Aloe Genus Plants: From Farm to Food Applications and Phytopharmacotherapy

Ethnobotany and phytochemistry of plants used to treat musculoskeletal disorders among Skaw Karen, Thailand

CONTEXT

Musculoskeletal system disorders (MSD) are prevalent around the world affecting the health of people, especially farmers who work hard in the field. Karen farmers use many medicinal plants to treat MSD.

OBJECTIVE

This study collects traditional plant-based remedies used by the Skaw Karen to treat MSD and evaluates their active phytochemical compounds.

MATERIALS AND METHODS

The ethnobotanical study was conducted in six Karen villages in Chiang Mai province using semi-structured interviews were of 120 informants. The data were analyzed using ethnobotanical indices including use values (UV), choice value (CV), and informant consensus factor (ICF). Consequently, the 20 most important species, according to the indices, were selected for phytochemical analysis using LC-MS/MS.

RESULTS

A total of 3731 use reports were obtained for 139 species used in MSD treatment. The most common ailments treated with those plants were muscular pain. A total of 172 high-potential active compounds for MSD treatment were identified. Most of them were flavonoids, terpenoids, alkaloids, and steroids. The prevalent phytochemical compounds related to treat MSD were 9-hydroxycalabaxanthone, dihydrovaltrate, morroniside, isoacteoside, lithocholic acid, pomiferin, cucurbitacin E, leonuriside A, liriodendrin, and physalin E. Sambucus javanica Reinw. ex Blume (Adoxaceae), Betula alnoides Buch.-Ham. ex D.Don (Betulaceae), Blumea balsamifera (L.) DC. (Asteraceae), Plantago major L. (Plantaginaceae) and Flacourtia jangomas (Lour.) Raeusch. (Salicaceae) all had high ethnobotanical index values and many active compounds.

DISCUSSION AND CONCLUSIONS

This study provides valuable information, demonstrating low-cost medicine plants that are locally available. It is a choice of treatment for people living in remote areas.

Antibacterial and Antioxidant Compounds from the Root Extract of Aloe debrana

This study was conducted to isolate and identify the chemical compounds from the roots of Aloe debrana (L.) and evaluate their antioxidant and antibacterial activities. From the acetone (99.5%) extract of the roots of this plant, four anthraquinones, such as chrysophanol (1), asphodeline (2), aloesaponarin I (5), and laccaic acid D-methyl ester (6), and a new catechol derivative, 5-allyl-3-methoxybenzene-1,2-diol (3), were isolated and elucidated by different chromatographic and spectroscopic methods together with linoleic acid (4), respectively. Compounds 2, 3, and 4 were reported here for the first time from this plant and compound 3 from the genus Aloe. The compounds were evaluated for their antioxidant activity using H2O2 and DPPH assays and bactericidal activity against S. aureus and E. coli. Compounds 3 and 6 showed highest antioxidant activities with IC50 values of 19.38 ± 0.64 and 32.81 ± 0.78 μg/mL in DPPH, and 28.52 ± 1.08 and 27.31 ± 1.46 μg/mL in H2O2, respectively. The isolated compounds also demonstrated considerable activity towards S. aureus. Among these compounds, compound 3 exhibited the highest activity (91.20 ± 0.12% and 9.14 ± 0.93 mm at 1.0 mg/mL) against this bacterium. The overall results suggest that the isolated compounds may be considered as potential sources of the bioactive agents to be used in the pharmacological, food, and other industries. Moreover, their high sensitivity against S. aureus may also support the use of A. debrana plant in the traditional medicine to treat wounds. Therefore, the isolated compounds are responsible for medicinal properties of this plant.

New opportunities and perspectives on biosynthesis and bioactivities of secondary metabolites from Aloe vera

Historically, the genus Aloe has been an indispensable part of both traditional and modern medicine. Decades of intensive research have unveiled the major bioactive secondary metabolites of this plant. Recent pandemic outbreaks have revitalized curiosity in aloe metabolites, as they have proven pharmacokinetic profiles and repurposable chemical space. However, the structural complexity of these metabolites has hindered scientific advances in the chemical synthesis of these compounds. Multi-omics research interventions have transformed aloe research by providing insights into the biosynthesis of many of these compounds, for example, aloesone, aloenin, noreugenin, aloin, saponins, and carotenoids. Here, we summarize the biological activities of major aloe secondary metabolites with a focus on their mechanism of action. We also highlight the recent advances in decoding the aloe metabolite biosynthetic pathways and enzymatic machinery linked with these pathways. Proof-of-concept studies on in vitro, whole-cell, and microbial synthesis of aloe compounds have also been briefed. Research initiatives on the structural modification of various aloe metabolites to expand their chemical space and activity are detailed. Further, the technological limitations, patent status, and prospects of aloe secondary metabolites in biomedicine have been discussed.

Deciphering the crosstalk between inflammation and biofilm in chronic wound healing: Phytocompounds loaded bionanomaterials as therapeutics

In terms of the economics and public health, chronic wounds exert a significant detrimental impact on the health care system. Bacterial infections, which cause the formation of highly resistant biofilms that elude standard antibiotics, are the main cause of chronic, non-healing wounds. Numerous studies have shown that phytochemicals are effective in treating a variety of diseases, and traditional medicinal plants often include important chemical groups such alkaloids, phenolics, tannins, terpenes, steroids, flavonoids, glycosides, and fatty acids. These substances are essential for scavenging free radicals which helps in reducing inflammation, fending off infections, and hastening the healing of wounds. Bacterial species can survive in chronic wound conditions because biofilms employ quorum sensing as a communication technique which regulates the expression of virulence components. Fortunately, several phytochemicals have anti-QS characteristics that efficiently block QS pathways, prevent drug-resistant strains, and reduce biofilm development in chronic wounds. This review emphasizes the potential of phytocompounds as crucial agents for alleviating bacterial infections and promoting wound healing by reducing the inflammation in chronic wounds, exhibiting potential avenues for future therapeutic approaches to mitigate the healthcare burden provided by these challenging conditions.

Aloe vera gel relieves cadmium triggered hepatic injury via antioxidative, anti-inflammatory, and anti-apoptotic routes

Aloe vera (AV) gel extracted from fresh AV leaves was chosen in this study to evaluate its antioxidant, anti-inflammatory, and antiapoptotic activities against cadmium (Cd) -induced liver injury. Forty Wistar male adult rats were equally divided into four groups. Group I (standard control) ingested with 2.5 ml/kg b.w. of physiological saline. Group II (Cd-intoxicated) received 3 mg/kg b.w./day of CdCl2 dissolved in saline. Group III (AV) received 200 mg/kg b.w./day of AV gel dissolved in saline. Group IV (Cd+AV) ingested with 200 mg/kg b.w./day of AV gel solution along with 3 mg/kg b.w. CdCl2. All groups were ingested orally by gavage for 3 consecutive weeks. Paraoxonase-1 (PON-1) and HSP70 were measured in serum. The deposited Cd level, nitric oxide content, lipid peroxidation, collagen-1 (COL-1), and metalloproteinase-9 (MMP-9) levels were all determined in liver tissue homogenates. Gene expression of NF-κB and IL-6, Bax, and Bcl2, as well as immunohistochemistry analysis of activated caspase-3, was performed. Results showed that ingestion of AV gel greatly relieved all oxidative stress due to Cd exposure, modulated the NF-κB, IL-6, Bax, and Bcl2 expression levels, and improved the apoptotic state. In conclusion, AV gel confirmed its potential ameliorating effect against liver injury induced due to Cd exposure.

