Enzymatic, antimicrobial and toxicity studies of the aqueous extract of Ananas comosus (pineapple) crown leaf

Phytochemical characterization, anti-diarrhoeal, analgesic, anti-inflammatory activities and toxicity profile of Ananas comosus (L.) Merr (pineapple) leaf in albino rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ananas comosus (pineapple) leaf is used in ethnomedicine to treat diarrhoea, inflammation, pain, bacterial infections and oedema.

AIM OF THE STUDY

The aim of this study was to investigate the anti-diarrhoeal, anti-inflammatory and analgesic effects as well as the toxicity profile of the aqueous Ananas comosus leaf extract (AACLE) in rats.

METHODS

Methanol ACLE was subjected to gas chromatography-mass spectrometry (GC-MS) analysis. In the acute toxicity study, a single oral dose of up to 5000 mg/kg AACLE was administered. In the subacute toxicity study (28 days), rats in groups 2-4 received AACLE orally. The anti-diarrhoeal effect was studied using charcoal meal and castor oil-induced diarrhoea. Anti-inflammatory and analgesic tests were measured using egg albumin-induced paw oedema and acetic acid-induced writhing methods, respectively. For the subacute toxicity, anti-diarrhoeal, analgesic, and anti-inflammatory studies, AACLE was administered orally to rats at doses of 200, 400, and 600 mg/kg body weight.

RESULTS

Hexadecanoic acid methyl ester, 2-methoxy-4-vinylphenol, n-hexadecanoic acid and n-heptadecanol-1 were identified among other compounds with known pharmacological activities by GC-MS analysis. No deaths, behavioural changes, or signs of toxicity were observed in the acute toxicity study. Treatment with AACLE (28 days) decreased aspartate aminotransferase, alanine transaminase, total cholesterol, triglycerides, and low-density lipoprotein cholesterol, while high-density lipoprotein cholesterol, glutathione, and catalase increased when compared with control (P < 0.05). Treatment with AACLE did not cause significant changes in haematological or renal function parameters. Treatment with AACLE inhibited gastrointestinal motility and castor oil-induced diarrhoea in rats. Treatment with AACLE resulted in a dose-dependent (200-600 mg/kg) significant (P < 0.05) anti-diarrhoeal, analgesic, and anti-inflammatory effect compared to standard drugs.

CONCLUSION

Our study revealed that ACLE is not toxic but contains bioactive compounds with anti-diarrhoeal, anti-inflammatory, antimicrobial, and hepatoprotective activity. AACLE has antidiarrhoeal, analgesic and anti-inflammatory activity in rats, which justifies its therapeutic use in traditional medicine.

Diosmin and Bromelain Stimulate Glutathione and Total Thiols Production in Red Blood Cells

Diosmin and bromelain are bioactive compounds of plant origin with proven beneficial effects on the human cardiovascular system. We found that diosmin and bromelain slightly reduced total carbonyls levels and had no effect on TBARS levels, as well as slightly increased the total non-enzymatic antioxidant capacity in the RBCs at concentrations of 30 and 60 µg/mL. Diosmin and bromelain induced a significant increase in total thiols and glutathione in the RBCs. Examining the rheological properties of RBCs, we found that both compounds slightly reduce the internal viscosity of the RBCs. Using the MSL (maleimide spin label), we revealed that higher concentrations of bromelain led to a significant decrease in the mobility of this spin label attached to cytosolic thiols in the RBCs, as well as attached to hemoglobin at a higher concentration of diosmin, and for both concentrations of bromelain. Both compounds tended to decrease the cell membrane fluidity in the subsurface area, but not in the deeper regions. An increase in the glutathione concentration and the total level of thiol compounds promotes the protection of the RBCs against oxidative stress, suggesting that both compounds have a stabilizing effect on the cell membrane and improve the rheological properties of the RBCs.

Pineapple by-products as a source of bioactive compounds with potential for industrial food application

Pineapple is a tropical fruit consumed fresh or processed into various food products. However, the peel and crown of this fruit are not industrially exploited, thus generating tons of by-products that represent an economic and environmental concern. In order to promote the upcycling of these by-products, this work aimed to characterize the phenolic profile of its hydroethanolic extracts obtained from pineapple peel and crown leaves and to evaluate their in vitro bioactivity. The HPLC-DAD-ESI/MS analysis allowed the identification of 25 phenolic compounds, including phenolic acids and flavonoids. The antioxidant, cytotoxic, and antimicrobial activity assays highlighted the peel extract as the most promising and, therefore, it was incorporated into a traditional Portuguese pastry cake as a functional ingredient. The nutritional parameters of the developed food were not affected by the incorporation of the extract, but it promoted the antioxidant activity during its shelf-life. Overall, pineapple peel and crown appeared as promising by-products to be exploited by the food industry, which can be achieved through a circular economy approach.

