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Abstract

Aloe weloensis Sebsebe, a species used for therapeutic purposes in Ethiopia, exemplifies the plant's rich history of herbal use, traditional applications, and the need for further research. Aloe weloensis, a species of the Aloe genus, has gained attention for its potential pharmaceutical and therapeutic properties. This review examines the phytochemical composition, pharmacological effects, and pharmaceutical applications of Aloe weloensis. The methods involved a thorough review of published literature using reputable databases, focusing on English-language articles covering Aloe weloensis’ phytochemistry, antioxidant, antibacterial, and antimalarial activities. Aloe weloensis leaf latex demonstrates diverse bioactive compounds, antioxidant activity (IC₅₀: 10.25 μg/ml), significant antibacterial effects, and promising in vitro antimalarial activity (IC₅₀: 9.14 μg/ml) on 3D7 strains of Plasmodium falciparum species. In vivo studies support its potential as an antimalarial remedy, showcasing its multifaceted pharmacological profile. Aloe weloensis presents promising pharmacological properties, including antioxidant, antibacterial, and antimalarial activities, supported by its rich phytochemical composition. The in vivo antimalarial results and mucilage's potential as a suspending agent highlight its significance in modern medicine, warranting further exploration.

Keywords

pharmaceutical pharmacological and antibacterial activity

Introduction

Aloe, a genus within the Asphodelaceae family,¹ comprises 560 species and 21 infra-specific taxa.² Indigenous to Africa, the Arabian Peninsula, Madagascar, and the Mascarene Islands,³ Aloe has a rich history in herbal medicine. Extracting dried latex from its leaves has been a medicinal practice across continents.^4,5 Aloe species are known for their diverse therapeutic properties, including antibacterial, antitumor, anti-inflammatory, anti-arthritic, anticancer, and antidiabetic activities.⁶ This versatility extends to various commercial products such as laxatives, health beverages, tonics, after-shave gel, mouthwash, toothpaste, hair tonic, shampoo, and skin-moistening gel, highlighting Aloe's significance in traditional and modern applications.^7–9

Ethiopia, identified as a potential center of diversity for Aloe, boasts 46 documented species with three subspecies, of which 67.3% are exclusive to the region.^10,11 Ethno botanical studies conducted in aloe species showed that the most widely used parts of the plant was exudates and leaf extracts respectively. Different preparation methods were practiced by the local communities for medicinal application, the most common being pure exudate collection from the fresh leaf to be used for different application followed by pulverization and concoction.¹²

Aloe weloensis Sebsebe, named after the identifier Sebsebe Demissew, is one of the Aloe species found near Dessie in the Welo floristic region of North east of Ethiopia. The species is characterized by its thin, soft, and spotted leaves as shown in Figure 1 below, and it flowers from September to November in the wild. The habitat of Aloe weloensis is in the Welo floristic region of Ethiopia, specifically near Dessie. It is found on vertical rock faces, edges of rocky valleys, and on outcrops along rivers at an elevation of 1050-1500 m. As for its uses, the sap from its leaves is used to relieve pain from ear infections, and that warming the leaves and placing them on affected areas is reported to help against headaches and rheumatism.¹³ Another ethobotanical study has showed that the Aloe weloensis Sebsebe plant locally known with its name Eret tafa has been traditionally used by the community in the study area for different types of ailments; The leaves are chewed and drunk to relieve stomachaches; the latex is applied as paint to heal wounds; and the leaf is isolated and drunk to treat malaria.¹⁴

Figure 1.

Representative images of an Aloe weloensis Sebsebe.¹³

Aloe weloensis Sebsebe, a unique member of the Aloe genus, is gaining attention for its medicinal potential. Indigenous to specific regions, its distinctive aloin-rich leaves have been traditionally used for wound management, skin issues, and pain relief. Ongoing research into its phytochemical composition reveals bioactive compounds with anti-inflammatory, antimicrobial, and wound-healing properties. The research journey with Aloe weloensis holds promise for uncovering new therapeutic applications in contemporary medicine.¹³ This review aims to provide a comprehensive overview of the phytochemistry, pharmacological activities, and pharmaceutical applications of Aloe weloensis, shedding light on its journey from traditional folklore to modern scientific scrutiny. In doing so, we aim to contribute to the growing body of knowledge surrounding this remarkable plant, fostering a deeper understanding of its therapeutic potential and paving the way for innovative pharmaceutical applications.