Anthraquinones against Cryptococcus neoformans sensu stricto: antifungal interaction, biofilm inhibition and pathogenicity in the Caenorhabditis elegans model

Introduction. Cryptococcal biofilms have been associated with persistent infections and antifungal resistance. Therefore, strategies, such as the association of natural compounds and antifungal drugs, have been applied for the prevention of biofilm growth. Moreover, the Caenorhabditis elegans pathogenicity model has been used to investigate the capacity to inhibit the pathogenicity of Cryptococcus neoformans sensu stricto.Hypothesis. Anthraquinones and antifungals are associated with preventing C. neoformans sensu stricto biofilm formation and disrupting these communities. Antraquinones reduced the C. neoformans sensu stricto pathogenicity in the C. elegans model.Aim. This study aimed to evaluate the in vitro interaction between aloe emodin, barbaloin or chrysophanol and itraconazole or amphotericin B against growing and mature biofilms of C. neoformans sensu stricto.Methodology. Compounds and antifungal drugs were added during biofilm formation or after 72 h of growth. Then, the metabolic activity was evaluated by the MTT reduction assay, the biomass by crystal-violet staining and the biofilm morphology by confocal laser scanning microscopy. C. neoformans sensu stricto's pathogenicity was investigated using the nematode C. elegans. Finally, pathogenicity inhibition by aloe emodin, barbarloin and chrysophanol was investigated using this model.Results. Anthraquinone-antifungal combinations affected the development of biofilms with a reduction of over 60 % in metabolic activity and above 50 % in biomass. Aloe emodin and barbaloin increased the anti-biofilm activity of antifungal drugs. Chrysophanol potentiated the effect of itraconazole against C. neoformans sensu stricto biofilms. The C. elegans mortality rate reached 76.7 % after the worms were exposed to C. neoformans sensu stricto for 96 h. Aloe emodin, barbaloin and chrysophanol reduced the C. elegans pathogenicity with mortality rates of 61.12 %, 65 % and 53.34 %, respectively, after the worms were exposed for 96 h to C. neoformans sensu stricto and these compounds at same time.Conclusion. These results highlight the potential activity of anthraquinones to increase the effectiveness of antifungal drugs against cryptococcal biofilms.

Chemical structures, biological activities, and medicinal potentials of amine compounds detected from Aloe species

Unrestricted interest in Aloe species has grown rapidly, and a lot of research is currently being done to learn more about the properties of the various Aloe constituents. Organic compounds containing amine as functional group are present in a vivid variety of compounds, namely, amino acids, hormones, neurotransmitters, DNA, alkaloids, dyes, etc. These compounds have amine functional groups that have various biological activities, which make them responsible for medicinal potential in the form of pharmaceutical, nutraceutical, and cosmeceutical applications. Consequently, the present review work provides an indication of the amines investigated in Aloe species and their therapeutic uses. Various amine compounds of the Aloe species have effective biological properties to treat diseases. Generally, the genus Aloe has various active amine-containing compounds to combat diseases when humans use them in various forms.

Biopolymer collagen-chitosan scaffold containing Aloe vera for chondrogenic efficacy on cartilage tissue engineering

The chondrogenic efficacy of aloe vera blended collagen-chitosan (COL-CS-AV) porous scaffold was investigated using articular chondrocytes in a standard condition. Cytocompatibility was analyzed using fluorescent dyes (calcein AM/ethidium bromide) and the viable cells were quantified by MTT assay. Glycosaminoglycan (GAG) content of ECM was estimated by using 1, 9-Dimethyl methylene Blue (DMMB). The total RNA content was quantified and the cartilage specific genes (col2a1, Acan) were amplified by reverse transcription-PCR from the cell lysate of the scaffolds. Histological examination was made using Haematoxylin and Eosin (H&E), safranin-O, masson's trichrome, alcian blue, and alizarin red to stain the specific component of ECM secreted on the construct. The cartilage specific collagen type II was estimated by immunohistochemistry using monoclonal type II collagen antibody. The results of these studies proved that COL-CS-AV scaffold has more chondrogenic efficacy than COL-CS, thus the aloe vera blend COL-CS-AV scaffold might be used as suitable candidate for cartilage tissue engineering.

Aloe adigratana Reynolds: Preliminary Phytochemical Screening, Proximate Content, Essential Oil Analysis, and In Vitro Antifungal Activity Studies of Its Leaf Peels and Gel

Background

Aloe species are among the most significant plants with several applications. Many of the species, however, are underexplored, owing to their scarcity and limited geographical distribution. A. adigratana Reynolds, which is common in Ethiopia, is one of the little-studied and endangered Aloe species.

Objective

This preliminary study focuses on the phytochemical screening, proximate analysis, essential oil content, and antifungal activities of A. adigratana leaf peels. Antifungal activities were also tested on the gels of the plant for comparison.

Methods

Standard procedures were used for phytochemical and proximate composition studies. Essential oil analysis was performed using a gas chromatography-mass spectrometry instrument. Using the well-diffusion method, investigations on antifungal activity were performed on three clinically isolated specimens of dandruff-causing fungus; namely, Malassezia furfur, Malassezia restricta, and Malassezia globosa.

Results

The leaf peels of A. adigratana contained alkaloids, flavonoids, tannins, and terpenes. The mean moisture, ash, and crude fat levels were 85.69, 92.20, and 8.00%, respectively, whereas the mean total protein and mean total carbohydrate values were 2.59 and 3.04%. Gas chromatography-mass spectrometry investigation confirmed the presence of fifteen essential oils. The most prevalent essential oil component was discovered to be phytol (33.78%), followed by decane (11.29%). In a dose-dependent way, the leaf latex and gel extracts prevented the growth of three dandruff-causing Malassezia fungal species (M. furfur, M. restricta, and M. globosa). Both the latex and gel demonstrated the maximum activity on M. globosa, the most prevalent fungus in the research area, with minimum inhibitory concentrations of 0.24 and 0.48 mg/mL and minimum fungicidal concentrations of 0.48 and 0.97 mg/mL, respectively.

Conclusion

In general, the proximate and essential oil compositions of A. adigratana leaves were comparable to those of other Aloe species widely used in the food, cosmetic, and pharmaceutical industries, implying that A. adigratana could be a potential future plant for such industries.

Aloe vera-Based Hydrogels for Wound Healing: Properties and Therapeutic Effects

Aloe vera-based hydrogels have emerged as promising platforms for the delivery of therapeutic agents in wound dressings due to their biocompatibility and unique wound-healing properties. The present study provides a comprehensive overview of recent advances in the application of Aloe vera-based hydrogels for wound healing. The synthesis methods, structural characteristics, and properties of Aloe vera-based hydrogels are discussed. Mechanisms of therapeutic agents released from Aloe vera-based hydrogels, including diffusion, swelling, and degradation, are also analyzed. In addition, the therapeutic effects of Aloe vera-based hydrogels on wound healing, as well as the reduction of inflammation, antimicrobial activity, and tissue regeneration, are highlighted. The incorporation of various therapeutic agents, such as antimicrobial and anti-inflammatory ones, into Aloe vera-based hydrogels is reviewed in detail. Furthermore, challenges and future prospects of Aloe vera-based hydrogels for wound dressing applications are considered. This review provides valuable information on the current status of Aloe vera-based hydrogels for the delivery of therapeutic agents in wound dressings and highlights their potential to improve wound healing outcomes.

A comparative evaluation of the antimicrobial effect of chamomile, Aloe vera-green tea, and chlorhexidine mouthwashes on some oral bacterial species

Background

Plant compounds such as Aloe vera, green tea, and chamomile have been increasingly used in recent years to achieve oral health. This study aimed to determine the antimicrobial effect of chamomile (Matrika), A. vera-green tea, and chlorhexidine (CHX) mouthwashes on some oral bacterial species.

Materials and Methods

This prospective experimental study investigated the antimicrobial properties of three mouthwashes, including chamomile (Matrika), A. vera -green tea, and CHX as well as distilled water as control on five bacterial species, including Streptococcus Oralis, Streptococcus sanguis, and Streptococcus mutans as primary colonizers and Porphyromonas gingivalis and Eikenella corrodens as secondary colonizers. Colony-forming unit was used to count the colonies and disc diffusion and well diffusion methods were used to measure the diameter of zone of inhibition. Data were analyzed by SPSS (version 22) software using descriptive statistics, ANOVA, Tukey, Kruskal-Wallis, and Mann-Whitney tests (α = 0.05).

