Strategies for Selecting and Preparing Plant Extracts for Antioxidant Studies

1. Significance of Hydroxyl Radicals in Biology

1. Significance of Hydroxyl Radicals in Biology

Hydroxyl radicals (·OH) are among the most reactive and short-lived of all known reactive oxygen species (ROS). They play a significant role in various biological processes, both beneficial and detrimental. Understanding their role is crucial for assessing the impact of plant extracts in antioxidant research.

1.1 The Dual Role of Hydroxyl Radicals
Hydroxyl radicals are produced endogenously as a byproduct of normal cellular metabolism, particularly during the respiratory burst in immune cells and the detoxification process in the liver. They are also generated exogenously through exposure to ionizing radiation, environmental pollutants, and certain chemicals. While they are essential for certain biological functions, such as the destruction of invading pathogens, they can also cause significant damage to cellular components if not properly regulated.

1.2 Damage Caused by Hydroxyl Radicals
The high reactivity of hydroxyl radicals means they can readily react with a wide range of biological molecules, including lipids, proteins, and nucleic acids. This can lead to lipid peroxidation, protein denaturation, and DNA damage, which are all implicated in the development of various diseases and the aging process. The oxidative stress resulting from an imbalance between the production of ROS and the ability of the body to detoxify them or repair the resulting damage is considered a major factor in the pathogenesis of many chronic diseases, including cancer, cardiovascular diseases, and neurodegenerative disorders.

1.3 Antioxidant Defense Mechanisms
To counteract the harmful effects of hydroxyl radicals and other ROS, organisms have evolved a complex antioxidant defense system. This system includes enzymes such as superoxide dismutase, catalase, and glutathione peroxidase, as well as non-enzymatic antioxidants like glutathione, vitamins C and E, and various phytochemicals. These antioxidants neutralize ROS, preventing or repairing the damage they cause.

1.4 Importance of Hydroxyl Radical Scavenging Assays
Given the role of hydroxyl radicals in disease pathogenesis, assays that measure the ability of substances to scavenge these radicals are of great importance in the field of antioxidant research. Hydroxyl radical scavenging assays provide a means to evaluate the antioxidant potential of various compounds, including those found in plant extracts. These assays are instrumental in identifying novel sources of natural antioxidants that could be used in the development of therapeutic agents, functional foods, and other health-promoting products.

1.5 Contribution of Plant Extracts
Plant extracts have been a rich source of bioactive compounds with antioxidant properties. Many plants contain polyphenols, flavonoids, and other secondary metabolites that can effectively scavenge hydroxyl radicals and other ROS. The study of these plant-derived antioxidants is not only relevant to understanding their potential health benefits but also to exploring their use in agriculture and food preservation, where they can help maintain the quality and safety of food products by preventing oxidative spoilage.

In the following sections, we will delve into the specifics of using plant extracts in hydroxyl radical scavenging assays, from the selection and preparation of these extracts to the experimental design, data analysis, and the broader implications of these studies.

2. Overview of Plant Extracts in Antioxidant Research

2. Overview of Plant Extracts in Antioxidant Research

Plant extracts have garnered significant attention in the field of antioxidant research due to their rich diversity of bioactive compounds. These natural sources offer a wide array of phytochemicals, including phenolics, flavonoids, terpenoids, and alkaloids, which are known for their potential to combat oxidative stress and related diseases.

2.1 Importance of Antioxidants
Antioxidants are crucial in mitigating the harmful effects of reactive oxygen species (ROS), such as hydroxyl radicals, which are produced during normal cellular metabolism and can cause cellular damage if not neutralized. Overproduction of ROS can lead to oxidative stress, which is implicated in various pathological conditions, including cancer, cardiovascular diseases, and neurodegenerative disorders.

2.2 Phytochemicals in Plant Extracts
Plant extracts are a treasure trove of phytochemicals that possess antioxidant properties. These compounds can act as reducing agents, hydrogen donors, or metal chelators, thereby preventing the formation of ROS or scavenging them before they cause damage. The antioxidant capacity of plant extracts is often attributed to their phenolic content, which includes flavonoids, tannins, and phenolic acids.

2.3 Traditional Uses and Modern Research
Historically, various plant extracts have been used in traditional medicine for their healing properties. Modern research has validated these traditional uses by scientifically investigating the antioxidant and other health-promoting effects of these plants. The exploration of plant extracts for their antioxidant potential has led to the discovery of novel compounds and a deeper understanding of their mechanisms of action.

