1. Introduction
Yucca L., a perennial evergreen shrub belonging to the Agavaceae family, is native to North and Central America and is now widely cultivated in tropical and subtropical regions worldwide.
Its roots, stems, leaves, and flowers have been used in traditional medicine for over a thousand years to treat arthritis, skin ulcers, gastrointestinal inflammation, diabetes, and other diseases.
With the development of natural product chemistry and modern pharmacology, yucca extract has become a research hotspot at home and abroad due to its rich active components (such as saponins, polysaccharides, and polyphenols) and various biological activities (antioxidant, anti-inflammatory, and gut health regulation).
This article systematically reviews the chemical composition, biological activities, and Research progress on Yucca Extract.
2. Chemical Composition
The active components of yucca extract mainly include saponins, polysaccharides, polyphenols, and sterols, among which saponins are the core active components. The detailed information of each component is shown in the following table:
| Component Type | Main Sources in Yucca | Key Components/Structural Characteristics | Content (Dry Weight) | Key Properties |
| Saponins | Roots, Stems | Triterpenoid saponins; aglycones mainly yuccagenin; sugar chains composed of glucose, galactose, rhamnose, etc. | 2%~5% | Strong surface activity (minimum surface tension of 28 mN/m); stable under acidic conditions; resistant to high temperatures |
| Polysaccharides | Leaves | Composed of arabinose, xylose, glucose, etc.; molecular weight of 10~50 kDa | Not specified | Highly branched polysaccharides (>30% branching degree) have stronger immunomodulatory effects; linear polysaccharides are more easily fermented by gut microbiota |
| Polyphenols | Leaves, Flowers | Chlorogenic acid, quercetin, kaempferol (with phenolic hydroxyl groups) | 0.5%~1.2% | Phenolic hydroxyl groups are the main source of antioxidant activity |
| Sterols | Seeds | Mainly β-sitosterol and stigmasterol | 0.1%~0.3% | Have hypolipidemic and anti-inflammatory effects |
3. Biological Activities
3.1 Antioxidant Activity
The antioxidant activity of yucca extract mainly comes from polyphenols and saponins. Wang et al. (2020) evaluated the antioxidant capacity of yucca leaf extract using DPPH free radical scavenging assay, FRAP total antioxidant capacity assay, and ABTS+ free radical scavenging assay. The results showed that at a concentration of 1 mg/mL, the DPPH scavenging rate reached 85.2%, the FRAP value was 12.6 mmol Fe²⁺/g, and the ABTS+ scavenging rate was 91.3%, all significantly higher than those of vitamin C at the same concentration (P<0.05). Further studies found that chlorogenic acid inhibits lipid peroxidation by chelating metal ions (such as Fe³⁺ and Cu²⁺), while quercetin scavenges free radicals by donating hydrogen atoms.
3.2 Anti-inflammatory Activity
The anti-inflammatory mechanism of yucca extract is mainly related to inhibiting the NF-κB signaling pathway and reducing the secretion of inflammatory factors. Li et al. (2019) used LPS-induced RAW264.7 macrophages as a model and found that 50 μg/mL yucca root extract significantly inhibited the secretion of NO, TNF-α, and IL-6, with inhibition rates of 78.5%, 65.3%, and 59.8%, respectively. In addition, yucca saponins reduce the synthesis of prostaglandin E₂ (PGE₂) by lowering the expression of cyclooxygenase-2 (COX-2), thereby alleviating inflammatory responses.
3.3 Antimicrobial Activity
Yucca extract has inhibitory effects on both Gram-positive bacteria (such as Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (such as Escherichia coli and Salmonella), with the strongest inhibitory effect on Staphylococcus aureus (MIC=0.25 mg/mL). Zhang et al. (2021) found that yucca saponins disrupt the integrity of bacterial cell membranes, leading to the leakage of intracellular nucleic acids and proteins, thereby exerting antimicrobial effects. In addition, polyphenols inhibit bacterial respiration and enzyme activity, enhancing the antimicrobial effect.
3.4 Regulation of Gut Health
The regulatory effect of yucca extract on gut health is mainly reflected in improving intestinal morphology, regulating gut microbiota balance, and reducing ammonia emission. Liu et al. (2020) added 0.1% yucca extract to broiler feed and found that the villus height of broiler intestines increased by 21.3%, the crypt depth decreased by 18.5%, and the intestinal absorption area expanded significantly. At the same time, the number of Bifidobacterium increased by 45.6%, the number of Escherichia coli decreased by 32.8%, and the diversity of gut microbiota improved. In addition, yucca saponins bind to ammonia in the intestine to form stable complexes, reducing ammonia concentration in feces (reduction rate of 50%~70%) and improving the breeding environment.
3.5 Hypolipidemic and Hypoglycemic Activities
The hypolipidemic effect of yucca extract is mainly related to inhibiting cholesterol absorption and promoting bile acid excretion. Chen et al. (2022) used hyperlipidemic rats as a model and found that after 4 weeks of gavage with 100 mg/kg·d yucca extract, the levels of serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) decreased by 28.6%, 31.2%, and 35.7%, respectively, while the level of high-density lipoprotein cholesterol (HDL-C) increased by 22.4%. The mechanism is that yucca saponins bind to cholesterol in the intestine to reduce its absorption; at the same time, they promote the synthesis and excretion of bile acids in the liver, increasing cholesterol metabolism.
