Walnuts are rich sources of lipids and polyunsaturated fatty acids and are expected to promote health. There are two Japanese native walnut species: Oni walnut (Juglans ailanthifolia Carr.) and Hime walnut (Juglans subcordiformis Dode.). However, despite the fact that these Japanese native walnuts have long been consumed in local cuisine, their nutritional composition is largely unknown. This study aimed to assess the concentrations of total lipids, and fatty acid composition including polyunsaturated fatty acids, in the kernels of Oni walnut and Hime walnut. In addition, we assessed various aspects related to their nutritional and functional values, by measuring the total protein, amino acids, minerals, and total polyphenols. The concentrations of the measured compounds in the two native species were compared with those in the English walnut (Juglans regia L.), a globally recognized cultivar, and its counterpart cultivated in Japan, Shinano walnut (Juglans regia L.). The results showed that Oni walnut and Hime walnut contained significantly higher protein and minerals and lower lipid content than conventional cultivars. However, both Oni and Hime walnuts contained higher ratios of unsaturated fatty acids in total fatty acids. This study offers novel insights into the nutritional components of Oni and Hime walnuts, contributing to a deeper understanding of their nutritional value and potential applications as unique native walnut species. The findings of this study highlight the relationship between the different types of walnut species and their nutritional composition, and the value of native walnuts used in local cuisine, and will lead to new developments in functional foods from walnut species consumed around the world. It will contribute to the development of functional and processed foods by increasing the production of native walnut species, which are rich in protein, unsaturated fatty acids and minerals and by using them in local cuisines and health-promoting foods.

Purslane (Portulaca oleracea L.) is an annual plant widely distributed throughout the world and has long been used as both food and medicinal plant. In recent years, it has attracted attention as potential functional food and sustainable plant resources. Its tolerance to drought, high temperature, and salt stress has also increased interest in its use as an alternative leafy vegetable under climate change. This review summarizes the compositional diversity of purslane, starting from comparisons between wild and cultivated types. Based on previous reports, the components found in wild and cultivated purslane are compared, and factors that may explain their differences are dis-cussed. Also, their traditional food uses, safety, and current evidence from human studies are introduced. Available evidence suggests that some differences can be observed between wild and cultivated purslane, but these differences are not always consistent. They may also be affected by plant part, growth stage, harvest time, fertilization, growing environment, and processing methods. Overall, comparative studies that consider genetic background, cultivation conditions, plant part, harvest stage, and processing conditions together are important for using purslane as a food and for evaluating its functional properties and safety.

Purslane (Portulaca oleracea L.) is an annual edible plant that is widely distributed and has a long history of use as both food and medicinal plant. It has attracted interest as a source of alpha-linolenic acid, vitamins, minerals, and phenolic compounds, and as an underutilized plant for food applications. This review summarizes the reported compositional diversity of purslane, with particular attention to materials described as wild or cultivated. The available studies differ in cultivar, provenance, plant part, developmental and harvest stage, growth conditions, processing, analytical method, and reporting basis. Consequently, reported differences between wild and cultivated materials should not be interpreted as controlled effects of cultivation status or domestication. Experimental studies nevertheless show that particular nutrient regimes, salinity and light conditions, water treatments, harvest stages, plant parts, and processing methods can modify measured compositional or quality traits. Human intervention studies have used seeds or specific extracts, generally in modest samples and for short periods; their findings should not be generalized to fresh purslane or to purslane as a whole. Replicated common-environment and factorial studies using genetically characterized materials, standardized sampling, and common analytical procedures are needed to estimate plant-material, environmental, and interaction effects. These distinctions are essential for evaluating the nutritional, functional, safety, food-use, and agricultural potential of purslane.