# Chemical and Functional Consistency of Condensed Tannins from Anadenanthera macrocarpa at Different Collection Sites

## TL;DR

This study shows that condensed tannins from Anadenanthera macrocarpa are chemically consistent across different environments and have strong antimicrobial and antioxidant properties.

## Contribution

Demonstrates the chemical and functional consistency of A. macrocarpa tannins across varied environmental conditions.

## Key findings

- CTs from A. macrocarpa show similar chemical profiles despite different soil and climate conditions.
- Tannin extracts exhibited 74.81% antimicrobial activity against MRSA at 1000 μg/mL.
- Antioxidant activity was confirmed, supporting biomedical and industrial applications.

## Abstract

Condensed tannins (CTs) are versatile polyphenolic compounds
with
significant industrial potential attributable to their antimicrobial,
antioxidant, and adhesive properties. In this context, the study of
species with a high tannin content and large-scale production capacity
is crucial for expanding commercial applications. Among tannin-rich
species, Anadenanthera macrocarpa (Benth.)
stands out for its high yield and suitability for diverse industrial
uses. However, understanding the influence of edaphoclimatic conditions
on the chemical stability of CTs in this species is essential to ensure
the consistency and quality of the extracted tannin. In this sense,
this study analyzed CT extracts from A. macrocarpa that were collected from three distinct locations with varied soil
and climate conditions. Five plants in consistent vegetative phenological
stages were selected from each site for representative sampling. The
extracts were characterized by using spectroscopic techniques, including
NMR, HSQC, EPR, FTIR, and UV–vis, alongside thermogravimetric
analysis (TGA). Chemical characterizations indicate that samples from
different locations exhibit a similar overall chemical profile within
the sensitivity of the techniques employed, suggesting resilience
to environmental variations and supporting their potential reliability
for large-scale extraction. Additionally, antimicrobial assays were
conducted against bacterial strains, Staphylococcus
aureus and methicillin-resistant
S. aureus (MRSA), at different concentrations. The
highest concentration tested (1000 μg/mL) proved to be the most
effective, exhibiting an antimicrobial activity of 74.81 ± 1.42%,
revealing significant inhibitory effects. The antioxidant activity
was also evaluated, reinforcing their applicability in the industrial
and biomedical fields. Our results indicate that the condensed tannins
extracted from A. macrocarpa exhibit
strong potential for large-scale production, in addition to possessing
antioxidant and antimicrobial activity of interest for various biomedical
applications.