Table 3.
Extraction methods of MDC and their advantages and disadvantages.
| Sources | Extraction method | Principle | Advantages | Disadvantages | References |
|---|---|---|---|---|---|
| Mussel byssus | Pepsin solutions | Pepsin is typically indiscriminate in its digestion of proteins, with the notable exception of the triple helical domain of native collagen with further limited pepsin digestion, the cross-linked molecules at the telopeptide region are cleaved without damaging the integrity of the triple helix. | •Ensure the integrity of the collagen molecule | (17) | |
| Axinella cannabina; Suberites carnosus | Alkaline solubilization, trypsin solubilization | The first method was initially introduced for the isolation of insoluble collagen (InSC) from G. cydonium and C.reniformis by employing an alkaline, both denaturing and reducing, homogenization buffer affording collagen in high yield;The second one utilizes a trypsin-containing extraction buffer, known to destroy the interfibrillar matrix and, therefore, releasing the collagen fibrils (ICC). After exhaustive water extraction, the remaining debris generally comprises the spongin/spongin-like collagen. | •Reagent residues in collagen; •Generate abundant waste liquid; •Resulting in environmental pollution |
(16) | |
| Surf clam shell (Coelomactra antiquata) | Guanidine hydrochloride and pepsin | •Safer; •Cheape; •More moderate; •Less destructive than acid hydrolysis |
(23) | ||
| Indian major carp rohu (Labeo rohita) | Enzymatic method | (90) | |||
| Bigeye tuna | Acetic acid and pepsin | (70) | |||
| Shark (Prionace glauca) and ray (Zeachara chilensis and Bathyraja brachyurops) | Acidic and enzymatic extractions | (91) | |||
| Codfish skin | An acid-base procedure | •Ineffective with byssal threads | (20) | ||
| Salmon Byproducts | Bacterial extracellular proteases fermentation | The proteases secreted by marine bacteria play an important role in the decomposition of organic nitrogen in oceans. | •Potential bioactive peptides would be released; •The reaction time is shortened. |
(92) | |
| Nile tilapia (Oreochromis niloticus) skin | Collagen extraction after fermentation pretreatment | •Type I collagen with high purity; •Retained the integrity of their triple helical structure. |
(93) | ||
| Jellyfish (Acromitus hardenbergi) | Physical-aided acid-assisted extraction method | Increase physical intervention. | •Similar amino acids composition; •Retained high molecular weight distributions; |
(88) | |
| Takifugu flavidus | Electrodialysis extraction | This method can purify charged proteins/peptides by ion-exchange membranes through a stimulated diffusion process under the influence of electric potential difference. | •High efficiency; •Large capacity; •High extraction yield; •Better environmental sustainability |
(94) | |
| Freeze drying and electrospinning processes | (40) | ||||
| Tilapia | Electrospinning | •Simple operation | (36) |