A Systematic Review of Medicinal Plants of Kenya used in the Management of Bacterial Infections

Kenya’s vision 2030 partly aims at ensuring adequate health care for all, and the integration of traditional healthcare practices into the national healthcare system would present a more rapid alternative towards the realization of universal health coverage in Kenya. Currently, research on Kenyan medicinal plants with potential antibacterial activity remains vastly fragmented across numerous literature studies and databases; thus, it is imperative to collate and appraise these data for the ease of future research and possible clinical application. Objective. This review aims at exploring and compiling research evidence on medicinal plants used in the management of bacterial infections in Kenya, with a focus on their efficacy and safety. Methodology. A comprehensive web-based systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was executed to highlight the Kenyan medicinal plants used for the management of bacterial infections in Kenya. This review includes studies published until January 2021 from the PubMed, Science Direct, AJOL, and Google Scholar databases. Results. A total of 105 Kenyan medicinal plants belonging to 43 families have their in vitro activity against various human pathogenic bacteria evaluated. Plants from the Lamiaceae, Rutaceae, and Fabaceae families were the most commonly studied. Aloe secundiflora, Toddalia asiatica, Senna didymobotrya, Warbugia ugandensis, Tithonia diversifolia, Fuerstia africana, Olea africana, and Harrisonia abyssinica were the plants frequently evaluated within Kenya. The plants with the strongest antimicrobial activities were Toddalia asiatica, Hagenia abyssinica, Ocimum gratissimum, Harrisonia abyssinica, Senna didymobotrya, Olea Africana, Camellia sinensis, and Tarmarindus indica. Conclusion. Based on a published work, it is evident that traditional medicine is seemingly an acceptable and efficient system among Kenyan communities in the management of bacterial infections. Kenya’s rich biodiversity with diverse secondary metabolites presents a promising source of new therapeutic alternatives with possibly different mechanisms of action against bacteria.

Cosmeceutical Potential of Major Tropical and Subtropical Fruit By-Products for a Sustainable Revalorization

The increasing production of tropical fruits followed by their processing results in tons of waste, such as skins or seeds. However, these by-products have been reported to be rich in bioactive compounds (BACs) with excellent properties of interest in the cosmeceutical industry: antioxidant, anti-aging, anti-inflammatory, antimicrobial and photoprotective properties. This review summarizes the tropical fruits most produced worldwide, their bioactive composition and the most important and studied therapeutic properties that their by-products can contribute to skin health, as well as the different approaches for obtaining these compounds using techniques by conventional (Soxhlet, liquid-liquid extraction or maceration) and non-conventional extractions (supercritical fluid extraction (SFE), ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), pressurized liquid extraction (PLE) and two-phase aqueous system), followed by their identification by HPLC-MS or GC-MS analysis. Moreover, this work encompasses several studies that may prove the effects of seeds and skins from tropical fruits against oxidative stress, hyperpigmentation, acne, aging or UV radiation. Therefore, the investigation of functional components present in tropical fruit by-products under a circular bioeconomy model could be of great interest for the cosmeceutical industry and a very promising option for obtaining new cosmeceutical formulations.

Traditional medicinal plants used for treating emerging and re-emerging viral diseases in northern Nigeria

Introduction

For decades, viral diseases have been treated using medicinal plants and herbal practices in the northern part of Nigeria. Though scarcely investigated, these medicinal plants could serve as potential sources for novel antiviral drugs against emerging and remerging viral diseases. Therefore, this study is aimed at investigating the medicinal practices and plants used to treat emerging and re-emerging viral diseases including hepatitis, poliomyelitis, monkeypox, smallpox, yellow fever, Lassa fever, meningitis, and COVID-19 in some northern states; Katsina, Kebbi, Kwara and Sokoto states.

Method

Administered questionnaires and oral interviews were used to collect information on medicinal plants, method of preparation of herbal formulations, diagnosis, and treatment of viral diseases. Medicinal plants were collected, botanically identified, and assigned voucher numbers. The plant names were verified using www.theplantlist.org, www.worldfloraonline.org and the international plant names index.

Result

A total of 280 participating herbal medicine practitioners (HMPs) mentioned 131 plants belonging to 65 families. Plant parts such as roots, bark, leaf, seed, and fruit were prepared as a decoction, concoction, infusion, or ointment for oral and topical treatment of viral diseases. Moringa oleifera (75.3%), Elaeis guineensis Jacq. (80%), and Acacia nilotica (70%) were the most frequently mentioned plants in Kebbi, Kwara and Sokoto states, respectively.

Conclusion

The study revealed scarcely investigated and uninvestigated medicinal plants used to treat hepatitis, poliomyelitis, monkeypox, smallpox, yellow fever, Lassa fever, meningitis, and COVID-19. Future studies should be conducted to determine the antiviral potency and isolate novel bioactive agents from these plants against viral diseases.

