Medicinal plants have many traditional claims including the treatment of ailments of infectious origin. In the evaluation of traditional claims, scientific research is important. The objective of the study was to determine the presence of antibacterial activity in the crude extracts of some of the commonly used medicinal plants in Malaysia, Andrographis paniculata, Vitex negundo, Morinda citrifolia, Piper sarmentosum, and Centella asiatica. In this preliminary investigation, the leaves were used and the crude extracts were subjected to screening against five strains of bacteria species, Methicillin Resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, using standard protocol of Disc Diffusion Method (DDM). The antibacterial activities were assessed by the presence or absence of inhibition zones and MIC values. M. citrifolia, P. sarmentosum and C. asiatica methanol extract and A. paniculata (water extract) have potential antibacterial activities to both gram positive S. aureus and Methicillin Resistant S. aureus (MRSA). None of the five plant extracts tested showed antibacterial activities to gram negative E. coli and K. pneumoniae, except for A. paniculata and P. sarmentosum which showed activity towards P. aeruginosa. A. paniculata being the most potent at MIC of 2 g/disc. This finding forms a basis for further studies on screening of local medicinal plant extracts for antibacteria properties.
BACKGROUND: Various extracts of Centella asiatica (Apiaceae) and its active constituent, asiaticoside, have been reported to possess wound healing property when assessed using various in vivo and in vitro models. In an attempt to develop a formulation with accelerated wound healing effect, the present study was performed to examine in vivo efficacy of asiaticoside-rich hydrogel formulation in rabbits.
METHODS: Asiaticoside-rich fraction was prepared from C. asiatica aerial part and then incorporated into polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogel. The hydrogel was subjected to wound healing investigation using the in vivo incision model.
RESULTS: The results obtained demonstrated that: i) the hydrogel formulation did not cause any signs of irritation on the rabbits' skin and; ii) enhanced wound healing 15% faster than the commercial cream and > 40% faster than the untreated wounds. The skin healing process was seen in all wounds marked by formation of a thick epithelial layer, keratin, and moderate formation of granulation tissues, fibroblasts and collagen with no fibrinoid necrosis detected.
CONCLUSION: The asiaticoside-rich hydrogel developed using the freeze-thaw method was effective in accelerating wound healing in rabbits.
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10-6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.
Centella asiatica is a commonly used medicinal plant in Malaysia. As heavy metal accumulation in medicinal plants which are highly consumed by human is a serious issue, thus the assessment of heavy metals in C. asiatica is important for the safety of consumers. In this study, the heavy metal accumulation in C. asiatica and the potential health risks were investigated. Samples of C. asiatica and surface soils were collected from nine different sites around Peninsular Malaysia. The concentration of six heavy metals namely Cd, Cu, Ni, Fe, Pb and Zn were determined by air-acetylene flame atomic absorption spectrophotometer (AAS). The degree of anthropogenic influence was assessed by calculating the enrichment factor (EF) and index of geoaccumulation (Igeo). The heavy metal uptake into the plant was estimated through the calculation of translocation factor (TF), bioconcentration factor (BCF) and correlation study. Estimated daily intakes (EDI) and target hazard quotients (THQ) were used to determine the potential health risk of consuming C. asiatica. The results showed that the overall surface soil was polluted by Cd, Cu and Pb, while the uptake of Zn and Ni by the plants was high. The value of EDI and THQ showed that the potential of Pb toxicity in C. asiatica was high as well. As heavy metal accumulation was confirmed in C. asiatica, daily consumption of the plant derived from polluted sites in Malaysia was not recommended.
Microfungi isolated from Malay traditional vegetables such as Centella asiatica, Cosmos caudatus, Oenanthe javanica, Persicaria odorata and Psophocarpus tetragonolobus are well diverse. A total of 40 isolates of the fungi were identified and classified into four genera such as Aspergillus, Fusarium, Penicillium and Trichoderma. Five species of Fusarium were morphologically identified as F. oxysporum, F. semitectum, F. proliferatum, F. solani and F. konzum. Three species of Aspergillus were identified as A. niger, A. fumigatus and A. flavus. The highest number of microfungi was isolated from Cosmos caudatus (12 isolates), followed by Persicaria odorata (9 isolates), Oenanthe javanica (8 isolates), Centella asiatica (6 isolates) and Psophocarpus tetragonolobus (5 isolates). Four isolates of Fusarium species were able to produce moniliformin (MON) and five isolates were able to produce fumonisin B1 (FB1). This is the first report on diversity of microfungi associated with some Malay traditional vegetables.
