Acaricidal and Repellent Activity of Terpenoids from Seaweeds Collected in Pernambuco, Brazil

Abstract

n-Hexane and dichloromethane extracts obtained from Laurencia dentroidea (Rhodophyta) and Canistrocarpus cervicornis (Phaeophyta) were investigated for their acaricidal and repellent properties against Tetranychus urticae under laboratory conditions. The two extracts displayed moderate toxicity and good repellent proprieties, and were significantly more toxic (36-fold) than the positive control (eugenol), whereas eugenol was tenfold more repellent than either seaweed extract. The sesquiterpenoid elatol (1) was isolated from L. dentroidea and the diterpenoid seco-dolastane (4 R,9 S,14 S)-4α-acetoxy-9β,14α-dihydroxydolast-1(15),7-diene (2) from C. cervicornis, the chemical structures of which were characterized by NMR spectroscopic data (1H and 13C) and by comparison with literature data. These compounds exhibited moderate toxicity, but a high degree of repellent activity against T. urticae. The findings suggest that marine natural products, specifically terpenes, can be employed for the development of new pesticides and become prototype agrochemical agents.

The Acaricidal Activity of Venom from the Jellyfish Nemopilema nomurai against the Carmine Spider Mite Tetranychus cinnabarinus

“…Gray, Clerodendrum inerme (L.) Gaertn, Hibiscustiliaceus L., and Lumnitzera racemosa Willd were 1.84, 2.88, 2.92, 4.93, and 6.57 g/L, respectively [ 23 ]. However, the extracts of n -hexane and dichloromethane from Laurencia dentroidea (Rhodophyta) and Canistrocarpus cervicornis (Phaeophyta) had high acaricidal activities against Tetranychus urticae and their LC 50 -values were 0.05 and 0.07 μg/cm 2 , respectively [ 24 ].…”

Progress in the Chemistry of Organic Natural Products 102

“…Conversely, interaction with PKCβII is critical for the activation of neutrophils involved in the immunostimulating activity [133]. Ingenol-3-angelate (5) shows an impressive potential to be used as a systemic anticancer agent, especially against leukemia [172], but little information exists on its systemic toxicity and therapeutic window, and similar considerations apply for its use as HIV-1 latency-reversal agent [173]. Ingenol-3-angelate (5) shows an impressive potential to be used as a systemic anticancer agent, especially against leukemia [172], but little information exists on its systemic toxicity and therapeutic window, and similar considerations apply for its use as HIV-1 latency-reversal agent [173].…”

“…The Laurencia Paradox: An Endless Source of Chemodiversity Elatol L. cartilaginea [142], L. chondrioides [157], L. decumbens [160], L. dendroidea [172,173], L. elata [174 a,c,d ], L. majuscula [118,127,128,162,165], L. mariannensis [74], L. microcladia [175], L. obtusa [102,124,129,131,132], L. pacifica [30], L. rigida [81], L. scoparia [102], L. similis [176], Laurencia sp. [165,177], A. dactylomela [50,86,118,135,156,178], A. parvula [166] (continued) Prepacifenol epoxide L. composita [31,69], L. johnstonii [190 a,d , 191], L. nidifica [95], L. okamurai [99,192], Laurencia sp.…”

“…Elatol (59) has also displayed larvicidal activity against the dengue mosquito (Aedes aegypti) [883]. Furthermore, 59, while moderately toxic, showed a high degree of repellent activity against the spider mite Tetranychus urticae in laboratory experiments [173].…”