Antiinflammatory C-glucosyl chromone from Aloe barbadensis

An insight into the last 5-year patents on Porphyromonas gingivalis and Streptococcus mutans, the pivotal pathogens in the oral cavity

INTRODUCTION

The oral cavity harbors an extensive array of over 700 microorganisms, forming the most complex biome of the entire human body, with bacterial species being the most abundant. Oral diseases, e.g. periodontitis and caries, are strictly associated with bacterial dysbiosis. Porphyromonas gingivalis and Streptococcus mutans stand out among bacteria colonizing the oral cavity.

AREAS COVERED

After a brief overview of the bacterial populations in the oral cavity and their roles in regulating (flora) oral cavity or causing diseases like periodontal and cariogenic pathogens, we focused our attention on P. gingivalis and S. mutans, searching for the last-5-year patents dealing with the proposal of new strategies to fight their infections. Following the PRISMA protocol, we filtered the results and analyzed over 100 applied/granted patents, to provide an in-depth insight into this R&D scenario.

EXPERT OPINION

Several antibacterial proposals have been patented in this period, from both chemical - peptides and small molecules - and biological - probiotics and antibodies - sources, along with natural extracts, polymers, and drug delivery systems. Most of the inventors are from China and Korea and their studies also investigated anti-inflammatory and antioxidant effects, being beneficial to oral health through a prophylactic, protective, or curative effect.

Unveiling the Latest Breakthroughs: A Comprehensive Review of the Therapeutic Activity and Safety Profile of Aloe vera

The use of herbal drugs as alternative and complementary medicine has increased in popularity, raising concerns about their safety profile. Aloe vera, a plant with diverse therapeutic properties, has been extensively used for centuries. This review aims to assess the therapeutic activity and safety profile of Aloe vera. A comprehensive literature search was conducted to gather relevant information from various biomedical databases. The chemical composition, mechanism of action, and therapeutic activities of Aloe vera were analyzed. Aloe vera contains numerous active components such as vitamins, enzymes, minerals, sugars, lignin, saponins, and anthraquinones. Its mechanisms of action involve collagen synthesis, anti-inflammatory effects, immune modulation, laxative properties, and antiviral activity. Aloe vera has demonstrated potential therapeutic benefits in wound healing, diabetes management, liver and kidney protection, and glycemic control. However, it is essential to consider potential side effects, such as skin irritation and allergic reactions. This review provides evidence-based information to improve patient safety and promote informed decisions regarding the use of Aloe vera as a therapeutic agent.

Green Alternatives as Antimicrobial Agents in Mitigating Periodontal Diseases: A Narrative Review

Periodontal diseases and dental caries are the most common infectious oral diseases impacting oral health globally. Oral cavity health is crucial for enhancing life quality since it serves as the entranceway to general health. The oral microbiome and oral infectious diseases are strongly correlated. Gram-negative anaerobic bacteria have been associated with periodontal diseases. Due to the shortcomings of several antimicrobial medications frequently applied in dentistry, the lack of resources in developing countries, the prevalence of oral inflammatory conditions, and the rise in bacterial antibiotic resistance, there is a need for reliable, efficient, and affordable alternative solutions for the prevention and treatment of periodontal diseases. Several accessible chemical agents can alter the oral microbiota, although these substances also have unfavorable symptoms such as vomiting, diarrhea, and tooth discoloration. Natural phytochemicals generated from plants that have historically been used as medicines are categorized as prospective alternatives due to the ongoing quest for substitute products. This review concentrated on phytochemicals or herbal extracts that impact periodontal diseases by decreasing the formation of dental biofilms and plaques, preventing the proliferation of oral pathogens, and inhibiting bacterial adhesion to surfaces. Investigations examining the effectiveness and safety of plant-based medicines have also been presented, including those conducted over the past decade.

Polymeric Membranes of Chitosan/Aloe Vera Gel Fabrication With Enhanced Swelling and Antimicrobial Properties for Biomedical Applications

Since ancient times, medicinal plants have been used as traditional medicine to treat a variety of ailments. Aloe vera (AV) gel's therapeutic potential is one of the most effective approach in the fabrication of functional materials. The current study aimed to prepare the AV and chitosan (CS) membranes using various cross-linkers that were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform-infrared (FT-IR) spectroscopy, thermal gravimetric analysis (TGA), and ultraviolet-visible (UV-Visible) techniques, as well as swelling ratio and antimicrobial studies. SEM analysis revealed that the membrane is porous, with interconnected pores. The inclusion of AV contents in the membrane improved thermal stability and crystallinity. The swelling ratio of the ACPG-3 membrane with a 2:1 CS to AV ratio was 366%. The membranes showed promising antimicrobial activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pasteurella multocida strains. The findings revealed that polymeric CS/AV membranes have effective potential for use in the biomedical field.

Advances in plant-derived C-glycosides: Phytochemistry, bioactivities, and biotechnological production

C-glycosides represent a large group of natural products with a C-C bond between the aglycone and the sugar moiety. They exhibit great structural diversity, wide natural distribution, and significant biological activities. By the end of 2021, at least 754 C-glycosides and their derivatives have been isolated and characterized from plants. Thus far, 66 functional C-glycosyltransferases (CGTs) have been discovered from plants, and provide green and efficient approaches to synthesize C-glycosides. Herein, advances in plant-derived C-glycosides are comprehensively summarized from aspects of structural diversity and identification, bioactivities, and biotechnological production. New strategies to discover novel C-glycosides and CGTs, as well as the applications of biotechnological methods to produce C-glycosides in the future are also discussed.