Bromelain and Nisin: The Natural Antimicrobials with High Potential in Biomedicine

Infectious diseases along with various cancer types are among the most significant public health problems and the leading cause of death worldwide. The situation has become even more complex with the rapid development of multidrug-resistant microorganisms. New drugs are urgently needed to curb the increasing spread of diseases in humans and livestock. Promising candidates are natural antimicrobial peptides produced by bacteria, and therapeutic enzymes, extracted from medicinal plants. This review highlights the structure and properties of plant origin bromelain and antimicrobial peptide nisin, along with their mechanism of action, the immobilization strategies, and recent applications in the field of biomedicine. Future perspectives towards the commercialization of new biomedical products, including these important bioactive compounds, have been highlighted.

Antimicrobial Effect of Phytochemicals from Edible Plants

Current strategies of combating bacterial infections are limited and involve the use of antibiotics and preservatives. Each of these agents has generally inadequate efficacy and a number of serious adverse effects. Thus, there is an urgent need for new antimicrobial drugs and food preservatives with higher efficacy and lower toxicity. Edible plants have been used in medicine since ancient times and are well known for their successful antimicrobial activity. Often photosensitizers are present in many edible plants; they could be a promising source for a new generation of drugs and food preservatives. The use of photodynamic therapy allows enhancement of antimicrobial properties in plant photosensitizers. The purpose of this review is to present the verified data on the antimicrobial activities of photodynamic phytochemicals in edible species of the world’s flora, including the various mechanisms of their actions.

Protein extract of Bromelia karatas L. rich in cysteine proteases (ananain- and bromelain-like) has antibacterial activity against foodborne pathogens Listeria monocytogenes and Salmonella Typhimurium

Bromelia karatas L. is a plant species from the Americas. The presence of proteases in fruits of B. karatas has been reported but scarcely studied in detail. Proteolytic enzymes from Ananas comosus have displayed antifungal and antibacterial activity. Thus, novel proteases present in B. karatas may be useful as a source of compounds against microorganisms in medicine and food production. In this work, the protein extract from the fruits of B. karatas was characterized and its antibacterial activity against Salmonella Typhimurium and Listeria monocytogenes was determined for the first time. Proteins highly similar to ananain and the fruit bromelain from A. comosus were identified as the main proteases in B. karatas fruits using liquid chromatography with tandem mass spectrometry (LC-MS/MS). The soluble protein extract (SPE) at a concentration of 2.0 mg/mL displayed up to 80% of antibacterial activity against S. Typhimurium. Complete inhibition of L. monocytogenes was reached with up to 1.65 mg/mL of SPE. Plant protease extract containing ananain-like enzyme inhibited up to 90% against S. Typhimurium and up to 85% against L. monocytogenes using only 10 μg/mL of the partial-purified enzyme.

Collagenase Activity of Bromelain Immobilized at Gold Nanoparticle Interfaces for Therapeutic Applications

Bromelain (Bro) is a multiprotein complex extracted from the pineapple plant Ananas comosus, composed of at least eight cysteine proteases. Bro has a wide range of applications in medicine and industry, where the stability of its active proteases is always a major concern. The present study describes the improvement of stability and gain of specific activity in the enzymatic content of Bro immobilized on gold nanoparticles (GNPs). GNPs were synthesized in situ using Bro as the reducing and stabilizing agents and characterized by surface plasmon resonance and transmission electron microscopy. Consistent with the structural changes observed by circular dichroism analysis, the association with GNPs affected enzyme activity. The active Bro immobilized on GNPs (NanoBro) remained stable under storage and gained thermal stability consistent with a thermophilic enzyme. Proteolytic assays were performed on type I collagen membranes using fluorescence spectroscopy of O-phthaldialdehyde (OPA), changes in the membrane superficial structure, and topography by scanning electron microscopy, FTIR, and scanning laser confocal microscopy. Another characteristic of the NanoBro observed was the significant increase in susceptibility to the inhibitory effect of E-64, indicating a gain in cysteine protease activity. The higher stability and specific activity of NanoBro contributed to the broadening and improvement of Bro applications.