2.4 Challenges and Opportunities
While plant extracts offer a promising avenue for antioxidant research, there are challenges associated with their study. These include the complexity of plant matrices, which can contain hundreds of different compounds, and the need for standardized methods to assess antioxidant activity. Despite these challenges, the opportunities for discovering new antioxidants and understanding their role in health and disease are vast.

2.5 Future Perspectives
As the understanding of the role of antioxidants in health and disease continues to grow, so does the interest in plant extracts as a source of these beneficial compounds. Future research will likely focus on the isolation and characterization of novel antioxidant compounds from plant extracts, as well as the development of more efficient methods for their extraction and application in various fields, such as food preservation, pharmaceuticals, and cosmetics.

In summary, plant extracts are a valuable resource in antioxidant research, offering a diverse range of bioactive compounds with the potential to mitigate oxidative stress and contribute to overall health. The exploration of these natural sources is essential for discovering new antioxidants and expanding our knowledge of their therapeutic potential.

3. Methodology for Hydroxyl Radical Scavenging Assay

3. Methodology for Hydroxyl Radical Scavenging Assay

The hydroxyl radical scavenging assay is a critical method used to evaluate the antioxidant capacity of plant extracts. This assay is based on the ability of antioxidants to neutralize the highly reactive hydroxyl radicals, thereby preventing or reducing oxidative damage to biological systems. The methodology for the hydroxyl radical scavenging assay can be divided into several key steps:

3.1 Reagent Preparation
- Fenton Reaction Mixture: Prepare a Fenton reaction mixture containing Fe^2+ and H2O2, which will generate hydroxyl radicals in the presence of EDTA to stabilize the Fe^2+ ions.
- Colorimetric Indicator: Select a suitable colorimetric indicator, such as deoxyribose, which reacts with hydroxyl radicals to form a colored product that can be measured spectrophotometrically.

3.2 Plant Extract Preparation
- Extraction: Choose appropriate solvents (e.g., methanol, ethanol, or water) to extract bioactive compounds from the plant material.
- Concentration: Concentrate the extracts to a known concentration, ensuring consistency across samples.

3.3 Assay Setup
- Control Group: Prepare a control group containing all components except the plant extract to establish the baseline level of hydroxyl radical formation.
- Test Groups: Add varying concentrations of the plant extract to the Fenton reaction mixture to create a range of test groups.

3.4 Incubation
- Allow the reaction to proceed under controlled conditions (e.g., temperature, pH) for a specified time period to ensure adequate reaction between the hydroxyl radicals and the plant extract.

3.5 Color Development
- After incubation, initiate the color development by adding the colorimetric indicator. The reaction with hydroxyl radicals will produce a colored product.

3.6 Spectrophotometric Analysis
- Measure the absorbance of the colored product at a specific wavelength using a spectrophotometer. The decrease in absorbance is indicative of the hydroxyl radical scavenging activity of the plant extract.

3.7 Data Collection
- Record the absorbance values for each test group and the control group. Ensure that the measurements are taken under identical conditions to maintain consistency.

3.8 Calculation of Scavenging Activity
- Calculate the percentage of hydroxyl radical scavenging activity using the formula:
\[
\text{Scavenging Activity} (\%) = \left(1 - \frac{\text{Absorbance of Test Group}}{\text{Absorbance of Control Group}}\right) \times 100
\]

3.9 Standard Curve
- If applicable, prepare a standard curve using a known antioxidant (e.g., ascorbic acid) to quantify the antioxidant activity of the plant extract.

3.10 Statistical Analysis
- Perform statistical analysis to determine the significance of the results, including ANOVA or t-tests, as appropriate.

3.11 Reproducibility and Validation
- Ensure the assay is validated for accuracy, precision, and reproducibility by conducting replicate experiments and including positive and negative controls.

This methodology provides a systematic approach to evaluate the hydroxyl radical scavenging capacity of plant extracts, which is essential for understanding their potential as natural antioxidants in various applications.

4. Selection and Preparation of Plant Extracts

4. Selection and Preparation of Plant Extracts

The selection and preparation of plant extracts are crucial steps in conducting a hydroxyl radical scavenging assay. These processes ensure that the extracts are representative of the plant's antioxidant properties and are suitable for the assay. Here, we discuss the factors to consider when selecting plant extracts and the methods for their preparation.

