A recent study published in the Journal of Agricultural and Food Chemistry has shed new light on the potential cognitive benefits of blackcurrants, with Organomation's MICROVAP triple microplate evaporator playing a crucial role in the sample preparation process.
Study Overview
Researchers from The New Zealand Institute for Plant and Food Research conducted a comprehensive investigation into the bioactive compounds in blackcurrants (Ribes nigrum) that may inhibit monoamine oxidase (MAO-A/B) activity. The study employed a randomized, double-blind crossover, placebo-controlled design with 13 adult participants (8 male, 5 female) aged 26-39 years from the wider Palmerston North community in New Zealand. Participants were given either blackcurrant juice (200 mL containing 1.44 g of polyphenols), blackcurrant powder (1.1 g containing 0.48 g of polyphenols), or a placebo, with a 7-day washout period between interventions.
Key Findings
The study identified sarmentosin, a nitrile glycoside, as a novel MAO inhibitor in blackcurrants. This compound was found to effectively inhibit platelet MAO-B activity in human participants after consumption of blackcurrant juice and powder. Specifically:
1. Both blackcurrant juice and powder interventions resulted in >80% inhibition of platelet MAO-B activity 120 minutes post-consumption.
2. Sarmentosin and its hydroxycinnamoyl esters were identified as novel MAO-A/B inhibitors from blackcurrant in vitro.
3. Sarmentosin was demonstrated to inhibit platelet MAO-B activity in vivo, with a peak plasma concentration observed at 120 minutes post-consumption.
4. The study found a positive correlation between MAO-B inhibition and plasma sarmentosin concentrations, as well as with certain mood descriptors related to alertness and reduced mental fatigue.
5. Why the consumption of blackcurrant interventions led to modulations in circulating neurotransmitters, particularly those associated with dopamine and serotonin metabolism.
Analytical Technique Used
The study utilized several advanced chromatography and mass spectrometry techniques to analyze the blackcurrant compounds and their effects that helped to identify the key compounds in blackcurrants, particularly sarmentosin and its esters:
1. Liquid Chromatography-Mass Spectrometry (LC-MS): This was the primary technique used for various analyses, including:
- S9-LCMS screening assay to determine the bioactivity of blackcurrant fractions in inhibiting MAO activity.
- High-resolution LCMS (HR-LCMS) for exact mass searching to deliver molecular formulas
2. Ultra-High Performance Liquid Chromatography (UHPLC): Used for:
- Anthocyanin quantitation in blackcurrant juice and powder interventions.
- Separation of sarmentosin and its esters.
3. Information-Dependent Acquisition (IDA) Enhanced Product Ion (EPI) experiments: These were performed using a 7500 QTrap triple quadrupole/linear ion trap (QqLIT) mass spectrometer coupled to a Shimadzu Nexera LC40 UHPLC to help identify fractions that were most potent in inhibiting MAO activity.
4. Multiple Reaction Monitoring (MRM): Used for quantification of sarmentosin, its esters, and anthocyanins in plasma samples as a condition of UHPLC.
The combination of these chromatography and mass spectrometry techniques provided the researchers with powerful tools for compound separation, identification, and quantification, which were essential for achieving the study's objectives in analyzing the bioactive compounds in blackcurrants and their effects on MAO inhibition. Through this, they were also able to analyze the bioavailability of the compounds in plasma after blackcurrant consumption to determine the efficacy of these compounds in inhibiting MAO activity.
MICROVAP's Role in the Research
Organomation's MICROVAP triple microplate evaporator was instrumental in the sample preparation process for analyzing sarmentosin bioavailability in plasma. Here's a detailed workflow of the sample preparation process:
1. Initial Sample Collection: Venous blood samples (9 mL) were collected into lithium heparin vacutainer tubes.
2. Plasma Separation: Blood samples were centrifuged at 4000 g for 10 minutes at 4°C.
3. Sample Pretreatment:
- Plasma samples were spiked with d4-salicyclic acid glycoside (internal standard, 0.5 ng)
- Samples were acidified
4. Phospholipid Removal:
- Pretreated samples were applied to a Phree phospholipid removal 96-well plate
- Acidified acetonitrile was then added to plate with the mixture previously vortexed prior to the Phree plate
- Filtrate was collected using a 96 Multi-Tier Micro Plate System
5. Sample Concentration Using MICROVAP:
- Filtrate was transferred to the MICROVAP triple microplate evaporator
- Samples were evaporated to dryness under nitrogen at 35°C
6. Sample Reconstitution: Dried samples were reconstituted in H2O ahead of LCMS analysis
7. LCMS Analysis:
- Samples analyzed using a 7500 QqLIT mass spectrometer
- MS data acquired in negative mode using an MRM method
- Sarmentosin quantified using the internal standard ratio method and SCIEX OS software
Implications of the Research
This study's findings have significant implications for the development of functional foods and nutraceuticals targeting cognitive health:
1. Novel MAO Inhibitor: Sarmentosin was identified as a key bioactive compound in blackcurrants, opening new avenues for research into natural MAO inhibitors.
2. Bioavailability: The study demonstrated that sarmentosin and BC anthocyanins are bioavailable in humans after consumption of blackcurrant products.
3. Cognitive Function: MAO-B inhibition by sarmentosin suggests potential benefits for mood and cognitive function.
4. Dosage Insights: The research provided valuable information on effective doses of both blackcurrant powder and juices for achieving MAO inhibition.
5. Product Development: Findings could lead to the development of new blackcurrant-based functional foods or supplements targeting brain health.
The successful use of Organomation's MICROVAP triple microplate evaporator in this cutting-edge research underscores its value in complex analytical processes. By facilitating efficient sample preparation, the MICROVAP contributed to the discovery of important insights into the potential cognitive benefits of blackcurrants.
This study exemplifies how Organomation's equipment continues to support groundbreaking scientific research, furthering our understanding of natural compounds and their effects on human health. The MICROVAP's ability to handle multiple samples simultaneously and maintain precise temperature control was crucial in processing the large number of samples required for this comprehensive human study.
Be sure to contact our team at sales@organomation.com to see how an Organomation sample concentrator could benefit your analysis.