Cosmeceuticals: A Newly Expanding Industry in South Africa

Africa is counted amongst the cosmetic market contributors; however, South Africa’s remarkable plant diversity is still largely untapped in terms of its potential for medicinal and cosmetic purposes. Thus, we aim to provide a critical assessment of the advancements made in South African cosmeceuticals with emphasis towards online local companies/brands that are manufactured by small, medium and micro enterprises (SMMEs). For the current study, we limited our search of herbal cosmeceutical products to SMMEs with online websites, or products traded in other online cosmetic directories such as ‘Faithful to Nature’ and ‘African Botanicals’ using a simple Google search. We recorded more than 50 South African SMME companies/brands involved in the trade of cosmeceuticals. Skin and hair care were the major product categories widely traded in these online platforms. Furthermore, few patents were recorded from South African researchers and institutions thereof, which is quite alarming considering the extensive research that has been undertaken to study these commercially valuable plants. Based on the increasing number of new products and the wide pool of economically important plants coupled to their associated rich indigenous knowledge systems, the cosmeceutical sector can contribute to the economy, job creation, entrepreneurship skills, socio-economic development and intellectual property generation.

Naturally Occurring Chromone Glycosides: Sources, Bioactivities, and Spectroscopic Features

Chromone glycosides comprise an important group of secondary metabolites. They are widely distributed in plants and, to a lesser extent, in fungi and bacteria. Significant biological activities, including antiviral, anti-inflammatory, antitumor, antimicrobial, etc., have been discovered for chromone glycosides, suggesting their potential as drug leads. This review compiles 192 naturally occurring chromone glycosides along with their sources, classification, biological activities, and spectroscopic features. Detailed biosynthetic pathways and chemotaxonomic studies are also described. Extensive spectroscopic features for this class of compounds have been thoroughly discussed, and detailed 13C-NMR data of compounds 1-192, have been added, except for those that have no reported 13C-NMR data.

Dihydroisocoumarins, Naphthalenes, and Further Polyketides from Aloe vera and A. plicatilis: Isolation, Identification and Their 5-LOX/COX-1 Inhibiting Potency

The present study aims at the isolation and identification of diverse phenolic polyketides from Aloe vera (L.) Burm.f. and Aloe plicatilis (L.) Miller and includes their 5-LOX/COX-1 inhibiting potency. After initial Sephadex-LH20 gel filtration and combined silica gel 60- and RP18-CC, three dihydroisocoumarins (nonaketides), four 5-methyl-8-C-glucosylchromones (heptaketides) from A. vera, and two hexaketide-naphthalenes from A. plicatilis have been isolated by means of HSCCC. The structures of all polyketides were elucidated by ESI-MS and 2D ¹H/¹³C-NMR (HMQC, HMBC) techniques. The analytical/preparative separation of 3R-feralolide, 3′-O-β-d-glucopyranosyl- and the new 6-O-β-d-glucopyranosyl-3R-feralolide into their respective positional isomers are described here for the first time, including the assignment of the 3R-configuration in all feralolides by comparative CD spectroscopy. The chromones 7-O-methyl-aloesin and 7-O-methyl-aloeresin A were isolated for the first time from A. vera, together with the previously described aloesin (syn. aloeresin B) and aloeresin D. Furthermore, the new 5,6,7,8-tetrahydro-1-O-β-d-glucopyranosyl- 3,6R-dihydroxy-8R-methylnaphtalene was isolated from A. plicatilis, together with the known plicataloside. Subsequently, biological-pharmacological screening was performed to identify Aloe polyketides with anti-inflammatory potential in vitro. In addition to the above constituents, the anthranoids (octaketides) aloe emodin, aloin, 6′-(E)-p-coumaroyl-aloin A and B, and 6′-(E)-p-coumaroyl-7-hydroxy-8-O-methyl-aloin A and B were tested. In the COX-1 examination, only feralolide (10 µM) inhibited the formation of MDA by 24%, whereas the other polyketides did not display any inhibition at all. In the 5-LOX-test, all aloin-type anthranoids (10 µM) inhibited the formation of LTB₄ by about 25–41%. Aloesin also displayed 10% inhibition at 10 µM in this in vitro setup, while the other chromones and naphthalenes did not display any activity. The present study, therefore, demonstrates the importance of low molecular phenolic polyketides for the known overall anti-inflammatory activity of Aloe vera preparations.

Aloe djiboutiensis: Antioxidant Activity, Molecular Networking-Based Approach and In Vivo Toxicity of This Endemic Species in Djibouti

For the first time, the study of the antioxidant activity, the characterization of the phytoconstituants, and the evaluation of in vitro and in vivo toxicity of A. djiboutiensis leave and latex are performed. The antioxidant activity of both latex (ADL) and the methanolic extract of leaves (ADM) is determined using 1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) scavenging radical methods and ferric reducing/antioxidant power (FRAP) assay. The phytochemical study of latex is done using Liquid Chromatography-Mass Spectrometry (LC-MS/MS) and a molecular networking-based approach. The evaluation of in vivo toxicity is performed on mice by oral gavage with a suspension of ADL. Our results show that weak antioxidant activity of ADL and ADM in opposition to their high polyphenol, 83.01 mg and 46.4 mg expressed in gallic acid equivalent (GAE)/g of dry weight (DW), respectively, and flavonoid contents 13.12 mg and 4.25 mg expressed in quercetin equivalent (QE)/g dry weight (DW), respectively. Using the Global Natural Products Social Molecular Networking (GNPS) website, nine (9) anthraquinones derivatives, ten (10) chromones derivatives, two (2) flavonols/ chromones isomers are annotated in the molecular network. The treated mice do not display abnormalities in their general physical appearance and biochemistry parameters, compared to the controls. Only glucose and calcium levels are slightly higher in male treated mice compared to the vehicles.

Aloe Vera; A new treatment for atrophic vaginitis, A randomized double-blinded controlled trial

AIM OF THE STUDY

Vaginal atrophy is of the most common problems during menopause with significant psychosocial and medical consequences. Estrogen as an approved therapy for vaginal atrophy can be associated with adverse effects and several contraindications in menopause patients. The aim is to compare the effect of Aloe Vera vaginal cream with commercially available estrogen vaginal cream for management of vaginal atrophy in menopause females.

