Euphopias A–C (1–3), three rearranged jatrophane-type diterpenoids with tricyclo­[8.3.0.02,7]­tridecane (1 and 2) and tetracyclo­[11.3.0.02,10.03,7]­hexadecane (3) cores, were isolated from Euphorbia helioscopia. Comprehensive spectroscopic analyses, quantum-chemical calculations, and X-ray diffractions were used to identify their structures. Compounds 1–3 could significantly inhibit NLRP3 inflammasome activation and block NLRP3 inflammasome-induced pyroptosis. Additionally, a mechanistic study revealed that 2 could ameliorate mitochondria damage, thereby interrupting NLRP3 inflammasome activation.

Antifungal activity of methanol and n-hexane leaf, stem, root and inflorescence extracts (1, 2, 3 and 4% w/v) of three Chenopodium species (family Chenopodiaceae) namely Chenopodium album L., Chenopodium murale L. and Chenopodium ambrosioides L. was investigated against Macrophomina phaseolina (Tassi) G. Goid., a soil-borne fungal plant pathogen that has a broad host range and wide geographical distribution. All the extracts of the three Chenopodium species significantly suppressed the test fungal growth. However, there was marked variation among the various extract treatments. Methanol inflorescence extract of C. album exhibited highest antifungal activity resulting in up to 96% reduction in fungal biomass production. By contrast, methanol leaf extract of the same species exhibited least antifungal activity where 21-44% reduction in fungal biomass was recorded due to various employed extract concentrations. The various methanol extracts of C. murale and C. ambrosioides decreased fungal biomass by 62-90 and 50-84%, respectively. Similarly, various n-hexane extracts of C. album, C. murale and C. ambrosioides reduced fungal biomass by 60-94, 43-90 and 49-86%, respectively.

The tuber dormancy is an important aspect of tuber’s physiological age and begins with tuber initiation. It is largely dependent on genotype, environmental conditions, and tuber age. The group Phureja among diploid potatoes, has a very short or no tuber dormancy while the tubers of Solanum jamesii, a wild potato species, may remain dormant for more than eight years and have the tendency to sprout in favourable conditions. The dormancy breakage in potato is accompanied by many physiological changes such as changes in the ratios of abscisic acid (ABA)/ cytokinin and ABA/ gibberellic acid (GA3), catalase inhibition and accumulation of soluble sugars. These all changes are interlinked and occur in the same time frame. The dormant buds have 77% of their nuclei in the growth phase (G1), compared to only 13% in the preparation phase for mitosis (G2), resulting in slower development of active buds. This paper reviews various factors involved in natural and forced dormancy breakage of potato tuber in relation to their use as seed potatoes immediately after harvesting and implementation of different exogenous dormancy breaking methods like cold pre-treatment, growth regulators, electric current and irradiation to induce sprouting in potatoes.

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