Methods

This review conducted a thorough examination of published literature, employing a web-based search strategy to investigate the phytochemistry, pharmacological, and pharmaceutical applications of Aloe weloensis sebsebe. The search encompassed reputable scientific databases such as Pub Med, Science Direct, Web of Science, research gate, and Google Scholar with inclusion criteria of published full-length articles in the English language covering geographical distribution, phytochemistry, antioxidant activity, antimalarial activity, antibacterial activity, and pharmaceutical applications related to Aloe weloensis with exclusion criteria of data from historical documents or non-experimental studies, data from non-open access journal articles or partially accessed. The following key words were used including “Aloe weloensis,” “anti-oxidant, antimalarial and antibacterial activity,” phytochemistry” “ethnobotany/ethobotanical,” “ethnopharmacology,” and related terms, ensuring a comprehensive exploration of the literature.

Phytochemistry of Aloe Weloensis Sebsebe

Phytochemical studies involve the analysis of plant constituents, including secondary metabolites, which contribute to the plant's medicinal properties. These compounds can include alkaloids, flavonoids, terpenoids, saponins, and others.

Anthraquinones, glycosides, saponins, terpenoids, tannins, phenol, and flavonoids were found in Aloe weloensis leaf latex (Figure 2), according to a phytochemical analysis conducted on the plant using several tests; alkaloids were not present in the plant's leaf latex.¹⁵ In contrast, another study found that the plant's latex leaves contained alkaloids.¹⁶ The variation in absence and presence of these chemical constituents is based on the plant part used, extraction process, solvent, stage of growth, collection period, method of extraction and plant source. In addition the plant was shown to contain a mucilage (the ruthenium red test) as indicated by a study conducted by Mengesha et al¹⁷ The researches done on the photochemistry look inadequate and the scholars on the filed should focus on the quantitative compositions of the different bioactive of this plant and the isolation and characterization of the specific types of phytochemicals present.

Figure 2.

The chemical structures of commonly available phytochemicals from most aloes. (A). Anthraquinones, (B). Glycosides, (C). Aloin, (D). Flavonoids.

Collection of the Leaf Latex

Leaf latex of Aloe weloensis was collected by cutting the leaves transversely near the base and allowing the yellow sap to come down in a plastic material left in an open air to allow evaporation of water and collection of pale yellow latex.^15,16

Extraction of the Mucilage

Aloe mucilage is typically extracted from the leaves of the Aloe weloensis plant. These leaves are cut to obtain the mucilaginous substance. The cut leaves are homogenized with water in a blender. This process helps break down the cellular structure of the leaves and extract the mucilage into the water. After homogenization, the mixture is strained to remove excess water. This step is likely done to isolate the mucilage from the liquid portion. The mucilage is then precipitated from the solution by soaking it in diethyl ether. Precipitation often involves using a less polar solvent to separate the mucilage from the water. The precipitated gum is filtered using a suction filter. This step helps separate the precipitated mucilage from the solvent. The filtered mucilage is spread out and allowed to dry in the air. After this initial drying, the sample is then oven-dried at 40 °C for 4 h. Drying is crucial for obtaining a stable form of the mucilage. The dried mucilage is pulverized, possibly to obtain a fine powder. This step is important for ease of handling and storage. The pulverized mucilage is passed through a sieve with a specified mesh size (224 µm in this case). Sieving helps ensure uniform particle size. The sieved and pulverized mucilage is stored in a desiccator (a container for drying substances) in an airtight glass bottle. This step helps preserve the quality of the mucilage for future use.^17,18 Nowadays we have more efficient alternative extraction techniques than the traditionally used solvent based methods including microwave-assisted extraction, ultrasonic-assisted extraction, enzyme assisted extraction which can effectively extract the natural substances.¹⁹ The efficiency of extraction, separation and purification of the compounds will be affected by many factors related to each variable.²⁰

This detailed extraction process ensures the isolation of Aloe mucilage in a form suitable for various applications, such as in pharmaceuticals, cosmetics, or other industries where Aloe mucilage is utilized (Figure 3).

Figure 3.