MATERIALS AND METHODS

This is a double-blinded randomized controlled trial on 60menopause female with complaints of vaginal atrophy symptoms. Subjects were randomly allocated in two groups of 30 patients, named as estrogen and Aloe Vera groups. Vaginal health index (VHI), maturity value (MV), vaginal cytologic smear, transvaginal sonography (TVS) and severity of symptoms related to vaginal atrophy were assessed before and after 6-weeks of vaginal cream administration.

RESULTS

Comparison of MV before and after treatment revealed that superficial cells were significantly increased after administration of both vaginal cream (6.67 VS 54.33 in Aloe Vera group; 4.33 VS 59.67 in estrogen group). In addition, VHI (13.83 vs 20.13 in Aloe Vera group; 13.97 vs 19.93 in estrogen group) and symptoms of vaginal atrophy (3.63 vs 1.10 in Aloe Vera group; 3.90 vs 0.66 in estrogen groups) were also significantly improved after treatment in both groups. There was no significant difference between groups after treatment except for fluid volume with a superiority in Aloe Vera group (P-value = 0.004) CONCLUSION: Aloe Vera vaginal cream can be as effective as estrogen vaginal cream in the management of vaginal atrophy in menopause females.

Identification of Potential SARS-CoV-2 Main Protease and Spike Protein Inhibitors from the Genus Aloe: An In Silico Study for Drug Development

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) disease is a global rapidly spreading virus showing very high rates of complications and mortality. Till now, there is no effective specific treatment for the disease. Aloe is a rich source of isolated phytoconstituents that have an enormous range of biological activities. Since there are no available experimental techniques to examine these compounds for antiviral activity against SARS-CoV-2, we employed an in silico approach involving molecular docking, dynamics simulation, and binding free energy calculation using SARS-CoV-2 essential proteins as main protease and spike protein to identify lead compounds from Aloe that may help in novel drug discovery. Results retrieved from docking and molecular dynamics simulation suggested a number of promising inhibitors from Aloe. Root mean square deviation (RMSD) and root mean square fluctuation (RMSF) calculations indicated that compounds 132, 134, and 159 were the best scoring compounds against main protease, while compounds 115, 120, and 131 were the best scoring ones against spike glycoprotein. Compounds 120 and 131 were able to achieve significant stability and binding free energies during molecular dynamics simulation. In addition, the highest scoring compounds were investigated for their pharmacokinetic properties and drug-likeness. The Aloe compounds are promising active phytoconstituents for drug development for SARS-CoV-2.

Aloe vera gel homogenate shows anti-inflammatory activity through lysosomal membrane stabilization and downregulation of TNF-α and Cox-2 gene expressions in inflammatory arthritic animals

Background

Aloe vera leaf gel has proven efficacious roles in the amelioration of several human diseases and illness-conditions. Specific purified gel-derived bio-constituents as well as the naturally harvested unprocessed A. vera gel have shown promise in modifying systemic inflammation. However, the synergistic role of natural herbal remedies, a mainstay of traditional Indian Ayurveda, has not been evaluated rigorously in this plant. In this study, the prevention of membrane lysis and protein denaturation in the presence of A. vera gel homogenate up to the concentration of 1000 μg/ml of gel has been assessed in vitro. Also, regulation of expression of inflammation-mediator genes (TNF-α and Cox-2) has been investigated in vivo in Freund’s complete adjuvant (FCA)-induced inflammatory arthritic Wistar albino rats in a 28-day long study following the daily oral supplementation of Aloe vera gel homogenate doses up to 0.40 and 0.80 g/kg body weight (low-dose and high-dose groups respectively).

Results

Our results indicated that A. vera gel homogenate inhibits hypotonicity-induced (74.89 ± 1.26%) and heat-induced (20.86 ± 0.77%) RBC membrane lyses respectively at a concentration of 1000 μg/ml, compared to indomethacin standard (80.52 ± 0.65% and 43.98 ± 1.52% respectively at 200 μg/ml concentration). The similar concentration of gel also showed 39.35 ± 4.25% inhibition of protein denaturation compared to standard diclofenac sodium (46.74 ± 1.84% at 100 μg/ml concentration) in vitro. When assessed in vivo, TNF-α expression was found to be decreased by 35.88% and 38.52%, and Cox-2 expression was found to be decreased by 31.65% and 34.96%, in low-dose and high-dose groups respectively, when compared to the arthritic controls.

Conclusions

Our findings justify the role of unprocessed A. vera gel homogenate in preventing tissue damage and in the downregulation of TNF-α and Cox-2 gene expressions for the immune-modulation of inflammatory arthritis condition.

Palladium-mediated C–O bond activation of benzopyrone in 4-oxo-4H-chromone-3-carbaldehyde-4(N)-substituted thiosemicarbazone: synthesis, structure, nucleic acid/albumin interaction, DNA cleavage, antioxidant and cytotoxic studies

Palladium ion-mediated C–O activation at the C2 carbon of the benzopyrone moiety of 3-formylchromone-4(N)-substituted thiosemicarbazone (HL1–4) has been observed in square-planar palladium(ii) complexes.

Exploring and applying the substrate promiscuity of a C-glycosyltransferase in the chemo-enzymatic synthesis of bioactive C-glycosides

Bioactive natural C-glycosides are rare and chemical C-glycosylation faces challenges while enzymatic C-glycosylation catalyzed by C-glycosyltransferases provides an alternative way. However, only a small number of C-glycosyltransferases have been found, and most of the discovered C-glycosyltransferases prefer to glycosylate phenols with an acyl side chain. Here, a promiscuous C-glycosyltransferase, AbCGT, which is capable of C-glycosylating scaffolds lacking acyl groups, is identified from Aloe barbadensis. Based on the substrate promiscuity of AbCGT, 16 C-glycosides with inhibitory activity against sodium-dependent glucose transporters 2 are chemo-enzymatically synthesized. The C-glycoside 46a shows hypoglycemic activity in diabetic mice and is biosynthesized with a cumulative yield on the 3.95 g L^‒1 scale. In addition, the key residues involved in the catalytic selectivity of AbCGT are explored. These findings suggest that AbCGT is a powerful tool in the synthesis of lead compounds for drug discovery and an example for engineering the catalytic selectivity of C-glycosyltransferases.

