Abstract
Background: Agave angustifolia (AA) and Agave sisalana (AS) are used by local communities for medicinal purposes to treat skin conditions. Small companies add Agave leaf extracts to their cosmetic products, claiming calming and skin-rejuvenating qualities.
Aim: The study aimed to assess the phytochemical profiles and antioxidant activities of AA and AS verifying the traditional therapeutic claims about the species and accordingly establishing the assertions of cottage industries.
Setting: The AA leaves were collected from the eThekwini Metropolitan Municipality, while AS leaves were sourced from the iLembe district municipality.
Methods: The phytochemical extracts were obtained by gradient solvent maceration of the leaves. Qualitative phytochemical screening established the presence of bioactive phytochemicals in the extract. The 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and the ferric reducing and/or antioxidant power (FRAP) methods measured the bioactive phytochemicals’ antioxidant activity.
Results: Qualitative phytochemical evaluation confirmed the presence of secondary metabolites in both plants. AS extracts also contained alkaloids. The DPPH antioxidant activity indicated that Agave extracts had 20% to 80% scavenging activity. AS methanol extract had the maximum antioxidant activity among all the extracts. AA methanol and AS hexane extracts had no antioxidant activity. AA ethyl acetate extract had higher antioxidant activity (64%) than AS (52%). AA hexane extract had 70% activity while AS hexane extract had 30%.
Conclusion: The detected phytochemicals indicate potential use for emulsifying, antioxidant, anti-ageing, anti-inflammatory, and broad-spectrum antimicrobial activities.
Contribution: This study contributes to the existing knowledge of the therapeutic properties of AA and AS plants.
Keywords: Agave; angustifolia; sisalana; bioactive phytochemicals; therapeutic value; bioactivity; cosmetics.
Introduction
The Agave genus is indigenous to America (Cruz-Magalhães et al. 2020; Rivera-Lugo et al. 2018), but has spread throughout the world and is now found in South Africa, Swaziland, Angola, Brazil, China, and other countries (Cruz-Magalhães et al. 2020; Villanueva-Rodríguez et al. 2016). The Agave genus is made up of more than 200 species (Ahumada-Santos et al. 2013; Cruz-Magalhães et al. 2020; Salazar-Pi et al. 2017; Villanueva-Rodríguez et al. 2016), and examples include Agave angustifolia, Agave salmiana, Agave sisalana, Agave americana, Agave tequilana, and others (Rivera-Lugo et al. 2018). The Agave plants have big, fibrous leaves (López-Romero et al. 2018) and are morphologically very similar, making it difficult for some local people to differentiate them.
Although alien to South Africa, the Agave plants have found many uses in the local KwaZulu-Natal (KZN), South African community, such as building hedges and in traditional medicine. In Mexico, Agave plants are used for various things, including food, construction, medicine, textiles, and decoration (Rivera-Lugo et al. 2018). Agave-based alcoholic beverages are trendy both in Mexico and around the world. Agave tequilana and A. angustifolia are used to manufacture alcoholic beverages, tequila and bacanora, respectively. A. salmiana, A. cupreata, A. duranguensis, A. fourcroydes, A. angustifolia, A. potatorum are used in the manufacture of mezcal (Vera-Guzmán et al. 2018). The ecological significance of Agave plantsis derived from their capacity to prevent soil erosion through their root network, manage precipitation runoff, sequester carbon dioxide and provide food and shelter to various animal species and insects (Almazán-Morales et al. 2022). Traditionally, Agave plants have been used to treat bacterial-induced health disorders and free elemental xenobiotic-induced toxicity (Bhattacharyya et al. 2014). The disorders may include inflammations, wound infections, cancer, and others (Ahumada-Santos et al. 2013). Literature suggests that Agave plants have extensive, scientifically demonstrated traditional uses, such as digestive and wound infections (Villanueva-Rodríguez et al. 2016). Pharmacological research has confirmed the anti-inflammatory properties of various Agave species, primarily because of terpenes and steroidal saponins (Monterrosas-Brisson et al. 2013). A. americana, A. angustifolia, A. cupreata, A. sisalana, and A. tequilana are used to treat inflammatory-related ailments and are known to display antifungal, antihypertensive, anti-inflammatory, antiparasitic, and immunomodulatory actions (Ahumada-Santos et al. 2013; Monterrosas-Brisson et al. 2013; Salazar-Pi et al. 2017). Research on the Agave genus has long recognised different Agave species as a reliable source of steroidal saponins (Mina et al. 2013).