In vitro performance of free and encapsulated bromelain

For centuries, bromelain has been used to treat a range of ailments, even though its mechanism of action is not fully understood. Its therapeutic benefits include enzymatic debridement of the necrotic tissues of ulcers and burn wounds, besides anti-inflammatory, anti-tumor, and antioxidant properties. However, the protease is unstable and susceptible to self-hydrolysis over time. To overcome the stability issues of bromelain, a previous study formulated chitosan-bromelain nanoparticles (C-B-NP). We evaluated the optimized nanoformulation for in vitro antioxidant, cell antiproliferative activities and cell migration/proliferation in the scratch assay, comparing it with free bromelain. The antioxidant activity of free bromelain was concentration and time-dependent; after encapsulation, the activity level dropped, probably due to the slow release of protein from the nanoparticles. In vitro antiproliferative activity was observed in six tumor cell lines for free protein after 48 h of treatment (glioma, breast, ovarian, prostate, colon adenocarcinoma and chronic myeloid leukemia), but not for keratinocyte cells, enabling its use as an active topical treatment. In turn, C-B-NP only inhibited one cell line (chronic myeloid leukemia) and required higher concentrations for inhibition. After 144 h treatment of glioma cells with C-B-NP, growth inhibition was equivalent to that promoted by the free protein. This last result confirmed the delayed-release kinetics of the optimized formulation and bromelain integrity. Finally, a scratch assay with keratinocyte cells showed that C-B-NP achieved more than 90% wound retraction after 24 h, compared to no retraction with the free bromelain. Therefore, nanoencapsulation of bromelain with chitosan conferred physical protection, delayed release, and wound retraction activity to the formulation, properties that favor topical formulations with a modified release. In addition, the promising results with the glioma cell line point to further studies of C-B-NP for anti-tumor treatments.

A Systematic Review on Comparative Analysis, Toxicology, and Pharmacology of Medicinal Plants Against Haemonchus contortus

Background:Haemonchus contortus is an important pathogenic nematode parasite and major economic constraint of small ruminants in tropics and subtropics regions. This review is an attempt to systematically address the; (a) efficacy of different plants against H. contortus by in vitro and in vivo proof; (b) toxicology, mechanism of action, and active phyto-compounds involve in anti-haemonchiasis activity; (c) and comparative analysis of plant species evaluated both in vitro and in vivo.

Methods: Online databases (Google Scholar, PubMed, Scopus, and ScienceDirect) were searched and published research articles (1980–2020) were gathered and reviewed.

Results: A total of 187 plant species were reported belonging to 59 families and 145 genera with Asteraceae and Fabaceae being frequently used. Out of the total plant species, 171 species were found to be evaluated in vitro and only 40 species in vivo. Twenty-four species were commonly evaluated for in vitro and in vivo anti-haemonchiasis activity. Among the reported assays, egg hatching test (EHT) and fecal egg count reduction (FECR) were the most widely used assays in vitro and in vivo, respectively. Moreover, sheep were the frequently used experimental model in vivo. After comparative analysis, Lachesiodendron viridiflorum, Corymbia citriodora, Calotropis procera, and Artemisia herba-alba were found highly effective both in vitro and in vivo. L. viridiflorum inhibited enzymatic activities and metabolic processes of the parasite and was found to be safe without toxic effects. C. citriodora was moderately toxic in vivo, however, the plant extract produced promising nematicidal effects by causing muscular disorganization and changes in the mitochondrial profile. Additionally, C. procera and A. herba-alba despite of their high anti-haemonchiasis activity were found to be highly toxic at the tested concentrations. C. procera caused perforation and tegumental disorganization along with adult worm paralysis. Nineteen compounds were reported, among which anethole and carvone completely inhibited egg hatching in vitro and significantly reduced fecal egg count, decreased male length, and reproductive capacity of female in vivo.

Conclusion: This review summarized different medicinal plants owing to nematicidal activities against H. contortus eggs, larvae, and adult worms. Plants like L. viridiflorum, C. citriodora, C. procera, and A. herba-alba, while compounds anethole and carvone having promising nematicidal activities and could be an alternative source for developing novel drugs after further investigation.

Revalorization of bioactive compounds from tropical fruit by-products and industrial applications by means of sustainable approaches

Tropical fruits trade is on the rise due to the claimed health benefits related with their consumption. Functional activities are exerted by the presence of bioactive compounds which could be used for prevention or amelioration diseases. However, the occurrence of bioactive compounds is found mainly in non-edible fraction of tropical fruits which are usually discarded. Therefore, the revalorization of tropical fruits by-products as source of functional compounds is on the cutting-edge research. The implementation of this challenge not only allows the enhancement of the tropical fruits by-products management, but also the production of value-added products. This review compiles the latest comprehensive information about the revalorization of bioactive compounds from tropical fruits by-products. A revision of the sustainable green technologies used for the isolation of valuable compounds has been carried out as well as the current food, functional, cosmeceutical and bioenergetics industrial applications of bioactive compounds extracted from tropical fruits by-products.

