Antioxidant And Antibacterial Function Analysis Of Crocus Sativus Petal Extract

Saffron,also known as Crocus sativus L.,is a plant of the genus Crocus in the Iris family.Saffron has antioxidant,anti-inflammatory and anti-tumor functions,among which the main active components are crocin,crocetin and safranal,which are generally believed to be concentrated in its stigma.The stigma of saffron has an extremely low yield,accounting for 7.4%of the mass of the whole flower.To produce 1 kg of stigma,approximately 15 kg of stigma removal material will be produced.These by-products(mainly flower petals)are generally discarded directly,resulting in a waste of resources,so it is necessary to create new value for the saffron industry through by-product development.In this study,saffron petals were used as materials,and the extraction conditions of saffron petals were optimized by comparing steam distillation,ultrasonic-assisted extraction and organic solvent extraction,and the chemical components of saffron petals were analyzed by GC-MS and LC-MS.The optimized extraction method was used to obtain the saffron petal extract.The antioxidant capacity of the extract was determined by the effect on Celegans and free radical scavenging rate,and the inhibitory effect on Staphylococcus aureus,Bacillus subtilis,Escherichia coli,Salmonella typhi and Bacillus aeruginosa were tested.This study mainly obtained the following results:1.A total of 1060 metabolites in volatile components of saffron petals were determined by full spectrum analysis,including 25 categories such as terpenoids,phenolic acids,flavonoids and polysaccharides.These include safranal and crocetin,the characteristic ingredients of saffron.2.The extraction method of saffron petals was optimized from the aspects of extraction method,extraction solvent and solvent concentration.The results showed that methanol and ethanol were excellent solvents for extracting active components of saffron petals.The active ingredient content of 70%ethanol combined with ultrasonic extraction was the highest,and the contents of crocin Ⅰ and Ⅱ were up to 210.81 μg/g and 88.45 μg/g,respectively.3.The optimized 60%ethanol ultrasonic extract showed a broad spectrum of antibacterial activity against Staphylococcus aureus,Bacillus subtilis,Escherichia coli,Pseudomonas aeruginosa and Salmonella typhi,which were 10.25 mm,18.08 mm,13.33 mm,11.33 mm and 9.08 mm,respectively.At the same time,the IC50 of the extracts against DPPH and ABTS free radicals were 0.56 mg/mL and 2.51 mg/mL,respectively,indicating that the extracts had strong antioxidant activity in vitro.4.Effects of 0.1 mg/mL and 1 mg/mL Saffron flower petal extract on C.elegans:(1)the average life expectancy of C.elegans was increased by 17.30%and 18.67%,respectively;(2)The physiological state of C.elegans was improved with the increase of body bending frequency and head swinging frequency;(3)Antioxidant stress levels increased by 23.3%and 24.4%.In this study,saffron petals were extracted,and the chemical constituents and bioactive functions of the extracts were detected,so as to explore the potential value of saffron petals,in order to provide reference for further comprehensive development and utilization of saffron resources.