Table 2 Vibrational bands in fucoidan and laminarin

428

C–O–C + C–C–C ring deformation

Carbohydrate [14]

486

571

δ(C–C–O) + τ (C–O)

Carbohydrate [14]

592

608

δ(C–C–O)

Carbohydrate [14]

668

726

δ(C–C–O)

Carbohydrate [14]

826

C–O–S stretching, α-1.3 bond

Fucoidan

C–O–S stretching

α-pyranose [15], C–O–S of

eq. sulfate ester on C-2 [16]

888

δ(C–C–H) + δ(C–O–C)

Carbohydrate [17]

C–O–S stretching

equatorial sulfate ester of a

pyranoid sugar [18, 19]

ν(C–O) in C–O–C linkage, β(C–O–H)

Carbohydrate [13]

1004

Aromatic ring breathing

Aromatic compound from

Maillard reaction

β(C–O–H) + ν(C–C), C–O–S Stretching

Trisaccharide [13], fucoidan

1054

ν(C–O) + ν(C–C) + δ(C–O–H)

Carbohydrate [14]

1080

ν(C–O) + ν(C–C) + δ(C–O–H)

Carbohydrate [13, 14]

1119

ν(C–O) + ν(C–C) + δ(C–O–H)

Carbohydrate [14]

C–O–C + C–O–S stretching hfill

Fucoidan

1148

ν(C–O–C) + ν(C–C) in glycosidic linkages,

Carbohydrate [13]

asymmetric ring breathing

ν(C–O)

Glucose [13]

1203

ν(C–C) + ν(C–O)

Carbohydrate [14]

S–O stretching

Sulfate ester [17]

S–O stretching

Sulfate ester shoulder

1262

δ(C–C–H) + δ(C–C–H) + δ(C–O–H)

Carbohydrate [14]

1335

ν(C–O) + δ(C–O–H), δ(C–H)

Carbohydrate [14],

Alginate [20]

1366

δ(C–H) stretch

MG alginate [20]

CH₃ bending, symmetric

Carbohydrate [18]

C–H deformation

Melanoidin

O–H rocking

Monosaccharide

1456

δ(C–H) + δ(CH₂) + δ(C–O–H), CH, CH₂

(in plane) + C–O–H deformations + asymm

Carbohydrate [14],

Alginate [20]

COO-

1529

–C=C– (in plane) + vasym COO-

Carotenoids [21],

Alginate [20]

ν(O–C–N)

Amide II [22]

δ(C–C–H) + v(C=C)

Amide [23], Melanoidin [24]

1614

ν asym COO-

Alginate [20]

1627

ν(C–C) + v(C=O)

Amide [25], Melanoidin

ν(C=O) + ν(C=C) + ν(C=N)

Amide I [23], Melanoidin [24],

unhydrated β-sheets [26, 27]

1664

ν(C=O) stretching

Acetylamide [28]

ν(CH₃) stretch, symmetric

v(CH₂) stretch, symmetric

Carbohydrate [22]

C-H stretching

Carbohydrate [18]

O–H stretching

Carbohydrate [15]