Comparative Profiling of Volatile Compounds in Popular South Indian Traditional and Modern Rice Varieties by Gas Chromatography–Mass Spectrometry Analysis

Abstract

Rice (Oryza sativa L.) is one of the major cereal crops cultivated across the world, particularly in Southeast Asia with 95% of global production. The present study was aimed to evaluate the total phenolic content (TPC) and to profile all the volatile organic compounds (VOCs) of eight popular traditional and two modern rice varieties cultivated in South India. Thirty-one VOCs were estimated by gas chromatography–mass spectrometry (GC-MS). The identified volatile compounds in the 10 rice varieties belong to the chemical classes of fatty acids, terpenes, alkanes, alkenes, alcohols, phenols, esters, amides, and others. Interestingly, most of the identified predominant components were not identical, which indicate the latent variation among the rice varieties. Significant variations exist for fatty acids (46.9–76.2%), total terpenes (12.6–30.7%), total phenols (0.9–10.0%), total aliphatic alcohols (0.8–5.9%), total alkanes (0.5–5.1%), and total alkenes (1.0–4.9%) among the rice varieties. Of all the fatty acid compounds, palmitic acid, elaidic acid, linoleic acid, and oleic acid predominantly varied in the range of 11.1–33.7, 6.1–31.1, 6.0–28.0, and 0.7–15.1%, respectively. The modern varieties recorded the highest palmitic acid contents (28.7–33.7%) than the traditional varieties (11.1–20.6%). However, all the traditional varieties had higher linoleic acid (10.0–28.0%) than the modern varieties (6.0–8.5%). Traditional varieties had key phenolic compounds, stearic acid, butyric acid, and glycidyl oleate, which are absent in the modern varieties. The traditional varieties Seeraga samba and Kichilli samba had the highest azulene and oleic acid, respectively. All these indicate the higher variability for nutrients and aroma in traditional varieties. These varieties can be used as potential parents to improve the largely cultivated high-yielding varieties for the evolving nutritional market. The hierarchical cluster analysis showed three different clusters implying the distinctness of the traditional and modern varieties. This study provided a comprehensive volatile profile of traditional and modern rice as a staple food for energy as well as for aroma with nutrition.

Volatile compounds in two varieties of teff (Eragrostis tef (Zuccagni) Trotter) cultivated in Ethiopia by gas chromatography-mass spectrometry

“…The aldehydes were the main volatile components of the white teff in the n-hexane extract followed by furans, terpene and esters and lower amount of hydrocarbons and pyrrole class of compounds. Ashokkumar et al [25] have identified 31 volatile compounds in the popular South Indian traditional and modern rice varieties among which were squalene and methyl stearate with relative content of 2.5-6.2% and 0.6-1.8%, respectively, and is comparable with the present study. As can be seen in Table 4, the relative contents of main volatile compounds determined in the brown teff sample were 18.4%, 16.0%, 12.5% and 9.73%, for the furfural and 5-methyl-2-furancarboxaldehyde, 2-[(methylthio)methyl]furan, benzeneacetaldehyde, respectively.…”

“…[19] The volatile profiles of most widely consumed cereals have been studied. [1,[20][21][22][23][24][25][26] However, to the best of the researchers' knowledge, no information is available regarding volatile compounds of teff grain [Eragrostis tef (Zuccagni) Trotter] varieties. Hence, the objectives of this study were (i) to optimize the appropriate hydro-distillation time of the white and brown teff grain samples using Clevenger apparatus, (ii) to identify and quantify the volatile compounds present in the white and brown teff grain samples using GC-MS method, and (iii) to investigate the extraction efficiency of dichloromethane and n-hexane solvents toward the volatile compounds present in the white and brown teff grain samples.…”

Extraction of Squalene From Tea Leaves (Camellia sinensis) and Its Variations With Leaf Maturity and Tea Cultivar

“…Squalene is consisted of about 13% human sebum and plays an important role in quenching singlet oxygen in UV-associated skin damage ( 9 ). Squalene has multiple applications in the cosmetics, pharmaceutical, nutraceutical, and food industries owing to its unique physiological and functional properties ( 9 , 28 , 29 ). There was great commercial demand for squalene and the global squalene production volume was 2,500 tons annually, with a value of 93 million dollars in 2013, and is expected to reach 241.9 million dollars by 2022 ( 30 ).…”

Repellency and Toxicity of Selected Fractions, Identified Compounds and Blends of Commiphora africana Resin Against Bedbugs

“…From the assays, compounds present in the most active fraction were identified by Gas Chromatography - Mass Spectrometry (GC-MS) (Shimadzu QP 2010-SE, Japan) by comparing their retention indices (RIs) and the obtained mass spectra with those of the authentic standards from the NIST library. 35 Ultrapure helium was used as the carrier gas at 1 mL/min in a column (A BPX5: 30 m long; 0.25 mm internal diameter; and 0.25 µm film thickness). The GC program was: 50 ˚C (1 min); 5 ˚C/min to 250 ˚C (9 min) with a total run-time of 50 min.…”