Wound healing properties and kill kinetics of Clerodendron splendens G. Don, a Ghanaian wound healing plant

GC/MS Composition and Resistance Modulatory Inhibitory Activities of Three Extracts of Lemongrass: Citral Modulates the Activities of Five Antibiotics at Sub-Inhibitory Concentrations on Methicillin-Resistant Staphylococcus aureus

We investigated whether three extractable fractions of lemongrass (Cymbopogon citratus): aqueous and ethanol extracts and lemongrass essential oil exhibited any antimicrobial resistance modulatory effects if used in combination with selected antibiotics ampicillin, tetracycline, streptomycin, cefloxacin and amoxicillin on methicillin-resistant Staphylococcus aureus (MRSA). MRSA growth inhibition (zones of inhibition) was greatest for the lemongrass oil at concentrations of 1, 2, 5, 10 and 20 % (wt/vol). The MIC for lemongrass oil was 0.5 mg/mL, while it was 4 mg/mL for both the aqueous and ethanol extracts. Evaluation of extracts for antibacterial resistance modifying activities when used in combination with either of the five antibiotics at sub-inhibitory concentrations, showed that lemongrass oil highly potentiated the activities of three antibiotics; amoxicillin, streptomycin and tetracycline. The ethanol extract enhanced the activity of tetracycline and ampicillin, while the aqueous extract only increased the activity of tetracycline against MRSA. The activity of cefloxacin with the extracts was either indifferent. Analysis of the lemongrass oil by GC/MS showed the prominence of three compounds: the two isomers neral and geranial of citral and, the acetate geranyl acetate, which together made up 94 % of the composition. The compounds were also observed in the ethanol and water extracts but to a lesser extent when analyzed by HPLC-UV (λ 233 nm). Our study confirms the antibacterial properties of the extracts especially, lemongrass oil. It also demonstrates that lemongrass oil potentiates the activities of three antibiotics against the biofilm-forming MRSA. This biocidal, anti-biofilm disruption and antibiotic potentiating abilities are mainly attributable to citral and geranyl acetate, further evidence of lemongrass oil as a very useful source of phytochemicals, especially citral for the fight against antibiotic resistance.

Recent technological advances in the management of chronic wounds: A literature review

Background

Wound treatment comprises a substantial portion of the healthcare budgets in developed countries. Studies suggest that about 50% of patients admitted to hospitals have wounds, while 1%−2% of the general population in the developed world suffers from chronic wounds. Chronic wounds fail to repair themselves within the expected period of 30 days. Technologies have been developed to address challenges encountered during wound care with the aim of alleviating pain, promoting healing, or controlling wound infections.

Objective

The objective of this study was to explore the technological improvements that have been made in this field over time.

Methods

To gain insight into the future of wound management, a systematic review of literature on the subject was conducted in scientific databases (PubMed, Scopus, Web of Science, Medline, and Clinical Trials).

Results and Discussion

Results indicate that wound dressings have evolved from the traditional cotton gauze to composite materials embedded with appropriate ingredients such as metal‐based nanoparticles. Studies on biodegradable dressing materials are also underway to explore their applicability in dressing large and irregular wounds. On the other hand, conventional drugs and traditional formulations for the management of pain, inflammation, infections, and accelerating healing have been developed. However, more research needs to be carried out to address the issue of microbial resistance to drugs. Drugs for managing other ailments also need to be designed in such a way that they can augment wound healing. In addition, it has been demonstrated that a coordinated integration of conventional and traditional medicine can produce laudable results in chronic wound management.

Conclusion

Accordingly, collaborative efforts and ingenuity of all players in the field can accelerate technological advances in the wound care market to the benefit of the patients.

Wounds affect about 50% of patients admitted to hospitals.

Technologies have been developed including biodegradable dressing materials to address underlying challenges.

Technological advancement, rising incidences of chronic wounds, growing government support, and a rising elderly population will drive wound market growth.

A careful combination of recent research outputs can greatly change wound care technologies.

This review highlights the recent research advances and opportunities in the wound care field.