C-glycosides are of pharmaceutical interest due to their stability against in vivo hydrolysis, however their enzymatic synthesis faces challenges. Here, the authors report a C-glycosyltransferase from Aloe barbadensis catalysing the C-glycosylation of drug-like acceptors to generate bioactive C-glycosides.

Effects of Skin Lightening Cream Agents - Hydroquinone and Kojic Acid, on the Skin of Adult Female Experimental Rats

Introduction

Skin bleaching is the act of using steroid- and chemical-containing products to lighten the skin. Hydroquinone and kojic acid are often used in skin bleaching creams. Hydroquinone was suspected to be harmful. This study investigated the effects of kojic acid and hydroquinone on the skin of adult female Wistar rats and the potential use of aloe vera for amelioration.

Materials and Methods

Eighty [n=80] adult female Wistar rats with an average weight of 120 g were randomly divided into eight groups, marked A, B, C, D, E, F, G, and H. Group A animals served as the control group; group B was treated with 2% hydroquinone, group C was treated with 2% kojic acid, group D was treated with 4% hydroquinone, group E was treated with 4% kojic acid, group F was treated with 2% hydroquinone and 2% kojic acid, group G was treated with 4% hydroquinone and 4% kojic acid, and group H was treated with 4% hydroquinone, 4% kojic acid, and aloe vera. The preparations were applied to the tail skin and treatment lasted 28 days. Skin samples were excised and processed using H&E, Masson’s trichrome, and p65 immunohistochemical assays on tissue sections.

Results

Hydroquinone caused structural disruptions of the stratum corneum of the epidermis and the overlying keratin. p65 was also prominently expressed in the treated groups. Hydroquinone reduced skin thickness and caused epidermis disruption.

Discussion

The prominent expression of p65 in the sections indicated deleterious effects of hydroquinone. Kojic acid was not found to have deleterious effects. Aloe vera prevented extensive disruption of stratum corneum by hydroquinone. The use of hydroquinone in skin lightening creams might raise health concerns. Aloe vera could be protective against hydroquinone.

Chemical Constituents, Antimicrobial Activity, and Food Preservative Characteristics of Aloe vera Gel

Edible coating gels developed from the Aloe vera plant have been used as a traditional medicine for about 3000 years. Aloe vera contains approximately 110 potentially active constituents from six different classes: chromone and its glycoside derivatives; anthraquinone and its glycoside derivatives; flavonoids; phenylpropanoids and coumarins; phenylpyrone and phenol derivatives; and phytosterols and others. Apart from medicinal uses, Aloe gels have an important role in food preservation as edible coatings. They provide an edible barrier for atmospheric gases and moisture and help to reduce the respiration and transpiration of fresh produce, which helps to preserve its postharvest quality. To date, numerous studies have been conducted on the postharvest use of Aloe vera gel. The present review article summarizes and discusses existing available information about the chemical constituents, antimicrobial activity, and food preservative characteristics of Aloe vera.

Anti-inflammatory effects of aloe vera on soy meal-induced intestinal inflammation in zebrafish

Soybean meal is one of the most promising alternatives to replace fishmeal in the aquaculture industry. However, its ingestion triggers an intestinal inflammatory process that compromises fish health and nutrition. Therefore, finding strategies that reduce the deleterious effects of a soy protein-based diet are relevant. In this work we analyzed the effects of an aloe vera (Aloe barbadensis miller, AV) extract on intestinal inflammation and innate immunity of zebrafish by adding it to the water and by supplementing it in a soybean meal-based diet. To search for potential immunomodulatory effects of AV, we tested its effectiveness in two inflammation assays and compared fish fed with either fishmeal or soybean meal-based feed supplemented with AV. Our results show a strong anti-inflammatory effect of AV. Furthermore, while soy-based meal strongly induces the expression of inflammation markers, supplementation with AV reverted this effect. Finally, we show that fish fed with a soy meal diet are highly susceptible to bacterial infection, but that this condition is significantly reduced when the soy meal is supplemented with AV. Our results suggest that AV is a good candidate to be incorporated as an additive in farmed fish diets to facilitate the replacement of fishmeal by soybean meal, maintaining intestinal health.

Molecular Design, Synthesis, and Biological Evaluation of 2-Hydroxy-3-Chrysino Dithiocarbamate Derivatives

A series of 2-hydroxy-3-chrysino dithiocarbamate derivatives (3a–k) were designed, synthesized, and characterized for their structure determination by ¹H NMR, ¹³C NMR, and HRMS (ESI) spectral data. They were screened for their in vitro biological activities against a panel of selected bacterial and fungal strains. These antimicrobial studies indicate that some of the analogues manifested significant activity compared to standard drugs. Among the synthetic analogues (3a–k), compounds 3d, 3f, and 3j exhibited very good antibacterial activity and compounds 3d, 3f, and 3h showed very good antifungal activity compared to the standard drugs penicillin and itrazole, respectively. The compounds 3e, 3g, and 3h showed moderate antibacterial activity and the compounds 3j and 3k showed moderate antifungal activity. Molecular docking studies were performed and the experimental antimicrobial screening results were also correlated with the binding energy values obtained by molecular docking. The synthesized chrysin analogues (3a–k) have obeyed Lipinski’s “rule of five” and have drug-likeness.