Mycotoxins from Fusarium proliferatum: new inhibitors of papain-like cysteine proteases

Papain-like cysteine proteases (PLCPs) in plants are essential to prevent phytopathogen invasion. In order to search for cysteine protease inhibitors and to investigate compounds that could be associated to pineapple Fusarium disease, a chemistry investigation was performed on Fusarium proliferatum isolated from Ananas comosus (pineapple) and cultivated in Czapek medium. From F. proliferatum extracts, nine secondary metabolites were isolated and characterized by nuclear magnetic resonance spectroscopy and mass spectrometry experiments: beauvericin (1), fusaric acid (2), N-ethyl-3-phenylacetamide (3), N-acetyltryptamine (4), cyclo(L-Val-L-Pro) cyclodipeptide (5), cyclo(L-Leu-L-Pro) cyclodipeptide (6), cyclo(L-Leu-L-Pro) diketopiperazine (7), 2,4-dihydroxypyrimidine (8), and 1H-indole-3-carbaldehyde (9). Compounds 1, 3, and 6 showed significant inhibition of papain, with IC50 values of 25.3 ± 1.9, 39.4 ± 2.5, and 7.4 ± 0.5 μM, respectively. Compound 1 also showed significant inhibition against human cathepsins V and B with IC50 of 46.0 ± 3.0 and 6.8 ± 0.7 μM, respectively. The inhibition of papain by mycotoxins (fusaric acid and beauvericin) may indicate a mechanism of Fusarium in the roles of infection process.

Antimicrobial, antioxidant, volatile and phenolic profiles of cabbage-stalk and pineapple-crown flour revealed by GC-MS and UPLC-MSE

Unconventional parts of vegetables represent a rich source of health-promoting phytochemicals. The phenolic profile of cabbage-stalk flour (CSF), pineapple-crown flour (PCF), and their essential oils were characterized via UPLC-ESI-QTOF-MS^E and GC-FID/MS. Antimicrobial activity was tested against five strains, and antioxidant activities were determined in free and bound extracts. Globally, 177 phenolics were tentatively identified in PCF (major p-coumaric acid, ferulic acid, and 4-hydroxybenzaldehyde) and 56 in CSF (major chlorogenicacid, quercetin 3-O-glucuronide, and p-coumaric acid). PCF exhibited a distinguished profile (lignans, stilbenes) and antioxidant capacity, especially in bound extracts (1.3 g GAE.100 g^-1; 0.6 g catechin eq.100 g^-1; DPPH: 244.7; ABTS: 467.8; FRAP: 762.6 µg TE.g^-1, ORAC: 40.9 mg TE.g^-1). The main classes of volatile compounds were fatty acids, their esters, and terpenes in CSF (30) and PCF (41). A comprehensive metabolomic approach revealed CSF and PCF as a promising source of PC, showing great antioxidant and discrete antimicrobial activities.

Novel in-office peroxide-free tooth-whitening gels: bleaching effectiveness, enamel surface alterations, and cell viability

To evaluate the bleaching ability, the effect on enamel surface and cytotoxicity of novel tooth-whitening formulations containing papain, ficin, or bromelain. Forty bovine dental discs (6 cm ×4 cm) were pigmentated and randomly allocated into the following groups (n = 10): Group 1, 20 wt% carbamide peroxide (control); group 2, 1% papain-based whitening; group 3, 1% ficin-based whitening; and group 4, 1% bromelain-based whitening. The whitening gels were prepared and applied on the enamel three times per day once a week, for 4 weeks. Color measurement was obtained by CIEDE2000. Enamel Knoop microhardness and roughness were evaluated. The WST-1 assay was used to evaluate the cell viability of mouse fibroblast cells (L929). Data were statistically analyzed by one-way analysis of variance (ANOVA) and Student Newman Keuls's post hoc test at α = 0.05 significance level. Bromelain, ficin-based, and carbamide peroxide bleaching gels showed a similar color change (p < 0.001). Higher enamel hardness decrease and higher enamel roughness were caused by the carbamide peroxide (p < 0.05). The experimental whitening gels did not affect cell viability. Tooth bleaching gels containing bromelain, papain, or ficin have substantial clinical potential to be used in the development of peroxide-free tooth whitening gels.

Toxicity and anthelmintic efficacy of chitosan encapsulated bromelain against gastrointestinal strongyles in Small East African goats in Kenya

BACKGROUND AND AIM

The development of resistance to anthelmintic drugs has prompted research into alternative methods of controlling intestinal nematodes in ruminants. This study aimed at evaluating the in vitro and in vivo anthelmintic efficacy and toxicity of chitosan encapsulated bromelain in Small East African goats in Kenya.

MATERIALS AND METHODS

Adult mortality assay was performed using live Haemonchus contortus worms treated with encapsulated bromelain solution ranging from 0.125 mg/ml to 2 mg/ml. Percentage mortality of worms was calculated after 24 h and the lethal concentration 50% (LC50) determined. For the in vivo study, 18 healthy male indigenous goats were divided into six groups of three goats each. The encapsulated bromelain was orally administered in increasing dosages (3-30 mg kg) once daily, for 14 days. The packed cell volume (PCV), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, creatinine, and fecal egg count (FEC) were determined on a weekly basis. At the end of the study, the goats were sacrificed and gross pathology and histopathology of main organs assessed.

