TY - JOUR
T1 - Characterization of Carrageenan Extracted from Hypnea bryoides in Oman
AU - Al-Alawi, Ahmed Ali
AU - Al-Marhubi, Insaaf Mohammed
AU - Al-Belushi, Mohammed Said Moosa
AU - Soussi, Bassam
N1 - Funding Information:
This work was supported by HM Sultan Qaboos Trust Fund (SR/AGR/FOOD/05/01, PI: B Soussi), University of Gothenburg and the Swedish Research Council (K2005-73-00536, PI: B. Soussi). The authors thank Barry P. Jupp for the valuable discussions; Rabea Al Maqbaly, and Suleiman Al Sheili for their technical assistance.
PY - 2011/10
Y1 - 2011/10
N2 - Carrageenophyte red seaweed from Oman, Hypnea bryoides, extracted using three different processes: an aqueous, a mild alkaline, and a more vigorous alkaline extraction was investigated. The resulting extract precipitated by alcohol was subject to chemical and rheological measurements. The total carbohydrate [ranged from 36.78 to 41.65 g/100 g], and ash [39.04 to 43.11 g/100 g] were the most abundant components in H. bryoides and contrary to the two, lipid content was found at a minimum [ranging from 2.95 to 3.38 g/100 g]. Alkali treatment with NaOH allowed complete conversion of kappa (κ) carrageenan form as detected by FTIR analysis. Total yield by alkali treatments gave higher yields (33%) compared with aqueous treatments (12%). However, subsequent aqueous treatment produced mixed carrageenan (μ and κ) with higher molecular weight compared with the alkali treatments which produced single carrageenan form (κ) with molecular weight of 4.1 × 10 5 Da. The effects of thermal history on gel-sol and sol-gel transition were investigated by differential scanning calorimeter (DSC) and rheology on a pure sample and 1.5% κ-carrageenan mixture added with 30 mM KCl. Transition temperatures from DSC and rheology showed comparable results and were in good agreement with those previously reported.
AB - Carrageenophyte red seaweed from Oman, Hypnea bryoides, extracted using three different processes: an aqueous, a mild alkaline, and a more vigorous alkaline extraction was investigated. The resulting extract precipitated by alcohol was subject to chemical and rheological measurements. The total carbohydrate [ranged from 36.78 to 41.65 g/100 g], and ash [39.04 to 43.11 g/100 g] were the most abundant components in H. bryoides and contrary to the two, lipid content was found at a minimum [ranging from 2.95 to 3.38 g/100 g]. Alkali treatment with NaOH allowed complete conversion of kappa (κ) carrageenan form as detected by FTIR analysis. Total yield by alkali treatments gave higher yields (33%) compared with aqueous treatments (12%). However, subsequent aqueous treatment produced mixed carrageenan (μ and κ) with higher molecular weight compared with the alkali treatments which produced single carrageenan form (κ) with molecular weight of 4.1 × 10 5 Da. The effects of thermal history on gel-sol and sol-gel transition were investigated by differential scanning calorimeter (DSC) and rheology on a pure sample and 1.5% κ-carrageenan mixture added with 30 mM KCl. Transition temperatures from DSC and rheology showed comparable results and were in good agreement with those previously reported.
KW - Algae
KW - FTIR
KW - Hypnea bryoides
KW - Phycocolloids
KW - Seaweed
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U2 - 10.1007/s10126-010-9350-7
DO - 10.1007/s10126-010-9350-7
M3 - Article
C2 - 21240534
AN - SCOPUS:80051671251
SN - 1436-2228
VL - 13
SP - 893
EP - 899
JO - Marine Biotechnology
JF - Marine Biotechnology
IS - 5
ER -