Design, synthesis and biological evaluation of novel neuchromenin analogues as potential antifungal agents

In continuation of our program to discover new potential antifungal agents, thirty-two neuchromenin analogues were synthesized and characterized by the spectroscopic analysis. By using the mycelium growth rate method, the target compounds were evaluated systematically for antifungal activities in vitro against six plant pathogenic fungi, and structure-activity relationships (SAR) were derived. Compounds 6b-c, and 6l showed obvious inhibition activity on each of the fungi at 50 μg/mL. For the corresponding fungi, 7 of the compounds showed average inhibition rates of >80% at 50 μg/mL; especially, compounds 6b, 6d-e, and 6i-l displayed more potent antifungal activity against A. solani than that of thiabendazole (a positive control). Moreover, compound 6c also exhibited good activity against C. lunata with EC₅₀ values of 12.7 μg/mL, and the value was much superior to that of thiabendazole (EC₅₀ = 59.7 μg/mL). SAR analysis showed that the presence of conjugated structure, bearing a C=C bond conjugated to the C=O group, obviously decreased the activity; the type and position of the substituted R₅ significantly influenced the activity. Furthermore, the significantly bioactive compounds 6b-e, 6g, 6i and 6l showed very low toxicities against HL-7702, BEL-7402 and HCT-8 cells. Resistance development assay indicated that compounds 6b-e and 6l failed to induce the two tested strains of fungi to develop resistance. SEM analysis initially revealed that compound 6d may exert its antifungal effect by damaging fungal cell wall.

Visnagin and benzofuran scaffold-based molecules as selective cyclooxygenase-2 inhibitors with anti-inflammatory and analgesic properties: design, synthesis and molecular docking

A series of new visnagin and benzofuran scaffold-based molecules was designed and synthesized as anti-inflammatory and analgesic agents. Biological screening of these compounds showed that they exhibit potent anti-inflammatory/analgesic activity with a safer side effect profile in in vivo mouse models. In vitro cyclooxygenase (COX) inhibition assay showed that the compounds elicit their function through selective COX-2 inhibition. Molecular docking study also revealed the ability of the compounds to correctly recognize the active site and achieve noncovalent binding interactions with key residues therein. The best combined profile of anti-inflammatory, analgesic and COX-2 selective inhibition properties in association with low gastrotoxicity was displayed by the analogs 8, 11b and 19d, which can be considered as promising leads for further future optimization.

Natural chromones as potential anti-inflammatory agents: Pharmacological properties and related mechanisms

Chromones are a group of natural substances with a diversity of biological activities. Herein we assessed the pharmacological potential of three chromones (1, 2 and 3) isolated from Dictyoloma vandellianum as anti-inflammatory agents using in vitro and in vivo approaches. During in vitro screening, the production of NO and cytokines by macrophages stimulated with LPS and IFN-γ was inhibited by all chromones at concentrations (5-20 μM) that did not induce cytotoxicity. Analysis of pharmacokinetic parameters (in vitro half-life and intrinsic clearance) using human liver microsomes revealed that 3 has a superior pharmacokinetic profile, compared to 1 and 2. Treatment with 3 (100 mg/kg, ip) did not affect the mice motor performance, while 1 and 2 induced motor deficit. Taking into account the pharmacokinetic profile and absence of motor impairment, 3 was selected for further pharmacological characterization. Corroborating the data from in vitro screening, treatment of cell cultures with 3 (5-20 μM) reduced TNF-α, IL-6 and IL-1β production by stimulated macrophages. In the complete Freund's adjuvant-induced paw inflammation model in mice, 3 (25 and 50 mg/kg, ip) inhibited mechanical hyperalgesia, edema and cytokine production/release (IL-1β, IL-6 and TNF-α). 3 (5-20 μM) also reduced the transcriptional activity of NF-κB in stimulated macrophages. Furthermore, treatment with RU486, a glucocorticoid receptor (GR) antagonist, partially prevented the inhibitory effect of 3 on macrophages, indicating that this chromone exerts its anti-inflammatory effects in part through the activation of GR. The results presented herein demonstrate the pharmacological potential of natural chromones, highlighting 3 as a possible candidate for the drug discovery process targeting new anti-inflammatory drugs.

Prevalence and current therapy in chronic liver disorders

BACKGROUND

Herbal medicine plays an important role in health, particularly in remote parts of developing areas with few health facilities. According to WHO estimates, about three-quarters of the world's population currently use herbs or traditional medicines to treat various ailments, including liver diseases. Several studies have found that the use of medicinal plants was effective in the treatment of infectious and non-infectious diseases. Hepatitis and liver cirrhosis associated with many clinical manifestations can be treated with allopathic medicines, but reports of a number of side effects including immunosuppression, bone marrow suppression, and renal complications have motivated researchers to explore more natural herbal medicines with low or no side effects and with high efficacy in treating hepatic diseases.

METHODS

Databases including PubMed, Medline, and Google Scholar were searched for findings on the hepatoprotective effects of plants.

RESULTS

Various medicinal plants are used for the treatment of liver disorders. The range of alternative therapies is huge, and they are used worldwide, either as part of primary health care or in combination with conventional medicine. Hepatoprotective plants contain a variety of chemical constituents including flavonoids, alkaloids, glycosides, carotenoids, coumarins, phenols, essential oil, organic acids, monoterpenes, xanthenes, lignans, and lipids.

CONCLUSION

This review shows that numerous plants are found to contain hepatoprotective compounds. However, further studies are needed to determine their association with existing regimes of antiviral medicines and to develop evidence-based alternative medicine to cure different kinds of liver disease in humans.

Rh(iii)-Catalyzed C–H activation/annulation of salicylaldehydes with sulfoxonium ylides for the synthesis of chromones

A rhodium(iii)-catalyzed C–H activation/annulation of salicylaldehydes with sulfoxonium ylides has been developed for the formation of structurally diverse 2-substituted chromones.