Results

CHX had a significantly higher antibacterial effect than the other two mouthwashes in all three methods (P < 0.001). Further, the herbal mouthwashes in all three methods had a statistically significant effect on the bacterial species (P < 0.001). A. vera-green tea mouthwash had a significantly higher effect than chamomile mouthwash (Matrika) on all bacterial species except for S. sanguis (P < 0.05).

Conclusion

The findings showed that herbal mouthwashes had potentially antibacterial effects, but these effects were significantly lower than that of CHX. However, more clinical studies are needed to prove the current findings.

Phytochemical Composition and Antibacterial Activity of Barleria albostellata C.B. Clarke Leaf and Stem Extracts

Barleria albostellata (Acanthaceae) is a shrub located in South Africa and is relatively understudied. However, plants within this genus are well known for their medicinal and ethnopharmacological properties. This study aimed to characterise the phytochemical compounds and antibacterial efficacies of B. albostellata. Phytochemical analysis, fluorescence microscopy and gas chromatography-mass spectrometry (GC-MS) analysis were performed to determine the composition of compounds that may be of medicinal importance. Crude leaf and stem extracts (hexane, chloroform and methanol) were subjected to an antibacterial analysis against several pathogenic microorganisms. The qualitative phytochemical screening of leaf and stem extracts revealed the presence various compounds. Fluorescence microscopy qualitatively assessed the leaf and stem powdered material, which displayed various colours under bright and UV light. GC-MS chromatograms represents 10-108 peaks of various compounds detected in the leaf and stem crude extracts. Major pharmacologically active compounds found in the extracts were alpha-amyrin, flavone, phenol, phytol, phytol acetate, squalene and stigmasterol. Crude extracts positively inhibited Gram-positive and Gram-negative bacteria. Significance was established at p < 0.05 for all concentrations and treatments. These results indicate that the leaves and stems of B. albostellata are rich in bioactive compounds, which could be a potential source of antibacterial agents for treating various diseases linked to the pathogenic bacteria studied. Future discoveries from this plant could advance the use of indigenous traditional medicine and provide novel drug leads.

Natural Clerodendrum-derived tick repellent: learning from Nepali culture

Ticks attaching to ear canals of humans and animals are the cause of otoacariasis, common in rural areas of Nepal. The plant Clerodendrum viscosum is used in multiple indigenous systems of medicine by ethnic communities in the Indo-Nepali-Malaysian region. Visiting the Chitwan National Park, we learned that in indigenous medicine, flower extract of C. viscosum is utilized to treat digestive disorders and extracts from leaves as tick repellent to prevent ticks from invading or to remove them from the ear canal. The objective of our study was to provide support to indigenous medicine by characterizing the in vivo effect of leave extracts on ticks under laboratory conditions and its phytochemical composition. We collected plant parts of C. viscosum (leaves and flowers) and mango (Mangifera indica) leaves at the Chitwan National Park, previously associated with repellent activity to characterize their effect on Ixodes ricinus ticks by in vivo bioassays. A Q-ToF high-resolution analysis (HPLC-ESI-QToF) was conducted to elucidate phenolic compounds with potential repellent activity. Clerodendrum viscosum and M. indica leaf extracts had the highest tick repellent efficacy (%E = 80-100%) with significant differences when compared to C. viscosum flowers extracts (%E = 20-60%) and phosphate-buffered saline. Phytochemicals with tick repellent function as caffeic acid, fumaric acid and p-coumaric acid glucoside were identified in C. viscosum leaf extracts by HPLC-ESI-QToF, but not in non-repellent flower extracts. These results support the Nepali indigenous medicine application of C. viscosum leaf extracts to repel ticks. Additional research is needed for the development of natural and green repellent formulations to reduce the risks associated with ticks resistant to acaricides.

Evidence for Natural Products as Alternative Wound-Healing Therapies

Chronic, non-healing wounds represent a significant area of unmet medical need and are a growing problem for healthcare systems around the world. They affect the quality of life for patients and are an economic burden, being difficult and time consuming to treat. They are an escalating problem across the developed world due to the increasing incidence of diabetes and the higher prevalence of ageing populations. Effective treatment options are currently lacking, and in some cases chronic wounds can persist for years. Some traditional medicines are believed to contain bioactive small molecules that induce the healing of chronic wounds by reducing excessive inflammation, thereby allowing re-epithelisation to occur. Furthermore, many small molecules found in plants are known to have antibacterial properties and, although they lack the therapeutic selectivity of antibiotics, they are certainly capable of acting as topical antiseptics when applied to infected wounds. As these molecules act through mechanisms of action distinct from those of clinically used antibiotics, they are often active against antibiotic resistant bacteria. Although there are numerous studies highlighting the effects of naturally occurring small molecules in wound-healing assays in vitro, only evidence from well conducted clinical trials can allow these molecules or the remedies that contain them to progress to the clinic. With this in mind, we review wound-healing natural remedies that have entered clinical trials over a twenty-year period to the present. We examine the bioactive small molecules likely to be in involved and, where possible, their mechanisms of action.

Chemical Profile, Antioxidant and Antibacterial Activities, Mechanisms of Action of the Leaf Extract of Aloe arborescens Mill

Aloe arborescens Mill's extracts have been explored for antibacterial and antioxidant efficacies. However, there is limited information on its chemical composition and mechanism of action. The purpose of this study was to assess the chemical composition, antibacterial and antioxidant activities and mechanism of the whole leaf extract of A. arborescens Mill. The phytochemical profile was analysed with gas chromatography mass spectrometry (GC-MS). The antioxidant and antibacterial activities were screened using 1,1diphenyl2picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and micro-dilution assays, respectively. The effects of the extract on the bacterial respiratory chain dehydrogenase, membrane integrity and permeability were analysed using iodonitrotetrazolium chloride, 260 absorbing materials and relative electrical conductivity assays. GC-MS spectrum revealed 26 compounds with N,N'-trimethyleneurea (10.56%), xanthine (8.57%) and 4-hexyl-1-(7-ethoxycarbonylheptyl)bicyclo[4.4.0]deca-2,5,7-triene (7.10%), being the major components. The extract also exhibited antioxidant activity with median concentration (IC₅₀) values of 0.65 mg/mL on DPPH and 0.052 mg/mL on ABTS. The extract exhibited minimum inhibitory concentration (MIC) values ranging from 0.07 to 1.13 mg/mL. The extract inhibited the bacterial growth by destructing the activity of the respiratory chain dehydrogenase, membrane integrity and permeability. Therefore, the leaf extract has the potential to serve as a source of antibacterial and antioxidant compounds.

The Therapeutic Wound Healing Bioactivities of Various Medicinal Plants

The skin serves as the body's first line of defense, guarding against mechanical, chemical, and thermal damage to the interior organs. It includes a highly developed immune response that serves as a barrier against pathogenic infections. Wound healing is a dynamic process underpinned by numerous cellular activities, including homeostasis, inflammation, proliferation, and remodeling, that require proper harmonious integration to effectively repair the damaged tissue. Following cutaneous damage, microorganisms can quickly enter the tissues beneath the skin, which can result in chronic wounds and fatal infections. Natural phytomedicines that possess considerable pharmacological properties have been widely and effectively employed forwound treatment and infection prevention. Since ancient times, phytotherapy has been able to efficiently treat cutaneous wounds, reduce the onset of infections, and minimize the usage of antibiotics that cause critical antibiotic resistance. There are a remarkable number of wound-healing botanicals that have been widely used in the Northern Hemisphere, including Achiella millefolium, Aloe vera, Althaea officinalis, Calendula officinalis, Matricaria chamomilla, Curcuma longa, Eucalyptus, Jojoba, plantain, pine, green tea, pomegranate, and Inula. This review addresses the most often used medicinal plants from the Northern Hemisphere that facilitate the treatment of wounds, and also suggests viable natural alternatives that can be used in the field of wound care.