The future lies in biodegradable dressing materials, probably embedded with selected nanoparticles and which shall be combined in predetermined ratios.

Evaluation of anticancer activity of Clerodendrum viscosum leaves against breast carcinoma

INTRODUCTION

The use of natural resources as medicines for cancer therapies has been described throughout history in the form of traditional medicines. However, many resources are still unidentified for their potent biological activities. Clerodendrum viscosum is a hill glory bower reported as a remedy against oxidative stress, skin diseases, and intestinal infections.

MATERIALS AND METHODS

We have collected the C. viscosum leaves and used for the preparation of 70% methanolic extract (CVLME). Then, CVLME has been confirmed for anticancer properties on various cancer cell lines by evaluating cytotoxicity, cell cycle analysis, induction of ROS and apoptosis, and nuclear fragmentation. Further, the phytochemical analysis of CVLME was evaluated through high-performance liquid chromatography.

RESULTS

Cell proliferation assay revealed the selective cytotoxicity of CVLME against breast cancer cell line (MCF-7). The FACS-based cell cycle analysis showed increased subG1 (apoptosis) population dose dependently. Further, the apoptosis-inducing effect of CVLME was confirmed by annexin staining. Flow cytometry and confocal microscopy revealed the selective ROS generation upon CVLME treatment. The confocal-based morphological study also revealed condensed and fragmented nuclear structure in CVLME-treated MCF-7 cells. Phytochemical investigations further indicated the presence of tannic acid, catechin, rutin, and reserpine which might be the reason for the anticancer activity of CVLME.

CONCLUSION

The above-combined results revealed the anticancer effect of CVLME, which may be due to the selective induction of ROS in breast carcinoma.

Reproducibility challenges in the search for antibacterial compounds from nature

BACKGROUND

Reproducibility of reported antibacterial activities of plant extracts has long remained questionable. Although plant-related factors should be well considered in serious pharmacognostic research, they are often not addressed in many research papers. Here we highlight the challenges in reproducing antibacterial activities of plant extracts.

METHODS

Plants with reported antibacterial activities of interest were obtained from a literature review. Antibacterial activities against Escherichia coli and Klebsiella pneumoniae were tested using extracts' solutions in 10% DMSO and acetone. Compositions of working solutions from both solvents were established using LC-MS analysis. Moreover, the availability of details likely to affect reproducibility was evaluated in articles which reported antibacterial activities of studied plants.

RESULTS

Inhibition of bacterial growth at MIC of 256-1024 μg/mL was observed in only 15.4% of identical plant species. These values were 4-16-fold higher than those reported earlier. Further, 18.2% of related plant species had MICs of 128-256 μg/mL. Besides, 29.2% and 95.8% of the extracts were soluble to sparingly soluble in 10% DMSO and acetone, respectively. Extracts' solutions in both solvents showed similar qualitative compositions, with differing quantities of corresponding phytochemicals. Details regarding seasons and growth state at collection were missing in 65% and 95% of evaluated articles, respectively. Likewise, solvents used to dissolve the extracts were lacking in 30% of the articles, whereas 40% of them used unidentified bacterial isolates.

CONCLUSION

Reproducibility of previously reported activities from plants' extracts is a multi-factorial aspect. Thus, collective approaches are necessary in addressing the highlighted challenges.

Chemical Composition of Moringa oleifera Ethyl Acetate Fraction and Its Biological Activity in Diabetic Human Dermal Fibroblasts

Background:

Moringa oleifera (MO), commonly known as the drumstick tree, is used in folklore medicine for the treatment of skin disease.

Objective:

The objective of this study is to evaluate the ethyl acetate (EtOAc) fraction of MO leaves for in vitro antibacterial, antioxidant, and wound healing activities and conduct gas chromatography-mass spectrometry (GC-MS) analysis.

Materials and Methods:

Antibacterial activity was evaluated against six Gram-positive bacteria and 10 Gram-negative bacteria by disc diffusion method. Free radical scavenging activity was assessed by 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radical hydrogen peroxide scavenging and total phenolic content (TPC). Wound healing efficiency was studied using cell viability, proliferation, and scratch assays in diabetic human dermal fibroblast (HDF-D) cells.

