Preparation and Characterisation of the Siddha Polyherbal Formulation Koduveli Nei: Physicochemical, HPTLC, GC-MS and FTIR Characterisation

Abstract

Background: Koduveli Nei (KN) is a polyherbal medicated castor-oil (Nei) preparation used in Siddha medicine, prepared as described in the classical text Vaatha Nithanam-800 for Vaatha-predominant musculoskeletal conditions, including lumbar spondylosis. Although Koduveli Nei is traditionally indicated for such spinal degenerative conditions, KN lacks validated pharmacopoeial standards, which limits quality assurance and regulatory acceptance; this study does not evaluate therapeutic efficacy but addresses this standardisation gap.
Objective: This study aimed to standardise a single prepared batch of KN following the Pharmacopoeial Laboratory for Indian Medicine (PLIM) protocol and WHO/Unani Pharmacopoeia guidelines.
Methods: Organoleptic characters, solubility profile, physicochemical parameters (rancidity, acid, saponification, iodine, and peroxide values, specific gravity, and refractive index), HPTLC fingerprinting at 254 nm, 366 nm, and 520 nm (derivatised), heavy metal content by ICP-OES (arsenic, cadmium, mercury, lead), microbial load and specific pathogen screening, aflatoxin content, and pesticide residue screening were assessed.
Results: All safety parameters tested were within permissible limits: heavy metals were below the instrument detection limit, microbial counts and pathogen screening met WHO/Unani Pharmacopoeia criteria, aflatoxin content was within commonly cited permissible limits, and pesticide residues were below the quantification limit. HPTLC fingerprinting showed 11, 10 and 14 peaks at 254 nm, 366 nm and 520 nm respectively, reproducible across all three replicate tracks. GC-MS profiling of Koduveli Nei in hexane, chloroform and methanol identified squalene, tocopherols and fatty acid methyl esters. FTIR of Koduveli Nei contained functional groups corresponding to the compounds identified by GC-MS. Conclusion: These findings suggest KN contains lipophilic antioxidant and anti-inflammatory constituents. The physicochemical, HPTLC, GC-MS and FTIR data together establish a preliminary analytical reference profile for this single batch of KN, supporting its safety as tested and providing a basis to guide further multi-batch standardisation of this classical Siddha formulation.
Key Findings
Koduveli Nei met WHO/PLIM safety limits for heavy metals, microbial load, aflatoxins, and pesticide residues, and yielded a reproducible three-wavelength HPTLC fingerprint (11/10/14 peaks) together with a GC-MS- and FTIR-supported lipophilic antioxidant and anti-inflammatory constituent profile in this single batch