Nutritional, Spectral and Thermal Characteristic of Lamiaceae Seeds

Aims: Species of the family Lamiaceae possess a rich tradition of use for flavoring and medicinal purposes. This paper focusses on the nutritional and thermal characteristics of the seeds from eight species belonging to this family: Gmelina arborea Roxb. ex Sm., Hyptis suaveolens (L.) Poit., Leonotis nepetifolia (L.) R.Br., Ocimum americanum L., Ocimum sanctum L. (Rama Tulsi), Ocimum tenuiflorum L. (Krishna Tulsi), Origanum vulgare L. and Tectona grandis L.f.

Methodology: The oil, starch, total polyphenol, flavonoid and mineral contents for aforementioned seeds were determined. Fourier-transform infrared (FTIR) spectroscopy was used to assess the phytoconstituents. Thermogravimetric/derivative thermogravimetric analyses (TG/DTG) and differential scanning calorimetry (DSC) analyses were performed to analyze the decomposition patterns.

Results: The concentrations of oil, starch, total polyphenol, flavonoids and minerals for the seeds from the eight plants under study ranged from 11.8 to 50.4%, from 0.22 to 1.84%, from 295 to 5842 mg/kg, from 1660 to 12680 mg/kg and from 11756 to 33927 mg/kg, respectively. Unsaturated oils, polyphenols and lignin were recognized by vibrational spectroscopy. The sequence of thermal effects in the seed pyrolysis process above 100°C have been put in relation to seed protein crystallization (endotherm at 200°C), oxidation reactions and degradation of hemicellulose and other fiber components (at around 300°C), and decomposition of polyunsaturated (at 357°C) and mono-unsaturated (at 391°C) triglycerides.

Conclusion: Lamiaceae seeds are potential food alternatives to cereals.