RESULTS

Albendazole had the highest (p<0.05) anthelmintic effect on the worms. An LC50 of 0.05 mg/ml, 0.445 mg/ml, and 0.155 mg/ml was observed for albendazole, plain bromelain, and encapsulated bromelain, respectively. The PCV of treated and untreated goats did not show any significant difference (p>0.05), varied from 29.3% to 35.1%, and was within the normal range of the animal. Likewise, no significant differences (p>0.05) were observed between the AST, ALT, urea, and creatinine levels of treated and the control (non-treated) goats. No adverse clinical symptoms, toxicity of the main organs, and mortality in goats were associated with the chitosan encapsulated bromelain after administration of dose up to 30 mg/kg for 14 days. Therefore, the lethal dose 50 of encapsulated bromelain may be considered to be >30 mg/kg. On day 28 post-treatment, the encapsulated bromelain showed a higher in vivo FEC reduction (68.8%) as compared to the plain bromelain (32.4%).

CONCLUSION

Our results show that bromelain encapsulated in chitosan may be safe and effective in reducing the burden of gastrointestinal tract strongyle nematodes in goats. However, there is a need for further studies to establish the dosage of the encapsulated bromelain to be administered in a single dose for the treatment of goats against gastrointestinal strongyles. In addition, species-specific studies on the efficacy of encapsulated bromelain on strongyles are necessary to evaluate its effectiveness against the entire Strongyloididae family.

Anti-cholinesterase potential of diverse botanical families from Malaysia: Evaluation of crude extracts and fractions from liquid-liquid extraction and acid-base fractionation

ETHNOPHARMACOLOGICAL RELEVANCE

Enhancement of cholinergic functions in the brain via acetylcholinesterase inhibition is one of the main therapeutic strategies to improve symptoms associated with Alzheimer's or related cognitive deficits. There is a pathophysiological correlation between Alzheimer's and Diabetes Mellitus, as well as inflammation and oxidative stress that may cause cognitive decline.

AIM OF THE STUDY

The present study was intended to evaluate anti-cholinesterase potential of 177 Malaysian plant extracts from 148 species known to have related ethnomedicinal uses such as anti-inflammatory, anti-oxidant, anti-diabetic, epilepsy, headache, memory enhancement and anti-aging.

MATERIALS AND METHODS

Anti-cholinesterase screening against both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes was performed on the basis of in-vitro colorimetric 96-well microplate-based assay method. Potent active plant extracts were subjected to liquid-liquid extraction and acid-base fractionation for further analysis.

RESULTS

Fifty-seven plant extracts exhibited potent anti-cholinesterase activities (50-100% inhibition) at 200 μg/ml. Majority of the active plants originated from Fabaceae family. Coccoloba uvifera (L.) L. stem extract manifested the lowest IC₅₀ of 3.78 μg/ml for AChE and 5.94 μg/ml for BChE. A few native species including Tetracera indica (Christm. & Panz.) Merr., Cyrtostachys renda Blume and Ixora javanica (Blume) DC. showed cholinesterase inhibition despite limited local medical applications. Further anti-AChE evaluation (50 μg/ml) of 18 potent plant extracts harbored active polar components in butanol and water fractions, except Senna pendula (Willd.) H.S.Irwin & Barneby (leaves and stems), Acacia auriculiformis Benth. (leaves), Artocarpus altilis (Parkinson ex F.A.Zorn) Fosberg (leaves), and Macaranga tanarius (L.) Mull.Arg. (leaves) that showed inhibitory activity in less polar fractions. The acidic extraction of these four plant species improved their inhibition level against AChE.

CONCLUSION

This study rendered a preliminary overview of anti-cholinesterase activity from diverse Malaysian botanical families in which provided the medical relevance toward these native plant species, especially ones with limited ethnobotanical record or practice.

Efficacy of proteolytic enzyme bromelain on health outcomes after third molar surgery. Systematic review and meta-analysis of randomized clinical trials

Background

Bromelain is a cysteine protease isolated from pineapple with a range of biological properties including platelet aggregation inhibition and anti-inflammatory effects. Recent studies have evaluated the clinical implications of bromelain in reducing postoperative inflammatory complications after third molar surgery, but the results are contrasting. This systematic review and meta-analysis evaluated the effects of bromelain on health outcomes in patients submitted to third molar surgery.

Material and Methods

The study was conducted following the PRISMA statement. Searches were conducted in six electronic databases and Google Scholar from inception to May 2018. The following elements were used to define eligibility criteria: (1) population: patients undergoing third molar surgery; (2) intervention and controls: bromelain vs placebo or no-treatment control group; (3) outcomes: quality of life, postoperative pain, rescue analgesic consumption, facial swelling, and trismus; and (4) study type: randomized clinical trials (RCTs). Treatment effects were defined as weighted (WMD) or standardized mean difference (SMD) and 95%CIs.

