Effects of Lactobacillus metabolism on the bio accessibility of phenolics from red pitaya [Hylocereus costaricensis (Weber) Britton & Rose]
Federal University of Paraiba (UFPB)
Department of Food Engineering – Federal University of Paraiba, Campus I, João Pessoa, Paraíba, BRAZIL. CEP 58051-900
Prof. Anoar Abbas
Marciane Magnani
English, Spanish, Portuguese
4 weeks
Cities/Months Jan Feb Mar Apr May Jun Jul Augt Sep Oct Nov Dec
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Type of Research Project
- Basic science
What is the background of the project?
Probiotic lactobacilli have been added to fruit beverages with the purpose of improving health promoting properties. Phenolic compounds (PC) are abundant in red pitaya [Hylocereus costaricensis (Weber) Britton & Rose] and can positively affect the growth and metabolism of lactobacilli. Through decarboxylation, dehydroxylation or cleavage probiotic lactobacilli transform PC into more bio-active and/or available forms. However few is known about the effects of Lactobacillus metabolism on bio accessibility of phenolics from red pitaya-derived products. This project investigates the effects of well-known probiotics on phenolics profile and its bio accessibility in juices and purees of red pitaya.
What is the aim of the project?
This aim of the project is to assess the effects of the metabolism of Lactobacillus acidophilus (LA- 03) and Lactobacillus acidophilus (LA-05), well- known probiotic strains, on phenolic acids and flavonoids profile and their bio accessibility in red pitaya juices and purees.
What techniques and methods are used?
Assays of experimental fermentation of red pitaya based-products with lactobacilli probiotics; Viable cell counts using microdrop cell count procedure of Lactobacillus strains over time (survival curves); Assays with juices and purees fermented and not fermented by Lactobacillus strains under simulated gastrointestinal conditions using a multi-step procedure of continuous simulation; Determination of phenolic acids and flavonoids using high performance liquid chromatography; Statistical analysis (ANOVA and Tukey test) using the STATISTICA 5.1 software.
What is the role of the student?
- The student will observe the practical experiments but will be highly involved in the analysis of the results
- The tasks will be done under supervision
What are the tasks expected to be accomplished by the student?
The student will work on the determination of viability of probiotic strains in fermented red pitaya puree based products using the microdrop viable cell counts procedure during distinct temperatures and storage times. Also, the student with work with a 9-step continuous system simulating the mouth (1 st - step) esophagus-stomach (2 nd - to 7 th -step), duodenum (8 th -step) and ileum (9 th -step) conditions and to prepare methanolic extracts for identification of phenolic acids and flavonoids collected through different digestive steps using high performance liquid chromatography.
Will there be any theoretical teaching provided (preliminary readings, lectures, courses, seminars etc)
Yes, the student will receive the needed theoretical support before to start the practical analysis.
What is expected from the student at the end of the research exchange? What will be the general outcome of the student?
- The student will prepare a poster
What skills are required of the student? Is there any special knowledge or a certain level of studies needed?
Are there any legal limitations in the student’s involvement
Type of students accepted
This project accepts:
- Medical students
- Students in biomedical fields
- DUTRA; R. L. T. ; DANTAS; A. M. ; BATISTA; J. D. F. ; MEIRELES; B. R. L. A. ; CORDEIRO; A. M. T. M. ; MAGNANI; M. ; BORGES; G. C. . Bioaccessibility and antioxidant activity of phenolic compounds in frozen pulps of Brazilian exotic fruits exposed to simulated gastrointestinal conditions. FOOD RESEARCH INTERNATIONAL; v. 100; p. 650-657; 2017.