The Agave species of interest in this study are two wild Agave plants abundantly found in KwaZulu-Natal province, South Africa: A. sisalana Perrine and A. angustifolia Haw. var. angustifolia. The leaves of these two species are used traditionally by the community in treating various ill health, particularly skin conditions. The study, therefore, investigates the leaf extracts’ phytochemical screening and their antioxidant activities to substantiate the plants’ folk therapeutic claims. The problems in this study are that several Agave plant species are physiologically too similar, but exhibit different biological traits. An example is the similarities of A. angustifolia and A. americana, as well as A. tequilana and A. sisalana. The close resemblance makes it difficult for local users to differentiate the species. The species’ close physiological similarity often confuses selecting the appropriate species for the treatments, resulting in poisoning of the patient rather than curing. Another problem is the lack of literature on safe and effective doses for agave use in personal care applications.
Agave angustifolia Haw is an evergreen, perennial shrubby, succulent plant. It has stiffly erect, slender leaves with spaced-apart spikes and a sharp prickle at the end (Verloove et al. 2019) (Figure 1a). According to Verloove and Pascual (2021), A. angustifolia is a varied species that is endemic to Central America and is mainly used to make mezcal (Vera-Guzmán et al. 2018), as well as ropes, fuel, and decorations (Franck 2012; García-Mendoza & Chiang 2003). Agave angustifolia has a wide range of applications in conventional medicine. While the boiled leaves, sap, and root infusions have been used to make bandages for injuries and inflammation and to heal ‘internal injuries’, the fibre is used to treat urticaria (García-Mendoza & Chiang 2003). According to García-Mendoza and Chiang (2003), the roots have diuretic and diaphoretic properties. Therefore, a remedy made from boiling the root has been used to treat dysentery. Agave angustifolia is also employed for sprains and broken bones in people and animals, as the roasted A. angustifolia leaves are applied topically to treat sprains and fractured bones, as well as to reduce rheumatic pain (Jiménez-Ferrer et al. 2022). It is suggested that applying fresh A. angustifolia leaves to wounds can help reduce bleeding and pain (Hernández-Valle et al. 2014; Monterrosas-Brisson et al. 2013). Food supplements containing agavins from A. angustifolia are utilised (Velázquez-Martínez et al. 2014) because the leaves of the A. angustifolia plant have antioxidant qualities and are rich in phytosterols and steroidal saponins (Ahumada-Santos et al. 2013; Hernández-Valle et al. 2014). Coughs and skin problems, such as acne, can be treated with fresh A. angustifolia leaves, and the roasted leaves are applied topically to treat sprains and fractured bones and reduce rheumatic pain (Jiménez-Ferrer et al. 2022). Literature suggests that the sap from A. angustifolia is applied topically to humans and animals to treat sprains and fractured bones (Monterrosas-Brisson et al. 2013).
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FIGURE 1: Agave angustifolia (a) and Agave sisalana (b) plants. |
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Agave sisalana Perrine (AS), popularly known as sisal, belongs to the Agavaceae family (Chigodi et al. 2013; Zwane, Dlamini & Nkambule 2010). It has sword-shaped, stiff, smooth-edged grey-green leaves with a sharp spike at the tip (Figure 1b). It was first brought to Tanzania in 1893, and then it spread to other regions of East Africa for fibre production from the sisal leaves (Chigodi et al. 2013). It is currently found in numerous tropical nations, such as South Africa, Tanzania, Uganda, Mozambique, and Namibia (Zwane et al. 2010). The researchers have reported that A. sisalana has anthelmintic, antibacterial, analgesic, and anti-inflammatory properties (Guimarães de Oliveira et al. 2016). Wu et al. (2021) reported that the pharmaceutical industry uses hecogenin, a sapogenin isolated from A. sisalana leaves, for pharmaceutical developments. The images of A. angustifolia and the A. sisalana plants taken by the researcher from the research site are shown in Figure 1.
Plants contain naturally occurring physiologically active chemical compounds, known as phytochemicals, that offer human health advantages beyond those of macro- and micro-nutrients (Araldi et al. 2018). They are found in a variety of foods, including fruits, vegetables, whole grains, legumes, nuts and seeds, tea, and dark chocolate, and only a small number have been isolated and identified from the plants (Xiao & Bai 2019). These phytochemicals, found in various plant parts, are well-known to possess anti-ageing, anti-inflammatory, and antioxidant properties (Michalak 2022; Roy et al. 2022). Scientific research has demonstrated the effectiveness and safety of these properties in preventing skin health issues such as photoaging and treating atopic dermatitis (Michalak 2022; Wu et al. 2021). These bioactive phytochemicals include carotenoids, phenolic acids, alkaloids, terpenes, tannins, and phytosterols. They are responsible for the plant’s anti-inflammatory, antibacterial, antifungal, and antioxidant properties (Xiao & Bai 2019). Research has reported that polyphenols have good activity as antioxidants, anti-inflammatory, and anti-cancer agents that prevent cardiovascular diseases (Briguglio et al. 2020). Plant phenolics protect against environmental strains such as UV radiation, pathogenic infection, and predators (Kumar et al. 2020). The two most used methods to determine antioxidant activity are the 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and ferric reducing or antioxidant power (FRAP) assays. This study evaluated the two selected wild Agave plants’ phytochemical profile and their antioxidant activity to establish the plants’ extracts’ suitability and potential use in cosmetic product development.