Results:

The EtOAc fraction showed moderate activity against all bacterial strains tested, and the maximum inhibition zone was observed against Streptococcus pyogenes (30 mm in diameter). The fraction showed higher sensitivity to Gram-positive strains than Gram-negative strains. In the quantitative analysis of antioxidant content, the EtOAc fraction was found to have a TPC of 65.81 ± 0.01. The DPPH scavenging activity and the hydrogen peroxide assay were correlated with the TPC value, with IC₅₀ values of 18.21 ± 0.06 and 59.22 ± 0.04, respectively. The wound healing experiment revealed a significant enhancement of cell proliferation and migration of HDF-D cells. GC-MS analysis confirmed the presence of 17 bioactive constituents that may be the principal factors in the significant antibacterial, antioxidant, and wound healing activity.

Conclusion:

The EtOAc fraction of MO leaves possesses remarkable wound healing properties, which can be attributed to the antibacterial and antioxidant activities of the fraction.

SUMMARY

Moringa oleifera (MO) leaf ethyl acetate (EtOAc) fraction possesses antibacterial activities toward Gram-positive bacteria such as Streptococcus pyogenes, Streptococcus faecalis, Bacillus subtilis, Bacillus cereus and Staphylococcus aureus, and Gram-negative bacteria such as Proteus mirabilis and Salmonella typhimurium

MO leaf EtOAc fraction contained the phenolic content of 65.81 ± 0.01 and flavonoid content of 37.1 ± 0.03, respectively. In addition, the fraction contained 17 bioactive constituents associated with the antibacterial, antioxidant, and wound healing properties that were identified using gas chromatography-mass spectrometry analysis

MO leaf EtOAc fraction supports wound closure rate about 80% for treatments when compared with control group.

Abbreviations used: MO: Moringa oleifera; EtOAc: Ethyl acetate; GC-MS: Gas Chromatography-Mass Spectrometry; HDF-D: Diabetic Human Dermal Fibroblast cells.

In vitro Antioxidant and Antiproliferative Activities of Various Solvent Fractions from Clerodendrum viscosum Leaves

Background:

Free radicals such as reactive oxygen and nitrogen species, generated in the body, play an important role in the fulfillment of various physiological functions but their imbalance in the body lead to cellular injury and various clinical disorders such as cancer, neurodegenaration, and inflammation.

Objective:

The objective of this study is to fight this problem, natural antioxidant from plants can be considered as possible protective agents against various diseases such as cancer which might also modify the redox microenvironment to reduce the genetic instability. This study was designed to evaluate the antioxidant and antiproliferative potential of Clerodendrum viscosum fractions against various carcinomas.

Materials and Methods:

In this present study, 70% methanolic extract of C. viscosum leaves have been fractionated to obtain hexane, chloroform, ethyl acetate, butanol, and water fractions, which were tested for their antioxidant and anticancer properties.

Results:

It was observed that chloroform and ethyl acetate fractions showed good free radical scavenging properties as well as inhibited the proliferation of human lung cancer (A459), breast (MCF-7), and brain (U87) cells. Moreover, they arrested the cell cycle at G2/M phase of breast and brain cancer. These inhibitory effects were further confirmed by bromodeoxyuridine uptake imaging. Phytochemical investigations further indicate the presence of tannic acid, quercetin, ellagic caid, gallic acid, reserpine, and methyl gallate which might be the reason for these fractions’ antioxidant and antiproliferative activities.

Conclusion:

Clerodendrum viscosum leaf chloroform and Clerodendrum viscosum leaf ethyl acetate fractions from C. viscosum showed good reactive oxygen species and reactive nitrogen species scavenging potential. Both the fractions arrested cell cycle at G2/M phase in MCF-7 and U87 cells which lead to induce apoptosis.

