Development Of Novel Plant-salt And Preliminary Exploration On Its Biological Activity

Plant-salt,derived from plants grown in high-salt environments,is commonly referred to as biomass salt which containing a variety of macroelement and trace elements.It has a low sodium content that the concentration of NaCl is about 20%.Traditional bamboo salt is produced by roastingsea salt in the fresh bamboo tube at high temperature.Although the salt absorbs a certain amount of ingredients of bamboo tube when roasting,bamboo salt does not belong to the category of plant salt in a strict sense.Our group created a kind of bamboo salt that has better quality using a novel technology of medium-frequency smelting.The bamboo tube was replaced by bamboo-leaf extract(i.e bamboo-leaf flavonoid,BLF)and the sea salt was mixed with BLF.The mixture was melted under high temperature and recrystallized when it be cooled.This manufacturing technique subverts the traditional production processes and offers a possibility to theindustrial production,mechanization,standardization and clean production of bamboo salt.Based on the previous studies by our group,we mixed the non-bamboo plant extracts with sea salt and optimized the process parameters.A series of non?bamboo novel plant-salts(nPS)was created,represented by pine salt and plum saltwith a 90?93%content of NaCl.The physical and chemical characteristics,such as elemental composition,lattice structure,color and taste were analyzed.What's more,the whitening efficiency was evaluated in vitro and research were performed that model animals,high salt induced hypertensive rats,were used to study the dietary intervention by nPS,and all nPS achieved excellent results.The main points are as follows:(1)The creation of a novel plant-salt(nPS).The pine and plum plant extracts(powder)were mixed with sea salt at a certain quality ratio of 1?40%and put into the medium frequency furnace.Then they were heated up to 800?1400? under atmospheric conditions and recrystallized after cooling,which was performed one or more times.By optimizing the process parameters such as theratio of extracts,heating rate,melting temperature and insulation time,new plant functional salts,such as pine salt and plum salt,were obtained with various color,stable performance,high and standardized quality,and special biological effects.(2)Analysis of the physicochemical properties and lattice structure of nPS.The physicochemical properties of nPS were determined by pH,chromatography,conductivity,atomic spectrometer,electronic tongue and electron nose using sea salt and violet bamboo salt(traditional bamboo salt)as a reference.The lattice structure was observed by X-ray diffractometer,scanning mirror,transmission mirror and electron microscope.The results showed that,depending on the process parameters,nPS with different color(pink/purple,blue/green,etc.)presented transparent appearance accompanied by a light odor of sulfur.Compared to sea salt,nPS had smaller size,more abundant element composition and about 100 times increasing of potassium,7 times increasing of calcium,and other beneficial elements(such as magnesium,zinc,phosphorus,etc.)are also significantly increased.Lead content decreased significantly,and other harmful elements(such as barium,thallium,cadmium,antimony,etc.)were not detected.(3)Evaluation of whitening efficacy of nPS in vitro.The diphenolase and monophenol inhibition activities of the tyrosinase were studied in pine salt,plum salt and bamboo salt.Besides,the effect of cell migration,proliferation and intracellular tyrosinase activity of mouse B16 melanoma cell were further explored using arbutin as the positive control.The results showed that the pine salt,bamboo salt and plum salt could significantly(p<0.01)inhibit the activity of tyrosine in vitro in a concentration-dependent manner.The inhibition rate of monophenolase was 97.1%,94.8%,48.0%,respectively,and the inhibition rate of diphenolase was all higher than 92.0%when the concentration of pine,bamboo and plum salt were 5%(w/v aqueous solution,similarly hereinafter).0.5%of nPS solution could not significantly inhibit the growth of B16 cells compared to raw salts,while the lateral migration was inhibited.When the concentration of nPS was increased to 0.75%,their inhibition effects of intracellular tyrosinase activity were better than arbutin at the same concentration,and plum salt showed the most prominent effect.It was shown that nPS has the potential to be developed as whitening agents.(4)Animal experiments on the prevention of hypertension by nPS.28 model SD rats were divided into 7 groups at random.Rats were classified into two categories,one was the control group:regular fodder group(foddered with 0.3%salt content and gavage with pure water)and regular sea salt group(salt-free fodder and gavage with 0.013 g/100 g·bw sea salt solution),and each group had 4 rats with pure water freely and;the other was high salt test group:one sea salt group,3 nPS test groups(pine,bamboo,plum salt)and the positive control(felodipine).Rats of this group took salt-free fodder and were administrated with 0.4 g/100 g·bw sample salt solution(equivalent to 8%salt content).Under the premise of drinking pure water ad lib,the systolic pressure of the high-salt model group at 20 d increased significantly(p<0.01)and accompanying with worse liver,renal and heart muscle impairment(p<0.01),but the systolic blood pressure of rats from three nPS oral intervention groups was significantly lower than that from the raw salt control group,and plum salt had the most significant antihypertensive effect.Furthermore,the urine volume of rats in the bamboo salt group was difference with the original salt group and significantly higher than that of other groups(p<0.01),indicating that it had a diuretic effect.The serum creatine kinase level of the pine salt group was significantly lower than that of the raw salt group(p<0.05),indicating that it had the effect of protecting myocardial cells.In summary,the novel Plan-Salt(nPS)created by new technology had better physicochemical characteristics and unique biological functions beyond the traditional bamboo salt.Their excellent whitening activity promised a good application prospects in the field of daily chemicals(containing personal care products).Specially,the regulation ability on blood pressure of the high salt induced rats may subvert the traditional understanding of "table salt" and play a positive role in the human increasingly hypertension dietary intervention.