X-ray crystallographic and validated HPTLC analysis of the biomarker chromone glucoside (schumanniofioside A) isolated from Acalypha fruticosa growing in Saudi Arabia

A chromone glucoside 2-methyl-5,7-dihydroxychromone 5-O-β-D-glucopyranoside (schumanniofioside A, compound 1) was isolated from the methanol extract of Acalypha fruticosa. The structure of compound 1 was fully assigned based on nuclear magnetic resonance (NMR) (¹H, ¹³C and 2D) spectra and electrospray ionization mass spectrum (ESI-MS) in addition to X-ray Crystallography. The molecules were packed in the crystal structure by eight intermolecular O—H⋯O and C—H⋯O interactions. The structure of compound 1 belongs to monoclinic, P2₁, a = 9.1989 (4) Å, b = 4.6651 (2) Å, c = 20.4042 (7) Å, β = 97.862 (3)°, V = 867.31 (6) ų, Z = 2, wR_ref(F²) = 0.101, T = 100 K. Thus, the bond angles, bond lengths and absolute structure of compound 1 were confirmed by its X-ray structure. A validated HPTLC method was developed for the quantitative analysis of compound 1 in chloroform and methanol extracts of A. fruticosa. It was found to furnish a compact and sharp band of compound 1 at R_f = 0.13 ± 0.005 using chloroform, methanol and glacial acetic acid [17:3:0.5 (v/v/v)] as mobile phase. The LOD and LOQ for compound 1 were found to be 17.86 and 54.13 ng/band, respectively. Compound 1 was found in both chloroform and methanol extracts of the plant (0.03% w/w and 0.31% w/w, respectively). The proposed HPTLC method can be used for the further analysis of schumanniofioside A in different plant extracts, herbal formulations and biological samples as well as in process quality control.

Electrospun Polycaprolactone/Aloe Vera_Chitosan Nanofibrous Asymmetric Membranes Aimed for Wound Healing Applications

Today, none of the wound dressings available on the market is fully capable of reproducing all the features of native skin. Herein, an asymmetric electrospun membrane was produced to mimic both layers of skin. It comprises a top dense layer (manufactured with polycaprolactone) that was designed to provide mechanical support to the wound and a bottom porous layer (composed of chitosan and Aloe Vera) aimed to improve the bactericidal activity of the membrane and ultimately the healing process. The results obtained revealed that the produced asymmetric membranes displayed a porosity, wettability, as well as mechanical properties similar to those presented by the native skin. Fibroblast cells were able to adhere, spread, and proliferate on the surface of the membranes and the intrinsic structure of the two layers of the membrane is capable of avoiding the invasion of microorganisms while conferring bioactive properties. Such data reveals the potential of these asymmetric membranes, in the near future, to be applied as wound dressings.

Synthesis of new chromeno-carbamodithioate derivatives and preliminary evaluation of their antioxidant activity and molecular docking studies

New chromeno carbamodithioates (7a-i), have been synthesized from 2, 3-dimethyl-7-(oxiran-2-ylmethoxy)-4H-chromen-4-one (5), carbondisulphide and commercially available acyclic and cyclic secondary amines in acetonitrile with good to excellent yields. The free radical scavenging activity of novel chromone-carbamodithioate analogues was quantitatively estimated by spectrophotometric method. Whereas, molecular docking studies were performed with the active site of cyclooxygenase-2 to identify hydrogen bonding, hydrophobic and ionic interactions between protein and ligands. The compounds 7g and 7h demonstrated potent antioxidant activity with IC₅₀ of 1.405±0.019mM and 1.382±0.35mM respectively compared to Ascorbic acid.

Phomopsichin A-D; Four New Chromone Derivatives from Mangrove Endophytic Fungus Phomopsis sp. 33

Four new chromone derivatives, phomopsichins A-D (1-4), along with a known compound, phomoxanthone A (5), were isolated from the fermentation products of mangrove endophytic fungus Phomopsis sp. 33#. Their structures were elucidated based on comprehensive spectroscopic analysis coupled with single-crystal X-ray diffraction or theoretical calculations of electronic circular dichroism (ECD). They feature a tricyclic framework, in which a dihydropyran ring is fused with the chromone ring. Compounds 1-5 showed weak inhibitory activities on acetylcholinesterase as well as α-glucosidase, weak radical scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH) as well as OH, and weak antimicrobial activities. Compounds 1-4 showed no cytotoxic activity against MDA-MB-435 breast cancer cells. Their other bioactivities are worthy of further study, considering their unique molecular structures.

Natural Therapeutic Options in Endodontics - A Review

Complete eradication of microbial biofilms and elimination of the smear layer are the key factors during endodontic treatment. Various chemical irrigants have been proposed in the literature for the same. The major setback with these chemical irrigants is that they are not bio-friendly to the dental and peri-radicular tissues. In the recent years, research to use natural products for root canal disinfection has gained importance. The aim of this article is to compile various herbal products that have been used as an irrigants and intracanal medicaments in the field of Endodontics to eradicate the biofilm and remove smear layer.

Hepatoprotective Activity of Herbal Composition SAL, a Standardize Blend Comprised of Schisandra chinensis, Artemisia capillaris, and Aloe barbadensis

Some botanicals have been reported to possess antioxidative activities acting as scavengers of free radicals rendering their usage in herbal medicine. Here we describe the potential use of “SAL,” a standardized blend comprised of three extracts from Schisandra chinensis, Artemisia capillaris, and Aloe barbadensis, in mitigating chemically induced acute liver toxicities. Acetaminophen and carbon tetrachloride induced acute liver toxicity models in mice were utilized. Hepatic functional tests from serum collected at T24 and hepatic glutathione and superoxide dismutases from liver homogenates were evaluated. Histopathology analysis and merit of blending 3 standardized extracts were also confirmed. Statistically significant and dose-correlated inhibitions in serum ALT ranging from 52.5% (p = 0.004) to 34.6% (p = 0.05) in the APAP and 46.3% (p < 0.001) to 29.9% (p = 0.02) in the CCl₄ models were observed for SAL administered at doses of 400–250 mg/kg. Moreover, SAL resulted in up to 60.6% and 80.2% reductions in serums AST and bile acid, respectively. The composition replenished depleted hepatic glutathione in association with an increase of hepatic superoxide dismutase. Unexpected synergistic protection from liver damage was also observed. Therefore, the composition SAL could be potentially utilized as an effective hepatic-detoxification agent for the protection from liver damage.

