Natural products have long been a crucial source of, or provided inspiration for new agrochemical discovery.  Naturally occurring 18β-glycyrrhetinic acid shows broad-spectrum bioactivities and is a potential skeleton for novel drug discovery.  To extend the utility of 18β-glycyrrhetinic acid for agricultural uses, a series of novel 18β-glycyrrhetinic acid amide derivatives were prepared and evaluated for their antibacterial potency.  Notably, compound 5k showed good antibacterial activity in vitro against Xanthomonas oryzae pv. oryzae (Xoo, EC₅₀=3.64 mg L^–1), and excellent protective activity (54.68%) against Xoo in vivo.  Compound 5k induced excessive production and accumulation of reactive oxygen species in the tested pathogens, resulting in damaging the bacterial cell envelope.  More interestingly, compound 5k could increase the activities of plant defense enzymes including catalase, superoxide dismutase, peroxidase, and phenylalanine ammonia lyase.  Taken together, these enjoyable results suggested that designed compounds derived from 18β-glycyrrhetinic acid showed potential for controlling intractable plant bacterial diseases by disturbing the balance of the phytopathogen’s redox system and activating the plant defense system

Increasing prolificacy is an important aim in the pig industry.  Regions associated with litter size have been revealed, but detailed molecular mechanisms are unclear.  The Meishan pig is one of the most prolific breeds, with higher prolificacy than the Yorkshire pig, which exhibits high feeding efficiency and lean meat yield.  The ovary is the key organ determining reproductive traits during pregnancy by synthesizing and secreting reproductive hormones essential for conceptus maintenance.  In this comparative multi-omics study of the ovary transcriptome, proteome, and metabolome on day 49 of pregnancy, we aimed to identify genomic, proteomic, and metabolomic differences between the ovaries of Meishan and Yorkshire pigs to reveal potential molecular mechanisms conferring high prolificacy.  Meishan pigs demonstrated general downregulation of steroid biosynthesis and butanoate metabolism in the ovary during mid-pregnancy at both transcriptome and proteome levels but exhibited higher serum cholesterol, estradiol, and progesterone levels than Yorkshire pigs.  We also identified several single-nucleotide polymorphisms in the genes of the steroid hormone pathway associated with litter number, average birth weight, and total litter weight.  Lower biosynthesis rates but elevated serum levels of reproductive hormones during mid- and late pregnancy are essential for the greater prolificacy of Meishan pigs.

Genes involved in chemosensation are essential for odorant-mediated insect behaviors.  Odorant receptors (ORs) bind and respond to pheromones and plant volatiles, regulating insect behaviors such as mating and host-plant selection, while ionotropic receptors (IRs), which are present at lower levels in insects than ORs, influence ion channels, especially in agricultural pests.  Asian corn borer, Ostrinia furnacalis, is the main pest of maize that causes huge economic losses in Asia.  Twenty-one OfurIRs have been identified, but none has been characterized.  In this study, tissue-specific expression profiling, phylogenetic analysis, and electroantennography (EAG) analysis were applied to characterize the evolution, expression, and the potential function of OfurIRs.  It was found that 20 OfurIRs were highly expressed in the antennae, except for OfurIR75p3, whereas 10 and nine OfurIRs were highly expressed in the proboscis and genitalia, respectively, indicating that these OfurIRs were functionally associated with feeding and oviposition.  EAG results showed that seven acids elicited responses in the antennae of O. furnacalis and that 2-oxopentanoic acid displayed a significant female-biased response.  Combined with the phylogenetic analysis, 10 OfurIRs in clade 4 were roughly predicted to be candidate receptors for 2-oxopentanoic acid and other tested acids.  These results provide basic information about OfurIRs and may help advance the knolwedge on the olfactory system of O. furnacalis.