Extraction techniques: A. The fresh leaves of Aloe weloensis collected will be washed with water; B. The yellowish mucilage obtained from the cut leaves will be homogenized and strained to remove excess water; C. The mucilage will be precipitated from the slake by soaking in diethyl ether,; D. it will be filtered by suction filter then spread and allowed to dry in the air before oven drying at for 4 h.

Pharmacological Activities

Acute Toxicity Study

Though beneficial, some of phytochemicals may be associated with toxic effects. Many researchers have established potential toxicities as well as risks associated with some plants and vegetables particularly hepatotoxicity, nephrotoxicity, and cancer. Due to these risks, toxicological evaluation of medicinal plants has become one of the main concerns to assure their safe use.^21,22

The acute toxicity of Aloe weloensis is evaluated in a study using OECD guidelines, and no signs of toxicity including loss of appetite, hair erection, lacrimation, tremors, convulsions, salivation, diarrhea, and mortality during the experiment were observed at 5000 mg/kg. Effective doses for the main experiment were identified at 200, 400, and 600 mg/kg, indicating the plant's potential as a therapeutic agent with a favorable safety profile.²³ In another study which delivered a starting dose of 2000 mg/kg of the Aloe welonsis leaf extract. Acute toxicity study indicated that the leaf latex of Aloe weloensis did not cause mortality of mice within 24 h of treatment, as well as during 14 days. Gross physical observation of mice revealed no visible signs.¹⁵ The difference in the starting dose for acute toxicity may be due to the difference in the weight of the mice taken. In one study by Teka et al, the weight ranges from 20 to 350 grams, while the study by Amare et al does not mention the weight.

Antioxidant Properties

Antioxidants are substances that help neutralize harmful free radicals in the body, and they play a role in protecting cells from oxidative stress. The antioxidant activity of Aloe weloensis leaf latex can be attributed to the presence of bioactive compounds such as phenolic compounds, flavonoids, and other phytochemicals, which are known for their ability to scavenge free radicals and exhibit antioxidant properties. These compounds contribute to the plant's ability to inhibit free radicals and demonstrate antioxidant activity.

In one study in vitro antioxidant activity of the leaf latex Aloe weloensis was evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl) -free radical scavenging assay following the method of MacDonald-Wicks et al by suing ascorbic acid as a standard.²⁴ Qualitative detection showed that the color of the test solution changed from violet to a slightly yellow color. The research indicated that the IC₅₀ value of the antioxidant activity of the leaf latex of Aloe weloensis was 10.25 μg/ml, while the IC₅₀ value of ascorbic acid, used as a standard antioxidant, was 2.97 μg/ml which was showed to be by far a lower IC₅₀ and better antioxidant activity than Aloe adigratana²⁵ and Aloe debrana²⁶ with IC₅₀ of 82 and 32 μg/ml respectively (Table 1) which may be attributed to the difference in phytochemicals, part of the plant used and the method of extraction and solvent employed. Moreover, the crude extract could be accounted to the synergistic interactions of several secondary metabolite than the isolated compounds in the latter aloe species. This suggests that the antioxidant activity of the plant latex is lower compared to the standard ascorbic acid.²⁷

Table 1.

Phytochemicals and Pharmacologic Activity of Aloe weloensis as Compared with the Common aloe species in Ethiopia and the World.

Aloe spp.	Plant parts used	Phytochemicals available	Pharmacologic activity	Results of the activities	references
Aloe weloensis	Leaf latex	Anthraquinones, glycosides, saponins, terpenoids, tannins, phenol, and flavonoids	Anti-oxidant, Anti-bacterial, Anti-malarial	13% to 66% parasitemia inhibition, dose dependent anti-bacterial activity with the highest dose showing around 26 mm zone of inhibition and significant anti-oxidant activity with IC₅₀ of 10 µg/ml.	^15,16,23
Aloe adigratana Reynold	Leaf gel	flavonoids, tannins, phenolic compounds, and terpenoid	Anti-oxidant	IC₅₀ values were 82.62 μg/ml	²⁵
Aloe elegans	Leaf gel	Anthraquinones, Flavonoids, Saponins and Tannins	Anti-microbial	Better zone of inhibition about 22 mm with sensitive s.aures	³⁰
Aloe percrassa Todaro	Leaf latex	Anthraquinones, Flavonoids, Saponins, Glycosides, Tannins, Phenols and Alkaloids	Anti-malarial	45.9%, 56.8% and 73.6% parasitemia suppression	³⁵
Aloe debrana	Leaf latex	flavonoids, tannins, phenolic compounds, and terpenoid	Anti-malarial, anti-bacterial and anti-oxidant	Showed a parasite suppression of 35.49, 47.02 and 63.13% at different doses, no toxicity up to 5000 mg/kg, anti-oxidant IC ₅₀ from 20 to 32 µg/ml, 91 mm zone of inhibition against s. aures	^26,36
Aloe vera	Leaf gel	Tannins, Saponins, flavonoids, anthraquinones, terpen-oids, steroids, alkaloids, Carbohydrates, Glycoside	Anti-oxidant	inhibits the generation DPPH and the scavenging activity was increased in a dose dependent manner	³⁷

