DiaClean® water technology for the postharvest preservation of citrus fruits causes no cytotoxic effect after air-drying and storage
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2017-01-01 |
| Journal | Integrative Food Nutrition and Metabolism |
| Authors | Peter C. Dartsch, Laurent Pupunat |
| Institutions | Scientific Research and Development (Germany) |
| Citations | 2 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: BDD Electrodes for Advanced Postharvest Preservation
Section titled “Technical Documentation & Analysis: BDD Electrodes for Advanced Postharvest Preservation”This document analyzes the research paper “DiaClean® water technology for the postharvest preservation of citrus fruits causes no cytotoxic effect after air-drying and storage” to highlight the critical role of Boron-Doped Diamond (BDD) electrodes and connect the material requirements directly to 6CCVD’s advanced manufacturing capabilities.
Executive Summary
Section titled “Executive Summary”The research validates the use of Boron-Doped Diamond (BDD) electrodes in generating highly effective, yet safe, antimicrobial solutions for postharvest citrus preservation, offering a superior alternative to traditional fungicides.
- Core Achievement: Electrolysis of 1.25% NaHCO3 using BDD electrodes generates transient cytotoxic compounds effective against mold (e.g., Penicillium digitatum).
- Safety Validation: The critical finding is that the cytotoxic compounds are limited to the liquid stage; the washing extract from air-dried, treated fruits showed no cytotoxic effect on L-929 fibroblasts, confirming safety for human health and the environment.
- Material Necessity: BDD electrodes are essential due to their outstanding electrochemical properties, specifically their ability to generate potent Reactive Oxygen Species (ROS), such as hydroxyl radicals and superoxide anion radicals.
- Process Parameters: The effective treatment utilized a controlled electrochemical recipe: 4.0 A current, 8 V voltage, and a total charge of 0.8 Ah/L delivered to the NaHCO3 solution.
- 6CCVD Value: This application requires high-quality, large-area BDD films, a core specialization of 6CCVD, enabling the scale-up and optimization of industrial water treatment systems like DiaClean®.
Technical Specifications
Section titled “Technical Specifications”The following hard data points were extracted from the experimental methodology detailing the electrochemical process parameters and testing conditions.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Electrode Material | Boron-Doped Diamond (BDD) | N/A | Used for high-efficiency electrolysis |
| Electrolyte Concentration | 1.25 | % (w/v) | Sodium Bicarbonate (NaHCO3) solution |
| Electrolysis Current | 4.0 | A | Constant current flow during treatment |
| Electrolysis Voltage (NaHCO3) | 8 | V | Voltage applied during NaHCO3 electrolysis |
| Electrolysis Voltage (Water only) | 25 | V | Voltage applied during supply water electrolysis |
| Total Charge Delivered (Standard) | 0.8 | Ah/L | Standard charge for fruit preservation efficacy |
| Charge Range Tested | 0.05 - 0.8 | Ah/L | Tested range showing charge-dependent cytotoxicity |
| Temperature Control | < 20 | °C | Water temperature maintained via cooling coil |
| Volumetric Flow Rate | 200 | L/h | Throughput rate of the DiaClean® Kit |
| Filtration Size | 0.45 | µm | Porous membrane filter used for sterile aliquots |
| Cytotoxicity Assay Cell Line | L-929 | N/A | Mouse connective tissue fibroblasts (EN ISO 10993-5) |
| Cytotoxicity Exposure Time | 3 | Days | Continuous exposure for vitality measurement (XTT assay) |
Key Methodologies
Section titled “Key Methodologies”The experiment focused on generating and testing the cytotoxic potential of the electrolyzed solution at various stages, confirming the transient nature of the active compounds.
- Electrolyte Preparation: 2.5 L of supply water (15 °C) was mixed with 1.25% (w/v) NaHCO3.
- Electrolysis Setup: The solution was subjected to electrolysis using BDD electrodes in the DiaClean® Kit equipment.
- Controlled Parameters: Current flow was maintained at 4.0 A, voltage at 8 V, and temperature was actively cooled to remain below 20 °C.
- Charge Delivery: Electrolysis continued for 30 minutes to deliver a total charge of 0.8 Ah/L.
