Capsici Fructus Veterinary Grade API is supplied as a standardised botanical active substance derived from the dried ripe fruits of Capsicum annuum L. and/or Capsicum frutescens L. Three model designations define the physical architecture: CF-VET/API-P100 is a milled powder, CF-VET/API-M25 is a micronised suspension-grade powder, and CF-VET/API-G80 is a roller-compacted granule. The material is controlled specifically for veterinary dosage-form manufacture covering tablets, injections, capsules, powders, granules, premixes, and solutions. Its release specification combines assayed total capsaicinoids with a controlled natural ratio of capsaicin to dihydrocapsaicin, heavy metal limits, residual solvent limits, particle-size distribution, and microbiological absence criteria.

Specification and Identity Attributes for Veterinary Multi-Route Processing

Release testing is performed on each batch. Identification is confirmed by HPLC retention time against capsaicin and dihydrocapsaicin reference standards, with assay determined by reversed-phase HPLC with UV detection at 280 nm. Total capsaicinoids are controlled to 95.0–105.0% of the declared value on a dried basis. The capsaicin-to-dihydrocapsaicin ratio is not less than 0.8, which distinguishes native Capsici Fructus from isolated synthetic capsaicin and from many oleoresins that are selectively depleted in dihydrocapsaicin during solvent extraction. Residual solvent analysis follows ICH Q3C and Ph. Eur. 2.4.24. The product is not sterile and is not intended for direct administration without further processing.

The three model designations differ primarily in particle-size architecture. CF-VET/API-P100 is milled to D90 ≤150 µm and is used for wet granulation, capsule blending, and intermediate powder processing. CF-VET/API-M25 is jet-milled under nitrogen to D90 ≤25 µm, reducing oxidation during size reduction and enabling suspension-based injection and fine dispersion in liquid vehicles. CF-VET/API-G80 is roller-compacted and sieved so that 80% of the granule mass lies between 150 µm and 500 µm. The granule model is selected when segregation in low-dose premix operations must be minimised, because its particle-size envelope aligns with common lactose and grain carriers.

Why Is Particle Size Control More Critical Than Capsaicinoid Assay in Low-Dose Premix Uniformity?

In premix and low-dose powder operations, the dominant process variable is physical segregation. Capsaicinoid-rich fines carry electrostatic charge below 30% relative humidity and adhere to stainless steel blender walls, producing assay depression in successive stratified samples. The G80 sieve fraction is therefore controlled more tightly than the P100 powder specification. In a ribbon blender of 500 L working volume, geometric dilution is required when the API inclusion rate is below 1.0% w/w. The first premix stage combines API with an equal mass of carrier; the carrier mass is then doubled stepwise until the batch is complete. This staged dilution reduces relative standard deviation of capsaicinoid content below 5.0% across 10 sampling points in a finished feed premix. Published data for CF-VET/API-G80 at inclusion rates below 0.1% w/w is limited; homogeneity should be confirmed by HPLC on at least 10 stratified samples per batch.

For tablet and capsule manufacturing, direct compression is constrained by poor powder flow and a tendency to smear under compaction pressures above 250 MPa. The P100 grade is therefore processed by wet granulation with povidone K30 or by dry granulation on a roller compactor at roll pressures from 40 to 70 bar. Granules are compressed on a rotary tablet press at 10–20 kN main compression force. Magnesium stearate is added at 0.5–1.0% w/w, but lubrication time is held below 5 min because extended blending reduces tablet tensile strength by up to 30% through surface coating of capsaicinoid-rich particles. Hardness is adjusted to 60–90 N for immediate-release tablets, and disintegration is tested in water at 37°C with a limit of 15 min according to Ph. Eur. 2.9.1. Capsule filling on a dosator machine requires conditioned bulk powder at 40–50% relative humidity; content uniformity is checked by Ph. Eur. 2.9.40. Compatibility with acid-resistant capsule shells has not been systematically published for this specific botanical API, so preliminary dissolution testing is mandatory.

When a Non-Aqueous Injection Vehicle Is Selected Over Aqueous Solvent Systems

Parenteral use is limited by capsaicinoid solubility and thermal sensitivity. Capsaicin is practically insoluble in water and freely soluble in ethanol, acetone, and several fixed oils. Aqueous injection vehicles therefore require co-solvents or emulsification. CF-VET/API-M25 is dispersed in medium-chain triglycerides or ethyl oleate at a controlled D90 ≤25 µm. Terminal sterilisation at 121°C for 15 min is a critical control point. Published data on terminal sterilisation of this specific suspension is limited, so stability-indicating HPLC should be performed after autoclaving. Nitrogen overlay during filling reduces oxidative degradation of the vanillyl moiety. Alkaline aqueous systems above pH 8.0 are incompatible because capsaicinoid hydrolysis accelerates; residual moisture in the vehicle should remain below 0.5% w/w. For injectable solutions rather than suspensions, filtration through a 0.22 µm membrane is possible only after complete dissolution in a suitable solvent system. Suspensions cannot be filtered through sterilising membranes without removing the active particles.

For oral solutions, the API is dissolved in PEG 400, ethanol, or a fixed oil. Concentrations up to 10% w/w are prepared under light protection because ultraviolet exposure accelerates capsaicinoid photodegradation. Amber glass or opaque high-density polyethylene containers with closed closures are used. Dissolved capsaicinoids are not detected by plate-count methods; only HPLC quantification of the sum of capsaicin and dihydrocapsaicin is stability-indicating. Powders and granules intended for in-feed use are blended with carriers such as lactose monohydrate, wheat semolina, or limestone flour. For transfer drops above 2 m, a vibratory feeder or anti-segregation cone is recommended, because fine capsaicinoid particles can migrate during free-fall transfer and reduce assay uniformity in the lower discharge fractions.

Comparative Behaviour Against Crude Fruit Powder, Oleoresin, and Synthetic Capsaicin at Equivalent Declared Pungency

At equivalent declared pungency, the main difference is not capsaicinoid content alone but matrix consistency. Crude fruit powder varies from 0.1% to 1.0% total capsaicinoids and may carry pesticide residues and microbial contamination exceeding 10⁵ CFU/g. Oleoresin provides capsaicinoids in a viscous solvent-extracted liquid that is difficult to disperse in dry tablet and premix operations unless adsorbed onto excipients. Synthetic capsaicin is a single molecule with high purity but lacks the natural congener ratio and is unsuitable for products required to remain within a botanical definition. CF-VET/API models are standardised to a total capsaicinoid assay range, controlled particle size, and microbial limits. Model selection is therefore based on downstream unit operation rather than a generic capsaicinoid claim.

Storage below 25°C in a dry, light-protected container is required. Once opened, the material should be used within 30 days if ambient relative humidity exceeds 60%. Avoid combining with strong oxidising agents, alkali hydroxides, or chlorinated solvents under alkaline conditions. The product is not sterile; parenteral applications require terminal sterilisation or aseptic processing. For any use outside the described dosage forms, compatibility with the final container closure system and stability-indicating HPLC must be verified before release.