SUMMARY

Crude extract of Clerodendrum viscosum leaves was fractionated using different solvents

Among them, chloroform and ethyl acetate fractions exhibited excellent free radical scavenging properties

The same fractions inhibited the proliferation of human lung cancer (A459), breast (MCF-7), and brain (U87) cells

Chloroform and ethyl acetate fractions arrested the cell cycle at G2/M phase of breast and brain cancer

Phytochemical investigations further indicate the presence of several bioactive principles present in them.

Abbreviations used: CVLME: Clerodendrum viscosum leaf methanolic extract; CVLH: Clerodendrum viscosum leaf hexane; CVLC: Clerodendrum viscosum leaf chloroform; CVLE: Clerodendrum viscosum leaf ethyl acetate; CVLB: Clerodendrum viscosum leaf butanol; CVLW: Clerodendrum viscosum leaf water; BrdU: Bromodeoxyuridine; WST-1: Water soluble tetrazolium salt.

Phenolic Compounds and Its Bioavailability: In Vitro Bioactive Compounds or Health Promoters?

Botanical preparations present a widespread and secular history of use. In fact, natural matrices possess a rich pool of phytochemicals, with promising biological effects. Among them, phenolic compounds have revealed to confer very important attributes to improve the well-being and longevity of worldwide population. Numerous in vitro studies have been carried out evaluating the wide spectrum of bioactivities of phenolic compounds, including its health effects, but through in vivo experiments some of these previous results cannot be properly confirmed, and considerable variations are observed. Pharmacokinetic parameters, including the assessment of bioavailability and bioefficacy of phenolic compounds, still continue to be largely investigated and considered a great hot topic among the food science and technology researchers. Thus, based on these crucial aspects, this chapter aims to provide an extensive approach about the question of the bioavailability of phenolic compounds, describing its biosynthetic routes and related mechanisms of action; to focus on the current facts and existing controversies, highlighting the importance of in vivo studies and the impact of phenolic compounds on the quality of life and longevity.

STUDIES ON WOUND HEALING ACTIVITY OF SOME EUPHORBIA SPECIES ON EXPERIMENTAL RATS

BACKGROUND

Plants of Euphorbiaceae are used in folkloric medicines in variety of ailments and well known for chemical diversity of their isoprenoid constituents. This study was carried out to explore the preliminary wound healing potential of four Euphorbia species (E. consorbina 1, E. consorbina 2, E. inarticulata, E. balsamifera and E. schimperi).

MATERIALS AND METHODS

Excision wound surface of the animals were topically treated with ethyl acetate and methanol extracts of plants at a dose of 400 mg/kg body weight for twenty days. Povidone-iodine ointment was used as a reference drug. Wound contraction measurement and period of epithelialization were used to assess the effect of plants extracts on wound repairing.

RESULTS

The groups treated with methanol extracts of E. balsamifera and E. schimperi showed profound effects, high rate of wound contraction (100%) and decrease in epithelization period 19.00±0.40 and 18.50±0.64 respectively, followed by methanol extracts of E. consorbina 2, ethyl acetate extract of E. inarticulata and ethyl acetate extracts of E. consorbina 2 which showed significant (P <0.001) wound contraction and decrease in epithelization period. Conversely ethyl acetate extract of E. consorbina 1, E. balsamifera and E. schimperi and methanol extract of E. Consorbina 1 and E. Inarticulata treated groups was not showing significant wound healing. Methanol extracts of E. balsamifera and E. schimperi were also tested for their safety margin and found safe up to dose of 2000mg/kg body weight.

CONCLUSION

Topical application of methanol extracts of E. balsamifera and E. schimperi have potential wound healing activity which is identical with standard drug Povidone-iodine.

Review: African medicinal plants with wound healing properties

ETHNOPHARMACOLOGICAL RELEVANCE

Wounds of various types including injuries, cuts, pressure, burns, diabetic, gastric and duodenal ulcers continue to have severe socio-economic impact on the cost of health care to patients, family and health care institutions in both developing and developed countries. However, most people in the developing countries, especially Africa, depend on herbal remedies for effective treatment of wounds. Various in vitro and in vivo parameters are used for the evaluation of the functional activity of medicinal plants by using extracts, fractions and isolated compounds. The aim of the review is to identify African medicinal plants with wound healing properties within the last two decades.

