Review on tannins: Extraction processes, applications and possibilities

Das, Atanu Kumar; Islam, Md. Nazrul; Faruk, Omar; Ashaduzzaman, Md.; Dungani, Rudi

doi:10.1016/j.sajb.2020.08.008

Cited by 241 publications

(167 citation statements)

References 175 publications

Supporting

Mentioning

156

Contrasting

Unclassified

Order By: Relevance

“…The presence of tannins in agricultural wastes opens the possibility to obtain them from sustainable and affordable sources. This sustainable approach must further be supported by the continuous search for and optimization of novel extraction methods (i.e., solid liquid, ultrasound, microwave, supercritical fluids or high-pressure extraction) together with the use of green solvents [ 2 , 28 ]. Then, obtaining added-value products from underutilized by-products contributes to the development of a circular economy.…”

Section: Introductionmentioning

confidence: 99%

By-Products of Agri-Food Industry as Tannin-Rich Sources: A Review of Tannins’ Biological Activities and Their Potential for Valorization

Fraga-Corral

Otero

Echave

et al. 2021

Foods

View full text Add to dashboard Cite

During recent decades, consumers have been continuously moving towards the substitution of synthetic ingredients of the food industry by natural products, obtained from vegetal, animal or microbial sources. Additionally, a circular economy has been proposed as the most efficient production system since it allows for reducing and reutilizing different wastes. Current agriculture is responsible for producing high quantities of organic agricultural waste (e.g., discarded fruits and vegetables, peels, leaves, seeds or forestall residues), that usually ends up underutilized and accumulated, causing environmental problems. Interestingly, these agri-food by-products are potential sources of valuable bioactive molecules such as tannins. Tannins are phenolic compounds, secondary metabolites of plants widespread in terrestrial and aquatic natural environments. As they can be found in plenty of plants and herbs, they have been traditionally used for medicinal and other purposes, such as the leather industry. This fact is explained by the fact that they exert plenty of different biological activities and, thus, they entail a great potential to be used in the food, nutraceutical and pharmaceutical industry. Consequently, this review article is directed towards the description of the biological activities exerted by tannins as they could be further extracted from by-products of the agri-food industry to produce high-added-value products.

show abstract

Section: Introductionmentioning

confidence: 99%

By-Products of Agri-Food Industry as Tannin-Rich Sources: A Review of Tannins’ Biological Activities and Their Potential for Valorization

Fraga-Corral

Otero

Echave

et al. 2021

Foods

View full text Add to dashboard Cite

show abstract

“…In the in vitro studies, as proposed in this work, it is described that the substances that cause precipitation of proteins on the surface of the epithelium promote healing, as observed in the case of tannins [21][22][23][24][25][26] . Therefore, since the test was performed using fixed histological sections, it was not possible to test the stimulation of these substances by the tincture; however, the precipitation capacity (proteolysis) of collagen and elastic fibers was studied, which is directly related to the effectiveness of the healing process.…”

Section: Discussionmentioning

confidence: 99%

Employing optical microscopy technique to determine the tissue action of Hamamelis virginianaL. (Hamamelidaceae), Maytenus ilicifoliaMart. ex Reissek (Celastraceae) and Casearia sylvestris Sw. (Salicaceae) tinctures on skin-fixed histological sections of Wistar rats

Dezena

Ireno

Silva

2021

Rev. Ciênc. Farm. Básica Apl.