Soluble epoxide hydrolase inhibitory activity of anthraquinone components from Aloe

Aloe is a short-stemmed succulent herb widely used in traditional medicine to treat various diseases and as raw material in cosmetics and heath foods. In this study, we isolated and identified two new anthraquinone derivatives, aloinoside C (6) and aloinoside D (7), together with six known compounds from an aqueous dissolved Aloe exudate. Their structures were identified by spectroscopic analysis. The inhibitory effects of the isolated compounds on soluble epoxide hydrolase (sEH) were evaluated. Compounds 1-8 inhibited sEH activity potently, with IC50 values ranging from 4.1±0.6 to 41.1±4.2 μM. A kinetic analysis of compounds 1-8 revealed that the inhibitory actions of compounds 1, 6 and 8 were non-competitive, whereas those of compounds 2-5 and 7 were the mixed-type. Molecular docking increases our understanding of receptor-ligand binding of all compounds. These results demonstrate that compounds 1-8 from Aloe are potential sEH inhibitors.

Spectroscopic (FT-IR and FT-Raman) investigation, first order hyperpolarizability, NBO, HOMO-LUMO and MEP analysis of 6-nitrochromone by ab initio and density functional theory calculations

The vibrational spectral analysis is carried out using FT-Raman and FT-IR spectroscopy in the range 3500-50 cm(-1) and 4000-400 cm(-1), respectively, for 6-nitrochromone (6NC). The molecular structure, fundamental vibrational frequencies and intensity of the vibrational bands are interpreted with the aid of structure optimization and normal coordinates force field calculation based on ab initio HF and DFT gradient calculations employing the HF/6-311++G(d,p) and B3LYP/6-311++G(d,p) basis set. Stability of the molecule has been analyzed using NBO analysis. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. Thermodynamic properties like entropy, heat capacity, zero-point energy and Mulliken's charge analysis have been calculated for the 6NC. The complete assignments were performed on the basis of total energy distribution (TED) of the vibrational modes with scaled quantum mechanical (SQM) method. The MEP map shows the negative potential sites are on oxygen atoms as well as the positive potential sites are around the hydrogen atoms.

Evaluation of biological properties and clinical effectiveness of Aloe vera: A systematic review

Aloe vera (蘆薈 lú huì) is well known for its considerable medicinal properties. This plant is one of the richest natural sources of health for human beings coming. The chemistry of the plant has revealed the presence of more than 200 different biologically active substances. Many biological properties associated with Aloe species are contributed by inner gel of the leaves. Most research has been centralized on the biological activities of the various species of Aloe, which include antibacterial and antimicrobial activities of the nonvolatile constituents of the leaf gel. Aloe species are widely distributed in the African and the eastern European continents, and are spread almost throughout the world. The genus Aloe has more than 400 species but few, such as A. vera, Aloe ferox, and Aloe arborescens, are globally used for trade. A. vera has various medicinal properties such as antitumor, antiarthritic, antirheumatoid, anticancer, and antidiabetic properties. In addition, A. vera has also been promoted for constipation, gastrointestinal disorders, and for immune system deficiencies. However, not much convincing information is available on properties of the gel. The present review focuses on the detailed composition of Aloe gel, its various phytocomponents having various biological properties that help to improve health and prevent disease conditions.

Aloe vera Aqueous Extract Effect on Morphine Withdrawal Syndrome in Morphine-Dependent Female Rats

BACKGROUND

Aloe vera is a medicinal herb used as an anti-inflammatory and sedative agent.

OBJECTIVES

The current study aimed to evaluate the effect of Aloe vera aqueous extract on morphine withdrawal symptoms in morphine-dependent female rats.

PATIENTS AND METHODS

The current research was performed on 40 female Wista-Albino rats which were made dependent on morphine using Houshyar protocol and were randomly divided into five groups (A, B, C, D, and E). Group A did not receive any agent in the period of handling but other groups (B, C, D and E) received 5, 10, 20 and 40 mg/kg of Aloe vera aqueous extract by gavage, three times daily for a week, respectively. Withdrawal symptoms, stool form, agitation, disparity, floppy eyelids, and body mass variations were checked for 10 days. The obtained data were analyzed using SPSS v.11 software, and Friedman, Kruskal-Wallis, and Mann-Whitney statistical tests. Statistical difference was considered significant (P < 0.05).

RESULTS

The results of the present study showed that agitation, disparity, and floppy eyelids in group E were significantly higher than those of others groups; however, these symptoms in group C were significantly lower than those of the other groups.

CONCLUSIONS

The results of the present study revealed that the Aloe vera aqueous extract had various effects on morphine withdrawal syndrome in morphine-dependent female rats .

A comparative study of antiplaque and antigingivitis effects of herbal mouthrinse containing tea tree oil, clove, and basil with commercially available essential oil mouthrinse

Background:

The relatively safe nature and cost-effectiveness of herbal extracts have led to a resurgent interest in their utility as therapeutic agents. Therefore, this prospective, double-blind, randomly controlled clinical trial was designed to compare the antiplaque and antigingivitis effects of newly formulated mouthrinse containing tea tree oil (TTO), clove, and basil with those of commercially available essential oil (EO) mouthrinse.

Materials and Methods:

Forty patients were selected for a 21-day study period and randomly divided into two groups. The test group patients were given newly formulated herbal mouthrinse and the control group patients were given commercially available EO mouthrinse. The Plaque Index (PI), Gingival Index (GI), and Papillary Marginal Attachment (PMA) Index were recorded at baseline, 14 days, and 21 days. The microbial colony forming units (CFU) were assessed at baseline and 21 days.

Results:

Test group patients using herbal mouthrinse showed significant improvement in GI (0.16), PI (0.57), and PMA (0.02) scores. These improvements were comparable to those achieved with commercially available EO mouthrinse. However, the aerobic and anaerobic CFU of microbiota were reduced with the herbal mouthrinse (P = 0.0000).

