# Diversity and Functional Roles of Microorganisms in Anatolian Black Pine Cone Vinegar Fermentation

## TL;DR

This study explores the microbial diversity and properties of vinegar made from Anatolian Black Pine cones, highlighting its potential for food and health applications.

## Contribution

The paper provides new insights into the microbial composition and functional properties of pine cone vinegar, emphasizing its antimicrobial and antioxidant potential.

## Key findings

- CnB vinegar from Burdur province showed the highest α-terpineol content and strongest antimicrobial activity against E. coli.
- The bacterial microbiome of CnB was dominated by acetic acid bacteria and Proteobacteria, with high culturable microorganism concentrations.
- Sensory evaluations indicated that CnB had a balanced flavor, while CnV and CnM were less favorable due to sharpness and mildness.

## Abstract

The parts of some pine species are a rich source of bioactive compounds that can be used in various food products. The current work, the physicochemical, bioactive, antimicrobial, sensory, and aromatic properties of traditional vinegar produced from Anatolian Black Pine Cones from different provinces of Turkey were determined, as well as the cultivable microbial diversity and metagenomic analysis. The total phenolic content of the vinegars ranged from 163.88 to 174.79 mg GAE/L. Antioxidant activity, measured via DPPH and ABTS assays, varied among the samples. CnB vinegar, made from Burdur province cones, stood out for its bioactive compounds, including terpenes, acetic acid, ascorbic acid, and the highest α‐terpineol content (3.13%). CnB also exhibited the strongest antimicrobial activity, with the largest inhibition zone (44.91 mm) against
E. coli
type A, while CnM showed the lowest activity. Sensory evaluations favored CnB for its balanced flavor, while CnV was criticized for excessive sharpness, and CnM was deemed too mild. The bacterial microbiome of CnB was predominantly composed of acetic acid bacteria, with an average concentration of 7.36 log CFU/mL in the enumeration of culturable microorganisms. The dominant bacterial taxa at the phyla level included Proteobacteria (72.296%), Firmicutes (22.062%), Bacteroidota (3.665%), followed by Acetobacteraceae (71.47%), Clostridia (13.187%), Bacilli (5.066%), Bacteroidetes (3.665%), and C. negativicutes (3.737%) at the phylum level. The fungal microbiome was mainly represented by Ascomycota (78.717%) and Eukaryota Incertae sedis (15.840%). The findings demonstrate that pine cone vinegar can be employed in a multitude of applications, including food preservation and health promotion.

The pine cone vinegar has been analyzed for its microbial community using cultural methods and metagenomic analysis, as well as its aroma components, total phenolic content, antioxidant capacity, and organic acids. The results provide valuable information on the sensory properties, aroma volatiles, antimicrobial effect, and relationship with the microbial community of vinegars produced from Anatolian Black Pine cones.