Sepsis refers to organ failure due to uncontrolled body immune responses towards infection. The systemic inflammatory response triggered by pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS) from Gram-negative bacteria, is accompanied by the release of various proinflammatory mediators that can lead to organ damage. The progression to septic shock is even more life-threatening due to hypotension. Thus, sepsis is a leading cause of death and morbidity globally. However, current therapies are mainly symptomatic treatment and rely on the use of antibiotics. The lack of a specific treatment demands exploration of new drugs. Malaysian herbal plants have a long history of usage for medicinal purposes. A total of 64 Malaysian plants commonly used in the herbal industry have been published in Malaysian Herbal Monograph 2015 and Globinmed website (http://www.globinmed.com/). An extensive bibliographic search in databases such as PubMed, ScienceDirect, and Scopus revealed that seven of these plants have antisepsis properties, as evidenced by the therapeutic effect of their extracts or isolated compounds against sepsis-associated inflammatory responses or conditions in in vitro or/and in vivo studies. These include Andrographis paniculata, Zingiber officinale, Curcuma longa, Piper nigrum, Syzygium aromaticum, Momordica charantia, and Centella asiatica. Among these, Z. officinale is the most widely studied plant and seems to have the highest potential for future therapeutic applications in sepsis. Although both extracts as well as active constituents from these herbal plants have demonstrated potential antisepsis activity, the activity might be primarily contributed by the active constituent(s) from each of these plants, which are andrographolide (A. paniculata), 6-gingerol and zingerone (Z. officinale), curcumin (C. longa), piperine and pellitorine (P. nigrum), biflorin (S. aromaticum), and asiaticoside, asiatic acid, and madecassoside (C. asiatica). These active constituents have shown great antisepsis effects, and further investigations into their clinical therapeutic potential may be worthwhile.
The potential of Moringa oleifera Lam. (Moringaceae) and Centella asiatica (L.) Urban (Apiaceae) extracts (TGT-PRIMAAGE) in slowing the decline of memory and learning activity was investigated using D-galactose-induced ageing rat model. The extracts were profiled and standardised based on markers identified using LC/MS-QTOF. Toxicity study of the extract was done, and the rat did not show any sign of toxicity. The extract was orally administered to the rat and dose dependent (100, 500 and 1000 mg/kg) efficacy were investigated. The rats were subjected to Morris Water Maze whereby 3 parameters were studied (number of entry to platform, latency and novel object recognition). Plasma was collected for the determination of catalase (CAT) activity and levels of malondialdehyde (MDA) and advanced glycation end products (AGEs). The activity of acetylcholinesterase (AChE), level of acetylcholine (ACh) and lipid peroxidation (LPO) were measured using the brain lysates. Significant improvement (p < 0.05) was seen in the memory and learning abilities in the aged rats that received medium and high dose of TGT-PRIMAAGE, and tocotrienol. Rats treated with TGT-PRIMAAGE had also shown improved CAT activity and resulted in reduced LPO. The level of ACh was found increased in parallel with the reduced AChE activity. The capabilities of learning and memory of the TGT-PRIMAAGE treated rats were enhanced via inhibition of AChE activity and subsequently increased level of ACh.
The first objective of this study was to provide data of arsenic (As) levels in Peninsular Malaysia based on soil samples and accumulation of As in Centella asiatica collected from 12 sampling sites in Peninsular Malaysia. The second objective was to assess the accumulation of As in transplanted C. asiatica between control and semi-polluted or polluted sites. Four sites were selected which were UPM (clean site), Balakong (semi-polluted site), Seri Kembangan (semi-polluted site) and Juru (polluted site). The As concentrations of plant and soil samples were determined by Instrumental Neutron Activation Analysis. The As levels ranged from 9.38 to 57.05 μg/g dw in soils, 0.21 to 4.33 μg/g dw in leaves, 0.18 to 1.83 μg/g dw in stems and 1.32-20.76 μg/g dw in roots. All sampling sites had As levels exceeding the CCME guideline (12 μg/g dw) except for Kelantan, P. Pauh, and Senawang with P. Klang having the highest As in soil (57.05 μg/g dw). In C. asiatica, As accumulation was highest in roots followed by leaves and stems. When the As level in soils were higher, the uptake of As in plants would also be increased. After the transplantation of plants to semi-polluted and polluted sites for 3 weeks, all concentration factors were greater than 50 % of the initial As level. The elimination factor was around 39 % when the plants were transplanted back to the clean sites for 3 weeks. The findings of the present study indicated that the leaves, stems and roots of C. asiatica are ideal biomonitors of As contamination. The present data results the most comprehensive data obtained on As levels in Malaysia.