4.1 Criteria for Plant Selection

When selecting plants for the hydroxyl radical scavenging assay, researchers should consider the following criteria:

- Botanical Diversity: A variety of plants from different botanical families can provide a broad spectrum of phytochemicals.
- Traditional Use: Plants with a history of traditional use in medicine or as food may have known antioxidant properties.
- Availability: The ease of obtaining the plant material is essential for practical research purposes.
- Ecological Considerations: The sustainability of the plant source and its ecological impact should be taken into account.

4.2 Collection of Plant Material

The plant material should be collected from healthy plants, preferably during their peak growth period to maximize the content of bioactive compounds. The collection should be done in a manner that does not harm the plant or its habitat.

4.3 Identification and Authentication

It is essential to accurately identify the plant species to ensure the reproducibility of the study. The use of a botanist or a taxonomist is recommended for plant identification. Voucher specimens should be deposited in a recognized herbarium for future reference.

4.4 Preparation of Plant Extracts

The preparation of plant extracts involves several steps, including:

- Cleaning: The plant material should be thoroughly cleaned to remove dirt and other contaminants.
- Drying: The plant material is air-dried or oven-dried at a temperature not exceeding 40°C to prevent the degradation of heat-sensitive compounds.
- Grinding: The dried plant material is ground into a fine powder using a mortar and pestle or a mechanical grinder.
- Extraction: The extraction method depends on the polarity of the compounds of interest. Common solvents used include water, ethanol, methanol, and dichloromethane. The choice of solvent can affect the yield and composition of the extract.

4.5 Solvent Selection

The choice of solvent is critical as it can influence the extraction efficiency and the type of compounds extracted. Polar solvents like water and methanol are suitable for hydrophilic compounds, while non-polar solvents like dichloromethane are better for lipophilic compounds.

4.6 Extraction Techniques

Different extraction techniques can be employed, such as:

- Soaking Method: The plant material is soaked in the solvent for a specific period.
- Decoction: The plant material is boiled in water or another solvent.
- Infusion: The plant material is steeped in hot solvent, similar to tea preparation.
- Ultrasonic-Assisted Extraction: This method uses ultrasonic waves to enhance the extraction process.
- Supercritical Fluid Extraction: This technique uses supercritical fluids, typically carbon dioxide, to extract compounds.

4.7 Concentration and Storage

The extracts are usually concentrated under reduced pressure using a rotary evaporator to remove the solvent and obtain a viscous liquid or a solid residue. The concentrated extracts should be stored in airtight containers, protected from light, and kept at low temperatures to prevent degradation.

4.8 Quality Control

It is essential to perform quality control checks on the extracts to ensure their consistency and to monitor the presence of contaminants. This can be done through chromatographic techniques, such as high-performance liquid chromatography (HPLC), or spectroscopic methods, such as ultraviolet-visible (UV-Vis) spectroscopy.

In conclusion, the selection and preparation of plant extracts are critical steps that require careful consideration of the plant species, extraction methods, and solvents used. These factors will ultimately influence the success of the hydroxyl radical scavenging assay and the reliability of the results obtained.

5. Experimental Design and Procedure

5. Experimental Design and Procedure

5.1 Objectives
The primary objective of the experimental design is to evaluate the hydroxyl radical scavenging capacity of various plant extracts. This will be achieved by comparing their ability to inhibit the formation of hydroxyl radicals in a controlled in vitro assay.

5.2 Selection of Plant Extracts
A diverse range of plant extracts will be selected based on their traditional use, availability, and potential antioxidant properties. These may include fruits, vegetables, herbs, and spices known to possess bioactive compounds with antioxidant capabilities.

5.3 Preparation of Plant Extracts
Each plant extract will be prepared by following a standardized extraction protocol. This typically involves:
- Weighing a specific amount of dried plant material.
- Soaking the plant material in a solvent, such as methanol or ethanol, to extract bioactive compounds.
- Filtering the solution to obtain a clear extract.
- Evaporating the solvent to obtain a concentrated extract, which will be reconstituted in a suitable solvent for the assay.

5.4 Standardization of Plant Extracts
To ensure consistency and reproducibility, the plant extracts will be standardized based on their total phenolic content or other relevant bioactive markers. This will allow for a direct comparison of their antioxidant activities.

