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The irritant potential of four triterpenoids, isolated for the first time from the seeds of Caesalpinia bonducella, identified as alpha-amyrin [12-ursen-3beta-ol], beta-amyrin [12-oleanex-3beta-ol], lupeol [lup-20(29)-en-3beta-ol] and lupeol acetate [lup-20(29)-en-3beta-yl acetate] was investigated by open mouse ear assay, evaluating their ID50 (irritant dose in 50% animals) after acute effects and by irritant units (IU) after chronic effects. Alpha-Amyrin, lupeol acetate and beta-amyrin were the most potent and persistent irritant compounds with red weals of 1.5-2.1 cm diameter areas of the animal skin and with lowest ID50 = 0.078, 0.186 and 0.190mg/10 microl after 1.5, 2.10 and 3.5h, respectively. Their reactions lasted for 24 h with IU = 2.5; 0.312 and 1.25 mg/10 microl, respectively. Lupeol was the least irritant and least persistent compound with ID50 = 0.603 mg/10 microl after 4.5 h. Its reaction subsided before 24 h.

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Irritant and cytotoxic potentiality of six coumarins, isolated for the first time from the roots of Angelica glauca identified as 5,6,7-trimethoxycoumarin, 6-methoxy-7,8-methylenedioxycoumarin, bergapten, decursinol angelate, decursin, and nodakenetin, were investigated. The irritant potential was explored by open mouse ear assay, evaluating their ID(50) after acute and by IU (Irritant units) after chronic effects, while the cytotoxic capability was explored by their LC(50), using brine shrimp (Artemia salina) larvae (nauplii). All the coumarins exhibited well-defined irritancy on mouse's ears, compared with the positive controlled euphorbium reaction and cytotoxic response against brine shrimp larvae, compared with the positive control colchicine. Decursinol angelate and decursin were the most potent and persistent irritant compounds with least ID(50), whose reactions lasted for 48 h. 6-Methoxy-7,8-methylenedioxycoumarin and bergaten revealed an intermediate irritant reactions, while 5,6,7-trimethoxycoumarin and nodakenetin displayed the least irritant and least persistent reactions on mouse ears. Both decursin and decursinol angelate also appeared to be the stronger cytotoxic agents than other coumarins. 5,6,7-trimethoxycoumarin displayed an intermediate cytotoxic behaviour, while other three coumarins, i.e., 6-methoxy-7,8-methylenedioxycoumarin, bergapten, and nodakenetin, exhibited the least cytotoxic capacity against brine shrimp larvae.

To investigate biological control mains against phytopathogenic agent Pseudomonas syringae pv. tomato DC3000, responsible for bacterial speck, tests on the antibacterial activity of six essential oils were carried out. The essential oils, obtained by hydro distillation, was analyzed by gas chromatography (GC). The determination of the antibacterial activity of the essential oils carried out in-vitro using the well diffusion, micro atmosphere methods and the determination of MIC and CMB. Only essential oils of Cedrus atlantica had a negative activity against the bacterial strain. However, the overall results of this study suggested that Mintha pulegium, Thym vulgaris, Eucalyptus globulus essential oils had potential as a bio-pesticide for the control of bacterial speck disease of tomato. genetics and biotechnology (PGMB) [5]. This strain is characterized by the production of an endotoxin (pyoverdine) [10] and by its multiple resistance to antibiotics (rifampicin) [4]. The P. syringae pv. tomato cultures were grown on King's B and LB with rifampicin (50 g/ml) agar plates for strain verification.