The IC₅₀ (half maximal inhibitory concentration) measures the effectiveness of a substance in inhibiting a biological function by 50%. In antioxidant research, IC₅₀ assesses the concentration of plant extracts or compounds needed to inhibit 50% of an oxidative process, reflecting their ability to scavenge free radicals or reactive oxygen species (ROS). A lower IC₅₀ value indicates higher antioxidant activity, meaning less substance is needed to achieve 50% inhibition. Researchers use various assays, like DPPH or ABTS, to determine IC₅₀ values and compare antioxidant potential among substances based on their specific research goals.²⁷

The recent data on the antioxidant activity of Aloe weloensis leaf latex presents promising results, indicating a concentration-dependent antioxidant capacity with an IC₅₀ value of 10.25 μg/ml. This suggests that Aloe weloensis has the potential to scavenge free radicals effectively. The study also demonstrated significant inhibition of Plasmodium falciparum growth in culture, further highlighting the plant's therapeutic potential. Future research could explore the mechanisms underlying the antioxidant properties of Aloe weloensis, investigate its potential synergistic effects with existing antimalarial drugs, and assess its efficacy in clinical trials for malaria treatment. Additionally, exploring the bioactive compounds responsible for the antioxidant activity could lead to the development of novel antioxidant-based therapies for various health conditions.

Antibacterial Effects

The assessment of antibacterial activity in plants involves testing plant extracts or compounds for their ability to inhibit the growth of bacteria. This is often done using various laboratory methods. Antibiotic resistance and the potential for adverse effects from conventional antibacterial drugs are major challenges that researchers and healthcare professionals are actively addressing.²⁸

The exploration of newer antibacterial agents from plant extracts is one avenue of research that holds promise. Plants have been used in traditional medicine for centuries, and many of them contain bioactive compounds with potential antibacterial properties. Natural products, including those derived from plants, are often perceived as having a lower risk of adverse effects compared to synthetic drugs. However, it's essential to note that even natural compounds can have side effects, and thorough research is necessary to understand their safety and efficacy. Plants produce a wide array of secondary metabolites, such as alkaloids, flavonoids, terpenoids, and polyphenols, which may exhibit antibacterial properties. These compounds can interfere with bacterial cell processes, leading to growth inhibition or cell death.²⁹

One study evaluated the antibacterial effect of Aloe weloensis leaf latex at different concentrations (400, 500, and 600 mg/ml) against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus fecalis) bacterial strains by using disc diffusion technique where filter paper discs containing the plant extract are placed on the agar surface. Again, zones of inhibition were measured and compared with the positive standard which was ciprofloxacin (5 μg/disc). The results showed significant antibacterial activity at all tested concentrations, with the highest dose (600 mg/ml) demonstrating the maximum activity. Aloe weloensis leaf latex showed promise as a source of antibacterial chemicals that could combat both Gram-positive and Gram-negative bacterial strains. Further investigation of isolated compounds from the leaf latex is recommended to discover efficient antibacterial agents for treating infectious diseases caused by pathogenic bacterial strains and potentially addressing antibiotic-resistant bacterial strains. The tested concentrations of the latex ranging between 400 and 600 mg/ml showed significant antibacterial activity against bacterial strains, with the highest dose (600 mg/ml) of Aloe weloensis leaf latex revealing the maximum activity (25.93 ± 0.066 inhibition zone) followed by the dose 500 mg/ml against Staphylococcus aureus which is again better than Aloe elegans³⁰ with zone of inhibition 22 mm with similar test microorganism but lower than Aloe debrana²⁶ with zone of inhibition of 91 mm (Table 1). the difference may be attributed to the variation in the concentration used, the standard drug and the technique. The lowest antibacterial activity was observed by the concentration 400 mg/ml (5.03 ± 0.03) against E. coli).¹⁶

