Prospective Randomized Controlled Pilot Study of Gut Microbiome Modulation by Nigella Sativa Seed Oil and Thymoquinone Metabolism in Healthy Volunteers

Influence of Thymoquinone on the Human Gut Microbiome

For many patients, the additive use of dietary supplements without side effects is motivating for therapy and enhances quality of life. The oil of the plant Nigella sativa (NS), a dietary supplement containing Thymoquinone (TQ) as its main active compound, exhibits hepatoprotective effects through antioxidative, antifibrotic, and anti-inflammatory properties, and also demonstrates anticancer and antiapoptotic activities. In vitro and in vivo studies have shown that TQ can also influence the gut microbiome. However, no clinical studies are currently available that describe the specific extent of TQ's influence on the human intestinal microbiome and its potential effects on the outcome after gastrointestinal surgery.

The aim of the project is therefore to investigate changes in the human microbiome following the intake of Nigella sativa seed oil capsules containing TQ as the main active ingredient. The study will test the hypothesis that TQ, through its diverse mechanisms of action, modulates the composition of the microbiome and thereby exerts a positive effect on immune response and intestinal healing processes. In parallel, TQ metabolites in urine will be analyzed using Liquid Chromatography-Mass Spectrometry (LC-MS) to gain insights into the pharmacokinetic profile of the compound.

Study Overview

• Status: Completed
• Conditions: Changes in Human Gut Microbiome in Healthy Adults
• Intervention / Treatment: Dietary supplement: Intake of Thymoquinone (TQ) containing Nigella Sativa Seed Oil (NSSO) capsules

• Study Type: Interventional
• Enrollment (Actual): 8
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Thuringia
    • Jena, Thuringia, Germany, 07747
      • Jena University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• no recent medication use
• no history of gastrointestinal surgery
• no pregnancy
• no allergies to NSSO or its derivatives
• healthy
• 18 years and above

Exclusion Criteria:

• regular medication
• history of gastrointestinal surgery
• pregnancy
• allergies to NSSO or its derivates
• presence of chronic illness
• below the age of 18 years

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Treatment group; Intake of two TQ-containing NSSO capsules three times daily for 20 days and fecal sampling at five time points.	Dietary supplement: Intake of Thymoquinone (TQ) containing Nigella Sativa Seed Oil (NSSO) capsules; Intake of two Thymoquinone (TQ) containing Nigella Sativa Seed Oil (NSSO) capsules three times daily for 20 days and provision of fecal samples at five time points.
No Intervention: Control group; Fecal sampling at five time points without supplementation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Changes in bacterial taxa in fecal samples	From enrollment to the end of treatment at 20 days.

Collaborators and Investigators

• Sponsor: Aysun Tekbaş
• Collaborators: Interdisciplinary Center of Clinical Research of the Medical Faculty Jena

Publications and helpful links

General Publications

• Tekbas A, Huebner J, Settmacher U, Dahmen U. Plants and Surgery: The Protective Effects of Thymoquinone on Hepatic Injury-A Systematic Review of In Vivo Studies. Int J Mol Sci. 2018 Apr 5;19(4):1085. doi: 10.3390/ijms19041085.
• Tekbas A, Bremer-Streck S, Wissenbach DK, Peters FT, von Lilienfeld-Toal M, Soonawalla Z, Rauchfuss F, Settmacher U, Dahmen U. Gas Chromatography-Mass Spectrometry Detection of Thymoquinone in Oil and Serum for Clinical Pharmacokinetic Studies. Int J Mol Sci. 2023 Nov 17;24(22):16431. doi: 10.3390/ijms242216431.

Study record dates

Study Major Dates

• Study Start (Actual): April 2, 2024
• Primary Completion (Actual): March 1, 2025
• Study Completion (Actual): March 1, 2025

Study Registration Dates

• First Submitted: March 1, 2026
• First Submitted That Met QC Criteria: March 1, 2026
• First Posted (Actual): March 5, 2026

Study Record Updates

• Last Update Posted (Actual): March 5, 2026
• Last Update Submitted That Met QC Criteria: March 1, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Thymoquinone, Gut microbiome, Nigella sativa seed oil, Microbiota modulation, Thymoquionone metabolism
• Additional Relevant MeSH Terms: Pharmaceutical Preparations; Dosage Forms; Capsules
• Other Study ID Numbers: 2024-3273-BO; ACSP08 (Other Grant/Funding Number: Interdisciplinary Center of Clinical Research, Medical Faculty of Friedrich Schiller Universit)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The microbiome datasets will be shared online.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No