Results

Six RCTs were included in the meta-analysis. There was large effect size of bromelain on improving physical appearance (SMD -0.77, CI% 95 -1.11 to -0.42), social isolation (SMD -0.97, CI% 95 -1.74 to -0.21), and sleep quality (SMD -1.19, CI% 95 -1.97 to -0.40) during the first postoperative week. Differences in pain intensity were found during the first 24h (SMD -0.49, CI 95% -0.82 to -0.17) and 7 days after surgery (SMD -0.52, CI 95% -0.79 to -0.24). No evidence was found that bromelain was effective in reducing trismus and facial swelling.

Conclusions

The currently available evidence suggests that bromelain has a beneficial effect in reducing pain and has a positive impact on patient quality of life after third molar surgery. However, therapeutic advances for the use of bromelain need a high level of evidence and further head-to-head RCTs are needed to inform clinical choices.

Key words:Bromelain, third molar, oral surgical procedures.

Olea europaea small RNA with functional homology to human miR34a in cross-kingdom interaction of anti-tumoral response

Functional foods include compounds with nutritional and health properties. The human diet could play a stronger role in cancer prevention. Only a few studies have described the presence of plant small RNA, in humans who were fed with plant foods, which demonstrated the ability of these molecules to modulate consumer's genes and evidenced the existence of a plant-animal regulation. Through in silico prediction, Olea europaea small RNAs (sRs), which had been previously reported as miRNAs, were identified, each with functional homology to hsa-miR34a. According to this initial funding, we investigated the ability of oeu-sRs to regulate tumorigenesis in human cells. The transfection of these synthetic oeu-sRs reduced the protein expression of hsa-miR34a mRNA targets, increased apoptosis and decreased proliferation in different tumor cells; by contrast, no effect was observed in PBMCs from healthy donors. The introduction of oeu-small RNA in hsa-miR34a-deficient tumor cells restores its function, whereas cells with normal expression of endogenous hsa-miR34a remained unaffected. The natural oeu-small RNAs that were extracted from O. europaea drupes induce the same effects as synthetic sRs. Careful research on the small RNA sequences executed for mapping and annotation in the genome of O. europaea var. Sylvestris and var. Farga led to the hypothesis that RNA fragments with functional homology to human miRNAs could be generated from the degradation of regions of RNA transcripts. These results indicate the possibility of developing novel natural non-toxic drugs that contain active plant-derived tumor-suppressing small RNA with functional homology to hsa-miRNAs and that can support antineoplastic strategies.

Natural actives for wound healing: A review

Nature has been a source of medicinal treatments for thousands of years, with the use of plants as prototypes for drug development and for the extraction of active compounds. Skin injuries occur regularly in everyday life, and the human skin has the ability to promote repair spontaneously under healthy conditions. However, some intrinsic and external factors may interfere with skins' natural ability, leading to nonhealing lesions and chronic wounds, which directly affect health and quality of life. Thus, attention should be given to this health problem, using an appropriated management when necessary. In this scenario, phytotherapy may be an option for cutaneous wound treatment, although further high-quality studies are needed to firmly establish the clinical efficacy of plants. This article reviews traditionally used natural actives for wound healing, highlighting their characteristics and mode of action.

Efficacy of Aloe vera, Ananas comosus, and Sansevieria masoniana Cream on the Skin Wound Infected with MRSA

The tropical area has a lot of herbal medicines such as Aloe vera (AV), Ananas comosus (AC), and Sansevieria masoniana (SM). All the three have a unique potential effect as an antibacterial and wound-healing promoter. The aim of this study is to explore the role of AV, AC, and SM on the skin wound infected with methicillin-resistant Staphylococcus aureus (MRSA). Forty-five adult female Sprague Dawley rats weighing 250–300 grams were divided into 5 groups. All the groups were exposed to two round full-thickness punch biopsy and infected with MRSA. The group C was the control group/untreated; group BC was treated with base cream/without extract; group AV was treated with 75% AV cream; group AC was treated with 75% AC cream, and group SM was treated with 75% SM cream. The wounds were observed on days 5, 10, and 15. The healing of skin wounds was measured by a percentage of closure, skin tensile strength, and histopathology. The result showed that AV, AC, and SM have a similar potential effect on healing in the wound that was infected with MRSA compared to the groups C and BC (P < 0.05). It shows that all the three herbal formulations can be used as the alternative therapy to the wound infected with MRSA.

The interaction of silver nanoparticles with papain and bromelain

These fundamental studies will provide some new insights into the safe and effective application of AgNPs in biological and medical areas.

Bacterial Nanocellulose Loaded with Bromelain: Assessment of Antimicrobial, Antioxidant and Physical-Chemical Properties

Bacterial nanocellulose (BNC) has desirable properties for wound healing such as high purity, good shape retention, and high water binding capacity. Bromelain is a protease found in pineapple tissues and has been applied in several fields, it has anti-inflammatory and anticancer properties, promotes cell apoptosis, amongst others. In this work, a BNC based device for the controlled release of bromelain was developed. BNC were submersed in sterilized bromelain solution and incubated at 25 °C under 100 rpm for 24 h. Physical-chemical properties, protein concentration, antioxidant and antimicrobial activities were measured. Results demonstrate that BNC could improve bromelain antimicrobial activity 9 times. Those findings allow concluding that bromelain is a promising molecule to be incorporated into BNC’s. The BNC’s characteristics seem to represent a new promising delivery system of the loaded biomolecule, and protected from external actions.

