria, the MIC obtained during the present study is significant.
Antibacterial potential of alkaloids isolated from Annona senegalensis.The South African Agency for Science and Technology Advancement [grant number N00117], the University of Pretoria and the National Research Foundation (NRF).http://www.tandfonline.com/loi/gnpl202017-12-31hb2017Plant Production and Soil Scienc
Antiproliferative Activity of Buddleja saligna (Willd.) against Melanoma and In Vivo Modulation of Angiogenesis
Funding Information: This research was funded by the University of Pretoria, the National Research Foundation-DAAD (SFD13080220333), the Department of Science and Innovation (DST/CON 0059/2019), the Innovation Hub, L’Oréal-UNESCO and FCT-MCTES (UIDP/04378/2020 and UIDB/04378/2020). Publisher Copyright: © 2022 by the authors.Melanoma cells secrete pro-angiogenic factors, which stimulates growth, proliferation and metastasis, and therefore are key therapeutic targets. Buddleja saligna (BS), and an isolated triterpenoid mixture (DT-BS-01) showed a fifty percent inhibitory concentration (IC50) of 33.80 ± 1.02 and 5.45 ± 0.19 µg/mL, respectively, against melanoma cells (UCT-MEL-1) with selectivity index (SI) values of 1.64 and 5.06 compared to keratinocytes (HaCat). Cyclooxygenase-2 (COX-2) inhibition was observed with IC50 values of 35.06 ± 2.96 (BS) and 26.40 ± 4.19 µg/mL (DT-BS-01). BS (30 µg/mL) significantly inhibited interleukin (IL)-6 (83.26 ± 17.60%) and IL-8 (100 ± 0.2%) production, whereas DT-BS-01 (5 µg/mL) showed 51.07 ± 2.83 (IL-6) and 0 ± 6.7% (IL-8) inhibition. Significant vascular endothelial growth factor (VEGF) inhibition, by 15.84 ± 4.54 and 12.21 ± 3.48%, respectively, was observed. In the ex ovo chick embryo yolk sac membrane assay (YSM), BS (15 µg/egg) significantly reduced new blood vessel formation, with 53.34 ± 11.64% newly formed vessels. Silver and palladium BS nanoparticles displayed noteworthy SI values. This is the first report on the significant anti-angiogenic activity of BS and DT-BS-01 and should be considered for preclinical trials as there are currently no US Food and Drug Administration (FDA) approved drugs to inhibit angiogenesis in melanoma.publishersversionpublishe