Research method and design
Plant collection and identification
The A. angustifolia leaves were collected from the Isipingo beach suburb (29°59’44.0”S 30°56’38.0”E), located on the southern coast of KZN, South Africa, under the eThekwini Metropolitan Municipality. In contrast, the AS leaves were collected from the veld along the R34 road (29°27’29.6”S 31°04’30.9”E), under the iLembe district municipality, KZN, South Africa.
The South African National Biodiversity Institute (SANBI) verified the taxonomic identity of the plants, and the two samples were added to the KZN Herbarium with the accession numbers A. sisalana (152364) and A. angustifolia (152365).
Sample preparation and extraction
To avoid injuring the sampler, the atopic, harmful spiky points of the leaves were removed before cutting both the A. angustifolia and the A. sisalana leaves. The cut leaves were transported to the laboratory, where side thorns on the A. angustifolia leaves were removed, and these leaves were washed with tap water to remove dirt, rinsed with distilled water, and arranged on a paper towel to remove excess water. The leaves were then cut into tiny pieces and spread in a fume hood (on a paper towel) to dry for a week. The dried Agave leaves were ground into a fine powder and put in a sterile, airtight plastic zip-lock bag before being placed in the cabinet to await the analysis’ subsequent stage.
Cold maceration was used to extract the 2 kg of finely crushed Agave leaves over 72 h at room temperature, with occasional stirring. The solvents used were non-polar hexane, polar ethyl acetate, and most polar methanol (Dharajiya et al. 2017). The plant material was sequentially extracted with solvents, with increasing polarity, ranging from hexane to methanol to obtain different solvent extracts. Two kilogram of the pulverised Agave sample was soaked in 1.5 L of hexane and covered with foil to prevent solvent evaporation, as well as ingress of foreign matter. It was ensured that the powdered material was covered by the solvent to ensure maximum extraction.
The leaves were macerated for 72 h in the fume cupboard, with daily stirring to ensure maximum extraction, filtered, rinsed with hexane, and the filtrate was put aside. The residue was soaked in ethyl acetate for 72 hours. After, it was filtered, then washed with the same solvent, and the solvent was removed with rotatory evaporator. The residue was soaked in methanol for 72 hours, after which it was filtered and rinsed with the same solvent. The solvent was removed with rotatory evaporator.
The IKA RV10 digital rotatory evaporator was used to concentrate the filtrates under reduced pressure, and the extracts were kept at 4 °C for the following experiment stage.
Phytochemical screening of Agave plant extracts
The Agave leaf extract underwent a preliminary phytochemical evaluation, employing standard methods to identify the presence of various phytochemicals with minor modifications (Dharajiya et al. 2017).
Test for flavonoids
Sodium hydroxide test: 2 mL of 2.0% NaOH solution added to 1 mL of Agave extract produced a prominent yellow hue that disappeared when two drops of mild acetic acid were added, indicating the presence of flavonoids.
Test for tannins
The Agave extract (0.5 g) and 10 mL of water were combined and placed in a test tube. After boiling and filtering the mixture, a small amount of 0.1% ferric chloride was added and stirred, and the colour of the mixture was examined for a blue-black or greenish-brown hue, which indicates the presence of tannins.
Test for phenols
Ellagic test: After adding five drops of 5% FeCl3 to 1 mL of plant extract, a yellow-green fluorescence was observed, indicating the presence of a specific phenol called resorcinol.
Test for terpenoids
A total of 1 mL of chloroform, acetic anhydride, and undiluted sulphuric acid were sequentially added to 1 mL of the Agave leaf extract. The presence of terpenoids was established by the observation of a reddish-violet hue in the mixture.
Test for saponins
A total of 3 mL of distilled water and five drops of olive oil were added to 1 mL of Agave plant extract and shaken vigorously for 2 min. The solution produced a persistent foam, which indicated the presence of saponins.
Test for steroids
A total of 2 mL of acetic anhydride was added to 1 mL of Agave leaf chloroform extract followed by the addition of undiluted sulphuric acid. The appearance of green colouration indicated the presence of steroids.