Centella asiatica is widely used as a medicinal plant in Malaysia and other parts of the world. In the present study, the growth and uptake of heavy metal by C. asiatica were determined based on the plant exposure to different treatment of metal-contaminated soils under laboratory conditions. Heavy metals uptake in different parts of the plants namely roots, stems and leaves were determined. In general, it was found that the metal uptake capacity followed the order: roots > stems > leaves. Since a close positive relationship was established between the concentrations of metal accumulated in different parts of the plant and the metal levels in the most contaminated soil, C. asiatica has the potential of being used as a biomonitoring plant for heavy metal pollution in the polluted soils.
The synergistic antioxidant effects of ethanolic extracts of Centella asiatica (CE), and α-tocopherol have been studied. The types of interactions exhibited by CE and α-tocopherol combined at different ratios were measured using three assays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical-scavenging capacity, the β-carotene bleaching system and liposome peroxidation assays. Fixed-fraction isobolographic analysis was used to detect any inducement of the antioxidant activity compared with the individual activities of CE and α-tocopherol. Of all synergistic combinations of CE and α-tocopherol, only fraction 2/3 showed the synergistic combination that fits well in three different assays and can be explained by the regeneration of α-tocopherol by CE despite the interaction effect of β-carotene present in the analytical assay. This phenomenon involved complex interactions between CE and α-tocopherol to exhibit different degrees of interactions that eventually increased antioxidant activity.
This study was carried out by using Centella asiatica grown using a hydroponic system under laboratory conditions to study synergistic and antagonistic effects of Zn bioaccumulation with added Pb and the changes in antioxidant activities in leaves and roots of C. asiatica. The antioxidant activities included superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and guaiacol peroxidase (GPX). The treatments Zn (2 ppm) + Pb (0.4 ppm) and Zn (4 ppm) + Pb (0.6 ppm) increased the accumulation of Zn in leaves by 14.06 and 16.84%, respectively, but decreased by 7.36% uptake in roots (Zn 4 ppm + Pb 0.6 ppm). This showed that Pb and Zn acted synergistically to Zn accumulation in leaves but antagonistically in roots. CAT and SOD activities in leaves were increased when Zn was added together with Pb. In roots, CAT, APX and SOD activities were increased but GPX was decreased. Owing to their sensitivities to Zn with Pb, SOD and CAT could be used as biomarkers to monitor the toxicity of Pb and Zn exposure in the leaves and roots of C. asiatica.
In this study, Centella asiatica and surface soils were collected from 12 sampling sites in Peninsular Malaysia, and the barium (Ba) concentrations were determined. The Ba concentration [µg/g dry weight (dw)] was 63.72 to 382.01 µg/g in soils while in C. asiatica, Ba concentrations ranged from 5.05 to 21.88 µg/g for roots, 3.31 to 11.22 µg/g for leaves and 2.37 to 6.14 µg/g for stems. In C. asiatica, Ba accumulation was found to be the highest in roots followed by leaves and stems. The correlation coefficients (r) of Ba between plants and soils were found to be significantly positively correlated, with the highest correlation being between roots-soils (r=0.922, p
Salmonella has been reported to be presence both in raw and processed foods worldwide. In this study, the prevalence, quantification and antibiotic susceptibility of Salmonella isolated from raw vegetables or locally known as ulam such as asiatic pennywort (Centella asiatica (L) Urb), water dropwort (Oenanthe javanica (Blume) DC), long bean (Vigna sinensis EndL), and winged bean (Psophocarpus tetragonolobus (L) DC) obtained from retail markets in Selangor, Malaysia were carried out. From 96 samples tested, the overall prevalence of Salmonella spp. was 97.9%, Salmonella Enteritidis was 54.2% and Salmonella Typhimurium was 82.3% respectively. Samples were contaminated with Salmonella ranging from < 3 to 2400 MPN/g. Salmonella Enteritidis and Salmonella Typhimurium isolates obtained from the raw vegetables (ulam) were found to exhibit high resistance against ampicillin (100%), erythromycin (100%), amoxicillin/clavunic acid (81.3%), cephalothin (75%), streptomycin (50%) and ciprofloxacin (50%). All Salmonella isolates showed multi drug resistant (MDR) profile with each isolate being resistant to 3 or more antibiotics. The multiple antibiotic resistance (MAR) index of Salmonella isolates ranged from 0.27 to 0.55 for Salmonella Enteritidis and 0.27 to 0.82 for Salmonella Typhimurium. The presence of Salmonella on raw vegetables (ulam) and high antibiotic resistance isolates indicated that raw vegetables could be contaminated and thus imposes possible health risk to local consumers.