5.5 Experimental Setup
The hydroxyl radical scavenging assay will be conducted using a reaction mixture containing:
- A source of hydroxyl radicals, such as the Fenton reaction system (Fe^2+ and H2O2).
- A probe molecule that reacts with hydroxyl radicals, such as deoxyribose or 2-deoxy-D-ribose.
- Plant extracts at varying concentrations to assess their dose-response relationship.

5.6 Assay Procedure
The assay will be performed as follows:
- Prepare a series of dilutions of each plant extract in the assay buffer.
- Mix the reaction components, including the plant extract, Fe^2+, H2O2, and probe molecule, in a microplate well.
- Incubate the reaction mixture at a specified temperature for a fixed duration to allow the reaction to proceed.
- Stop the reaction by adding a stopping solution, such as trichloroacetic acid (TCA) or another appropriate reagent.
- Measure the absorbance or fluorescence of the reaction mixture to quantify the extent of hydroxyl radical-induced damage to the probe molecule.

5.7 Controls and Standards
- Negative control: Reaction mixture without the plant extract to determine the baseline level of hydroxyl radical-induced damage.
- Positive control: Reaction mixture with a known antioxidant, such as ascorbic acid or trolox, to validate the assay conditions.
- Blank: Reaction mixture without the probe molecule to account for any background absorbance or fluorescence.

5.8 Data Collection
Record the absorbance or fluorescence readings for each sample and control using a microplate reader. Ensure that the assay is performed in triplicate or greater to ensure statistical reliability.

5.9 Quality Control Measures
- Perform the assay under standardized conditions, such as temperature and pH, to minimize variability.
- Use fresh reagents and maintain their stability throughout the experiment.
- Regularly calibrate the microplate reader to ensure accurate measurements.

By following this experimental design and procedure, a comprehensive assessment of the hydroxyl radical scavenging activity of various plant extracts can be achieved, providing valuable insights into their potential as natural antioxidants.

6. Data Analysis and Interpretation

6. Data Analysis and Interpretation

Data analysis and interpretation are pivotal steps following the completion of the hydroxyl radical scavenging assay using plant extracts. This section will outline the process of evaluating the experimental data and drawing meaningful conclusions from the results obtained.

6.1 Data Collection
After the hydroxyl radical scavenging assay is conducted, the absorbance values are recorded for each sample and control. These values are crucial as they represent the extent of the reaction between the hydroxyl radicals and the plant extracts.

6.2 Normalization of Data
To ensure a fair comparison among different plant extracts, the absorbance values are normalized. This is typically done by calculating the percentage of hydroxyl radical scavenging activity relative to a standard antioxidant, such as ascorbic acid or a known synthetic antioxidant.

6.3 Statistical Analysis
Statistical analysis is performed to determine the significance of the results. Commonly used tests include the Student's t-test for pairwise comparisons and ANOVA (Analysis of Variance) for multiple comparisons. These tests help to identify any statistically significant differences between the plant extracts and the control.

6.4 Graphical Representation
Data is often presented in graphical form for easier interpretation. Bar charts or line graphs can be used to compare the hydroxyl radical scavenging activity of different plant extracts. This visual representation aids in quickly identifying the most effective extracts.

6.5 Determination of IC50 Values
The IC50 value, which is the concentration of the plant extract required to scavenge 50% of the hydroxyl radicals, is calculated for each extract. Lower IC50 values indicate higher antioxidant activity. This parameter is useful for comparing the potency of different extracts.

6.6 Correlation with Total Phenolic Content
A correlation analysis may be performed between the hydroxyl radical scavenging activity and the total phenolic content of the plant extracts. This can provide insights into the relationship between phenolic compounds and antioxidant activity.

6.7 Interpretation of Results
The results are interpreted in the context of the study's objectives. High antioxidant activity in a plant extract suggests its potential use in various applications, such as in the food industry, pharmaceuticals, or cosmetics. The presence of specific bioactive compounds in the extract may also be inferred from the results.

6.8 Limitations and Assumptions
It is important to acknowledge any limitations in the study, such as the potential for other reactive species to interfere with the assay or the limitations of the assay itself. Assumptions made during the analysis, such as the linearity of the assay, should also be discussed.