Phytochemical Profiles and Biological Studies of Selected Botanical Dietary Supplements Used in the United States

Based on their current wide bioavailability, botanical dietary supplements have become an important component of the United States healthcare system, although most of these products have limited scientific evidence for their use. The most recent American Botanical Council Market Report estimated for 2020 a 17.3% increase in sales of these products when compared to 2019, for a total sales volume of $11,261 billion. The use of botanical dietary supplements products in the United States is guided by the Dietary Supplement Health and Education Act (DSHEA) from 1994, enacted by the U.S. Congress with the aim of providing more information to consumers and to facilitate access to a larger number of botanical dietary supplements available on the market than previously. Botanical dietary supplements may be formulated for and use only using crude plant samples (e.g., plant parts such as the bark, leaves, or roots) that can be processed by grinding into a dried powder. Plant parts can also be extracted with hot water to form an "herbal tea." Other preparations of botanical dietary supplements include capsules, essential oils, gummies, powders, tablets, and tinctures. Overall, botanical dietary supplements contain bioactive secondary metabolites with diverse chemotypes that typically are found at low concentration levels. These bioactive constituents usually occur in combination with inactive molecules that may induce synergy and potentiation of the effects observed when botanical dietary supplements are taken in their different forms. Most of the botanical dietary supplements available on the U.S. market have been used previously as herbal remedies or as part of traditional medicine systems from around the world. Their prior use in these systems also provides a certain level of assurance in regard to lower toxicity levels. This chapter will focus on the importance and diversity of the chemical features of bioactive secondary metabolites found in botanical dietary supplements that are responsible for their applications. Many of the active principles of botanical dietary substances are phenolics and isoprenoids, but glycosides and some alkaloids are also present. Biological studies on the active constituents of selected botanical dietary supplements will be discussed. Thus, the present chapter should be of interest for both members of the natural products scientific community, who may be performing development studies of the products available, as well as for healthcare professionals who are directly involved in the analysis of botanical interactions and evaluation of the suitability of botanical dietary supplements for human consumption.

LC-MS Based Phytochemical Profiling towards the Identification of Antioxidant Markers in Some Endemic Aloe Species from Mascarene Islands

Aloe plant species have been used for centuries in traditional medicine and are reported to be an important source of natural products. However, despite the large number of species within the Aloe genus, only a few have been investigated chemotaxonomically. A Molecular Network approach was used to highlight the different chemical classes characterizing the leaves of five Aloe species: Aloe macra, Aloe vera, Aloe tormentorii, Aloe ferox, and Aloe purpurea. Aloe macra, A. tormentorii, and A. purpurea are endemic from the Mascarene Islands comprising Reunion, Mauritius, and Rodrigues. UHPLC-MS/MS analysis followed by a dereplication process allowed the characterization of 93 metabolites. The newly developed MolNotator algorithm was usedfor molecular networking and allowed a better exploration of the Aloe metabolome chemodiversity. The five species appeared rich in polyphenols (anthracene derivatives, flavonoids, phenolic acids). Therefore, the total phenolic content and antioxidant activity of the five species were evaluated, and a DPPH-On-Line-HPLC assay was used to determine the metabolites responsible for the radical scavenging activity. The use of computational tools allowed a better description of the comparative phytochemical profiling of five Aloe species, which showed differences in their metabolite composition, both qualitative and quantitative. Moreover, the molecular network approach combined with the On-Line-HPLC assay allowed the identification of 9 metabolites responsible for the antioxidant activity. Two of them, aloeresin A and coumaroylaloesin, could be the principal metabolites responsible for the activity. From 374 metabolites calculated by MolNator, 93 could be characterized. Therefore, the Aloe species can be a rich source of new chemical structures that need to be discovered.

Identification of natural products and FDA-approved drugs for targeting cancer stem cell (CSC) propagation

Here, we report the identification of key compounds that effectively inhibit the anchorage-independent growth and propagation of cancer stem cells (CSCs), as determined via screening using MCF7 cells, a human breast adenocarcinoma cell line. More specifically, we employed the mammosphere assay as an experimental format, which involves the generation of 3D spheroid cultures, using low-attachment plates. These positive hit compounds can be divided into 5 categories: 1) dietary supplements (quercetin and glucosamine); 2) FDA-approved drugs (carvedilol and ciprofloxacin); 3) natural products (aloe emodin, aloin, tannic acid, chlorophyllin copper salt, azelaic acid and adipic acid); 4) flavours (citral and limonene); and 5) vitamins (nicotinamide and nicotinic acid). In addition, for the compounds quercetin, glucosamine and carvedilol, we further assessed their metabolic action, using the Seahorse to conduct metabolic flux analysis. Our results indicate that these treatments can affect glycolytic flux and suppress oxidative mitochondrial metabolism (OXPHOS). Therefore, quercetin, glucosamine and carvedilol can reprogram the metabolic phenotype of breast cancer cells. Despite having diverse chemical structures, these compounds all interfere with mitochondrial metabolism. As these compounds halt CSCs propagation, ultimately, they may have therapeutic potential.

Focusing on the Role of Natural Products in Overcoming Cancer Drug Resistance: An Autophagy-Based Perspective

Autophagy is a critical cellular adaptive response in tumor formation. Nutritional deficiency and hypoxia exacerbate autophagic flux in established malignancies, promoting tumor cell proliferation, migration, metastasis, and resistance to therapeutic interventions. Pro-survival autophagy inhibition may be a promising treatment option for advanced cancer. Furthermore, excessive or persistent autophagy is cytotoxic, resulting in tumor cell death. Targeted autophagy activation has also shown significant promise in the fight against tumor drug resistance. Several research groups have examined the ability of natural products (NPs) such as alkaloids, terpenoids, polyphenols, and anthraquinones to serve as autophagy inhibitors or activators. The data support the capacity of NPs that promote lethal autophagy or inhibit pro-survival autophagy from being employed against tumor drug resistance. This paper discusses the potential applications of NPs that regulate autophagy in the fight against tumor drug resistance, some limitations of the current studies, and future research needs and priorities.

Natural Compounds Such as Hericium erinaceus and Coriolus versicolor Modulate Neuroinflammation, Oxidative Stress and Lipoxin A4 Expression in Rotenone-Induced Parkinson's Disease in Mice

BACKGROUND

A growing body of research suggests that oxidative stress and neuroinflammation are early pathogenic features of neurodegenerative disorders. In recent years, the vitagene system has emerged as a potential target, as it has been shown to have a high neuroprotective power. Therefore, the discovery of molecules capable of activating this system may represent a new therapeutic target to limit the deleterious consequences induced by oxidative stress and neuroinflammation, such as neurodegeneration. Lipoxins are derived from arachidonic acid, and their role in the resolution of systemic inflammation is well established; however, they have become increasingly involved in the regulation of neuroinflammatory and neurodegenerative processes. Our study aimed at activating the NF-E2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) redox system and increasing lipoxin A4 for the modulation of antioxidant stress and neuroinflammation through the action of two fungi in a rotenone-induced Parkinson's model.

METHODS

During the experiment, mice received Hericium erinaceus, Coriolus versicolor or a combination of the two (200 mg/kg, orally) concomitantly with rotenone (5 mg/kg, orally) for 28 days.

RESULTS

The results obtained highlighted the ability of these two fungi and, in particular, their ability through their association to act on neuroinflammation through the nuclear factor-kB pathway and on oxidative stress through the Nrf2 pathway. This prevented dopaminergic neurons from undergoing apoptosis and prevented the alteration of typical Parkinson's disease (PD) markers and α-synuclein accumulation. The action of Hericium erinaceus and Coriolus versicolor was also able to limit the motor and non-motor alterations characteristic of PD.

CONCLUSIONS

Since these two mushrooms are subject to fewer regulations than traditional drugs, they could represent a promising nutraceutical choice for preventing PD.

