Kiwifruit seed oil prevents obesity by regulating inflammation, thermogenesis, and gut microbiota in high-fat diet-induced obese C57BL/6 mice.

Obesity is considered as a chronic disease which seriously affecting people's health and daily life. Kiwifruit (Actinidia chinensis Planch) seed oil (KSO), as a by-product of kiwifruit processing, is rich in fatty acids. Conventional wisdom holds that KSO has many health benefits, but there is no scientific basis. Here, the relieving effects of KSO on obesity and its potential mechanism were investigated in high-fat diet (HFD)-induced C57BL/6 mice. Mice were divided into four groups: ND (normal diet); HFD; L-KSO and H-KSO (HFD supplemented with 1.0 and 3.0 mL/kg·bw of KSO per day, respectively). Results showed that continuous supplementation KSO for 12 weeks significantly decreased bodyweight, inguinal fat tissue weight, blood glucose, and HOMA-IR index and ameliorated serum lipids accumulation (TC, TG, HDL-C, and LDL-C). Relative mRNA expression of inflammatory cytokines (TNF-α, IL-6, IL-1ß, COX-2, and iNOS) was down-regulated and expression of thermogenesis-related genes (PPAR-γ, UCP1, PGC1-α, and PRDM16) was up-regulated in the inguinal fat tissue of KSO treated mice. Principal component analysis showed that the microbial community compositions of four groups were different. KSO supplementation dramatically decreased the Firmicutes-to-Bacteroidetes ratio. Together, our findings demonstrated that long-term supplementation KSO ameliorates obesity by reducing inflammation, adipose thermogenesis and gut microbiota dysbiosis.

Extraction of kiwi seed oil: Soxhlet versus four different non-conventional techniques.

Kiwi seed oil has a nutritionally interesting fatty acid profile, but a rather low oxidative stability, which requires careful extraction procedures and adequate packaging and storage. For these reasons and with the aim to achieve process intensification with shorter extraction time, lower energy consumption and higher yields, four different non-conventional techniques were experimented. Kiwi seeds were extracted in hexane using classic Soxhlet as well as under power ultrasound (US), microwaves (MWs; closed vessel) and MW-integrated Soxhlet. Supercritical CO2 was also employed and compared to the other techniques in term of yield, extraction time, fatty acid profiles and organoleptic properties. All these non-conventional techniques are fast, effective and safe. A sensory evaluation test showed the presence of off-flavours in oil samples extracted by Soxhlet and US, an indicator of partial degradation.

Extracellular matrix of plant callus tissue visualized by ESEM and SEM.

Actinidia deliciosa endosperm-derived callus culture is stable over a long period of culture. This system was used to investigate the ultrastructure of extracellular matrix occurring in morphogenic tissue. Specimens were prepared by different biological techniques (chemical fixation, liquid nitrogen fixation, glycerol substitution, critical-point drying, lyophilization) and observed by scanning electron microscopy (SEM). Fresh and wet samples were analyzed with the use of environmental scanning electron microscopy (ESEM). Extracellular matrix was observed on the surface of cell clusters as a membranous layer or reticulated network, shrunken or wrinkled, depending on the procedure. Generally, shrunken membranous layers with a globular appearance and fibrils were noted after critical-point drying and liquid nitrogen fixation. Smoother surface layers without visible fibrils and showing porosity were typically seen by environmental scanning electron microscopy. Preservation with glycerol substitution caused wrinkled appearance of examined layer. Analysis of fresh samples yielded images closer to their natural state than did critical-point drying or fixation in liquid nitrogen, but it seems best to compare the results of different visualization methods. This is the first report of ESEM observations of plant extracellular matrix and comparison with SEM images from fixed material.