Analysis of Volatile Organic Compounds Differences of Black and White Pepper by HS-GC-IMS and HS-SPME-GC-MS

Abstract

Rationale

As a medicinal and edible herb, Piper nigrum L. is abundant in volatile organic compounds (VOCs), and its essential oil has antibacterial properties. Notably, the aromatic profiles of black pepper (BP) and white pepper (WP) are markedly distinct. Consequently, it is essential to comprehensively characterize the VOCs of BP and WP, and analyze the differences in their VOCs and antibacterial efficacy.

Methods

This study analyzed the VOCs of BP and WP using headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The fingerprint of HS-GC-IMS was established. Random forest analysis, orthogonal partial least squares discriminant analysis and heatmap were used to analyze differences in BP and WP. Furthermore, the antibacterial efficacy of volatile oils derived from BP and WP was assessed using the antibacterial zone diameter method.

Results

A total of 108 and 123 VOCs were identified by HS-GC-IMS and HS-SPME-GC-MS, respectively. The results of multivariate statistical analysis showed that the VOCs of BP and WP are significantly different. In contrast, WP has a milder smell than BP, while BP has a more pungent odor. Eight differential markers were selected. Both BP and WP had inhibitory effects on Staphylococcus aureus and Candida albicans.

Conclusion

This study helps to decipher the flavor differences between BP and WP, and provides a material basis for their quality control and pharmacodynamics. It is beneficial to enhance its utilization within the domains of nutrition and traditional Chinese medicine.