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The tea plant, <i>Camellia sinensis</i> (L.) O. Kuntze is an important crop in the agriculturally based economy of Kenya. Many diseases affect the tea plant but the most prevalent is armillaria root rot caused by the fungus <i>Armillaria mellea</i>. Compounds from the fermentation of <i>Trichoderma</i> species in different media were bioassayed against some selected gram-positive and gram-negative bacteria, fungi including <i>Armillaria mellea</i>, a yeast and a Mucor. Compounds obtained from <i>T. harzianum</i>, and <i>T. longibrachiatum</i> when cultured in various media were investigated individually for in-vitro antifungal and antibacterial activities by agar diffusion technique. Some of the compounds produced definite antifungal and antibacterial activities. 2-Phenylethanol (<b>1</b>) and tyrosol (<b>2</b>) obtained from <i>T. harzianum</i> are reported for the first time from <i>Trichoderma</i> species. The most active metabolite isolated from these strains was 6-n-pentyl-α-pyrone (<b>3</b>), which showed the highest antifungal and antibacterial activity and completely inhibited the growth of <i>Armillaria mellea</i> fungus at a concentration of 200 ppm. Compound <b>4</b> (sorbicillin) exhibited moderate activity against the fungal test organisms.