Conclusion:

The newly formulated herbal mouthrinse and commercially available mouthrinse were beneficial clinically as antiplaque and antigingivitis agents. Newly formulated mouthrinses showed significant reduction in microbial CFU at 21 days. So, our findings support the regular use of herbal mouthrinse as an antiplaque, antigingivitis, and antimicrobial rinse for better efficacy.

Aloe vera for prevention and treatment of infusion phlebitis

BACKGROUND

Up to 80% of hospitalised patients receive intravenous therapy at some point during their admission. About 20% to 70% of patients receiving intravenous therapy develop phlebitis. Infusion phlebitis has become one of the most common complications in patients with intravenous therapy. However, the effects of routine treatments such as external application of 75% alcohol or 50% to 75% magnesium sulphate (MgSO4) are unsatisfactory. Therefore, there is an urgent need to develop new methods to prevent and alleviate infusion phlebitis.

OBJECTIVES

To systematically assess the effects of external application of Aloe vera for the prevention and treatment of infusion phlebitis associated with the presence of an intravenous access device.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched February 2014) and CENTRAL (2014, Issue 1). In addition the TSC searched MEDLINE to week 5 January 2014, EMBASE to Week 6 2014 and AMED to February 2014. The authors searched the following Chinese databases until 28 February 2014: Chinese BioMedical Database; Traditional Chinese Medical Database System; China National Knowledge Infrastructure; Chinese VIP information; Chinese Medical Current Contents; Chinese Academic Conference Papers Database and Chinese Dissertation Database; and China Medical Academic Conference. Bibliographies of retrieved and relevant publications were searched. There were no restrictions on the basis of date or language of publication.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-randomised controlled trials (qRCTs) were included if they involved participants receiving topical Aloe vera or Aloe vera-derived products at the site of punctured skin, with or without routine treatment at the same site.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data on the study characteristics, description of methodology and outcomes of the eligible trials, and assessed study quality. Data were analysed using RevMan 5.1. For dichotomous outcomes, the effects were estimated by using risk ratio (RR) with its 95% confidence interval (CI). For continuous outcomes, mean differences (MD) with 95% CIs were used to estimate their effects.

MAIN RESULTS

A total of 43 trials (35 RCTs and eight qRCTs) with 7465 participants were identified. Twenty-two trials with 5546 participants were involved in prevention of Aloe vera for phlebitis, and a further 21 trials with 1919 participants were involved in the treatment of phlebitis. The included studies compared external application of Aloe vera alone or plus non-Aloe vera interventions with no treatment or the same non-Aloe vera interventions. The duration of the intervention lasted from one day to 15 days. Most of the included studies were of low methodological quality with concerns for selection bias, attrition bias, reporting bias and publication bias.The effects of external application of fresh Aloe vera on preventing total incidence of phlebitis varied across the studies and we did not combine the data. Aloe vera reduced the occurrence of third degree phlebitis (RR 0.06, 95% CI 0.03 to 0.11, P < 0.00001) and second degree phlebitis (RR 0.18, 95% CI 0.10 to 0.31, P < 0.00001) compared with no treatment. Compared with external application of 75% alcohol, or 33% MgSO4 alone, Aloe vera reduced the total incidence of phlebitis (RR 0.02, 95% CI 0.00 to 0.28, P = 0.004 and RR 0.43, 95% CI 0.24 to 0.78, P = 0.005 respectively) but there was no clear evidence of an effect when compared with 50% or 75% MgSO4 (total incidence of phlebitis RR 0.41, 95% CI 0.16 to 1.07, P = 0.07 and RR 1.10 95% CI 0.54 to 2.25, P = 0.79 respectively; third degree phlebitis (RR 0.28, 95% CI 0.07 to 1.02, P = 0.051 and RR 1.19, 95% CI 0.08 to 18.73, P = 0.9 respectively; second degree phlebitis RR 0.68, 95% CI 0.21 to 2.23, P = 0.53 compared to 75% MgSO4) except for a reduction in second degree phlebitis when Aloe vera was compared with 50% MgSO4 (RR 0.26, 95% CI 0.14 to 0.50, P < 0.0001).For the treatment of phlebitis, Aloe vera was more effective than 33% or 50% MgSO4 in terms of both any improvement (RR 1.16, 95% CI 1.09 to 1.24, P < 0.0001 and RR 1.22, 95% CI 1.16 to 1.28, P < 0.0001 respectively) and marked improvement of phlebitis (RR 1.97, 95% CI 1.44 to 2.70, P < 0.001 and RR 1.56, 95% CI 1.29 to 1.87, P = 0.0002 respectively). Compared with 50% MgSO4, Aloe vera also improved recovery rates from phlebitis (RR 1.42, 95% CI 1.24 to 1.61, P < 0.0001). Compared with routine treatments such as external application of hirudoid, sulphonic acid mucopolysaccharide and dexamethasone used alone, addition of Aloe vera improved recovery from phlebitis (RR 1.75, 95% CI 1.24 to 2.46, P = 0.001) and had a positive effect on overall improvement (marked improvement RR 1.26, 95% CI 1.09 to 1.47, P = 0.0003; any improvement RR 1.23, 95% CI 1.13 to 1.35, P < 0.0001). Aloe vera, either alone or in combination with routine treatment, was more effective than routine treatment alone for improving the symptoms of phlebitis including shortening the time of elimination of red swelling symptoms, time of pain relief at the location of the infusion vein and time of resolution of phlebitis. Other secondary outcomes including health-related quality of life and adverse effects were not reported in the included studies.

AUTHORS' CONCLUSIONS

There is no strong evidence for preventing or treating infusion phlebitis with external application of Aloe vera. The current available evidence is limited by the poor methodological quality and risk of selective outcome reporting of the included studies, and by variation in the size of effect across the studies. The positive effects observed with external application of Aloe vera in preventing or treating infusion phlebitis compared with no intervention or external application of 33% or 50% MgSO4 should therefore be viewed with caution.