In terms of hypoglycemic activity, Wang et al. (2023) found that yucca polysaccharides can increase the activity of glucokinase (GK) in the liver of diabetic mice, promoting the conversion of glucose to liver glycogen; at the same time, they inhibit the activity of α-glucosidase, delaying the digestion and absorption of carbohydrates, thereby reducing postprandial blood glucose (reduction rate of 25.8%).
3.6 Antitumor Activity
The antitumor activity of yucca extract mainly comes from inducing cancer cell apoptosis and inhibiting tumor angiogenesis. Zhang et al. (2024) used human hepatoma cells HepG2 as a model and found that 100 μg/mL yucca saponins can induce cancer cell apoptosis (apoptosis rate of 42.5%) by activating the caspase-3/9 pathway; at the same time, they inhibit the expression of vascular endothelial growth factor (VEGF) and reduce tumor angiogenesis (inhibition rate of 58.3%). In addition, polyphenols scavenge free radicals in cancer cells and inhibit their proliferation (proliferation inhibition rate of 36.7%).
Summary of Key Biological Activities and Experimental Results
| Biological Activity | Research Model | Dosage/Concentration | Key Results | Researcher (Year) |
| Antioxidant | Yucca leaf extract in vitro | 1 mg/mL | DPPH scavenging rate 85.2%, FRAP value 12.6 mmol Fe²⁺/g, ABTS+ scavenging rate 91.3% (all higher than vitamin C at the same concentration, P<0.05) | Wang et al. (2020) |
| Anti-inflammatory | LPS-induced RAW264.7 macrophages | 50 μg/mL (yucca root extract) | Inhibition rates of NO, TNF-α, IL-6: 78.5%, 65.3%, 59.8% respectively | Li et al. (2019) |
| Antimicrobial | Staphylococcus aureus, Escherichia coli, etc. | MIC=0.25 mg/mL (for Staphylococcus aureus) | Disrupts bacterial cell membrane integrity; inhibits bacterial respiration and enzyme activity | Zhang et al. (2021) |
| Regulation of Gut Health | Broilers | 0.1% in feed | Intestinal villus height +21.3%, crypt depth -18.5%; Bifidobacterium +45.6%, Escherichia coli -32.8%; fecal ammonia reduction rate 50%~70% | Liu et al. (2020) |
| Hypolipidemic | Hyperlipidemic rats | 100 mg/kg·d (gavage, 4 weeks) | TC -28.6%, TG -31.2%, LDL-C -35.7%, HDL-C +22.4% | Chen et al. (2022) |
| Hypoglycemic | Diabetic mice | Not specified (yucca polysaccharides) | Postprandial blood glucose reduction rate 25.8% | Wang et al. (2023) |
| Antitumor | Human hepatoma cells HepG2 | 100 μg/mL (yucca saponins) | Cancer cell apoptosis rate 42.5%; tumor angiogenesis inhibition rate 58.3%; proliferation inhibition rate 36.7% | Zhang et al. (2024) |
4. Application Research
Yucca extract has been widely researched and applied in the food industry, feed industry, cosmetics field, and pharmaceutical field due to its various biological activities. The specific application situations are shown below:
| Application Field | Main Application Purposes | Application Cases & Results | Researcher (Year) |
| Food Industry | Preservation, emulsification, flavor improvement | 1. Adding 0.3% yucca extract to bread: inhibits Aspergillus niger growth, extends shelf life from 3 days to 5 days, no significant change in taste and flavor; 2. Used as emulsifier in ice cream: expansion rate increased by 15%, taste improved | Li et al. (2021) |
| Feed Industry | Replacing antibiotics, promoting growth, improving breeding environment | Adding 0.05% yucca extract to piglet feed (replacing antibiotics): average daily gain +12.5%, feed conversion ratio -8.3%, diarrhea rate from 15% to 5% | Zhao et al. (2020) |
| Cosmetics Field | Antioxidant, moisturizing, anti-inflammatory | Adding 1% yucca extract to face cream (human trial, 4 weeks): facial wrinkle depth -18.7%, skin moisture content +25.6%, inflammatory reactions (redness, swelling) -30.2% | Wang et al. (2023) |
| Pharmaceutical Field | Anti-inflammatory drugs, gut health products | 1. Anti-inflammatory capsules (e.g., “Yucca Plus”) for arthritis and gastrointestinal inflammation: clinical effective rate 70%~80%; 2. Yucca polysaccharides added to probiotic products as prebiotics to improve gut microbiota balance | Not specified |
5. Conclusion and Prospects
Yucca extract, as a natural product, has rich biological activities and broad application prospects. At present, its research mainly focuses on chemical composition and animal experiments, with relatively few clinical studies, and the mechanism of action of some active components is still unclear (such as the specific regulatory mechanism of polysaccharides on gut microbiota). In the future, the following aspects should be strengthened:
- Separation and structural identification of active components to clarify their structure-activity relationship;
- Conduct large-scale clinical studies to verify their safety and effectiveness;
- Develop new formulations (such as nanoparticles and liposomes) to improve their bioavailability;
- Expand their applications in medicine, cosmetics, and other fields to achieve industrialization.