Changes in curcuminoids and chemical components of turmeric (Curcuma longa L.) under freeze-drying and low-temperature drying methods
FOOD CHEMISTRY
Authors: Chumroenphat, Theeraphan; Somboonwatthanakul, Issaraporn; Saensouk, Surapon; Siriamornpun, Sirithon
Abstract
We investigated how various drying methods affect the chemical components and microstructure of turmeric. We used freeze drying (FD), hot-air drying (HD) at 50 degrees C and sun drying (SD). Compared to all dried samples, fresh turmeric had greater amounts of chemical components (curcuminoids, phenolic acids, flavonoids and amino acids) and greater antioxidant activity (DPPH and FRAP) except for ABTS values. SD caused a severe decline of three major curcuminoids, resulting from UV and light degradation. Curcumin was decreased the most by SD (72%), followed by HD (61%) and FD (55%), respectively. Curcumin degradation to ferulic acid and vanillin was explored by FTIR analysis. The amino acids were decreased by all drying methods. FD was considered to be most suitable for drying turmeric. Microstructure changes were least after freeze drying, but were still evident compared with fresh turmeric.
Protection against Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice by Neferine, A Natural Product from Nelumbo nucifera Gaertn
CELL JOURNAL
Authors: Min, Xiangjing; Guo, Yanling; Zhou, Yishan; Chen, Xiuping
Abstract
Objective: Ulcerative colitis (UC) is a long-lasting inflammatory disease of the colon. Epidemiological studies showed that the prevalence and incidence of UC are increasing worldwide in recent years. Neferine is a natural alkaloid isolated from Nelumbo nucifera Gaertn that exerts a variety of biological activities. This study was designed to evaluate the protective effect of neferine on dextran sulfate sodium (DSS)-induced experimental UC in mice. Materials and Methods: In this experimental study, 4% DSS was used to induce a mice model of UC. Neferine (5 and 10 mg/kg) was administered by intraperitoneal injection (ip). Clinical symptoms and disease activity index (DAI) scores were recorded and calculated. Pathological changes of colon tissues were detected by Hematoxylin and Eosin (H&E) staining. The levels of inflammatory mediators were detected by ELISA kits. Western blotting and immunohistochemical analysis were used for the evaluation of protein expressions. Results: Neferine treatment significantly alleviated DSS-induced UC by inhibiting weight loss, decreasing DAI scores, and alleviating the pathological changes in colon tissues. Furthermore, neferine significantly decreased serum levels of pro-inflammatory cytokines including tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and IL-6 and increased serum levels of anti-inflammatory cytokine IL-10. The increased myeloperoxidase (MPO) activity and nitric oxide (NO) in colon tissues were also inhibited. In addition, neferine significantly down-regulated inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and intercellular cell adhesion molecule-1 (ICAM-1) expression in colon tissues. Conclusion: These results provided evidence that neferine could protect against DSS-induced UC symptoms in an experimental mice model. This effect might be mediated through inhibition of inflammation.