What are Tannins?
Tannins are a diverse group of polyphenolic compounds that are widely distributed in the plant kingdom. They are secondary metabolites produced by plants as a defense mechanism against herbivores, pathogens, and environmental stressors. Tannins are chemically characterized by their ability to bind and precipitate proteins, which imparts astringency and bitterness to various plant tissues, such as leaves, stems, roots, fruits, and seeds. They are also present in certain beverages, including tea and wine, contributing to their characteristic flavors and health benefits.
Tannins can be broadly classified into two main categories based on their chemical structures and hydrolysis behavior:
- Hydrolyzable Tannins: These are esters of polyhydric alcohols, typically glucose, with phenolic acids, such as gallic acid and ellagic acid. Hydrolyzable tannins are readily hydrolyzed in the presence of acids or enzymes, releasing their constituent components.
- Condensed Tannins: Also known as proanthocyanidins or flavan-3-ols, these are oligomers or polymers of flavan-3-ol units, such as catechin and epicatechin. Condensed tannins are less susceptible to hydrolysis and are known for their strong protein-binding capacity.
Tannin Analysis Service Provided by Creative Proteomics
Tannin Content Determination: Accurate quantification of total tannin content in plant samples for nutritional and industrial applications using validated methods.
Tannin Profiling and Characterization: Comprehensive analysis of tannin diversity and structural characterization in various plant tissues through advanced mass spectrometry-based approaches, including Liquid Chromatography-Mass Spectrometry (LC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS).
Tannin Metabolite Identification: Identification and quantification of specific tannin metabolites using tandem mass spectrometry (MS/MS) to elucidate their chemical structures and concentrations.
Tannin-Enzyme Interaction Studies: Investigation of tannin interactions with enzymes using state-of-the-art mass spectrometry techniques to explore potential biological activities and enzyme inhibitory properties.
Tannin Quantification in Food and Beverages: Determination of tannin content in food and beverage products for quality control using advanced analytical techniques such as High-Performance Liquid Chromatography (HPLC) coupled with UV or MS detection.
Tannin Analysis in Animal Feeds: Analysis of tannins in animal feeds using mass spectrometry methods to understand their impact on nutrition and animal health.
Environmental Tannin Analysis: Assessment of tannin content in environmental samples using mass spectrometry to study ecosystem dynamics, supported by Liquid Chromatography-Mass Spectrometry (LC-MS) or Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS) techniques.
Tannin Analysis in Medicinal Plants: Analysis of tannin content in medicinal plants using mass spectrometry to discover potential bioactive compounds, often coupled with chromatographic methods.
Customized Tannin Analysis: Tailored analytical approaches designed to meet specific research needs, utilizing various mass spectrometry and chromatographic techniques based on the research requirements.
Data Interpretation and Reporting: Comprehensive data interpretation and reporting for actionable results, provided by our team of experienced scientists and experts.
Tannin Analysis Techniques: Mass Spectrometry-Based Approaches
- Liquid Chromatography-Mass Spectrometry (LC-MS): LC-MS is a powerful technique for separating and detecting tannins in complex mixtures, providing information on their molecular weight and fragmentation patterns. Common LC-MS instruments used for tannin analysis include Agilent 1290 Infinity II LC System coupled with Agilent 6545 Q-TOF.
- Gas Chromatography-Mass Spectrometry (GC-MS): GC-MS is suitable for the analysis of volatile tannins and their derivatives. It involves the conversion of tannins into volatile derivatives, followed by GC separation and MS detection.
- Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-MS): MALDI-MS is particularly useful for the analysis of high molecular weight tannins and tannin-protein complexes.
Workflow for Plant Metabolomics Service
List of Tannin Metabolites and Derivatives Analyzed (including but not limited to)
Hydrolyzable Tannins:
| Category |
Metabolites |
| Gallotannins |
Gallagic acid, Ellagic acid, Galloyl glucose |
| Ellagitannins |
Punicalagins, Tellimagrandin I, Pedunculagin |
| Complex Tannins |
Oenothein B, Lambertianin C, Camelliatannin A1 |
Condensed Tannins:
| Category |
Metabolites |
| Proanthocyanidins |
Epicatechin, Catechin, Gallocatechin |
| Theasinensins |
Theasinensin A, Theasinensin B |
| Theaflavins |
Theaflavin, Theaflavin-3-gallate |
Sample Requirements for Tannin Assay
| Sample Types |
Minimum Sample Size |
| Plant Samples |
Roots, stems and leaves, floral parts, fruits/seeds, rhizomes, buds/tender leaves, tissue sections, pollen, bark, trunk/wood, resin/gum, resin acids, seedlings/young plants, rhizosphere soil, root exudates. |
100 mg - 1 g |
| Animal Samples |
Tissues |
100 mg - 1 g |
| Cell Samples |
Cells and Culture |
106 - 108 cells |
Applications of Tannin Analysis
Food and Beverage Industry: Tannin analysis is crucial for assessing the quality and sensory attributes of food and beverages, such as wines, teas, and fruits. It provides insights into tannin content, which impacts flavor, color, and mouthfeel.
