Antidiabetic and anti-inflammatory potential of sulphated polygalactans from red seaweedsKappaphycus alvareziiandGracilaria opuntia

Abstract

Antidiabetic and anti-inflammatory potential of sulphated polygalactans isolated from the red seaweeds Kappaphycus alvarezii and Gracilaria opuntia were acquired by employing different in vitro systems. The sulphated galactopyran motif derived from G. opuntia possessed significant antidiabetic properties as identified by α-amylase (IC 50 0.04 mg/mL), α-glucosidase (IC 50 0.09 mg/mL) and dipeptidyl peptidase-4 (DPP-4, IC 50 0.09 mg/mL) inhibitory activities. Based on the detailed nuclear magnetic resonance spectroscopy experiments the sulphated galactopyran motif of G. opuntia was designated as →3)-4-O-sulfonato-(6-O-acetyl)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-(2-O-sulfonato)-α-D-galactopyranosyl-(1→3)-4-O-sulfonato-(6-O-acetyl)-β-D-xylosyl-(1→3)-4-O-sulfonato-(6-O-acetyl)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-(2-O-sulfonato)-α-D-galactopyranan, while the one from K. alvarezii was demonstrated to be →4)-4-O-sulfonato-(2-Omethyl)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-(2-O-methyl)-α-D-galactopyranan. The sulphated galactans from G. opuntia showed greater antiinflammatory inhibitory activities as determined by cyclooxygenase-1 (COX-1, IC 50 0.01 mg/mL), cyclooxygenase-2 (COX-2, IC 50 0.03 mg/mL), and 5-lipoxygenase inhibitory activities (5-LOX, IC 50 0.24 mg/mL). This study revealed that the sulfated polygalactan enriched concentrate from G. opuntia can be used as potential therapeutic candidate to suppress the hyperglycemic response in diabetic conditions and inflammatory activity. They can be used to develop functional food ingredient in nutraceutical products.

Therapeutic Uses of Red Macroalgae

“…However, seaweed species have α-amylase and α-glucosidase inhibitory actions [ 72 ]. The sulfated galactans extracted from Gracilaria opuntia was responsible for the antidiabetic properties through the deactivation of α-glucosidase, a-amylase, and dipeptidyl peptidase-4 [ 73 ]. Laurencia dendroidea could be a natural source for the production of antidiabetic agents [ 74 ].…”

Advanced Pharmacological Uses of Marine Algae as an Anti-Diabetic Therapy

“…According to the results, sulfated galactans isolated from Gracilaria opuntia (IC50 0.09 mg/mL) significantly inhibited the DPP-4 enzyme than the sulfated galactans of Kappaphycus alvarezii (IC50 0.12 mg/mL) compared to the standard diprotin A (IC50 1.54 mg/mL). The observed activity might be due to the reaction between functional groups of sulfated polygalactan with DPP-4 by H-bonding and hydrophilic interactions [45]. Similarly, aqueous, alkaline, and a mixture of aqueous/alkaline fractions of a red seaweeds Palmaria palmate have exhibited a potent inhibitory effect on DPP-4 enzyme with IC 50 of 2.52 ± 0.05 mg/ml, 4.60 ± 0.09 mg/ ml, and 4.24 ± 0.02 mg/ml respectively [46].…”

Purification and identification of a novel antidiabetic peptide from Chinese giant salamander (Andrias davidianus) protein hydrolysate against α-amylase and α-glucosidase

“…[23] Contrary, most of the α-glucosidase inhibitors are sugars or sugar derivatives. [5] However, the most active compounds with antidiabetic potential were isolated in different materials like Try-Tyr-Pro-Leu peptide from Sardine muscle hydrolysate, [42] Gln-Pro-Gly-Arg from silkworm pupae with amino acid sequence and peptide KLPGF from albumin hydrolysate.- [43] Nevertheless, mechanisms by which protein hydrolysates, bioactive peptides and amino acids control glucose levels is still elusive owing the involvement of complex series to archive the goal of inhibition or regulation of glucose uptake in peripheral tissue. Thus, this results provide considerable and intense demand for further study.…”

“…This incompleteness results in a high level of plasma glucose and consequently lead to the distortion of the immune system, blood vessel, and nerve. [4,5] Moreover, lifestyle change associated with bad eating habits, less exercise, and aging is another hallmark for the ever-increasing of diabetic especially type 2. [3] Therefore, paying more attention in diagnosis and assure suitable treatments is required to prevent or reduce diabetes-related short-term consequences and complications such as eye sight problem, tiredness, and hyperglycemia and long-term ones like chronic renal failure, cardiovascular disease, and neuropathy.…”

“…Many studies underlying the beneficial and mechanism of the bioactive peptide in type 2 diabetes prevention have been elucidated. [5,17] For instance, anti-diabetic peptide from animal source comprises Sardine, [18,19] Shark liver, [20] Atlantic salmon skin gelatin, [21] Silver Carp, [2] Cocoon and Silkworm, [22,23] Egg white, and Yolk. [6,[24][25][26] Notably, a numbers of studies have suggested plant like Guava leaves, [27] Selaginella tamariscina, [28] Phaseolus coccineus, [29] and Nepalese medicinal Bergenia ligulata [4] to have antidiabetic properties.…”