Test for glycosides
Salkowski’s test: The presence of steroidal aglycone (a glycoside component) was indicated by the brownish-red colour when 2 mL of concentrated sulphuric acid was combined with 5 mL of the Agave extract.
Test for alkaloid (Wagner’s test)
A few drops of Wagner’s reagent were added to 2 mL of Agave extract and 1.5% hydrochloric acid. The formation of a brownish precipitate demonstrated the presence of alkaloids.
2,2-diphenyl-1-picryl-hydrazyl-hydrate test for evaluating antioxidant activity
The Agave extract samples were reconstituted in dimethyl sulphate (DMSO) to yield a final concentration of 100 mg/mL. Sonication was used for the samples with solubility challenges, and the extracts were kept at 4 oC after being sonicated. The prepared DPPH (120 µL, made by dissolving 0.1 mM in ethanol) and 120 µL of Tris-HCl buffer (50 mM, pH 7.4) were put into a 96-well plate containing a five-microliter sample. The plate was then incubated in the dark for 20 min at room temperature. Using a BioTek® PowerWave XS spectrophotometer (Winooski, VT, USA), the absorbance was measured at 513 nm, and the % radical scavenging equation was computed as follows:

The buffer was swapped for the 5 µL sample that served as the control. Two final concentrations of 250 µg/mL and 500 µg/mL of plant extracts were tested.
Ferric reducing or antioxidant power test for evaluating antioxidant activity
The FRAP method was used to evaluate the possible antioxidant activity of the Agave extracts. The following adjustments were made to the procedure that was published by Benzie and Strain (1996) to measure the ferric-reducing ability of the extracts and antioxidant controls. Dimethyl sulphate was used to generate stock solutions of the compounds (100 mg/mL) and the positive control, trolox (10 mM). Twenty millilitres of sodium acetate buffer (300 mM), 2 mL of freshly prepared TPTZ solution (10 mM TPTZ and 40 mM HCl dissolved at 50 ºC in a water bath), 2 mL of freshly prepared FeCl3 solution (20 mM ferric chloride in distilled water), and 2 mL of distilled water comprised the FRAP reagent. A 96-well plate containing 50 µL of the samples and 200 µL of FRAP reagent was incubated for 30 min at 37 °C. Using a BioTek® PowerWave XS spectrophotometer (Winooski, VT, USA), the absorbance was measured at 593 nm. The results were expressed as (Fe2SO4 [µmol/L]/mg sample), which was calculated using a ferrous sulphate (Fe2SO4) (1.25 µmol/L – 200 µmol/L) standard curve.
Ethical considerations
This study followed all ethical standards for research without direct contact with human or animal subjects.
Results
Phytochemical evaluation
The results from the phytochemical screening of the Agave plant leaves, presented in Table 1, showed that both Agave species leaf extracts contained phytoconstituents with therapeutic benefits.
TABLE 1: Phytochemical screening of Agave angustifolia (AA) and Agave sisalana (AS) leaf extracts. |
The qualitative analysis of A. angustifolia revealed that the plant contained terpenes or terpenoids, aglycones (a steroidal portion of glycosides), flavonoids, phenols, and saponins, while steroids and alkaloids were not detected in the extracts. The A. angustifolia hexane extract showed a strong content of terpenoids and a weak presence of flavonoids, tannins, phenolic compounds, saponins, and glycosides, while steroid and alkaloid compounds were not detected. A moderate content of flavonoid compounds was observed in the A. angustifolia ethyl acetate extract, while saponin and glycoside compounds were weakly present, and the compounds of tannins, phenolics, terpenoids, steroids, and alkaloids were not detected. The A. angustifolia methanolic extract revealed a strong presence of flavonoids, moderate saponins, and a weak availability of tannins, terpenoids, and glycosides, while phenolics steroids, and alkaloids were not detected. The hexane extract of A. sisalana indicated moderate content of tannins, phenolics, and steroids, and a faint presence of flavonoids, terpenoids, saponins and glycosides, but alkaloid compounds were not detected. On the other hand, AS ethyl acetate extract showed a high presence of flavonoid and alkaloids, while phenolics were moderately present, and tannins, saponins and glycosides were slightly detected. Flavonoids and alkaloids were strongly detected in the AS methanolic extract, while saponins were moderately detected. Phenolics, glycosides and terpenoids were slightly present, and tannins and steroids were not detected in the methanolic extract of A. sisalana.