Isolation of Aloe saponaria-Derived Extracellular Vesicles and Investigation of Their Potential for Chronic Wound Healing

A chronic wound is caused by a failure to progress through the normal phases of wound repair in an orderly and timely manner. To induce skin regeneration while inhibiting chronic inflammation, numerous natural products, and in particular, plant-derived biomaterials, have been developed. Aloe saponaria, is known to contain flavonoid and phenolic acid compounds with anti-oxidative and anti-inflammatory properties. Here, we isolated extracellular vesicles (EVs) from Aloe saponaria by polyethylene glycol (PEG)-based precipitation and investigated their potential as a therapeutic for chronic wound healing. The Aloe saponaria-derived EVs (AS-EVs) showed no significant cytotoxicity on several cell types, despite a high level of intracellular uptake. When lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were treated with AS-EVs, significant reductions in the expression of pro-inflammatory genes, such as interleukin-6 and interleukin-1β, were observed. Proliferation and migration of human dermal fibroblasts, as determined by the water-soluble tetrazolium salt-8 and transwell migration assay, respectively, were shown to be promoted by treatment with AS-EVs. It was also demonstrated that AS-EVs enhanced tube formation in human umbilical vein endothelial cells, indicating a stimulatory activity on angiogenesis; one of the crucial steps for effective wound healing. Collectively, our results suggest the potential of AS-EVs as a natural therapeutic for chronic wound healing.

Phytochemistry and Biological Activity of Medicinal Plants in Wound Healing: An Overview of Current Research

Wound healing is a complicated process, and the effective management of wounds is a major challenge. Natural herbal remedies have now become fundamental for the management of skin disorders and the treatment of skin infections due to the side effects of modern medicine and lower price for herbal products. The aim of the present study is to summarize the most recent in vitro, in vivo, and clinical studies on major herbal preparations, their phytochemical constituents, and new formulations for wound management. Research reveals that several herbal medicaments have marked activity in the management of wounds and that this activity is ascribed to flavonoids, alkaloids, saponins, and phenolic compounds. These phytochemicals can act at different stages of the process by means of various mechanisms, including anti-inflammatory, antimicrobial, antioxidant, collagen synthesis stimulating, cell proliferation, and angiogenic effects. The application of natural compounds using nanotechnology systems may provide significant improvement in the efficacy of wound treatments. Increasing the clinical use of these therapies would require safety assessment in clinical trials.

Valorization of Aloe vera Skin By-Products to Obtain Bioactive Compounds by Microwave-Assisted Extraction: Antioxidant Activity and Chemical Composition

Aloe vera skin (AVS) is a major by-product of Aloe processing plants all over the world. In this study, response surface methodology was used to optimize microwave-assisted extraction (MAE) of bioactive compounds from AVS. The influence of extraction parameters, such as ethanol concentration (%Et), extraction temperature (T), time (t) and solvent volume (V), on extraction yield (Y), total phenolic content (TPC), antioxidant activity (DPPH and FRAP methods) and aloin content, was studied. Optimum extraction conditions were determined as 80% ethanol, 80 °C, 36.6 min and 50 mL and optimized extracts showed interesting contents of polyphenols and antioxidant performance. The phenolic profile was determined by HPLC-DAD/MS and some major phenolic compounds, such as aloin A, aloin B, aloesin, aloe-emodin, aloeresin D, orientin, cinnamic acid and chlorogenic acid, were quantified while eight other compounds were tentatively identified. Moreover, structural and thermal properties were studied by FTIR and TGA analyses, respectively. The obtained results suggested the potential of AVS as a promising source of bioactive compounds, thus increasing the added value of this agricultural waste.

Phytotherapeutic Approaches to the Prevention of Age-Related Changes and the Extension of Active Longevity

Maintaining quality of life with an increase in life expectancy is considered one of the global problems of our time. This review explores the possibility of using natural plant compounds with antioxidant, anti-inflammatory, anti-glycation, and anti-neurodegenerative properties to slow down the onset of age-related changes. Age-related changes such as a decrease in mental abilities, the development of inflammatory processes, and increased risk of developing type 2 diabetes have a significant impact on maintaining quality of life. Herbal preparations can play an essential role in preventing and treating neurodegenerative diseases that accompany age-related changes, including Alzheimer’s and Parkinson’s diseases. Medicinal plants have known sedative, muscle relaxant, neuroprotective, nootropic, and antiparkinsonian properties. The secondary metabolites, mainly polyphenolic compounds, are valuable substances for the development of new anti-inflammatory and hypoglycemic agents. Understanding how mixtures of plants and their biologically active substances work together to achieve a specific biological effect can help develop targeted drugs to prevent diseases associated with aging and age-related changes. Understanding the mechanisms of the biological activity of plant complexes and mixtures determines the prospects for using metabolomic and biochemical methods to prolong active longevity.

Up-to-Date Overview of the Use of Natural Ingredients in Sunscreens

The photoprotective skincare segment is in high demand to meet consumer concerns on UV-induced skin damage, with a recent trend towards sunscreen alternatives with a natural origin. In this study, the use of natural ingredients, either from terrestrial or marine origin, in a panel of 444 sunscreen commercial formulations (2021) was analyzed. Ingredients from terrestrial organisms represent the large majority found in the analyzed sunscreen formulations (48%), whereas marine ingredients are present only in 13% of the analyzed products. A deeper analysis regarding the most prevalent families of ingredients from terrestrial and marine organisms used as top ingredients is also presented, as well as their mechanisms of action. This study provides an up-to-date overview of the sunscreen market regarding the use of natural ingredients, which is of relevance for scientists involved in the development of new sunscreens to identify opportunities for innovation.

Aloe vera and Streptozotocin-Induced Diabetes Mellitus

Diabetes mellitus is defined as prolonged hyperglycemia, which can harm the eyes, kidneys, and cardiovascular and neurological systems. Herbal agents and their derived supplements have been used for treatment of diabetes mellitus as a part of integrated complementary medicine for centuries. Numerous studies have considered Aloe vera (L.) Burm.f, Xanthorrhoeaceae, as an alternative medicine due to its abundant bioactive chemicals, such as alkaloids, anthraquinones, and enthrones, with therapeutical properties including antioxidant, anti-inflammatory, neuro-protective, and anti-diabetic effects. Aloe vera has received considerable attention in traditional medicine for the treatment of several diseases including diabetes mellitus. Numerous studies have investigated the effects of herbal agents on diabetes mellitus using a streptozotocin-induced diabetic model. Thereby, this article reviews the effects of Aloe vera prescription on streptozotocin-induced diabetes mellitus to provide a clear insight into the role of this medicinal plant in several biological functions, such as antioxidant, wound healing, anti-inflammatory, anti-hyperglycemic, and anti-hyperlipidemic in diabetic models.

Development of an LC-DAD-MS-Based Method for the Analysis of Hydroxyanthracene Derivatives in Food Supplements and Plant Materials

Products based on plants containing hydroxyanthracene derivatives (HADs)—such as Rheum, Cassia, and Aloe species—are widely used in food supplements or nutraceuticals due to their laxative effects. A more restricted control of HAD contents in food supplements has been implemented by EU Regulation 2021/468, in order to increase the safety of these preparations. Due to their toxicity, aloin A, aloin B, aloe emodin, emodin, and the synthetic derivative danthron have been listed as prohibited substances in food supplements, being tolerated in amounts < 1 mg kg−1 in marketed products. In this work, we report the development of a sensitive and fast LC−DAD−MS-based procedure for the determination of these five compounds in food supplements and plant materials or extracts. The entire procedure includes a simple sample preparation step, where target analytes are concentrated by means of solvent extraction and evaporative concentration (solid samples), or by lyophilisation (liquid samples). The average LOQ of 0.10 mg/L, LOD of 0.03 mg/L, accuracy, and precision with CVs below 12.72 were obtained for the studied analytes. This method is suitable for assessing the compliance of commercial products and raw materials with EU Regulation 2021/468. Furthermore, the proposed method can represent a starting point for the development of a unique and standardised analytical approach for the determination of other HADs under the attention of EU authorities.

Comparative Evaluation of the Effect of Aloe Vera Gel, Olive Oil, and Compound Aloe Vera Gel-Olive Oil on Prevention of Pressure Ulcer: A Randomized Controlled Trial

Background

One of the most common problems in the intensive care units (ICUs) is pressure ulcers (PUs). The present study aimed to evaluate the effectiveness of aloe vera gel, olive oil, and compound aloe vera gel-olive oil in the prevention of PUs.