Aloe weloensis leaf latex has the potential to be utilized in the creation of safe, economical, and effective antibacterial agents that might be used in conjunction with or instead of traditional medications. The study presented above suggests that the leaf latex of Aloe weloensis can be used as potential leads to discover new drugs to control some bacterial infections. The antibacterial activities revealed by Aloe weloensis were effective enough against Gram-positive and Gram-negative bacterial strains. The results of this study are encouraging and confirm the pursuit of new active compounds in Aloe weloensis responsible for its antibacterial potential. Therefore, further antibacterial activity investigation of isolated compounds from the leaf latex of Aloe weloensis is highly warranted to pave the way to discover an efficient antibacterial agent that can be used alone or in combination with conventional antibiotics to treat infectious diseases caused by pathogenic bacterial strains and possibly to treat resistance bacterial strain.

While plant extracts show promise, there are challenges in terms of standardization, quality control, and understanding the mechanisms of action. Additionally, the potential for variability in bioactive compound content among plant samples and issues related to pharmacokinetics need to be addressed. Future research in this area could focus on elucidating the specific bioactive compounds present in Aloe weloensis leaf latex responsible for its antibacterial activity. Understanding the mechanisms of action of these compounds could lead to the development of novel antibacterial agents or formulations. Additionally, exploring the potential synergistic effects of Aloe weloensis with conventional antibiotics could provide insights into combination therapies to combat multidrug-resistant bacterial strains. Furthermore, investigating the potential applications of Aloe weloensis in different forms such as topical creams, wound dressings, or oral supplements could open up new avenues for its use in clinical settings. Collaborative efforts between researchers, pharmacologists, and traditional medicine practitioners may help bridge the gap between traditional knowledge and modern scientific validation, paving the way for the development of effective and safe antibacterial treatments derived from natural sources like Aloe weloensis.

Antimalarial Activity

Traditional medicine can play a significant role in the development of new cost-effective anti-malarial drugs, especially in developing countries like Ethiopia where the populations cannot afford high-priced drugs.³¹

The exploration of natural sources for antimalarial compounds has been a subject of extensive research, driven by the urgency to combat malaria, a deadly infectious disease affecting millions worldwide. Plants, with their rich chemical diversity, have been a traditional source of medicinal remedies for centuries. In recent years, scientific interest has focused on identifying and understanding the antimalarial properties of bioactive compounds derived from various plant species. These compounds, often exhibiting unique chemical structures, offer a potential arsenal in the fight against malaria. The pursuit of plant-based antimalarial agents is grounded in both the historical significance of plant-derived remedies and the need for novel, effective, and potentially more affordable treatments to address the challenges posed by drug-resistant malaria parasites. This exploration integrates traditional knowledge with modern scientific methodologies to uncover promising botanical candidates for the development of new antimalarial drugs.³²

in Vitro Antimalarial Activity of Aloe weloensis

This pharmacological test is by far the most extensively studied activity on Aloe welonesis. The in vitro antimalarial activity of the leaf latex of Aloe weloensis against the 3D7 strain of Plasmodium falciparum revealed promising results. The study found that the leaf latex demonstrated concentration-dependent antimalarial activity, with an IC₅₀ value of 9.14 μg/ml. This indicates that at a concentration of 9.14 μg/ml, the leaf latex was able to inhibit 50% of the growth of the Plasmodium falciparum 3D7 strain in the in vitro assay. Comparatively, the standard drug chloroquine exhibited a much lower IC₅₀ value of 0.02 μg/ml, indicating its higher potency as an antimalarial agent.³³ These findings suggest that the leaf latex of Aloe weloensis possesses significant in vitro antimalarial activity against the tested strain of Plasmodium falciparum, albeit with a higher IC₅₀ value compared to chloroquine. This highlights the potential of Aloe weloensis as a source for the development of novel antimalarial drugs, especially considering its natural origin and concentration-dependent activity.

