11.9
생체분해란 특히 균류에 의해 원치 않는 재료 변형이 일어나는 것을 말하며, 이는 유기 기판(종이, 목재, 섬유)과 무기 기판(돌, 석고, 유리) 모두를 손상시킵니다. 비생물적 붕괴와 달리, 생물 퇴화는 물리적 교란과 화학적 분해를 초래하는 생물학적 활동에서 비롯됩니다.
…
생물 퇴화는 미생물, 특히 곰팡이의 생물학적 활동에 의해 고대 종이, 나무, 돌, 뼈와 같은 재료가 원치 않는 변형을 일으키는 현상입니다.
곰팡이의 생분해는 물리적, 화학적 메커니즘 모두를 포함합니다.
물리적으로 균사는 기질 물질을 침투하여 정착하여 생물굴 형성, 균열, 섬유 분리, 표면 침식을 일으킵니다.
화학적으로 곰팡이는 셀룰라아제나 리그니나아제와 같은 효소를 분비하여 목재나 종이의 구조적 고분자를 더 단순한 분자로 분해하여 이를 먹이로 흡수합니다.
뼈와 같은 광물질이 풍부한 화석에서는 곰팡이가 방출하는 유기산이 pH를 낮추고 광물을 녹여 2차 지각을 형성하여 물질을 약화시킵니다.
또한 멜라닌과 같은 곰팡이 색소와 미네랄 부산물이 재료를 염색합니다.
예방 전략은 곰팡이 성장을 지원하는 환경 조건을 최소화하는 데 중점을 둡니다.
여기에는 습도와 온도 조절, 먼지 축적 감소, 그리고 물과의 직접적인 노출 방지가 포함됩니다.
항진균 치료제나 보호 항균 코팅은 추가 손상을 막을 수 있습니다.
View the full transcript and gain access to JoVE Core videos
Q1: What causes biodeterioration of historical materials?
Biodeterioration is the undesirable alteration of materials like ancient papers, wood, stone, and bone caused by biological activity, especially fungi. Fungi damage materials through both physical mechanisms—such as hyphal penetration causing biopitting and fiber separation—and chemical mechanisms involving enzyme secretion and organic acid production that degrade structural polymers and dissolve minerals.
Q2: How do fungal enzymes break down organic materials?
Fungi secrete hydrolytic enzymes including cellulases and ligninases that degrade structural polymers in wood and paper into simpler molecules, which fungi then absorb as food. These enzymes break down cellulose, lignin, and other organic polymers, causing progressive weakening and decomposition of the substrate material.
Q3: What role do organic acids play in fungal biodeterioration?
Fungi excrete organic acids such as oxalic and citric acid that lower pH and dissolve minerals in bone and fossil materials. On mineral-rich substrates, these acids form secondary crusts and weaken structural integrity. Additionally, siderophores released by fungi solubilize metals, further altering the substrate composition and microbial ecology.
Q4: How do fungal biofilms enhance material deterioration?
Fungi commonly exist within biofilms containing bacteria, algae, or lichens that enhance microbial adhesion and protect organisms from environmental stress. These biofilms support cooperative metabolism, resulting in layered and progressive deterioration. The complex community structure accelerates both physical and chemical damage to substrates.
Q5: What environmental factors support fungal growth on materials?
High humidity, elevated temperature, dust buildup, and direct water exposure create conditions favoring fungal colonization. Preventive strategies focus on controlling these environmental factors to minimize biodeterioration. Reducing moisture and maintaining stable temperature are critical for protecting vulnerable materials from fungal attack.
Q6: How can antifungal treatments prevent biodeterioration?
Antifungal treatments and protective antimicrobial coatings prevent further fungal damage once colonization occurs. When biodeterioration is detected, identification via microscopy or DNA-based tools guides targeted antifungal applications. Combined with environmental control measures, these treatments help preserve historical and culturally significant materials.
Q7: What staining effects do fungal pigments cause on materials?
Fungal pigments such as melanins and quinones penetrate deeply into porous materials, causing often irreversible staining. These pigments, along with mineral byproducts from fungal metabolism, discolor substrates. Biomineralization processes, where fungi precipitate minerals like calcium oxalate crusts, further contribute to visible damage and material weakening.