Biodegradable polymer which, edible films have gained more attention due to their environmentally-friendly characteristics, vast variety and availability, non-toxicity, and low cost. Biodegradable polymers have a long history, and since many are natural products, the precise timeline of their discovery and use cannot be accurately traced. One of the first medicinal uses of a biodegradable polymer was the catgut suture, which dates back to at least 100 AD. The first catgut sutures were made from the intestines of sheep, but modern catgut sutures are made from purified collagen extracted from the small intestines of cattle, sheep, or goats. The concept of synthetic
Bolon (musical instrument) hits the calabash as if playing a drum. Bolon (musical instrument) The bolon is a traditional harp played in Mali, as well as Guinea. It was notably played in hunting ceremonies or before a battle, to rouse warriors' valor. It was also used by the Jola in Gambia for accompaniment for men's choruses. Among other string instruments played in Guinea, the bolon is the oldest. The bolon is a three-stringed instrument, constructed from a large calabash covered by unshaven goat skin, and a bow-shaped neck. When playing, it is placed between the legs with the strings facing the musician. In