Determination of Melatonin in Azorean Bovine Milk by RP-HPLC as a Supplement for Sleepless Senior Population

• Autor(a) principal: Paiva, Lisete
• Data de Publicação: 2023
• Outros Autores: Baptista, José
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Texto Completo: http://hdl.handle.net/10400.3/6970
• topic: Bovine; Azores; HPLC; Leite Bovino

ABSTRACT: Melatonin (N-acetil-5-metoxitriptamine) is an indoleamine that is synthesized from the essential amino acid tryptophan via 5-hydroxytryptophan, serotonin and N-acetylserotonin in the vertebrate’s pineal gland, particularly during the nocturnal period (light suppress its biosynthesis) [1,2]. This neurohormone decreases with advancing age, paralleled by a deterioration of normal sleeping pattern and changes in circadian rhythmicity. It is frequently used as a sleep prescribed drug to reduce the symptoms associated to jetleg or shift work [3]. Furthermore, melatonin mediates many neuro-physiological, neuro-endocrinological and behavioral processes, and also participate in several other cellular functions, such as: cancers, Alzheimer`s disease, and depressive syndrome [4]. The objective of this study was the determination of melatonin in Azorean bovine milk (in the range of ppt), in order to make a good use of milk’s melatonin to supplement senior people that, generally, presents low level of this neurohormone, fact that increases with the progression of the ageing process. The results shows that Azorean milk melatonin level change according to the season of the year and also according to the nocturnal or diurnal milked periods, showing an average of 40.2 and 78.9 pg/ mL for diurnal and nocturnal periods, during winter period, respectively, and the values of 13.20 and 28.7 pg/mL for diurnal and nocturnal during summertime, respectively. The results also show that the heating treatment affect the melatonin content in the milk, revealing a decreasing level from the raw (46 pg/mL) to the pasteurized (31 pg/mL) and ultra-pasteurized (decreasing from 27 pg/mL at 120°C to 6.6 pg/mL at 150°C).