The walnut varieties in China are rich, the planting area in the country is wide, and the yield ranks at the forefront of the world Walnut kernel is the most important application part of the walnut fruit An in-depth study found that the by-products of walnut, such as green husk and walnut shell, also have great application potential and are cheap raw materials for the extraction of important medical ingredients and the production of industrial products However, the by-products are often burned or discarded as waste during processing, which not only wastes resources but also causes environmental pollution To realize the high value-added application of the walnut fruit, a deep processing of each part of the walnut should be considered Preliminary processing is the key link before walnuts enter the field of intensive processing and consumption The advanced level of the required technological equipment can help to determine the quality of the walnut products The preliminary processing of walnuts in China is mainly divided into six steps: green husk removal, walnut drying, walnut size classification, walnut shell-breaking, walnut shell–kernel separation, and walnut kernel skin removal This paper starts with a presentation of the importance of each link and the existing bottleneck Then, the paper systematically discusses the analysis of the current situation and the development of devices required for each link The working mechanism of each link type and its influence on the design of a corresponding device are summarized On the basis of the corresponding working mechanism, this study classifies and summarizes the characteristics of the core mechanism of the devices for each preliminary process link; then, it evaluates and analyzes the existing typical mechanical devices according to their types Finally, the influence rule of the various devices for each link in the preliminary processing is analyzed as a means of ensuring high-quality walnuts

Walnut Fruit Processing Equipment: Academic Insights and Perspectives

Aliphatic esters are essential constituents of biologically active compounds and versatile chemical intermediates for the synthesis of drugs. However, their preparation from readily available olefins remains challenging. Here, we report a strategy to access aliphatic esters from olefins through a photocatalyzed alkoxycarbonylation reaction. Alkyloxalyl chlorides, generated in situ from the corresponding alcohols and oxalyl chloride, are engaged as alkoxycarbonyl radical fragments under photoredox catalysis. This transformation tolerates a broad scope of electron-rich and electron-deficient olefins and provides the corresponding β-chloro esters in good yields. Additionally, a formal β-selective alkene alkoxycarbonylation is developed. Moreover, a variety of oxindole-3-acetates and furoindolines are prepared in good to excellent yields. A more concise formal synthesis of (±)-physovenine is accomplished as well. With these strategies, a wide range of natural-product-derived olefins and alkyloxalyl chlorides are also successfully employed.

/pdf/efficient-access-to-aliphatic-esters-by-photocatalyzed-13krzj9bi7.pdf

Efficient access to aliphatic esters by photocatalyzed alkoxycarbonylation of alkenes with alkyloxalyl chlorides.

Photocatalytic Decarboxylative [3 + 2] and [4 + 2] Annulation of Enynals and γ,σ-Unsaturated N-(Acyloxy)phthalimides by NaI/PPh3 Catalysis.

The remote C(sp3)–H functionalization enabled by a radical-mediated 1,5-hydrogen-atom transfer (HAT) process using vinyl azides and 1,4-dihydropyridines as precursors has been described. In this study, 1,4-dihydropyridines can function as 1,2-diradical synthons through sequential homolytic cleavage of an ipso-C–C bond and a β-C(sp3)–H bond. This reaction offers facile access to a diverse range of α-tetralones with excellent stereoselectivity. The utility of the present method is further highlighted by its application to rapid assembly of the tetracyclic scaffold present in furanosteroids as well as the synthesis of aromatic amines.

Transition-metal-free radical relay cyclization of vinyl azides with 1,4-dihydropyridines involving a 1,5-hydrogen-atom transfer: access to α-tetralone scaffolds

Juglans mandshurica Maxim., also known as "Manchurian walnut" (Chinese) and "Onigurumi" (Japanese), is a medicinal plant widely distributed in Western and Central Asia, especially in China. It has been traditionally used to treat cancer, gastric ulcers, diarrhea, dysentery, dermatosis, uterine prolapse, and leukopenia. To date, more than 400 constituents including quinones (e.g. naphthoquinones, anthraquinones, naphthalenones, tetralones), phenolics, flavonoids, triterpenoids, coumarins, lignans, phenylpropanoids, diarylheptanoids, and steroids, were isolated and structurally identified from different plant parts of J. mandshurica. Among them, quinones, phenolics, triterpenoids, and diarylheptanoids, as the major bioactive substances, have been extensively studied and displayed significant bioactivity. Previous studies have demonstrated that J. mandshurica and a few of its active components exhibit a wide range of pharmacologically important properties, such as antitumor, immunomodulatory, anti-inflammatory, neuroprotective, anti-diabetic, antiviral, antimicrobial, and anti-melanogenesis activities. However, many investigations on biological activities were mainly based on crude extracts of this plant, and the major bioactive ingredients responsible for these bioactivities have not been well identified. Further in vitro and in vivo studies on the mechanisms of action of the pure bioactive compounds, and more elaborate toxicity studies as well as clinical studies are needed to ensure safety and effectiveness of the plant for human use. Taken together, the present review will provide some specific useful suggestions guide to further investigations and applications of this plant in the preparation of medicines and functional foods.

/pdf/juglans-mandshurica-maxim-a-review-of-its-traditional-usages-496ptb44ab.pdf

Juglans mandshurica Maxim.: A Review of Its Traditional Usages, Phytochemical Constituents, and Pharmacological Properties.

A new triterpene named klodorol B (1), together with six known compounds, were isolated from the green walnut husks of Juglans mandshurica Maxim. Their structures were determined using spectroscopic methods on the basis of 1D and 2D NMR, and high-resolution electrospray ionization mass spectrometry. The isolated compounds were evaluated for their cytotoxic activities on human gastric carcinoma (BGC-823), human liver cancer (HepG-2) and human lung cancer (A549) cell lines. .

Hong-Juan Song

Papers

A new triterpene from the green walnut husks of Juglans mandshurica Maxim.

Two new tetralone glycosides from the green walnut husks of Juglans mandshurica Maxim

α-Tetralone glycosides from the green walnut husks of Juglans mandshurica Maxim. and their cytotoxic activities

Two new dammarane-type triterpenoids from the green walnut husks of Juglans mandshurica Maxim