Pharmacological Studies: Tannin analysis helps in identifying bioactive compounds with antioxidant, anti-inflammatory, and anticancer properties. It supports drug discovery and development in pharmacological research.
Plant Biology and Ecology: Tannin analysis aids in understanding the ecological functions of tannins in plants, including defense mechanisms against herbivores and pathogens.
Nutritional Research: In animal nutrition, tannin analysis provides insights into tannin's effects on nutrient availability and digestion, contributing to balanced diet formulations.
Medicinal Plant Research: Tannin analysis characterizes the chemical composition of medicinal plants, identifying potential bioactive compounds for traditional medicine practices and pharmaceutical applications.
Environmental Studies: Tannin analysis assesses tannin content in soils, plant material, and water samples, providing insights into their impact on ecosystem dynamics and nutrient cycling.
Biochemistry and Enzymology: Tannin analysis studies tannin-enzyme interactions and enzyme inhibitory properties, offering valuable insights into enzymatic processes.
Agriculture and Crop Research: Tannin analysis helps study tannin's impact on crop quality, plant growth, and responses to environmental stressors, advancing agricultural practices.
Waste Management: Tannin analysis assesses tannin content in waste materials, exploring potential applications in bioremediation or utilization.
Chemotaxonomy: Tannin analysis differentiates plant species based on their tannin profiles, aiding in botanical identification.
Case 1. Tannin Content in Mangrove Plants of Segara Anakan Lagoon, Indonesia
Background:
Mangroves are vegetation found in intertidal zones between marine and terrestrial ecosystems, offering various ecosystem services such as carbon sequestration and pollution reduction. Tannins are important compounds found in mangrove plants and have diverse applications, including protection against pathogens and potential use in various industries.
Samples:
The study was conducted in Segara Anakan Lagoon, Central Java, Indonesia. A total of 342 samples were collected from 19 dominant mangrove species, including stems, barks, and leaves.
Methods:
1. Study Area:
Segara Anakan Lagoon, Cilacap District, Central Java, Indonesia
2. Sample Collection Procedure:
Vegetation Samples: Collected from 37 sampling sites in the lagoon, including mangrove stems, barks, and leaves. Three replicates of each tree part for each species were collected, resulting in 342 samples from 19 dominant mangrove species.
Sample Extraction: Tannin extraction was done using the maceration method. Mangrove powder was mixed with 70% ethanol, left for 24 hours, and then evaporated using a rotary evaporator. Leaves were blended with 70% ethanol, filtered, and further treated with 70% ethanol.
3. Analysis of Tannin Content Procedure:
UV-Visible Spectrophotometry: Used to measure the percent and weight of tannins in the extracted samples. Absorbance method at 280 nm was used for the analysis.
4. Data Analysis:
Clustering Tannin Content: Euclidian distance analysis was used to identify species with similar tannin percentages.
Distribution of Tannin Across Plant Parts: Tannin distribution in mangrove plant parts was analyzed using table stock analysis, determining initial, minimum, maximum, and average stock.
Distribution of Tannin Across Landscape: Tannin distribution across the landscape was constructed based on the percentage and weight of tannins from different mangrove species, helping develop species zonation.
5. Classification of Mangrove Tannin Percentage:
Frequency class analysis was used to classify tannin percentages of different mangrove species, grouping them based on their tannin content potentials.
6. Regression Analysis:
A regression analysis was performed to understand the relationship between potential tannin content (in kg) and the diameter of mangrove trees
Results
The study revealed that tannins were mainly present in barks and stems, contributing to 67% of the total tannin content, while leaves accounted for 33%. Various mangrove species exhibited different tannin percentages, with Xylocarpus moluccensis, Excoecaria agallocha, Nypa fruticans, and Heritiera littoralis having the highest tannin content. Cluster analysis showed specific groupings of mangrove species based on tannin composition and content, indicating distinct characteristics among different clusters. The total tannin content in mangrove plants ranged from 0.59 to 158.96 kg per tree for barks and stems, and from 0.20 to 91.65 kg per tree for leaves. The study highlighted the potential of certain mangrove species as a raw material source for the tannin industry.
The dendrogram of clustering analysis of mangrove species in Segara Anakan Lagoon, Cilacap, Indonesia based on tannin content
Reference
- Hilmi, Endang, et al. "Tannins in mangrove plants in segara anakan lagoon, central java, indonesia." Biodiversitas Journal of Biological Diversity 22.8 (2021).
