## 3 Results and Discussion
### The Effect of Fruit Enzymes at Differential Concentration on the Change of Various Floaters
However, the collagenase activity of bromelin was twice higher than papain activity in the laboratory. In several studies, it has been found that papain has cathepsin K, which could cut Types I and II collagen and adjust the degradation. Furthermore, cathepsin L is also similar to papain-like collagenase and would efficiently cut Type I primarily and other collagens. Therefore, papain has the functions of cathepsin collagenases and degrades various types of collagens and ECM components [36]. Additionally, papain plays an important role in many biologic functions such as protein cleaving, cell dissociation and even necrotic tissue treatment. Papain has good efficacy in controlling inflammation, so it has often been used to treat arthritis and bronchitis. The preliminary studies of 11 fractions of low-molecular-weight collagen peptides obtained through enzymatic hydrolysis were investigated. It was then suggested papain may be used to dissolve the vitreous opacity and get rid of ocular floaters. Combined with papain, bromelin treatment has higher collagen solubility. In clinics, doctors may use papain to reduce pain and inflammation from trauma from surgery, aid digestion, heal wounds, relieve herpes zoster symptoms, kill parasitic worms and insects, control psoriasis and hypertension and lower blood sugar [37]. However, it has been found that papain increases bleeding tendency and decreases platelet aggregation which could be beneficial for preventing strokes. In our study, we also found that ocular floaters from proliferative diabetic retinopathy with VH could disappear by the antithrombotic ability of papain. In addition, papain could boost the potency of the anticoagulants such as aspirin and warfarin. Very few papain consumers develop rashes, unapparent breathing constriction and mild chest pain. Therefore, papain intake is relatively safe. Finally, fiction is a fruit enzyme that is derived from a latex substance from the trunk of Ficus carica. This proteinase, fiction, belongs to the serine protease family and the mechanism of vitreolysis is like the function of coriplasmin [38]. Moreover, enzymatic activity of fiction depends on the sulfhydryl group of a cysteine residue at the active sites. It also belongs to a family of cysteine endopeptidase that includes fiction, papain, bromelin, calpain, caspases and cathepsin B. In medical procedures, fiction is used in the production of stitching material (sutures), in the preparation of animal arteries for implantation in people and in blood typing. Ficin breaks down proteins and kills intestinal worms. Moreover, fiction is also used in making cheese and sausage casings and chill-proofing beer. Moreover, it also serves as a preserver, lipolytic agent and mild coagulant. In addition, fiction is sometime included in meat tenderizers in combination with papain and bromelin. We also found fiction has the antioxidation, anti-inflammation, antibacterial activities and whitening effects after intake. Moreover, people can take fiction for digestion problems and to get rid of intestinal worms. Ficin may inhibit mRNA and protein expression levels and be used for proteolytic degradation and solubility of elastin, collagen and various fibers [39; 40]. Furthermore, fiction and bromelin also appears to be equally effective on collagen, while papain is less effective. Recently, fiction was demonstrated to cleave collagen I, II, III and IV. In the slit lamp examination and electron microscopy, we found that insoluble fibrils could be depolymerized to a soluble form by several proteolytic enzymes such as pepsin and fiction. Furthermore, swollen fibrils could be found after digestion by hydrolytic enzymes. We suggested that fiction may be beneficial for cutting collagen fibrils and intermolecular cross-link, thus causing SVOs and floaters to disappear. Previously, we reported that vitreous floaters could be significantly absorbed after a 3-month pineapple supplement [41].