View full text Add to dashboard Cite

Objective: In this study, we aimed to determine the action of the tinctures of Hamamelis virginiana, Maytenus ilicifolia, and Casearia sylvestris on tissues. For this, we investigated the histological sections of fixed skin tissue of Wistar rats for the changes in collagen and elastic fibers, epithelial cells, conjunctive cells, epidermal attachments, pigments, and granules using the optical microscopy technique. Since in the literature and published articles, the use of in vivo models, such as Wistar rats, is predominant to evaluate the healing action of herbal medicines. Methods: The tinctures of Hamamelis virginiana, Maytenus ilicifolia, and Casearia sylvestris, and ethanol 70% (blank) were used. The tinctures were obtained at 10% (w/v) through percolation using 70% ethanol (v/v) as the extraction liquid. This study was conducted in duplicate for each tincture and different incubation times (4, 24, and 48 h) at 37 °C in an oven. The slides used in this study (Wistar rat skin) were previously processed at the histology laboratory since the waste material was donated to conduct this experiment. The Research Ethics Committee approved the use of animals of the Life Sciences Center of the Pontifical Catholic University of Campinas (PUC-CAMPINAS) under the protocol approval number 367/08. Before initiating the staining process, the slides were removed from the oven, and the tincture deposited on the slides was removed. Weigert staining was performed subsequently. For semi-quantitative analysis, the histological sections were carefully observed, and the number of collagen and elastic fibers was evaluated based on the following scale: (+) normal fiber presence, (−) slight decrease, (− −) moderate decrease, and (− − −) intense decrease. The images were digitally captured to obtain the results using a photomicroscope. Results: The degradation of collagen fibers was best evidenced upon using Hamamelis virginiana tincture, which is concordant with the existing reports in the literature on its healing action via the precipitation of dermal proteins. Maytenus ilicifolia and Casearia sylvestris tinctures exhibited low proteolytic capacity as they only caused degradation of elastic fibers that are more delicate and very different from collagen in their constitution. Therefore, the application of the latter two as healing agents (which acts through precipitating proteins) is limited. Conclusions: This experimental histological model using the optical microscopy technique exhibits the advantage of agility and high efficiency as a simple and powerful approach.

show abstract

“…However, the extraction process remains a challenge due to their heterogeneity character and compositions. Recently, various extraction processes, technological applications and their pros and cons were reviewed and appeared in leading scientific reports [117][118][119]. Due to similar tannin structural properties as that of synthetic phenols, the basis of wood adhesives was started in the middle of 1940s.…”

Section: Biocomposites Using Tanninsmentioning

confidence: 99%

Opportunity of Non-Wood Forest Products in Biocomposites

Sharma¹

2022

Biocomposites

View full text Add to dashboard Cite

In recent years industries are attempting to decrease their dependency on petroleum-based fuels and products due to increased environmental issues. The tremendous increase in production and use of plastics in every sector of life has led to huge plastic waste disposal problems and also an environmental threat. In order to prevail over the present scenario, the viable and cost-effective approaches are to prepare eco-friendly bio-composites based on non-wood forest products (NWFP), a part of forest wealth of the globe, especially natural fibres, agricultural wastes and extractives. Natural fibres and extractives have many advantages viz. low density, low cost, considerable toughness properties, nontoxicity, sustainability and biodegradability. NWFP based composites may be utilized to produce non-structural parts for diverse applications in various industries as high-performance materials with interesting properties for specific applications viz. furniture, thermal, acoustic insulations and automotive industries etc. In the present chapter, opportunities of extractives, cellulosic and lignocellulosic fibres from non-wood forest products in Bio-composites will be discussed.

show abstract

Review on tannins: Extraction processes, applications and possibilities

Cited by 241 publications

References 175 publications

By-Products of Agri-Food Industry as Tannin-Rich Sources: A Review of Tannins’ Biological Activities and Their Potential for Valorization

By-Products of Agri-Food Industry as Tannin-Rich Sources: A Review of Tannins’ Biological Activities and Their Potential for Valorization

Employing optical microscopy technique to determine the tissue action of Hamamelis virginianaL. (Hamamelidaceae), Maytenus ilicifoliaMart. ex Reissek (Celastraceae) and Casearia sylvestris Sw. (Salicaceae) tinctures on skin-fixed histological sections of Wistar rats

Opportunity of Non-Wood Forest Products in Biocomposites

Contact Info

Product

Resources

About