Centella asiatica is a reputed medicinal plant used in the treatment of various skin diseases in the Indian system of medicine. The objective of the study presented in this article was to evaluate the wound-healing potential of the ethanolic extract of the plant in both normal and dexamethasone-suppressed wound healing. The study was done on Wistar albino rats using incision, excision, and dead space wounds models. The extract of C asiatica significantly increased the wound breaking strength in incision wound model compared to controls (P < .001). The extract-treated wounds were found to epithelize faster, and the rate of wound contraction was significantly increased as compared to control wounds (P < .001). Wet and dry granulation tissue weights, granulation tissue breaking strength, and hydroxyproline content in a dead space wound model also increased at statistically significant levels as shown. The extract of the leaves had the effect of attenuating the known effects of dexamethasone healing in all wound models (P < .001, P < .05). The results indicated that the leaf extract promotes wound healing significantly and is able to overcome the wound-healing suppressing action of dexamethasone in a rat model. These observations were supported by histology findings.
Objective. To investigate the potential effect of Hydrocotyle sibthorpioides Lam. (H. sibthorpioides) extracts against in vitro dengue viral replication. Methods. The cytotoxicity of H. sibthorpioides was evaluated using a cell viability assay. Cells were pre- and posttreated with water and methanol extracts of H. sibthorpioides, and the viral inhibitory effect was investigated by observing the morphological changes, which were further confirmed by plaque assay. Results. The methanolic extract cytotoxicity was higher in Vero and C6/36 cells than the cytotoxicity of the water extract. Preincubation of the cells with H. sibthorpioides extract showed nonexistent to mild prophylactic effects. The posttreatment of Vero cells with H. sibthorpioides methanolic extract presented higher antidengue activities when compared with the water extract. Surprisingly, posttreatment of C6/36 cells resulted in an enhancement of viral replication. Conclusion. H. sibthorpioides had variable effects on dengue viral replication, depending on the treatment, cell lines, and solvent types. This study provides important novel insights on the phytomedicinal properties of H. sibthorpioides extracts on dengue virus.
Centella asiatica is claimed to have a neuroprotective effect; however, its ability to protect the cerebrum against damage in diabetes has never been identified. The aims were to identify the possibility that C. asiatica ameliorates inflammation, oxidative stress, and apoptosis in the cerebrum in diabetes. C. asiatica leave aqueous extract (C. asiatica) (50, 100, and 200 mg/kg/b.w.) were given to diabetic rats for 28 days. Changes in rats' body weight, food and water intakes, and insulin and FBG levels were monitored. Following sacrificed, cerebrum was harvested and subjected for histological, biochemical, and molecular biological analyses. The results revealed treatment with C. asiatica was able to ameliorate the loss in body weight, the increase in food and water intakes, the decrease in insulin, and the increase in FBG levels in diabetic rats. Additionally, histopathological changes in the cerebrum and levels of p38, ERK, JNK, cytosolic Nrf2, Keap-1, LPO, RAGE, and AGE levels decreased; however, PI3K, AKT, IR, IRS, GLUT-1, nuclear Nrf2, Nqo-1, Ho-1, and anti-oxidative enzymes (SOD, CAT, and GPx) levels increased in diabetic rats receiving C. asiatica. Furthermore, C. asiatica treatment also caused cerebral inflammation and apoptosis to decrease as indicated by decreased inflammatory markers (cytosolic NF-κB p65, p-Ikkβ, Ikkβ, iNOS, COX-2, TNF-α, IL-6, and IL-1β), decreased pro-apoptosis markers (Casp-3, 9, and Bax), but increased anti-apoptosis marker, Bcl-2. Activity level of Na+/K+, Mg2+, and Ca2+-ATPases in the cerebrum also increased by C. asiatica treatment. Conclusions: C. asiatica treatment helps to prevent cerebral damage and maintain near normal cerebral function in diabetes.