The biochemical characterization, stabilization studies and the antiproliferative effect of bromelain against B16F10 murine melanoma cells

The current study aims to extract bromelain from different parts (stem, crown, peels, pulp and leaves) of Ananas comosus var. comosus AGB 772; to determine of optimum pH and temperature; to test bromelain stability in disodium EDTA and sodium benzoate, and to investigate its pharmacological activity on B16F10 murine melanoma cells in vitro. The highest enzymatic activity was found in bromelain extracted from the pulp and peel. The optimum bromelain pH among all studied pineapple parts was 6.0. The optimum temperature was above 50 °C in all bromelain extracts. The fluorescence analysis confirmed the stability of bromelain in the presence of EDTA and sodium benzoate. Bromelain was pharmacologically active against B16F10 melanoma cells and it was possible verifying approximately 100% inhibition of tumor cell proliferation in vitro. Since bromelain activity was found in different parts of pineapple plants, pineapple residues from the food industry may be used for bromelain extraction.

Combination of cisplatin and bromelain exerts synergistic cytotoxic effects against breast cancer cell line MDA-MB-231 in vitro

Background

Bromelain, which is a cysteine endopeptidase commonly found in pineapple stems, has been investigated as a potential anti-cancer agent for the treatment of breast cancer. However, information pertaining to the effects of combining bromelain with existing chemotherapeutic drugs remains scarce. This study aimed to investigate the possible synergistic cytotoxic effects of using bromelain in combination with cisplatin on MDA-MB-231 human breast cancer cells.

Method

MDA-MB-231 cells were treated with different concentrations (0.24–9.5 µM) of bromelain or cisplatin alone, as well as four different combinations of these two agents to assess their individual and combination effects after 24 and 48 h. Cell viability was analyzed using an MTT assay. The induction of apoptosis was assessed using cell cycle analysis and an Annexin V-FITC assay. The role of the mitochondrial membrane potential in the apoptotic process was assessed using a JC-1 staining assay. Apoptotic protein levels were assessed by western blot analysis and proteome profiling using an antibody array kit.

Results

Single-agent treatment with cisplatin or bromelain led to dose- and time-dependent decreases in the viability of the MDA-MB-231 cells at 24 and 48 h. Furthermore, most of the combinations evaluated in this study displayed synergistic effects against MDA-MB-231 cells at 48 h, with combination 1 (bromelain 2 µM + cisplatin 1.5 µM) exhibiting the greatest synergistic effect (P = 0.000). The results of subsequent assays indicated that combination 1 treatment induced apoptosis via mitochondria-mediated pathway. Combination 1 also resulted in significant decreases in the levels of several apoptotic proteins such as Bcl-x and HSP70, compared with bromelain (P = 0.002 and 0.000, respectively) or cisplatin (P = 0.000 and 0.001, respectively) single treatment. Notably, MDA-MB-231 cells treated with combination 1 showed increased levels of the pro-apoptotic proteins Bax compared with those treated with bromelain (P = 0.000) or cisplatin single treatment (P = 0.043).

Conclusion

Bromelain in combination with cisplatin synergistically enhanced the induction of apoptosis in MDA-MB-231 cells.

Acute and sub-chronic (28 days) oral toxicity evaluation of tincture Baccharis trimera (Less) Backer in male and female rodent animals

The infusion of Baccharis trimera (Less) DC, popularly known as "carqueja" (broom), is popularly used in the treatment of hepatic and digestive problems. In this study, we evaluated the acute and sub-chronic oral toxicities of B. trimera tincture on male and female Wistar rats according to Organization for Economic Cooperation and Development (OECD, guidelines 423 e 407, respectively). The B. trimera tincture was administered by oral gavage in a single dose (2000 mg/kg) in doses of 100, 200 and 400 mg/kg daily for 28 days. Blood was collected to analyze hematological and biochemical parameters. Kidneys and liver were homogenized to determine lipid peroxidation and δ-aminolevulinate dehydratase (δ-ALA-D) and catalase (CAT) enzyme activities. In acute treatment, tincture did not induce any signs of toxicity or mortality. Daily oral administration produced no significant changes in the hematological and biochemical parameters, except for the hepatic enzymes alanine aminotransferase (ALAT) and aspartate aminotransferase (ASAT) that showed a reduction in both sexes. Moreover, the B. trimera tincture did not increase lipid peroxidation or affected ALA-D and CAT activities. In conclusion, the tincture of B. trimera may be considered relatively safe in this protocol.