MATERIALS AND METHODS

Electronic databases such as PubMed, Scifinder(®) and Google Scholar were used to search and filter for African medicinal plants with wound healing activity. The methods employed in the evaluation of wound healing activity of these African medicinal plants comprise both in vivo and in vitro models. In vivo wound models such as excision, incision, dead space and burn wound model are commonly employed in assessing the rate of wound closure (contraction), tensile strength or breaking strength determination, antioxidant and antimicrobial activities, hydroxyproline content assay and histological investigations including epithelialisation, collagen synthesis, and granulation tissue formation. In in vitro studies, single cell systems are mostly used to study proliferation and differentiation of dermal fibroblasts and keratinocytes by monitoring typical differentiation markers like collagen and keratin.

RESULTS

In this study, 61 plants belonging to 36 families with scientifically demonstrated or reported wound healing properties were reviewed. Various plant parts including leaves, fruits, stem bark and root extracts of the plants are used in the evaluation of plants for wound healing activities.

CONCLUSION

Although, a variety of medicinal plants for wound healing can be found in literature, there is a need for the isolation and characterization of the bioactive compounds responsible for the wound healing properties. Also, cytotoxicity studies should be performed on the promising agents or bioactive fractions or extracts.

In Vivo Anti-Candida Activity of Phenolic Extracts and Compounds: Future Perspectives Focusing on Effective Clinical Interventions

Candida species have increasingly deserved a special attention among the medical community. In spite of the presence of Candida species as a human commensal, alarming rates of local and systemic infections have been observed, varying from moderate to severe impact. Currently available antifungal drugs have progressively lost their effectiveness, pointing urgently the problem of the microorganisms with acquired-resistance. Natural matrices are secularly used for numerous purposes, being inclusive and highly effective as antimicrobials. Increasing evidence gives a particular emphasis to the contribution of phenolic extracts and related individual compounds. In vitro studies clearly confirm their prominent effects, but the confirmation through in vivo studies, including the involved mechanisms of action, is not so much deepened. Therefore, the present report aims to provide extensive knowledge about all these aspects, highlighting the most efficient phytochemical formulations, including therapeutic doses. Further studies need to be incited to deepen knowledge on this area, namely, focused on clinical trials to provide safer and more effective antimicrobials than the current ones.

The immunostimulatory and antimicrobial property of two herbal decoctions used in the management of HIV/AIDS in Ghana

BACKGROUND

HIV/AIDS is a pandemic retarding economic growth and destroying human capital globally. This study therefore investigated the perceived efficacy of Betula alba (BA) and Sutherlandia frutescens (SF) decoctions used in the management of HIV/AIDS in Ghana.

MATERIALS AND METHODS

A study on the records of HIV/AIDS patients attending Habibi Herbal Clinic, Kumasi, Ghana, was conducted to obtain information on the initial viral load presented during their maiden visit and results after treatment with the herbal decoctions. The decoctions were assessed for immunostimulatory property in cyclophosphamide-induced immunosuppressed ICR mice. Total white blood cell count, as well as lymphocyte and neutrophil counts were determined and their effects compared with Levamisole. The decoctions were also screened for antimicrobial activity by the micro dilution method.

RESULTS

The two herbal decoctions used significantly reduced (P ≤ 0.001) the patients' viral loads (47.42 ± 17.28 % to 13.69 ± 12.42 %; n=16). BA (1, 2, and 4 mg/kg) and SF (0.4, 0.8, and 1.6 mg/kg) caused significant increment (P ≤ 0.001) in total WBC and lymphocyte count in mice comparable to that produced by 2.5 mg/kg Levamisole. The decoctions also exhibited antimicrobial activity against gram negative and gram positive bacteria as well as Candida albicans (MIC 0.607 to 3.062 mg/ml). Phytochemicals present in both plants include saponins, terpenoids and coumarins.