Diabetes mellitus has been reported to affect functions of the hippocampus. We hypothesized that Centella asiatica, a herb traditionally being used to improve memory, prevents diabetes-related hippocampal dysfunction. Therefore, the aim of this study was to investigate the protective role of C. asiatica on the hippocampus in diabetes. Methods. Streptozotocin- (STZ-) induced adult male diabetic rats received 100 and 200 mg/kg/day body weight (b.w) C. asiatica leaf aqueous extract for four consecutive weeks. Following sacrifice, hippocampus was removed and hippocampal tissue homogenates were analyzed for Na(+)/K(+)-, Ca(2+)- and Mg(2+)-ATPases activity levels. Levels of the markers of inflammation (tumor necrosis factor, TNF-α; interleukin, IL-6; and interleukin, IL-1β) and oxidative stress (lipid peroxidation product: LPO, superoxide dismutase: SOD, catalase: CAT, and glutathione peroxidase: GPx) were determined. The hippocampal sections were visualized for histopathological changes. Results. Administration of C. asiatica leaf aqueous extract to diabetic rats maintained near normal ATPases activity levels and prevents the increase in the levels of inflammatory and oxidative stress markers in the hippocampus. Lesser signs of histopathological changes were observed in the hippocampus of C. asiatica leaf aqueous extract treated diabetic rats. Conclusions. C. asiatica leaf protects the hippocampus against diabetes-induced dysfunction which could help to preserve memory in this condition.
Moringa oleifera Lam. and Centella asiatica (L.) Urb. leaves have been previously reported to exhibit antioxidant activity. The objective of the present study is to determine the in vitro antioxidant activity of the combined extracts of M. oleifera and C. asiatica (TGT-PRIMAAGE) and its effect on hydrogen peroxide (H 2O2)-induced oxidative stress in human dermal fibroblasts. TGTPRIMAAGE acted on the mechanism of hydrogen transfer as it showed scavenging activity in the DPPH assay. This is due to the presence of phenolics and flavonoids in TGT-PRIMAAGE. TGT-PRIMAAGE effectively reduced cellular generation of reactive oxygen species induced by H O2. The activities of superoxide dismutase and catalase were also increased in cells treated with TGT-PRIMAAGE. 2 Treatment with TGT-PRIMAAGE showed significant reduction (P < 0.05) in the number of senescent cells. Significant reduction (P < 0.05) of malondialdehyde was also seen in cells treated with TGT-PRIMAAGE. The p53 protein level was reduced in TGT-PRIMAAGEtreated cells, which indicates its potential in protecting the cells from oxidative stress induced by H2O2.
Centella asiatica is a traditional herbal medicine that has been shown to have pharmacological effect on skin wound healing, and could be potential therapeutic agent for corneal epithelial wound healing.
The molecular pathways underlying the diverse biological activity of the triterpeniod compounds isolated from the tropical medicinal plant Centella asiatica were studied with gene microarrays and real-time reverse transcription polymerase chain reaction (real-time RT-PCR) to quantify the expression of 1053 human genes in human fibroblasts. Fibroblast cells grown in culture were used as a model system to evaluate the stimulation of wound healing by titrated extract from Centella asiatica (TECA) as well as by the four principal triterpenoid components of Centella. TECA treatment effects the expression of genes involved in angiogenesis and the remodeling of extracellular matrix, as well as diverse growth factor genes. The extent of expression change of TNFAIP6, an extracellular hyaluronan binding protein, was found to be largely dose-dependent, to respond most strongly to the free acids asiatic acid and madecassic acid, and to increase in expression over 48 hours of treatment. These results show that Centella triterpenes evoke a gene-expression response consistent with their prevailing medical uses in the treatment of connective tissue disorders such as wound healing and microangiopathy. The identification of genes modulated by these compounds provides the basis for a molecular understanding of Centella's bioactivity, and opportunities for the quantitative correlation of this activity with clinical effectiveness at a molecular level.