Alkaloids and terpenoids are known to protect plants from entrants and herbivores as well as to repel pathogens (López-Romero et al. 2018) and the saponins have antimicrobial and anti-inflammatory qualities (Yu et al. 2022). The methanol extract of A. angustifolia, ethyl acetate and methanol extracts of A. sisalana are laden with flavonoids, which characteristically are high in antioxidant concentrations that neutralise reactive oxidative stresses caused by ultraviolet B (UVB) rays and preserve the integrity of overall skin quality and appearance. The UVB radiations destroy filaggrin, which maintains the protective functions of skin barriers. Studies have established that plant extracts loaded with flavonoids and alkaloids protect the skin from UVB radiation damage (Chen et al. 2022). The hexane extract of A. angustifolia contained a high amount of terpenoids, which are known to demonstrate good antimicrobial, anti-allergic, and anti-inflammatory activities (Masyita et al. 2022). The availability of these phytochemicals in the Agave plants indicates the potential use of the plant extracts for antimicrobial, anti-fungal and anti-inflammatory properties.
The findings from this study agreed with a study by Hernandez-Valle et al. (2014), which established the extraction of steroidal saponins from A. angustifolia leaves.
Stępniowska et al. (2021) reported that alkaloids are used in cosmetics as antioxidants, skin-lightening or even-tone agents, antimicrobials, anti-cellulite, anti-ageing, calming, and anti-inflammatory substances. This suggests that the ethyl acetate and the methanol extracts from A. sisalana have a potential for use in cosmetic products claiming antimicrobial, anti-cellulite, anti-ageing, calming, and anti-inflammatory gentle soothing properties.
According to Kumar et al. (2020), plant phenolics offer protection against environmental stressors such as UV radiation, pathogenic infections, and predators. This indicates the potential use of A. sisalana in cosmetic products claiming UV protection. Goge et al. (2023) reported that tannins have therapeutic benefits because they facilitate the quick healing of wounds, and plants with high tannin content have strong antibacterial properties.
The antioxidant activity
The antioxidant activity of the Agave leaves (Figure 2) represented the antioxidant activity of the six Agave extracts (hexane, ethyl acetate and methanol extract from A. angustifolia and A. sisalana), with the DPPH assay reported as a percentage of DPPH scavenged. Trolox served as a favourable reference point. The error bars show the standard deviation of quadruplicate values obtained in a single experiment. The A. angustifolia exhibited negligible DPPH activity in the methanol extract, but more than 50% DPPH scavenging activity in the hexane and ethyl acetate extracts. These results suggest that A. angustifolia possesses non-polar and slightly polar antioxidant compounds. At the maximum treatment concentrations, the ethyl acetate and methanol extracts of A. sisalana demonstrated more than 50% DPPH scavenging activity, while the hexane extract exhibited negligible DPPH activity. These results indicated that only polar antioxidant phytochemicals were detected in the A. sisalana plant. The ethyl acetate solvent extracted the antioxidant phytocompounds from both Agave plants. Determining the antioxidant activity using the FRAP method (Figure 3) indicated that all plant extracts demonstrated minimal antioxidant activity at the highest treatment concentration. Both plants had more activity in the methanol extract, with the lowest activity demonstrated by the hexane extract, which had higher values in A. angustifolia than in A. sisalana. The ethyl acetate extract showed higher activity for A. sisalana than for A. angustifolia. All the outcomes were noticed at the highest treatment concentration of 2 mg/mL. Although the DPPH method claimed more potent antioxidant activity, the results from the FRAP and DPPH methods showed a similar trend. These results corresponded with Munteanu and Apetrei (2021), who wrote that, although the kinetics and stages of the reactions differ, the single electron transfer (FRAP) and hydrogen atom transfer (DPPH) reactions produce identical outcomes because they are dependent on the solvent system, the antioxidant compound’s solubility, and its structure and characteristics. These findings are consistent with Araldi’s work (Araldi et al. 2018), which found that A. sisalana exhibited antioxidant activity. When comparing the two methods, the DPPH is the recommended approach for the antioxidant assay of the Agave plants.
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FIGURE 2: The 2,2-diphenyl-1-picryl-hydrazyl-hydrate assay of Agave leaves’ extracts, a & d = Hexane; b & e = Ethyl Acetate; c & f = Methanol. |
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FIGURE 3: The ferric reducing or antioxidant power assay of Agave leaves’ extracts, a & d = Hexane; b & e = Ethyl Acetate; c & f = Methanol. |
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Conclusion
This study aimed firstly to assess the phytochemical profiles and antioxidant activities of A. angustifolia and A. sisalana plants in KZN and secondly to verify the traditional therapeutic claims of the Agave species and, accordingly, establish the assertions of the cottage industries. The qualitative phytochemical assessment established that both the A. angustifolia and A. sisalana leaf extracts contained six phytoconstituents: flavonoids, glycosides, phenolic acids, saponins, tannins and terpenes or terpenoids. However, the A. sisalana has two more phytochemical classes: alkaloids and steroids.
