Review on tannins: Extraction processes, applications and possibilities

Tannins are polyphenolic compounds naturally found in vegetables. Their presence in nature has prompted their historical use in many different ways. The revision of their traditional utilization has allowed their further modification aiming for an industrial application. Sometimes these modifications have implied the addition of harmful substances such as formaldehyde, classified as a carcinogen of category B1. In other cases, these natural tannins have been replaced by synthetic compounds that threaten human and animal health and damage the environment. Therefore, currently, both academy and industry are searching for the substitution of these unsafe complexes by the increasing inclusion of tannins, natural molecules that can be obtained from several and diverse renewable resources, modified using harmless additives. To achieve promising results, cost-efficient and eco-friendly extraction methods have been designed. Once these green alternatives have been isolated, they have been successfully applied to many fields with very assorted aims of utilization such as coagulants, adhesives, floatation agents, tannings, dyes, additives, or biomolecules. Therefore, this review offers a global vision of the full process that involves the tannin's technological application including an overview of the most relevant tannin sources, effective extraction methods, and their utilization in very diverse fields.

https://www.mdpi.com/1420-3049/25/3/614/pdf

Technological Application of Tannin-Based Extracts.

Today, there is increasing interest in discovering new bioactive compounds derived from ethnomedicine. Preparations of guava (Psidium guajava L.) leaves have traditionally been used to manage several diseases. The pharmacological research in vitro as well as in vivo has been widely used to demonstrate the potential of the extracts from the leaves for the co-treatment of different ailments with high prevalence worldwide, upholding the traditional medicine in cases such as diabetes mellitus, cardiovascular diseases, cancer, and parasitic infections. Moreover, the biological activity has been attributed to the bioactive composition of the leaves, to some specific phytochemical subclasses, or even to individual compounds. Phenolic compounds in guava leaves have been credited with regulating blood-glucose levels. Thus, the aim of the present review was to compile results from in vitro and in vivo studies carried out with guava leaves over the last decade, relating the effects to their clinical applications in order to focus further research for finding individual bioactive compounds. Some food applications (guava tea and supplementary feed for aquaculture) and some clinical, in vitro, and in vivo outcomes are also included.

Health Effects of Psidium guajava L. Leaves: An Overview of the Last Decade

https://hal.archives-ouvertes.fr/hal-01925978/document

Tannins extraction: A key point for their valorization and cleaner production

A Review of Property Enhancement Techniques for Carrageenan-based Films and Coatings.

This study aims to determine the antimicrobial activities of tannin extracts from guava leaves against pathogens microbial. The method used for qualitative analysis with the tannins are formed by the intensity of the color is blackish green FeCl3 compounds. In the quantitative analysis of tannins used variations of organic solvent (ethanol with a concentration of 30 %, 50 %, 70 % ). Levels of tannins in the sample solution was calculated with Tannates Acid Equivalent ( EAT ). Test of antimicrobial activities using diffusion agar method. The results showed levels of tannins in leaves of guava with ethanol 30 %, the which is 2.351 mg /g, ethanol 50 % is 1.728 mg g, ethanol 70 % is 1.835 mg / g. The best solvent to extract the highest levels of tannins with ethanol 30 % by value of tannin levels 2.351mg /g. Tannin inhibitory activity on five different pathogens microbial. This is because the composition of the cell wall of the microbe fifth different. The results showed that the tannins extracts can inhibit the growth of Escherichia coli,Pseudomonas aureginosa, Staphilococcus aureus, Aspergillus niger and Candida albicans. Tannins are polyphenolic compounds that are very complex. The effectiveness of antibacterial compounds found in plant tannins eg guava leaves is influenced by the concentration of tannins. The higher levels of tannin antibacterial activity will increase. Preliminary studies to study the antibacterial activity of guava leaf has been implemented Faharani (2008 )(5), where the results showed that the water extract of guava leaves have antibacterial activity against E. coli at a concentration of 40 %, whereas in S. aereus extract showed no inhibitory activity, and the active compound is believed to have antibacterial activity of flavonoids, tannins and saponins. In guava leaves contain tannin by 9 %, which can be used as an antibacterial. Tannins can be used as an antibacterial because it has a phenol group, so that the tannins have properties like alcohol is an antiseptic that can be used as an antimicrobial component. Therefore this study is to assess the antimicrobial activity of tannin extracts from guava leaves against several pathogens microbial.

