Discovery of zeylenone from Uvaria grandiflora as a potential botanical fungicide

Abstract

BACKGROUND: Botanical pesticides play an important role in organic agricultural practices and are widely used in integrated pest management (IPM). Uvaria grandiflora was mainly reported as traditional medicines and possessed antibacterial, antioxidant, and antiprotozoal activities. Therefore, important biological activities of U. grandiflora may suggest that they have the potential to be used as botanical pesticides.RESULTS: The extract of U. grandiflora exhibited broad-spectrum inhibitory activity toward phytopathogenic fungi and oomycetes, particularly against Colletotrichum musae and Phytophthora capsici, and its secondary metabolite zeylenone also displayed strong antifungal and anti-oomycete activities against phytopathogens. Particularly, half maximal effective concentration (EC 50 ) values of zeylenone against Phytophthora capsici and C. musae were 6.98 and 3.37 ∼g mL −1 , showing better inhibitory effects than those of commercial fungicides (azoxystrobin and osthole). Additionally, the pot experiments showed that the extract of U. grandiflora could effectively control Pseudoperonospora cubensis, Phytophthora infestans, Phytophthora capsici and Podosphaera xanthii. In the field experiment, 5% microemulsion of U. grandiflora extract exhibited 79.72% efficacy against cucumber powdery mildew at 87.5 g ha −1 on the 14th day after two sprayings, which was better than that of 21.5% trifloxystrobin and 21.5% fluopyram SC at 200.9 g ha −1 . Surprisingly, 5% microemulsion of U. grandiflora extract could promote cucumber growth significantly. Furthermore, the action mechanism analysis indicated that zeylenone may damage the cytoderm and affect energy metabolism of Phytophthora capsici.CONCLUSION: It is the first time that the extract of U. grandiflora and zeylenone have been discovered leading to broad application prospects in the development as botanical fungicides.

Antifungal activity of Ligusticum chuanxiong essential oil and its active composition butylidenephthalide against Sclerotium rolfsii

“…Then, the mycelia were sampled and ground into powder under liquid nitrogen for the determination of sugar, lipid and triglyceride content. The content of sugar and lipid in S. rolfsii was determined using DNS method 13 and phosphovanillin method, 41 respectively. The triglyceride content in mycelia was measured using a Triglyceride Assay Kit (Nanjing Jiancheng Bioengineering Research Institute, Nanjing, China).…”

“…Pyruvate content, ATP content and mitochondrial membrane potential are important indicators of mitochondrial functions. 13,42,43 The pyruvate and ATP content of S. rolfsii mycelia after treatments with butylidenephthalide (0, EC 50 and EC 85 ; www.soci.org K Cui et al…”

“…In this context, biogenic pesticides hold significant promise owing to their strong efficacy against phytopathogenic pathogens, lower toxicity and better environmental compatibility compared to chemical pesticides 13 . In recent times, there has been a growing public interest in natural products, including essential oils (EOs) and their extracts because of their potential applications in various fields including pharmaceuticals, food flavoring and preservation, and agriculture.…”

A review of biocontrol agents in controlling late blight of potatoes and tomatoes caused by Phytophthora infestans and the underlying mechanisms

“…The authors speculated that the bioactive peptides are the components of programmed or induced proteolysis of plant proteins, which can realize secondary antimicrobial functions. Potted plant experiments conducted by He et al 94 . indicated that both microemulsion of Uvaria grandiflora extract and its secondary metabolite zeylenone display excellent control efficacies against tomato late blight.…”

Antifungal alkaloids from the branch‐leaves of Clausena lansium Lour. Skeels (Rutaceae)

“…Plants are a potential source of natural compounds with environmentally nonpersistent and low toxicity 20 . Finding antifungal natural compounds from environmentally safe biodegradable plant sources and using them as the lead compounds of new botanical fungicides is one of the feasible strategies to reduce the use of chemical fungicides 21–23 . Many species of plants have been reported to have effects against plant pathogenic fungi, 24 Such as Polygonum cuspidatum (Polygonaceae), 25 Thymus vulgaris (Lamiaceae), 26 Allium sativum (Liliaceae), 27 Cnidium monnieri (Umbelliferae), 28 Syzygium aromaticum (Myrtaceae) 29 and Carpesium macrocephalum (Asteraceae) 30…”