Both Agave plants showed potential to be used in cosmetic preparations, claiming antioxidant, anti-ageing, moisturising, UV protection, emulsifying, anti-inflammatory, astringent, antiseptic, anti-tumour, and antimicrobial activities. Thus, confirming the traditional therapeutic claims of the Agave species as asserted by the participants of the cottage industries. Further studies are required to determine the best environmentally friendly solvent for the plants’ extraction, categorise the specific antioxidant compounds, and conduct antimicrobial and cytotoxic studies to confirm the safety of the extracts for use in the production of cosmetic products, as required by legislation (CTFA 2023).
Acknowledgements
The authors would like to thank the Mangosuthu University of Technology, Technology Station in Chemicals (MUT-TSC) and the Central University of Technology (CUT), Faculty of Health, and Environmental Sciences, Free State, for funding this study. Ms Samukelisiwe A. Sibiya is highly appreciated for her assistance in the study.
Competing interests
The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.
Authors’ contributions
N.G.M. carried out the research work and wrote the first draft of the article. M.C.A., I.T.M. and S.M.N. supervised and made all the necessary contributions to the study’s success. X.V.N. contributed to the design of the study and revision of the draft article. All authors read and approved the final article submission.
Funding information
The Mangosuthu University of Technology, Technology Station in Chemicals, Umlazi, Durban, and the Central University of Technology, Free State, provided funding for this study.
Data availability
The authors declare that the information contained in the article supports the study’s conclusions.
Disclaimer
The views and opinions expressed in this article are those of the authors and are the product of professional research. It does not necessarily reflect the official policy or position of any affiliated institution, funder, agency, or that of the publisher. The authors are responsible for this article’s results, findings, and content.
References
Ahumada-Santos, Y.P., Montes-Avila, J., Uribe-Beltrán, M.J., Díaz-Camacho, S.P., López-Angulo, G., Vega-Aviña, R. et al., 2013, ‘Chemical characterization, antioxidant and antibacterial activities of six Agave species from Sinaloa, Mexico’, Industrial Crops and Products 49, 143–149. https://doi.org/10.1016/j.indcrop.2013.04.050
Almazán-Morales, A., Moreno-Godínez, M.E., Hernández-Castro, E., Vázquez-Villamar, M., Mora-Aguilera, J.A., Cabrera-Huerta, E. et al., 2022, ‘Phytochemical profile and in vitro activity of Agave angustifolia and A. cupreata extracts against phytopathogenic fungi’, Opatología 40(2), 169–187. https://doi.org/10.18781/R.MEX.FIT.2202-6
Araldi, R.P., Dos Santos, M.O., Barbon, F.F., Manjerona, B.A., Meirelles, B.R., De Oliva Neto, P. et al., 2018, ‘Analysis of antioxidant, cytotoxic and mutagenic potential of Agave sisalana Perrine extracts using Vero cells, human lymphocytes and mice polychromatic erythrocytes’, Biomedicine & Pharmacotherapy 98, 873–885. https://doi.org/10.1016/j.biopha.2018.01.022
Benzie, I.F.F. & Strain, J.J., 1996, ‘The Ferric Reducing Ability of Plasma (FRAP) as a measure of “Antioxidant Power”: The FRAP assay’, Analytical Biochemistry 239(1), 70–76. https://doi.org/10.1006/abio.1996.0292
Bhattacharyya, A., Chattopadhyay, R., Mitra, S. & Crowe, S.E., 2014, ‘Oxidative stress: An essential factor in the pathogenesis of gastrointestinal mucosal diseases’, Physiological Reviews 94(2), 329–354. https://doi.org/10.1152/physrev.00040.2012
Briguglio, G., Costa, C., Pollicino, M., Giambò, F., Catania, S. & Fenga, C., 2020, ‘Polyphenols in cancer prevention: New insights (Review)’, International Journal of Functional Nutrition, Spandidos Publications 1(2), 1–11. https://doi.org/10.3892/ijfn.2020.9
Chen, Y.-F., Zhang, D.-D., Hu, D.-B., Li, X.-N., Luo, J.-F., Duan, X.-Y. et al., 2022, ‘Alkaloids and flavonoids exert protective effects against UVB-induced damage in a 3D skin model using human keratinocytes’, Results in Chemistry 4, 1–8. https://doi.org/10.1016/j.rechem.2022.100298
Chigodi, M., Samoei, D., Mutemi, M., Chigodi, M.O., Samoei, D.K. & Muthangya, M., 2013, ‘Phytochemical screening of Agave Sisalana Perrine leaves (waste)’, International Journal of Applied Biology and Pharmaceutical Technology 4(4), 200–204.