/pdf/antimicrobial-activities-of-tannins-extract-from-guava-xc8x04mhob.pdf

Antimicrobial Activities Of Tannins Extract From Guava Leaves (Psidium Guajava L) On Pathogens Microbial

Research has been conducted to determine the levels of tannins in leaves of guava (Psidium guajava L) using a variation of the concentration of organic solvent. The method used for qualitative analysis with the tannins are formed by the intensity of the color is blackish green FeCl3 compounds. While the principle of quantitative determination of tannins is tanat acid standard curve at a wavelength of 724,5 nm. In the quantitative analysis of tannins used variations of organic solvent (ethanol and acetone with a concentration of 30%, 50%, 70%). Levels of tannins in the sample solution was calculated with Tannates Acid Equivalent (EAT). The results showed levels of tannins in leaves of guava with 30% ethanol, which is 3.228 mg/g, 50% is 2.970 mg/g, 70% is 2,333 mg/g. While the levels of tannins in guava leaves with 30% acetone solvent which is 2,781 mg/g, 50%: 2,738 mg/g, 70%: 2,405 mg/g.

/pdf/tannin-extract-of-guava-leaves-psidium-guajava-l-variation-33h2lomr9q.pdf

Tannin Extract Of Guava Leaves (Psidium Guajava L) Variation With Concentration Organic Solvents

A study has been conducted to determine the use of Caulerpa sp. Edible coatings on fresh steaks tuna against the presence of microbes during storage at chilling temperatures. In this research, two applied method of edible coating is used, that is dipping and immersion method, with chilling temperature (5°C), storage time (0, 3, 6, 9 days). Each treatment is compared to control (without an edible coating). The results showed that the application of edible coating Caulerpa sp in fresh steaks tuna with soaking and dipping method showed total bacteria increase during storage, but still fulfill the microbiological quality of fresh fish that is maximum total plate 5.0 × 105 cfu/g. Total microbes in fresh steaks tuna were soaked with immersion methods and stored up to 9 days: 2.3 × 105 cfu/g while total microbial on fresh steaks tuna were dipped by dipping method and stored up to 9 days ie 3.4 × 105 cfu/g. So it can be concluded that application method of edible coating Caulerpa sp on fresh steaks tuna soaked better than the method of dipping.

https://iopscience.iop.org/article/10.1088/1755-1315/89/1/012014/pdf

Analysis Total Plate Counte (TPC) On Fresh Steak Tuna Applications Edible Coating Caulerpa sp During Stored at Chilling Temperature

The aim of the research was to study the antioxidant activity of crude extract of seaweed Padina sp. The process of extraction of seaweed Padina sp. was done by using maceration stages namely the solvent n-hexane, and then using solvent extraction followed by ethyl acetate and methanol. Solvents that are still left in the third crude extract was evaporated by using a rotary vacuum evaporator, and then tested for DPPH free radical activity (1,1-diphenyl-2-picrylhydrazyl) by UV-VIS spectrophotometer at a wave length of 517 nm. Measurement of antioxidant activity of crude extract of seaweed Padina sp. performed at a concentration of 50 ppm, 100 ppm, 150 ppm, 200 ppm and 250 ppm. Data from tested for DPPH free radical were analyzed using linear regression, than followed by determination of IC 50. The test results of all three antioxidant activity of crude extract of seaweed Padina sp. indicated that the higher concentration of solvent, the higher the percentage of arrests of radical activity or percentage inhibition. The antioxidant activity of methanol crude extract of seaweed Padina sp. to give IC50 value of 200.88 mg/L, crude extract of ethyl acetate to give IC50 value of 483.09 mg/L and extract crude n-hexane gave IC50 value of 900.00 mg/L. This means that the antioxidant activity of methanol crude extract of seaweed Padina sp. was stronger than that of crude extract of ethyl acetate and n-hexane. Indeks Terms : sea grass, Padina sp., antioxidant ————————————————————

/pdf/potential-of-seaweed-padina-sp-as-a-source-of-antioxidant-2672fqviqg.pdf

Potential Of Seaweed Padina Sp. As A Source Of Antioxidant

Green seaweed Caulerpa sp is found in several coastal waters in Indonesia and is used as fresh vegetables by people in the growing habitat area This study aimed to conduct a review of the potential of Caulerpa sp as functional food The development of this paper is a literature review of relevant writings to determine the position of sea grapes Caulerpa sp as functional food Data and relevant information are displayed in the form of figures and tables Caulerpa seaweed grows naturally and is available throughout the year Caulerpa contains crude fiber and secondary metabolites which positions Caulerpa as a functional food ingredient The components of superior nutrition in Caulerpa are minerals, proteins, fats, and carbohydrates The superiority of Caulerpa as a food ingredient is its processing which is very simple and brief and does not require food additives in the form of dyes and essences

https://iopscience.iop.org/article/10.1088/1755-1315/517/1/012021/pdf

Meigy Nelce Mailoa

Papers

Antimicrobial Activities Of Tannins Extract From Guava Leaves (Psidium Guajava L) On Pathogens Microbial

Tannin Extract Of Guava Leaves (Psidium Guajava L) Variation With Concentration Organic Solvents

Analysis Total Plate Counte (TPC) On Fresh Steak Tuna Applications Edible Coating Caulerpa sp During Stored at Chilling Temperature

Potential Of Seaweed Padina Sp. As A Source Of Antioxidant

Seaweed Caulerpa sp position as functional food