Materials and Methods

This randomized clinical trial was conducted on 240 patients. They were randomly divided into four groups, aloe vera gel (n = 60), olive oil (n = 60), aloe vera gel-olive oil combination (n = 60), and control (n = 60). Braden scale and National Pressure Ulcer Advisory Panel scale were used to collect data. The intervention was performed for 30 days. In the intervention and control groups, the patient received routine care. In each intervention group, 10-15 ml of olive oil or aloe vera gel or a combination of olive oil and aloe vera was rubbed into body areas under pressure.

Results

There were no PUs detected in all groups before the intervention; after the intervention, 12 patients in the olive group, 20 patients in the aloe vera group, 10 patients in the aloe vera-olive combination group, and 22 patients in the control group developed PUs. The results reported 40% of the patients with stage 1 PU and 10% of them with stage 2.

Conclusion

Due to the effectiveness of olive oil and aloe vera-olive oil combination in preventing PU, it is recommended to use these herbal compounds in preventing PU on ICU patients.

Medicinal Plants for Prophylaxis and Therapy of Common Infectious Diseases In Poultry-A Systematic Review of In Vivo Studies

Medicinal plants for prophylaxis and therapy of common infectious diseases in poultry have been studied for several years. The goal of this review was to systematically identify plant species and evaluate their potential in prophylaxis and therapy of common diseases in poultry caused by bacteria and gastrointestinal protozoa. The procedure followed the recommendations of the PRISMA statement and the AMSTAR measurement tool. The PICOS scheme was used to design the research questions. Two databases were consulted, and publications were manually selected, according to predefined in- and exclusion criteria. A scoring system was established to evaluate the remaining publications. Initially, 4197 identified publications were found, and 77 publications remained after manual sorting, including 38 publications with 70 experiments on bacterial infections and 39 publications with 78 experiments on gastrointestinal protozoa. In total, 83 plant species from 42 families were identified. Asteraceae and Lamiaceae were the most frequently found families with Artemisia annua being the most frequently found plant, followed by Origanum vulgare. As compared to placebo and positive or negative control groups, antimicrobial effects were found in 46 experiments, prebiotic effects in 19 experiments, and antiprotozoal effects in 47 experiments. In summary, a total of 274 positive effects predominated over 241 zero effects and 37 negative effects. Data indicate that O. vulgare, Coriandrum sativum, A. annua, and Bidens pilosa are promising plant species for prophylaxis and therapy of bacterial and protozoal diseases in poultry.

Advanced drug delivery systems containing herbal components for wound healing

Management of chronic wound has an immense impact on social and economic conditions in the world. Healthcare costs, aging population, physical trauma, and comorbidities of diabetes and obesity seem to be the major factors of this increasing incidence of chronic wounds. Conditions of chronic wound could not restore functional epidermis; thus, delaying the closure of the wound opening in an expected manner. Failures in restoration of skin integrity delay healing due to changes in skin pathology, such as chronic ulceration or nonhealing. The role of different traditional medicines has been explored for use in the healing of cutaneous wounds, where several phytochemicals, such as flavonoids, alkaloids, phenolic acids, tannins are known to provide potential wound healing properties. However, the delivery of plant-based therapeutics could be improved by the novel platform of nanotechnology. Thus, the objectives of novel delivery strategies of principal bioactive from plant sources are to accelerate the wound healing process, avoid wound complications and enhance patient compliance. Therefore, the opportunities of nanotechnology-based drug delivery of natural wound healing therapeutics have been included in the present discussion with special emphasis on nanofibers, vesicular structures, nanoparticles, nanoemulsion, and nanogels.

Medicinal plants cultivated in urban home gardens in Heredia, Costa Rica

BACKGROUND

Urban ethnobotanical research in Costa Rica is rather rare and home gardens are poorly studied so far. Investigating their biodiversity is crucial in gathering knowledge on the uses of this particular flora, especially related to the owners' health. This study therefore explores the diversity and knowledge of medicinal plants of private garden owners from three different urban neighborhoods in Heredia, Costa Rica, an thus far understudied area.

METHODS

Semi-structured interviews (n = 61) were conducted with garden owners in three socioeconomically different urban neighborhoods (Central Heredia, Maria Auxiliadora and Bernardo Benavides). Information was collected about medicinal plants cultivated in the garden, treatments, plant part used and mode of administration. All species were identified and their geographical origin was determined. This information was then compared with the available regional and local (ethno)pharmacopoeias to detect possible newly documented uses.

RESULTS

The majority or 90% of garden owners who also held knowledge on medicinal plants species were women (n = 30) of all ages (between 26 and 85 years old). A list of 27 species of medicinal plants was obtained from the participants of three urban neighborhoods. In Central Heredia, 74% (n = 20) of the total species were present, in Maria Auxiliadora 33% (n = 9) and in Bernardo Benavides 56% (n = 15). Most plant species were used by the participants to treat respiratory problems (11 spp.), hair and skin problems (9 spp.) and digestive disorders (8 spp.). Some plants were used to treat multiple ailments (10 spp.). About a third of all species (n = 8) were used by the participants to treat disorders that were not indicated in the regional and local pharmacopoeias. More specifically, Aloe saponaria, Blechum pyramidatum, Costus scaber, Impatiens walleriana, Lippia alba, Tradescantia zebrina, Psidium friedrichsthalianum and Solenostemon scutellarioides used for medicinal purposes by the participants were not found in the above-mentioned resources.

CONCLUSIONS

The present study provides new information about the use of medicinal plants in a thus far understudied urban area in Costa Rica. We documented new medicinal uses for several plants listed in the regional and local pharmacopoeias as well as for plants not previously reported in an urban environment. In general, there is little information about the types of plants used for medicinal purposes in urban ecosystems in Costa Rica. Although the country has a high endemic diversity of plants, many exotic medicinal plant species were introduced by the Spaniards during the colonization and by Afro-Costa Rican descendants. The present results thus show how the diversity of the medicinal plants used by these garden owners' confirms a socioeconomic gradient and reflects both Costa Rica's colonial history as well as the current epidemiological profile of the country. These findings underline the need for more ethnobotanical research in urban areas in Costa Rica.

Aloin Regulates Matrix Metabolism and Apoptosis in Human Nucleus Pulposus Cells via the TAK1/NF-κB/NLRP3 Signaling Pathway

Intervertebral disc degeneration (IDD) is a degenerative disease that is characterized by decreased matrix synthesis and extra degradation, nucleus pulposus cells (NPCs) apoptosis, and infiltration of inflammatory factors. Aloin, a colored compound from aloe plants, has been shown to be effective against skeletal degenerative diseases, but it is unclear whether it is protective against IDD. Herein, we investigated the role of aloin in NPCs. In our study, the upregulation of proinflammatory factors, apoptosis, and unbalanced matrix metabolism were observed in degenerative NP tissues. We found that aloin had a curative effect on extracellular matrix metabolism and apoptosis in TNF-alpha- (TNF-α-) treated NPCs by inhibiting oxidative stress and the proinflammatory factor expression. Further investigation revealed that aloin treatment suppressed the TAK1/NF-κB pathway. Moreover, the expression level of the NLPR3 inflammasome was downregulated after aloin treatment in TNF-α-treated NPCs. In summary, our results demonstrated that aloin treatment can reverse TNF-α-induced unbalanced matrix metabolism and apoptosis of NPCs via the TAK1/NF-κB/NLRP3 axis. This study supports that aloin can be a promising therapeutic agent for IDD.