Whereas the methanolic extract of Aloe weloensis leaf latex was found to be inactive against both the chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum, with an IC5₀ value greater than 200 μg/ml. This indicates that the extract did not exert suppressive activity on the growth of the Plasmodium falciparum strains. Additionally, the leaf latex of Aloe weloensis was found to have inactive molecules that may require biological transformation (metabolism) into active molecules, suggesting the possibility of it being a pro-drug.³⁴ The difference in the results of the two studies may emanate from the source of the Plasmodium falciparum strain used in the respective studies.

in Vivo Antimalarial Activity of Aloe weloensis

In one study done by Teka et al, the leaf latex of Aloe weloensis exhibited a significant reduction in parasitemia in a dose-dependent manner as compared to the negative control in the 4-day suppressive test. The leaf latex of Aloe weloensis exhibited a percent inhibition of 13.05%, 41.87%, and 66.84% at doses of 100 mg/kg, 200 mg/kg, and 400 mg/kg, respectively. This parasitemia reduction was lower as compared with Aloe percrassa Todaro³⁵ and higher when compared with Aloe debrana³⁶ with 74% and 63% at maximum dosage respectively (Table 1). The basic rationale behind this differences can be compounds in the crude extract exert their actions synergistically or there may be other minor components in the latex which have stronger schizonticidal activity. The antimalarial activity of the plant might be related to the presence of terpenoids, flavonoids, anthraquinones, glycosides, saponins, and tannins which might act singly or in combination against Plasmodium berghei infection¹⁵ where as in another study conducted by Amare et al, the antimalarial activity of Aloe weloensis was tested by using both prophylactic and suppressive tests. The in vivo evaluation of Aloe weloensis leaf latex demonstrated significant antimalarial activity in both prophylactic and curative models. The leaf latex showed dose-dependent reduction in parasitemia levels, with the highest doses (400 and 600 mg/kg) exhibiting the most significant effects. Additionally, the leaf latex improved the mean survival time of the infected mice. These findings support the traditional use of Aloe weloensis as an antimalarial remedy and suggest its potential as a source of novel antimalarial compounds²⁷ (Table 2). Overall, the study suggests that Aloe weloensis possesses promising antimalarial activity and might contain potential lead compounds for the development of novel antimalarial drugs. The recent data on the anti-malarial activity of Aloe weloensis leaf latex presents compelling evidence of its efficacy against Plasmodium berghei in mice, showcasing significant parasitemia reduction in a dose-dependent manner without causing toxicity at doses up to 2000 mg/kg. The presence of bioactive compounds such as terpenoids, flavonoids, anthraquinones, glycosides, and saponins in the plant suggests a potential mechanism of action against malaria parasites. These findings support the traditional use of Aloe weloensis for malaria treatment and highlight its potential as a source of novel antimalarial compounds. Future research could focus on elucidating the specific bioactive components responsible for the antiplasmodial activity, optimizing dosage regimens, and exploring synergistic effects with existing antimalarial drugs to enhance therapeutic outcomes and pave the way for the development of new antimalarial treatments.

Table 2.

Summary of the in Vivo Anti-Malarial Activity of Aloe weloensis Tested.

Type of antimalarial test	LD₅₀	Dose of the extract	ParasitemiaInhibition	Strain of plasmodium tested	References
Curative	2000mg	100 mg 200 mg 400 mg	13% 41.87% 66.84%	Plasmodium berghei	¹⁵
Curative	5000 mg	200 mg 400 mg 600 mg	36.17% 57.69% 73.5%	Plasmodium berghei	²³
Prophylactic	NA	200 mg 400 mg 600 mg	37.87% 46.29% 56.68%	Plasmodium berghei	²³

Note: LD₅₀ is not applicable (N/A) for the Prophylactic test, as LD₅₀ typically refers to the lethal dose, and prophylactic tests focus on prevention rather than lethality.

Pharmaceutical Applications

Plant mucilages, also known as plant gums or exudates, play a crucial role in various biological functions and have gained attention for their versatile applications in different industries. Among their many functions, one notable role is their effectiveness as a suspending agent. Plant mucilages are complex polysaccharides produced by various plants, and their unique properties make them valuable in forming stable suspensions. In suspension science, the role of a suspending agent is to prevent the settling of solid particles in a liquid medium, maintaining a uniform dispersion.

