Comparative Studies on Egyptian and Libyan Roselle Seeds as a Source of Lipid and Protein

Abstract

Proceeding from the fact that the seeds of Roselle plant are full of nutritional constituents, however in Egypt and Libya, they are often discarded as a by-product, this study aims to evaluate the nutritional composition of Roselle seeds grown in Egypt and Libya as a source of oil and protein besides making a comparison between whole chemical composition of Roselle seeds grown in both countries. Ground of whole Egyptian and Libyan Roselle seeds powder contained high amount of protein (31.02% ± 0.93% and 28.67% ± 0.45%), crude fat (21.6% ± 0.66% and 16.94% ± 0.86%) and total ash (6.89% ± 0.11% and 5.60% ± 0.10%), respectively. However, Egyptian seeds have moisture content, protein, crude fat and total ash higher than Libyan seeds. Crude oil from Egyptian seeds had high refractive index and iodine value in comparison with crude oil from Libyan seeds. There were no remarkable differences between both seeds in acidity percent, unsaponifiable matters percent and saponification value. Linoleic, oleic and palmitic acids were the major fatty acid constituents in Egyptian Roselle seeds. Meanwhile linolenic, linoleic, oleic, stearic, palmitoleic and palmitic acids were the major fatty acid constituents in Libyan Roselle seeds. Crude oil from Egyptian seeds had higher percent of unsaturated fatty acids than crude oil from Libyan seeds. Unsaponifiable matters constituents for extracted oil from Egyptian seeds were free from n-pentacosane (C25) and rich in n-hexacosane (C26). Oil from both seeds had the same content of Beta sito-sterol and stigma-sterol. Both seeds were rich in glutamic acid, aspartic acid, arginine and leucine. Libyan seeds were rich in essential amino acids in comparison with Egyptian seeds. Finally nutritional comparison of Roselle seeds variation depends on the variety, location and environmental conditions during cultivation. Roselle seeds are a good source for extraction of oil and protein. Protein from Roselle seeds could be used as a supplement material for poor food in lysine.

Chemistry, phytotechnology, pharmacology and nutraceutical functions of kenaf ( Hibiscus cannabinus L.) and roselle ( Hibiscus sabdariffa L.) seed oil: An overview

“…The major saturated fatty acids in roselle seed oil are palmitic (20.84%) and stearic (5.88%) acids and the main unsaturated fatty acids are linoleic (39.31%) and oleic (32.06%) acids. The proportion of unsaturated fatty acids was greater than the saturated fatty acids (Elneairy, 2014). Therefore, roselle seed oil is of unsaturated type and can be classified in the oleic-linoleic acid group .…”

“…The physical properties like specific gravity, melting point and refractive index of seed oil were determined according to AOAC (1990). Roselle seed oil was also extracted by soaking in petroleum ether (3:1 ratio of solvent to crushed seeds) for 24 h with shaking at 40-60 • C following removal of solvent from collected miscella by using rotary evaporator at 40 • C under vacuum (Elneairy, 2014). Studies by previous investigators revealed that roselle seed oil possess higher specific gravity than corn oil.…”

Evaluation of Chemical, Nutritional and Antioxidant Characteristics of Roselle (Hibiscus sabdariffa L.) Seed

“…Similar results had previously reported by Atat and Imaizumi (2002); Mohamed et al (2007) and Rehab and Ayman (2017), who observed that linoleic, oleic and palmitic acids were the most important fatty acids in the Roselle seed oil (27,13,28). In another study, which was done by Elneairy (2014), the fatty acid composition of two species of Roselle seeds (Egypt and Libya) was compared. The results showed that the amounts of linoleic, oleic, palmitic and stearic acids of the oil obtained from the Egyptian species were 38.17, 33.31, 18.15 and 4.09 %, respectively, while their amounts in the oil extracted from Libya species were 17.50, 16.50, 12.70 and 15.97%, respectively (29).…”

“…In another study, which was done by Elneairy (2014), the fatty acid composition of two species of Roselle seeds (Egypt and Libya) was compared. The results showed that the amounts of linoleic, oleic, palmitic and stearic acids of the oil obtained from the Egyptian species were 38.17, 33.31, 18.15 and 4.09 %, respectively, while their amounts in the oil extracted from Libya species were 17.50, 16.50, 12.70 and 15.97%, respectively (29). It is important to note that differences between the amount of fatty acids obtained in the present study and that of the previous studies can be due to differences in species, climatic and environmental conditions, and the maturity period of the plant, which can affect the amount and ratio of fatty acids (15).…”

Profil Minyak Biji dari Empat Varietas Rosela Herbal (Hisbiscus sabdariffa var. sabdariffa) Indonesia

“…Asam lemak jenis lain juga ditemukan dalam minyak biji rosela, meskipun dengan jumlah yang sedikit, asam lemak tersebut adalah asam stearat (C18:0). Hasil serupa dilaporkan oleh penelitian lain yang menyebutkan bahwa kandungan asam lemak utama pada minyak biji varietas Rosela dari Mesir adalah asam oleat, linoleat dan palmitat (Elneairy, 2014;El-Deab & Ghamry, 2017). Profil senyawa asam lemak dalam minyak biji rosela herbal menunjukkan adanya variasi jenis dan kuantitas asam lemak pada empat varietas yang berbeda (Tabel 2).…”