Cruz-Magalhães, V., Pereira Andrade, J., Freitas Figueiredo, Y., Arthur Santos Marbach, P. & Teodoro de Souza, J., 2020, ‘Sisal Bole Rot: An important but neglected disease’, Plant Diseases – Current Threats and Management Trends, 879. https://doi.org/10.5772/intechopen.86983
CTFA, 2023, ‘Bridging the gap 2023’, Cosmetic Compendium, July 2023, 1–407.
Dharajiya, D., Pagi, N., Jasani, H. & Patel, P., 2017, ‘Antimicrobial activity and phytochemical screening of Aloe vera (Aloe barbadensis Miller)’, International Journal of Current Microbiology and Applied Sciences 6(3), 2152–2162. https://doi.org/10.20546/ijcmas.2017.603.246
Franck, A.R., 2012, ‘Guide to Agave, Cinnamomum, Corymbia, Eucalyptus, Pandanus, and Sansevieria in the flora of Florida’, Phytoneuron 102, 1–23.
García-Mendoza, A. & Chiang, F., 2003, ‘The confusion of Agave Vivipara L. and A. Angustifolia Haw.’, Two Distinct Taxa 55, 82–87. https://doi.org/10.1663/0007-196X(2003)055[0082:TCOAVL]2.0.CO;2
Goge, S., Singh, K., Komoreng, L.V. & Coopoosamy, R.M., 2023, ‘Phytochemical profile of Aloe ferox Mill. across different regions within South Africa’, Journal of Medicinal Plants for Economic Development 7(1), 1–6. https://doi.org/10.4102/jomped.v7i1.178
Guimarães de Oliveira, LH, Alexandria Paiva Silva de Sousa, P, Felipe Hilario, F, Joventino Nascimento, G., Morais, J.P.S., Paulo de Medeiros, E. et al., 2016, ‘Agave sisalana extract induces cell death in Aedes aegypti hemocytes increasing nitric oxide production’, Asian Pacific Journal of Tropical Biomedicine, Hainan Medical University 6(5), 396–399. https://doi.org/10.1016/j.apjtb.2015.12.018
Hernández-Valle, E., Herrera-Ruiz, M., Salgado, G., Zamilpa, A., Ocampo, M., Aparicio, A. et al., 2014, ‘Anti-Inflammatory Effect of 3-O-[(6’-O-Palmitoyl)-β-D-glucopyranosyl Sitosterol] from Agave angustifolia on Ear Edema in Mice’, Molecules, 19(10), 15624–15637. https://doi.org/10.3390/molecules191015624
Jiménez-Ferrer, E., Vargas-Villa, G., Martínez-Hernández, G.B., González-Cortazar, M., Zamilpa, A., García-Aguilar, M.P. et al., 2022, ‘Fatty-acid-rich Agave angustifolia Fraction shows antiarthritic and immunomodulatory effect’, Molecules 27(21). https://doi.org/10.3390/molecules27217204
Kumar, S., Abedin, M.M., Singh, A.K. & Das, S., 2020, ‘Role of phenolic compounds in plant-defensive mechanisms’, Plant phenolics in sustainable agriculture, vol. 1, pp. 517–532. Springer, Singapore.
López-Romero, J.C., Ayala-Zavala, J.F., Peña-Ramos, E.A., Hernández, J. & González-Ríos, H., 2018, ‘Antioxidant and antimicrobial activity of Agave angustifolia extract on overall quality and shelf life of pork patties stored under refrigeration’, Journal of Food Science and Technology 55(11), 4413–4423. https://doi.org/10.1007/s13197-018-3351-3
Masyita, A., Sari, R.M., Astuti, A.D., Yasir, B., Rumata, N.R., Emran, T.B. et al., 2022, ‘Terpenes and terpenoids as main bioactive compounds of essential oils, their roles in human health and potential application as natural food preservatives’, Food Chemistry: X 13, 100217. https://doi.org/10.1016/j.fochx.2022.100217
Michalak, M., 2022, ‘Plant-derived antioxidants: Significance in skin health and the Ageing process’, International Journal of Molecular Sciences 23(2), 585. https://doi.org/10.3390/ijms23020585
Mina, S.A., Melek, F.R., Abdel-Khalik, S.M. & Gabr, N.M., 2013, Two steroidal saponins from Agave Franzosinii and Agave Angustifolia leaves and biological activities of Agave Franzosinii’, Journal of Natural Products 6, 188–197.