6.9 Conclusions
Based on the data analysis and interpretation, conclusions are drawn regarding the antioxidant potential of the plant extracts. This may include identifying the most effective extracts, understanding the relationship between phenolic content and antioxidant activity, and suggesting potential applications.

6.10 Recommendations for Future Research
Finally, recommendations for future research are made based on the findings of the current study. This may involve further investigation into the specific bioactive compounds responsible for the antioxidant activity, testing additional plant extracts, or exploring the use of the identified extracts in different applications.

7. Comparison of Antioxidant Activity Among Plant Extracts

### 7. Comparison of Antioxidant Activity Among Plant Extracts

In the realm of natural products research, the quest for potent antioxidants has led to the exploration of various plant extracts. The hydroxyl radical scavenging assay serves as a crucial tool in comparing the antioxidant activity among these extracts. This section will delve into the comparative analysis of the antioxidant properties of different plant extracts, highlighting their potential as therapeutic agents and sources of natural antioxidants.

7.1 Methodological Considerations

The comparison of antioxidant activity begins with a standardized methodology for the hydroxyl radical scavenging assay. Ensuring that the assay conditions, such as pH, temperature, and reaction time, are consistent across all samples is essential for accurate and reliable comparisons. Additionally, the use of a control, typically a known antioxidant like ascorbic acid, provides a benchmark against which the plant extracts can be evaluated.

7.2 Variability in Plant Extracts

Plant extracts exhibit a wide range of antioxidant activities due to the diversity in their phytochemical compositions. Factors such as the plant species, part of the plant used (leaves, roots, fruits), extraction method, and solvent type can significantly influence the antioxidant capacity of the resulting extract. Therefore, a comprehensive comparison requires consideration of these variables.

7.3 Quantitative Analysis

The hydroxyl radical scavenging assay typically yields quantitative data, such as the IC50 value, which represents the concentration of the extract required to scavenge 50% of the hydroxyl radicals. Lower IC50 values indicate higher antioxidant activity. Comparative analysis can be performed by ranking the extracts based on their IC50 values or by calculating the relative antioxidant activity in comparison to a standard antioxidant.

7.4 Qualitative Assessment

Beyond quantitative measures, qualitative assessment of the antioxidant activity can provide insights into the specific compounds responsible for the observed effects. High-performance liquid chromatography (HPLC) and mass spectrometry can be employed to identify and quantify the bioactive compounds in the plant extracts, facilitating a more nuanced comparison of their antioxidant properties.

7.5 Correlation with Other Antioxidant Assays

The hydroxyl radical scavenging assay is just one of several methods used to evaluate antioxidant activity. Comparing the results from this assay with those from other assays, such as the DPPH radical scavenging assay or the ferric reducing antioxidant power (FRAP) assay, can offer a more holistic view of the antioxidant potential of the plant extracts.

7.6 Biological Relevance

The ultimate goal of comparing antioxidant activities among plant extracts is to identify those with the highest potential for use in food preservation, pharmaceuticals, or as dietary supplements. The relevance of the in vitro results to in vivo conditions must be considered, as the bioavailability and metabolism of the plant compounds can vary significantly in different biological contexts.

7.7 Conclusion

The comparison of antioxidant activity among plant extracts is a complex yet rewarding endeavor. By employing a rigorous and standardized methodology, researchers can identify novel sources of natural antioxidants and contribute to the development of healthier and more sustainable products. The insights gained from such comparisons can also inform future research directions, including the optimization of extraction methods, the identification of synergistic effects among compounds, and the exploration of new plant species for their antioxidant potential.

8. Potential Applications and Implications

8. Potential Applications and Implications

The potential applications and implications of hydroxyl radical scavenging assays using plant extracts are vast and multifaceted, reflecting the importance of antioxidants in various fields of research and industry. Here are some of the key areas where these findings can be applied:

1. Pharmaceutical Development: Plant extracts with high antioxidant activity can be used as a basis for developing new drugs to combat diseases associated with oxidative stress, such as neurodegenerative disorders, cardiovascular diseases, and cancer.

2. Functional Foods and Nutraceuticals: Incorporating plant extracts with proven hydroxyl radical scavenging properties into functional foods and nutraceuticals can enhance their health benefits, providing consumers with natural antioxidants to support overall health and well-being.