- Fruit Treatment: Untreated citrus fruits (oranges, lemons, grapefruits) were dipped for 45 to 60 seconds in the freshly prepared electrolyzed NaHCO3 solution.
- Post-Treatment Processing: Fruits were air-dried for 24 hours and stored for an additional 24 hours at room temperature.
- Cytotoxicity Testing: The air-dried surface residue was washed off with supply water (20 °C). This washing extract was filtered sterile and tested on L-929 fibroblasts using the XTT assay to measure mitochondrial dehydrogenase activity (cell vitality).
6CCVD Solutions & Capabilities
Section titled “6CCVD Solutions & Capabilities”The successful implementation and industrial scaling of electrochemical water treatment systems, such as the DiaClean® technology, rely entirely on the quality and customization of the Boron-Doped Diamond (BDD) electrodes. 6CCVD is uniquely positioned to supply the necessary materials and engineering support for replicating and advancing this research.
Applicable Materials
Section titled “Applicable Materials”The generation of highly reactive species (ROS) requires BDD films with specific doping levels and structural integrity.
- Required Material: Heavy Boron-Doped Diamond (BDD) Wafers and Films.
- 6CCVD provides high-quality MPCVD BDD films optimized for electrochemical applications, ensuring high conductivity and maximized production of hydroxyl radicals (OH•) and superoxide anion radicals (O2•-).
- Substrate Options: We offer BDD films deposited on various substrates, including silicon, niobium, or custom SCD/PCD substrates, depending on the required electrode geometry and current density.
Customization Potential for Industrial Scale-Up
Section titled “Customization Potential for Industrial Scale-Up”The high volumetric flow rate (200 L/h) and industrial application necessitate large, robust, and custom-designed electrodes.
| Requirement | 6CCVD Capability | Technical Advantage |
|---|---|---|
| Large Area Electrodes | Custom plates/wafers up to 125mm (PCD/BDD). | Enables high-throughput industrial reactors necessary for commercial postharvest treatment. |
| Precise Thickness Control | SCD/PCD/BDD films available from 0.1µm to 500µm. | Allows engineers to optimize BDD layer thickness for balancing electrochemical efficiency, cost, and electrode lifespan. |
| Custom Geometries | Advanced laser cutting and shaping services. | We can fabricate BDD electrodes to fit specific reactor designs, ensuring maximum surface area contact for efficient electrolysis. |
| Robust Electrical Contacts | Internal metalization capability (Au, Pt, Pd, Ti, W, Cu). | Essential for creating reliable, corrosion-resistant electrical contacts required for high-current, high-voltage electrochemical processes (e.g., 4.0 A at 8 V). |
| Surface Finish | Polishing services for substrates (Ra < 1nm SCD, < 5nm PCD). | Ensures uniform BDD growth and optimal performance stability over extended operational periods. |
Engineering Support
Section titled “Engineering Support”The research highlights the complex relationship between charge density (Ah/L), storage time, and cytotoxicity. Optimizing these parameters requires deep material and process knowledge.
- Application Focus: 6CCVD’s in-house PhD team specializes in material selection and process integration for advanced electrochemical applications, including Reactive Oxygen Species (ROS) generation and water treatment systems.
- Consultation: We provide expert assistance in defining the optimal BDD doping concentration and film structure required to maximize antimicrobial efficacy while ensuring the rapid decay of cytotoxic intermediates, mirroring the safety profile demonstrated in this study.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
water prior to electrolysis [8][9][10].The technology is based on the idea of using diamond as an electrode material in electrochemistry.Especially BDD electrodes have shown outstanding electrochemical properties in the oxidation of organic and inorganic compounds [11].The reactivity can be mainly associated with the production of hydroxyl radicals [12] or superoxide anion radicals [10].However, the detailed mode of action is currently not well understood as well as its possible potential to generate long-lasting compounds which might be harmful for human health and environment.In this present study, the DiaClean® water technology which is based on the electrolysis of a NaHCO 3 solution with BDD electrodes, was used for citrus fruit preservation.Aliquots of the total mixtures of compounds generated at different stages of the preservation process were used to investigate their effect on vitality of cultured connective tissue fibroblasts, and thus, to evaluate possible health and environmental risks.To our knowledge, the cytotoxicity of the subsequent process stages has not been examined before.