土壌微生物の増殖熱が測定可能な熱量計を用いて，抗菌効果を検討した。抗菌物質の濃度が上昇するにつれ，土壌微生物はグルコースの代謝が低下し，増殖発熱が遅れることから，抗菌活性を表すMIC（生育最小阻止濃度）を高橋らのバクテリア増殖抑制モデルから決定できた。また，TBZのAspergillus nigerに対する防かび評価も，同様にして決定することができた。
Antimicrobial activities were investigated using a calorimeter capable of measuring the heat evolved when soil microbes multiplied in the soil. The peak of heat evolution due to microbial growth with metabolic degradation of glucose in the soil shifted toward a longer incubation as the concentration of antimicrobial agent in soil increased. Their values of MIC (minimum inhibitory concentration) for the antimicrobial activities were determined using the non-competitive inhibition kinetic model proposed by Takahashi et al. Antifungal activities of TBZ (2-(4'-Thiazolyl)-benzimidazole) against Aspergillus niger were evaluated by this method.