3. Cosmeceuticals: In the cosmetics industry, antioxidants from plant extracts can be used to develop products that protect the skin from environmental damage, reduce the signs of aging, and improve skin health.

4. Agricultural Practices: Understanding the antioxidant properties of various plant extracts can guide agricultural practices to cultivate plants with higher nutritional and health benefits, potentially improving crop quality and value.

5. Environmental Protection: Plant extracts with strong antioxidant capabilities can be used in environmental remediation efforts, helping to mitigate the effects of pollutants and toxins in the environment.

6. Food Preservation: The use of natural antioxidants from plant extracts can extend the shelf life of food products by preventing oxidation, which is a common cause of food spoilage.

7. Research and Education: The study of plant extracts for their antioxidant properties can serve as an educational tool to teach about the importance of antioxidants and the role of plants in human health.

8. Public Health Policies: Findings from hydroxyl radical scavenging assays can inform public health policies, advocating for the inclusion of more plant-based foods in diets to promote health and prevent disease.

9. Commercialization of Plant-Based Antioxidants: The commercial potential of plant extracts as natural antioxidants can lead to the development of new industries focused on the extraction, purification, and marketing of these beneficial compounds.

10. Ethnopharmacology: The study of traditional medicinal plants can be validated and expanded through scientific research on their antioxidant properties, potentially leading to the discovery of new therapeutic agents.

In conclusion, the implications of hydroxyl radical scavenging assays using plant extracts are far-reaching, offering opportunities for innovation in health, agriculture, and environmental protection, while also contributing to a deeper understanding of the therapeutic potential of nature's bounty.

9. Conclusion and Future Research Directions

9. Conclusion and Future Research Directions

In conclusion, the hydroxyl radical scavenging assay is a pivotal tool in assessing the antioxidant potential of plant extracts. The significance of hydroxyl radicals in biological systems cannot be overstated, as their reactivity and involvement in oxidative stress underscore the importance of identifying and utilizing natural antioxidants. Plant extracts have emerged as a rich source of bioactive compounds with diverse antioxidant properties, offering a promising avenue for research and application in various fields.

The methodology for the hydroxyl radical scavenging assay, as discussed, provides a standardized approach to evaluate the antioxidant capacity of plant extracts. The selection and preparation of these extracts are critical steps that influence the outcome of the assay, highlighting the need for careful consideration of plant species, extraction methods, and solvents.

The experimental design and procedure outlined in this article ensure a systematic approach to conducting the assay, while data analysis and interpretation provide insights into the antioxidant activity of the tested extracts. Comparing the antioxidant activity among different plant extracts allows for the identification of potential candidates with high scavenging potential, which can be further explored for their therapeutic and nutritional value.

The potential applications and implications of plant extracts with high antioxidant activity are vast, ranging from pharmaceutical and nutraceutical development to cosmetic and agricultural industries. These applications not only contribute to human health and well-being but also promote sustainable use of natural resources.

Looking ahead, future research directions should focus on several key areas:

1. Diversity of Plant Sources: Expanding the range of plant species and their parts (leaves, roots, fruits, etc.) that are studied for antioxidant properties can lead to the discovery of novel bioactive compounds.

2. Advanced Extraction Techniques: Utilizing modern extraction methods, such as ultrasound-assisted extraction or supercritical fluid extraction, can enhance the yield and purity of bioactive compounds from plant extracts.

3. Mechanism of Action: Further research into the molecular mechanisms by which plant extracts exert their antioxidant effects can provide deeper insights into their therapeutic potential.

4. Combinatorial Studies: Investigating the synergistic effects of combining different plant extracts or their bioactive compounds can reveal new avenues for potent antioxidant formulations.

5. Clinical Trials: Moving beyond in vitro and animal studies, clinical trials are essential to validate the health benefits of plant extracts in humans.

6. Sustainability and Scalability: Addressing the environmental impact and scalability of plant extract production is crucial for their widespread adoption in various industries.

7. Bioavailability and Metabolism: Understanding how plant antioxidants are absorbed, metabolized, and excreted can inform the development of more effective formulations.

8. Safety and Toxicity: Rigorous safety assessments are necessary to ensure that the use of plant extracts does not pose unforeseen health risks.

By pursuing these research directions, the scientific community can continue to unlock the full potential of plant extracts as natural antioxidants, contributing to advancements in health, agriculture, and environmental sustainability.