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The aim of this study was to isolate antimicrobial compounds from the roots of Aloe kefaensis, a plant endemic to Ethiopia and used to treat various microbial infections by traditional healers. The air-dried and powdered plant material was sequentially extracted with petroleum ether, dichloromethane, acetone, and methanol. Then, each solvent extract was evaluated for its in vitro antimicrobial activity against four bacterial (Escherichia coli, Bacillus cereus, Salmonella typhimurium, and Staphylococcus aureus) and one fungal (Candida albicans) strains using the agar disk diffusion method. Superior antimicrobial activity was exhibited against all the strains by dichloromethane extract, with the highest activity observed against S. typhi (inhibition zone diameter of 23.0 mm at 200 mg/mL). Due to similarity in their TLC profile, the acetone and dichloromethane extracts were combined and subjected to silica gel column chromatography for fractionation and isolation of the compounds. Separation of these extracts using silica gel column chromatography resulted in four anthraquinones: deoxyerythrolaccin (1), chrysophanol (2), laccaic acid D-methyl ester (3), and 3, 8-dihydroxy-1-methylanthraquinone-2-carboxylic acid (4) and one preanthraquinone, aloesaponol II (5). The structure of these compounds was established using NMR (1D and 2D) spectroscopic analysis and comparison with reported literature data. The isolated compounds were evaluated for antimicrobial activity and showed varying degrees of potency. Compounds 2 and 4 showed the highest activity against Salmonella typhimurium at 10 mg/mL, with a zone of inhibition of 28.5 and 25.0 mm, respectively, in comparison to gentamicin (26.0 mm inhibition zone diameter at 10 mg/mL). Therefore, this strong antimicrobial activity of the extracts and isolates supports the traditional usage of Aloe kefaensis to treat microbial diseases.

Fungal infections are responsible for about 70–80% of the losses in agricultural production brought on by microbial diseases. Synthetic fungicides have been employed to manage plant diseases caused by phytopathogenic fungi but their use has been criticized due to unfavorable side effects. As alternative strategies, botanical fungicides have caught the interest of many researchers in recent years. There are numerous experimental studies on the fungicidal activities of phytochemicals against phytopathogenic fungi, but there is not a thorough review article that summarizes these experimental studies. The purpose of this review is therefore to consolidate data from in vitro and in vivo studies on the antifungal activity of phytochemicals reported by various researchers. This paper describes antifungal activities of plant extracts and compounds against phytopathogenic fungi, approved botanical fungicides, their benefits, obstacles and mitigation strategies. Relevant sources were collected using online data bases such as Google Scholar, PubMed and Science Direct, and comprehensively reviewed for preparation of this manuscript. This review revealed that phytochemicals are effective to manage plant diseases caused by phytopathogenic fungi. Botanical fungicides are endowed with benefits such as resistance inhibition, being ecofriendly, effective, selective, and more affordable compared to synthetic fungicides. However, there are only small number of approved botanical fungicides due to the many challenges that hinder their adoption and utilization for a wider scale production. Farmers' reluctance, lack of standardized formulation techniques, strict legislation, rapid degradation, and other factors hinder their adoption and utilization. The ways to address these challenges include increasing awareness among farmers, conducting more research to identify potential plants with fungicidal properties, standardizing extraction and formulation techniques, implementing the idea of plant breeding to increase bioactive agents, identifying favorable environments for site-specific plant species production, discovering synthetic analogues of the active ingredient to maintain quality standards, establishing reasonable regulation procedures and price points for a quicker market introduction. To put all these into practice, we recommend collaboration of regulatory agencies and researchers from a variety of fields.

Due to their natural availability, biocompatibility, biodegradability, nontoxicity, flexibility, as well as improved structural and functional characteristics, pectin and pectin-based nanocomposites have become an interesting area of numerous researchers. Pectin is a polysaccharide that comes from plants and is used in a variety of products. The significance of pectin polysaccharide and its modified nanocomposites in a number of applications has been shown in numerous reviews. On their uses in pharmaceutical and medication delivery, there are, however, few review publications. The majority of papers on pectin polysaccharide do not structure their explanations of drug distribution and medicinal application. The biological application of pectin nanocomposite is also explained in this review, along with a recent publication. As a result, the goal of this review was in-depth analysis to summarize biological application of pectin and its modified nanocomposites. Due to their exceptional physicochemical and biological characteristics, pectin and its nanocomposites are remarkable materials for medicinal applications. In addition to enhancing the immune system, controlling blood cholesterol, and other things, they have been shown to have anticancer, antidiabetic, antioxidant, anti-inflammatory, immunomodulatory, and antibacterial properties. Because of their biocompatibility and properties that allow for regulated release, they have also received a lot of interest as drug carriers in targeted drug delivery systems. They have been used to administer medications to treat cancer, inflammation, pain, Alzheimer's, bacteria, and relax muscles. This review found that pectin and its derivatives have better drug delivery efficiency and are viable candidates for a wide range of medicinal applications. It has been advised to conduct further research on the subject of toxicity in order to produce commercial formulations that can serve as both therapeutic agents and drug carriers.

Genus Kniphofia and Aloe belong to Asphodeloideae and Alooideae subfamily of Asphodelaceae respectively. Asphodelaceae is a family of lily-related monocotyledonic flowering plants with 2 subfamilies, 16 genera and about 780 species distributed in arid and mesic regions of the temperate, subtropical and tropical zones of the old world, with the main center of diversity in southern Africa. The genus Kniphofia has about 70 species distributed in eastern and southern Africa, including the 7 species known to occur in Ethiopia, of which 5 species are endemic. Aloe is the largest genus among the Asphodelaceae family and it comprises of more than 400 species that are widely distributed in Africa, India, and other arid areas, with the major diversity in South Africa. The leaves of Kniphofia species are non-succulent, unlike the leaves of Aloe species. Aloe species are distinguished by having fleshy and cuticularized leaves usually with spiny margins. Kniphofia species have regular flowers with fused tepals while Aloe species have regular flowers with free tepals. Both Kniphofia and Aloe species have been employed in ethnopharmacology and have provided many bioactive compounds through phytochemical-pharmacological research works. They are traditionally used for treatment of various diseases by herbalists. Both genus elaborate naphthoquinone, preanthraquinone, anthraquinones and alkaloids in common. Additionally, Kniphofia elaborates benzene, naphthalene, and phloroglucinol derivatives while Aloe produces anthrones and chromones. The genus Kniphofia is rich in Knipholone type compounds while the genus Aloe is rich in anthrone-C-glycosides. Secondary metabolites isolated from the two genus have wide range of pharmacological activities such as antiplasmodial, anticancer, anti-inflammatory, antioxidant and antimicrobial activities. There is no published review article on the botanical description, traditional uses, phytochemistry, and pharmacological activities of the genus Kniphofia and only few review articles are available on the genus Aloe. In this review, an attempt is made to present pharmacological activities and secondary metabolites reported to date from genus Kniphofia and Aloe. Secondary metabolites reported from both plant genus have interesting biological activities so the authors of this review paper strongly recommend studies on toxicity of these compounds and their structural activity relationship so as to develop new pharmaceutical drug.