Antidiabetic Medicinal Plants Used in Democratic Republic of Congo: A Critical Review of Ethnopharmacology and Bioactivity Data

Several studies have been conducted and published on medicinal plants used to manage Diabetes Mellitus worldwide. It is of great interest to review available studies from a country or a region to resort to similarities/discrepancies and data quality. Here, we examined data related to ethnopharmacology and bioactivity of antidiabetic plants used in the Democratic Republic of Congo. Data were extracted from Google Scholar, Medline/PubMed, Scopus, ScienceDirect, the Wiley Online Library, Web of Science, and other documents focusing on ethnopharmacology, pharmacology, and phytochemistry antidiabetic plants used in the Democratic Republic of Congo from 2005 to September 2021. The Kew Botanic Royal Garden and Plants of the World Online web databases were consulted to verify the taxonomic information. CAMARADES checklist was used to assess the quality of animal studies and Jadad scores for clinical trials. In total, 213 plant species belonging to 72 botanical families were reported. Only one plant, Droogmansia munamensis, is typically native to the DRC flora; 117 species are growing in the DRC and neighboring countries; 31 species are either introduced from other regions, and 64 are not specified. Alongside the treatment of Diabetes, about 78.13% of plants have multiple therapeutic uses, depending on the study sites. Experimental studies explored the antidiabetic activity of 133 plants, mainly in mice, rats, guinea pigs, and rabbits. Several chemical classes of antidiabetic compounds isolated from 67 plant species have been documented. Rare phase II clinical trials have been conducted. Critical issues included poor quality methodological protocols, author name incorrectly written (16.16%) or absent (14.25%) or confused with a synonym (4.69%), family name revised (17.26%) or missing (1.10%), voucher number not available 336(92.05%), ecological information not reported (49.59%). Most plant species have been identified and authenticated (89.32%). Hundreds of plants are used to treat Diabetes by traditional healers in DRC. However, most plants are not exclusively native to the local flora and have multiple therapeutic uses. The analysis showed the scarcity or absence of high-quality, in-depth pharmacological studies. There is a need to conduct further studies of locally specific species to fill the gap before their introduction into the national pharmacopeia.

Anthraquinones from Aloe spp. inhibit Cryptococcus neoformans sensu stricto: effects against growing and mature biofilms

This study aimed to evaluate the in vitro effect of aloe emodin, barbaloin and chrysophanol on growing and mature biofilms of Cryptococcus neoformans sensu stricto. The compounds were added at the moment of inducing biofilm growth or after growth for 72 h to evaluate their effects on growing and mature biofilms, respectively. Then, biofilm biomass was evaluated by crystal violet staining and metabolic activity by the XTT reduction assay. Morphological alterations were also evaluated by laser scanning confocal microscopy. Aloe emodin and barbaloin affected growing biofilms and disrupted mature biofilms, reducing metabolic activity by > 60% and biomass by > 70%. Chrysophanol only inhibited mature biofilms, but to a lesser extent. In conclusion, anthraquinones, especially aloe emodin and barbaloin, show a relevant effect against growing and mature biofilms of C. neoformans sensu stricto.

Review on the phytochemistry and toxicological profiles of Aloe vera and Aloe ferox

Background

Aloe vera and Aloe ferox have over the years been among the most sought-after Aloe species in the treatment of ailments worldwide. This review provides categorized literature on the phytochemical and scientifically proven toxicological profiles of A. vera and A. ferox to facilitate their exploitation in therapy.

Main body of the abstract

Original full-text research articles were searched in PubMed, ScienceDirect, Research gate, Google Scholar, and Wiley Online Library using specific phrases. Phenolic acids, flavonoids, tannins, and anthraquinones were the main phytochemical classes present in all the two Aloe species. Most of the phytochemical investigations and toxicity studies have been done on the leaves. Aloe vera and Aloe ferox contain unique phytoconstituents including anthraquinones, flavonoids, tannins, sterols, alkaloids, and volatile oils. Aloe vera hydroalcoholic leaf extract showed a toxic effect on Kabir chicks at the highest doses. The methanolic, aqueous, and supercritical carbon dioxide extracts of A. vera leaf gel were associated with no toxic effects. The aqueous leaf extract of A. ferox is well tolerated for short-term management of ailments but long-term administration may be associated with organ toxicity. Long-term administration of the preparations from A. vera leaves and roots was associated with toxic effects.

Short conclusion

This review provides beneficial information about the phytochemistry and toxicity of A. vera and A. ferox and their potential in the treatment of COVID-19 which up to date has no definite cure. Clinical trials need to be carried out to clearly understand the toxic effects of these species.

A study of rural chicken farmers, diseases and remedies in the Eastern Cape province of South Africa

The source of emerging diseases and antimicrobial resistance is of increasing interest to epidemiologists. This paper looks at village chickens as such a source. In addition, infectious diseases constitute a major challenge to the growth and profitability of the rural poultry sector in Sub-Saharan Africa. A serological survey was conducted to estimate the apparent seroprevalence of selected chicken diseases in the Eastern Cape Province of South Africa alongside a sociological survey of poultry farmers and the remedies most commonly used to prevent diseases in their flocks. Sera collected from village chickens (n = 1007) in the province were screened for specific antibodies against Newcastle disease (ND), avian influenza (AI), avian infectious bronchitis (IB) and Mycoplasma gallisepticum (MG). The overall seroprevalence of ND, AI, IB and MG in the province was found to be 69.2 % (95 % CI 51.9-86.5%); 1.8 % (95 % CI 0.2-3.4%); 78.5 % (95 % CI 74.9-82%) and 55.8 % (95 % CI 41.3-70.3%) respectively with clustering found at the District level. Cross hemagglutination inhibition (HI) tests indicated that the chickens were exposed to the ND vaccine. AI ELISA-positive samples were tested using HIs against the H5, H6 and H7-subtypes, but only H6-specific antibodies were detected. Avian influenza strains shared the common ancestor responsible for the 2002 chicken outbreak in KwaZulu-Natal Province. The majority of chicken farmers were females and pensioners (69 % and 66.1 % respectively) and had a primary school education (47.1 %). Traditional remedies were commonly used by farmers (47.15 %) and among the remedies, Aloe plant (Aloe ferox Mill.) or ikhala (Xhosa) was the most commonly used product (28.23 %) for preventing and reducing mortalities among village chickens. The findings stress the importance of village chickens as a substitute for social welfare and highlight the exposure of village chickens to important chicken pathogens. The economic impact of these pathogens on the development of this sub-sector needs further investigation. Village chickens are a potential source of virulent Newcastle disease virus (NDV) because of the lack of vaccination and biosecurity. They may serve as amplification hosts which increases the probability that virulent NDV could spill over into commercial poultry flocks due to large amounts of circulating virus. The zoonotic threat of circulating H6N2 viruses raise concern due to their mutation and reassortment among chickens and a potential movement of infected birds within the province. Finally, the use of antibiotics by untrained chicken farmers constitute another major concern as it could serve as a source of antimicrobial resistance (AMR).

Evaluation of the Antimalarial Activity of the Leaf Latex of Aloe weloensis (Aloaceae) against Plasmodium Parasites

Background

The lack of available vaccines and the emerging resistance to antimalarial drugs have provided the necessity to find noble antimalarial plant-based medicines. The leaf latex Aloe weloensis has been used in folk medicine against malarial and other human ailments in Ethiopia. Hence, the present study aimed to investigate the antimalarial activity of the leaf latex of A. weloensis against Plasmodium parasites.

Materials and Methods

The prophylactic and curative models were employed to determine the in vivo antimalarial activity of the leaf latex A. weloensis against P. berghei infected mice, and the antioxidant activity of the latex was assessed using diphenyl-1-picrylhydrazine (DPPH) assay. Female mice were recruited for toxicity study, and the leaf latex was administered to fasted mice at a dose of 5000 mg/kg. The mice were kept under continuous observation for fourteen days for any signs of overt toxicity.