Monterrosas-Brisson, N., Ocampo, M., Jiménez-Ferrer, E., Jiménez-Aparicio, A., Zamilpa, A., Gonzalez-Cortazar, M. et al., 2013, ‘Anti-inflammatory activity of different Agave plants and the compound cantalasaponin-1’, Molecules 18(7), 8136–8146. https://doi.org/10.3390/molecules18078136
Munteanu, I.G. & Apetrei, C., 2021, ‘Analytical methods used in determining antioxidant activity: A review’, International Journal of Molecular Sciences 22(7), 3380. https://doi.org/10.3390/ijms22073380
Rivera-Lugo, M., García-Mendoza, A., Simpson, J., Solano, E. & Gil-Vega, K., 2018, ‘Taxonomic implications of the morphological and genetic variation of cultivated and domesticated populations of the Agave angustifolia complex (Agavoideae, Asparagaceae) in Oaxaca, Mexico’, Plant Systematics and Evolution, Springer-Verlag Wien 304(8), 969–979. https://doi.org/10.1007/s00606-018-1525-0
Roy, A., Khan, A., Ahmad, I., Alghamdi, S., Rajab, B.S., Babalghith, A.O. et al., 2022, ‘Flavonoids a bioactive compound from medicinal plants and its therapeutic applications’, BioMed Research International 2022, 1–9. https://doi.org/10.1155/2022/5445291
Salazar-Pi, D.T., Castro-Ala, N., Moreno-God, M.E., Nicasio-To, M.P., Perez-Hern, J. & Alvarez-Fi, P., 2017, ‘Antibacterial and anti-inflammatory activity of extracts and fractions from Agave cupreata’, International Journal of Pharmacology 13(8), 1063–1070. https://doi.org/10.3923/ijp.2017.1063.1070
Stępniowska, A., Cieplińska, P., Fac, W. & Gorska, J., 2021, ‘Selected Alkaloids Used in the Cosmetics Industry’, Journal of Cosmetic Science 72(2), 229–245.
Velázquez-Martínez, J.R., González-Cervantes, R.M., Hernández-Gallegos, M.A., Mendiola, R.C., Aparicio, A.R.J. & Ocampo, M.L.A., 2014, ‘Prebiotic potential of Agave angustifolia haw fructans with different degrees of polymerization’, Molecules 19(8), 12660–12675. https://doi.org/10.3390/molecules190812660
Vera-Guzmán, A., Guzmán-Gerónimo, R., López, M. & Chávez-Servia, J., 2018, ‘Volatile compound profiles in mezcal spirits as influenced by Agave species and production processes’, Beverages 4(1), 9. https://doi.org/10.3390/beverages4010009
Verloove, F. & Pascual, M.S., 2021, ‘Notes on genuine Agave vivipara (Agavaceae), a poorly known Caribbean species, recently introduced in the Canary Islands (Spain)’, Bradleya 2021(39), 259–264. https://doi.org/10.25223/brad.n39.2021.a28
Verloove, F., Thiede, J., Rodríguez, Á.M., Salas-Pascual, M., Reyes-Betancort, J.A., Ojeda-Land, E. et al., 2019, ‘A synopsis of feral agave and furcraea (Agavaceae, asparagaceae s. lat.) in the Canary Islands (Spain)’, Plant Ecology and Evolution, Societe Royale de Botanique de Belgique 152(3), 470–498. https://doi.org/10.5091/plecevo.2019.1634
Villanueva-Rodríguez, S.J., Rodríguez-Garay, B., Prado-Ramírez, R. & Gschaedler, A., 2016, ‘Tequila: Raw material, classification, process, and quality parameters’, Encyclopedia of Food and Health 283–289. https://doi.org/10.1016/B978-0-12-384947-2.00688-7
Wu, S., Pang, Y., He, Y., Zhang, X., Peng, L., Guo, J. et al., 2021, ‘A comprehensive review of natural products against atopic dermatitis: Flavonoids, alkaloids, terpenes, glycosides and other compounds’, Biomedicine and Pharmacotherapy 140, 111741. https://doi.org/10.1016/j.biopha.2021.111741
Xiao, J. & Bai, W., 2019, ‘Bioactive phytochemicals’, Critical Reviews in Food Science and Nutrition 59(1), 827–829. https://doi.org/10.1080/10408398.2019.1601848
Yu, B., Patterson, N. & Zaharia, L.I., 2022, ‘Saponin biosynthesis in pulses’, Plants 11(24), 3505. https://doi.org/10.3390/plants11243505
Zwane, P.E., Dlamini, A.M. & Nkambule, N., 2010, ‘Antimicrobial properties of Sisal (Agave sisalana) used as an ingredient in petroleum jelly production in Swaziland’, Current Research Journal of Biological Sciences 2(6), 370–374.
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