A study conducted by Mengesha et al, showed that the suspending agent capabilities of mucilage obtained from Aloe weloensis leaves with acacia reveals intriguing insights into their potential applications. The study compared Aloe weloensis mucilage to acacia as a suspending agent, finding comparable performance at 1% and 4% concentrations, with slightly higher sedimentation and viscosity than acacia, though not statistically significant (p > 0.05). Aloe weloensis mucilage demonstrated unique characteristics, being slightly basic and easily dispersible compared to sodium carboxymethyl cellulose (NaCMC). However, NaCMC suspensions outperformed acacia and Aloe weloensis mucilages in terms of viscosity and sedimentation volume, with statistically significant differences (p < 0.05). Despite this, the study suggests that Aloe weloensis mucilage could serve as an alternative suspending agent, particularly in formulations where its specific properties are advantageous.¹⁶

The recent study on the evaluation of Aloe weloensis mucilages as a pharmaceutical suspending agent presents promising results, indicating that Aloe weloensis mucilage exhibits comparable suspending qualities to standard materials like acacia and NaCMC. The high sedimentation volume and ease of redispersibility of Aloe weloensis mucilage suggest its potential as a natural alternative for pharmaceutical formulations. Future research could focus on exploring the stability and compatibility of Aloe weloensis mucilage in pilot-scale formulations, addressing any machine constraints that were encountered in the current study. Additionally, investigating the specific mechanisms by which Aloe weloensis mucilage functions as a suspending agent and its potential applications in various pharmaceutical products could provide valuable insights for the industry.

Challenges and Future Perspectives

One major challenge is the limited amount of research conducted on Aloe weloensis compared to more widely studied Aloe species. This scarcity of data hampers a comprehensive understanding of its pharmacological, phytochemical, and pharmaceutical properties. Aloe weloensis is indigenous to specific regions, and accessibility to these areas may pose challenges for researchers. Limited availability of plant specimens and difficulties in conducting field studies may impede thorough investigations. Standardization of methodologies for phytochemical analysis and pharmacological assays is crucial for reliable comparisons between studies. However, the lack of standardized protocols for Aloe weloensis research may result in inconsistencies in reported findings. Aloe weloensis may exhibit considerable intraspecific diversity, leading to variations in chemical composition and pharmacological activities. Understanding and accounting for this diversity is essential but challenging.

Future research should focus on more in-depth phytochemical studies to identify and isolate specific bioactive compounds in Aloe weloensis. This can provide a foundation for understanding its potential medicinal properties. Comprehensive studies on the biosafety and potential toxicity of Aloe weloensis extracts or compounds are essential for ensuring the safety of its pharmaceutical applications. The local communities, and pharmaceutical industries can contribute to a more holistic approach in studying and utilizing the potential benefits of Aloe weloensis.

Conclusion

In conclusion, Aloe weloensis emerges as a promising botanical resource with diverse pharmacological activities, including antioxidant, antibacterial, and antimalarial properties. The phytochemical composition underscores its potential therapeutic value. The in vivo antimalarial activity supports traditional use, suggesting Aloe weloensis as a source for novel antimalarial compounds. Additionally, its mucilage shows promise as an alternative suspending agent. This comprehensive exploration opens avenues for further research, emphasizing the potential of Aloe weloensis in modern medicine.

Footnotes

Availability of Data and Materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Consent for Publication

Use of information for academic purposes is authorized.

Declarations

All authors declared that, this review article is the original work, has not received prior publication and isn't under consideration for publication elsewhere.

Declaration of Conflicting Interests

The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Yohannes Mengesha

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A Review on Aloe weloensis: Unveiling its Phytochemical Composition and Promising Pharmacological Properties in Antioxidant,Antibacterial,and Antimalarial Activities

Abstract

Keywords

Introduction

Methods

Phytochemistry of Aloe Weloensis Sebsebe

Collection of the Leaf Latex

Extraction of the Mucilage

Pharmacological Activities

Acute Toxicity Study

Antioxidant Properties

Antibacterial Effects

Antimalarial Activity

in Vitro Antimalarial Activity of Aloe weloensis

in Vivo Antimalarial Activity of Aloe weloensis

Pharmaceutical Applications

Challenges and Future Perspectives

Conclusion

Footnotes

Availability of Data and Materials

Consent for Publication

Declarations

Declaration of Conflicting Interests

Funding

ORCID iD

References