Results

The leaf latex of A. weloensis was safe up to 5000 mg/kg, and the latex endowed free radical inhibition activity (IC₅₀ = 10.25 μg/ml). The latex of A. weloensis leaf demonstrated the inhibitory activity against the 3D7 strain of P. falciparum (IC₅₀ = 9.14 μg/ml). The prophylactic and curative effect of the latex was found to be dose-dependent. The mice's parasitemia level was significantly (p < 0.001) reduced at all tested doses of the leaf latex compared to negative control in the curative test. Parasitemia reduction was significant (200 mg/kg, p < 0.01, and 400 and 600 mg/kg, p < 0.001) in the prophylactic test compared to the control. In addition, the leaf latex significantly (p < 0.01) improved mean survival time, packed cell volume, rectal temperature, and bodyweight of P. berghei infected mice.

Conclusion

The leaf latex of Aloe weloensis was endowed with the antimalarial activity at various doses, corroborating the plant's claimed traditional use.

Phytochemical and In-Vivo Anti-Arthritic Significance of Aloe thraskii Baker in Combined Therapy with Methotrexate in Adjuvant-Induced Arthritis in Rats

Unlike other widely known Aloe species used for treatment of rheumatoid arthritis, this species suffers from a lack of sufficient studies on its biological and chemical characters. This is what drove us to perform this work to evaluate the in vivo anti-arthritic potential of its leaf ethanolic extract. The in vivo anti-arthritic activity of the leaf ethanolic extract at 100 and 200 mg/kg/day b.wt. was evaluated alone and in combination with methotrexate (MTX) using complete Freund's adjuvant. Serum levels of rheumatoid factor, anti-cyclic citrullinated peptide (anti-CCP), cytokines pro-inflammatory marker, inflammatory mediator serum levels, and oxidative stress mediators were analyzed, in addition to liver function. Orientin, isoorientin, β-sitosterol, its palmitate and its glucoside were isolated. The combined therapy of MTX and the leaf ethanolic extract (especially at 200 mg/kg b.wt.) group showed better activity compared to MTX alone. Moreover, the combined therapy provided additional benefits in lowering the liver toxicity by comparison to MTX alone. We concluded that a synergetic combination of the leaf ethanolic extract and MTX is beneficial in the management of rheumatoid arthritis with fewer side effects on liver function, as well as the possibility of the leaf extract to stand alone as an effective natural anti-arthritic agent.

Molecular mechanisms and associated cell signalling pathways underlying the anticancer properties of phytochemical compounds from Aloe species (Review)

Naturally occurring components from various species of Aloe have been used as traditional folk medicine since the ancient times. Over the last few decades, the therapeutic effects of extracts and phytochemical compounds obtained from Aloe vera have been proven in preclinical and clinical studies. Recently, compounds from other Aloe species apart from Aloe vera have been investigated for the treatment of different diseases, with a particular focus on cancer. In the present review, the effects of phytochemical compounds obtained from different Aloe species are discussed, with a specific focus on the effects on cell signalling in cancer and normal cells, and their selectivity and efficacy. This information will be useful for the application of Aloe-derived compounds as therapeutic agents, either alone or in combination with other standard drugs for cancer treatment.

Analysis of the Composition of Lyophilisates Obtained from Aloe arborescens Gel of Leaves of Different Ages from Controlled Crops

The aim of the study is to evaluate the composition of lyophilisates obtained from Aloe arborescens leaf gel at the age of one to four years. The leaves were obtained from controlled crops, which allowed to exclude environmental factors as variables. It was confirmed that the lyophilisates obtained from different years of Aloe arborescens leaf gel varied in chromatographic analyses in terms of aloin A and aloenin A content (high-performance liquid chromatography with diode-array detection HPLC-DAD, high-performance liquid chromatography with tandem mass spectrometric detection HPLC-MS/MS). Similarly, while testing the phenolic acids and the sum of polyphenols content, differences in their levels in leaf gel lyophilisates from plants of individual years were observed (spectrophotometric method UV-VIS). The lyophilisate composition analysis showed that the one-year-old leaves were characterized by the highest content of aloin A and aloenin A. While the content of polyphenols, including phenolic acids, was higher in the leaves of older plants. The antioxidant potential of the tested lyophilisates was assessed simultaneously. Regardless of the research model used (CUPRAC, DPPH, ABTS), an antioxidant effect was noted for Aloe arborescens leaves.

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.

Ethnopharmacology, Phytochemistry and Biological Activities of Native Chilean Plants

The native flora of Chile has unique characteristics due to the geographical situation of the country, with the vast desert in the North, Patagonia in the South, the Andean Mountains on the east and the Pacific Ocean on the west. This exclusivity is reflected in high concentrations of phytochemicals in the fruits and leaves of its native plants. Some examples are Aristotelia chilensis (Molina), Stuntz (maqui), Berberis microphylla G. Forst. (calafate), Peumus boldus Molina (boldo), Ribes magellanicum Poir. (Magellan currant), Ugni molinae Turcz. (murtilla), Rubus geoides Sm. (miñe miñe), Drimys winteri J.R.Forst. & G.Forst. (canelo), Luma apiculata (DC.) Burret (arrayán) distributed throughout the entire Chilean territory. Some of these Chilean plants have been used for centuries in the country's traditional medicine. The most recent studies of phytochemical characterization of parts of Chilean plants show a wide spectrum of antioxidant compounds, phenolic components, terpenoids and alkaloids, which have shown biological activity in both in vitro and in vivo studies. This manuscript covers the entire Chilean territory characterizing the phytochemical profile and reporting some of its biological properties, focusing mainly on antioxidant, anti-inflammatory, antimicrobial, chemopreventive and cytotoxic activity, and potential against diabetes, metabolic syndrome and gastrointestinal disorders.

Graphene oxide exhibited positive effects on the growth of Aloe vera L

There is increasing evidence for graphene associated plant growth promotion, however, the chronic effects of soil-applied graphene remain largely unexplored. The present study investigated the morphological, physiological and biochemical responses of graphene oxide (GO) on Aloe vera L. over the concentration range of 0-100 mg/L for four months. Our results demonstrated that GO, with the best efficiency at 50 mg/L, could enhance the photosynthetic capacity of leaves, increase the yield and morphological characters of root and leaf, improve the nutrient (protein and amino acid) contents of leaf, without reducing the content of the main bioactive compound aloin. Compared with leaves, the effect of GO on root growth was more obvious. Although the electrolyte leakage and MDA content were raised at high concentrations, GO treatment did not increase the root antioxidant enzymes activity or decrease the root vigor, which excluding typical stress response. Furthermore, injection experiments showed that the GO in vivo did not change the plant growth state obviously. Taken together, our study revealed the role of GO in promoting Aloe vera growth by stimulating root growth and photosynthesis, which would provide theory basis for GO application in agriculture and forestry.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12298-021-00979-3.

Safety evaluation of Aloe vera soft capsule in acute, subacute toxicity and genotoxicity study

Aloe vera has been widely used in health and nutritional supplements in Chinese herbal medicine. Furthermore, Aloe vera production has been an emerging industry for making cosmetics and functional food. However, the reported adverse effects raised questions as to whether Aloe vera and its products were safe enough to be used in medicine and health care. In view of this, the safety evaluation of Aloe vera products before marketing is very important. The present study aimed to assess the toxicological profile of Aloe vera soft capsule (ASC), through acute, subacute toxicity and genotoxicity tests. Male and female ICR mice were received by oral gavage 15000 mg/kg bodyweight of ASC in the acute toxicity test. Male and female SD rats were fed on diet blended with different doses of ASC (equivalent to 832.5, 1665 and 3330 mg/kg bodyweight of ASC) for the subacute toxicity test. In the acute toxicity study, no mortality or behavioral changes were observed, indicating the LD₅₀ was higher than 15000 mg/kg bodyweight. In the subacute toxicity test, no significant changes were observed in bodyweight, food consumption, hematological, biochemical or histopathological parameters in the rats exposed. These data suggested that ASC used in this study did not produce any marked subacute toxic effects up to a maximum concentration of 3330 mg/kg bodyweight. In the genotoxicity study, ASC showed no mutagenic activity in the Ames test and no evidence of potential to induce bone marrow micronucleus or testicular chromosome aberrations in ICR mice exposed to 10000 mg/kg bodyweight. Collectively, ASC could be considered safe before it was marketed as a laxative and moistening health food.