CONCLUSION

The Betula alba and Sutherlandia frutescens decoctions have interesting immunostimulatory and antimicrobial properties and hence could be useful in the management of HIV/AIDS and associated opportunistic infections.

Wound healing potential of formulated extract from hibiscus sabdariffa calyx

Wound healing agents support the natural healing process, reduce trauma and likelihood of secondary infections and hasten wound closure. The wound healing activities of water in oil cream of the methanol extract of Hibiscus sabdariffa L. (Malvaceae) was evaluated in rats with superficial skin excision wounds. Antibacterial activities against Pseudomonas aeroginosa, Staphylococcus aureus and Echerichia coli were determined. The total flavonoid content, antioxidant properties and thin layer chromatographic fingerprints of the extract were also evaluated. The extract demonstrated antioxidant properties with a total flavonoid content of 12.30±0.09 mg/g. Six reproducible spots were obtained using methanol:water (95:5) as the mobile phase. The extract showed no antimicrobial activity on the selected microorganisms, which are known to infect and retard wound healing. Creams containing H. sabdariffa extract showed significant (P<0.05) and concentration dependent wound healing activities. There was also evidence of synergism with creams containing a combination of gentamicin and H. sabdariffa extract. This study, thus, provides evidence of the wound healing potentials of the formulated extract of the calyces of H. sabdariffa and synergism when co-formulated with gentamicin.

Immunomodulatory activity of polysaccharides isolated from Clerodendrum splendens: beneficial effects in experimental autoimmune encephalomyelitis

BACKGROUND

Extracts of leaves from Clerodendrum have been used for centuries to treat a variety of medicinal problems in tropical Africa. However, little is known about the high-molecular weight active components conferring therapeutic properties to these extracts.

METHODS

Polysaccharides from the leaves of Clerodendrum splendens were extracted and fractionated by ion exchange and size-exclusion chromatography. Molecular weight determination, sugar analysis, degree of methyl esterification, and other chemical characterization of the fractions were performed. Immunomodulatory activity of the fractions was evaluated by determining their ability to induce monocyte/macrophage nitric oxide (NO), cytokine production, and mitogen-activated protein kinase (MAPK) phosphorylation. Experimental autoimmune encephalomyelitis (EAE) was induced in C57BL/6 mice, and severity of EAE was monitored in mice treated with intraperitoneal (i.p.) injections of the most active polysaccharide fraction. Lymph nodes (LN) and spleen were harvested, and levels of cytokines in supernatants from LN cells and splenocytes challenged with myelin oligodendrocyte glycoprotein peptide were determined.

RESULTS

Fractions containing type II arabinogalactan had potent immunomodulatory activity. Specifically, the high-molecular weight sub-fraction CSP-AU1 (average of 38.5 kDa) induced NO and cytokine [interleukin (IL)-1α, -1β, -6, -10, tumor necrosis factor (TNF; designated previously as TNF-α), and granulocyte macrophage-colony stimulating factor (GM-CSF)] production by human peripheral blood mononuclear cells (PBMCs) and monocyte/macrophages. CSP-AU1-induced secretion of TNF was prevented by Toll-like receptor 4 (TLR4) antagonist LPS-RS, indicating a role for TLR4 signaling. Treatment with CSP-AU1 also induced phosphorylation of a number of MAPKs in human PBMC and activated AP-1/NF-κB. In vivo treatment of mice with CSP-AU1 and CSP-NU1 resulted in increased serum IL-6, IL-10, TNF, monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein (MIP)-1α/CCL3, and MIP-1β/CCL4. CSP-AU1 treatment of mice with EAE (50 mg/kg, i.p., daily, 13 days) resulted in significantly reduced disease severity in this experimental model of multiple sclerosis. Levels of IL-13, TNF, interferon (IFN)-γ, IL-17, and GM-CSF were also significantly decreased, whereas transforming growth factor (TGF)-β was increased in LN cells from CSP-AU1-treated EAE mice.

CONCLUSIONS

Polysaccharide CSP-AU1 is a potent natural innate immunomodulator with a broad spectrum of agonist activity in vitro and immunosupressive properties after chronic administration in vivo.