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This work reports the characterisation of caseinolytic and milk-clotting activities of proteases extracted from ripe fruits of Morinda citrifolia L., as a potential of their use in cheese production. Noni puree extract (NPE) was obtained by homogenising the fresh puree in 150 mM NaCl/50 mM sodium phosphate buffer (pH 7.0). The resulting protein concentration was of 0.367 ±â€¯0.006 mg/mL, and an electrophoretic profile of the extract revealed protein bands ranging from 14 to 55 kDa. The proteolytic activity of NPE was higher when the extract had been previously incubated at pH 6.0 (8.859 ±â€¯0.216 U/mg), whereas the optimum caseinolytic activity was observed at 50 °C. Noni puree proteases were strongly (98%) inhibited by iodoacetamide and E-64, suggesting the presence of only cysteine proteases in the crude extract. NPE proteases showed a milk-clotting activity (MCA) of 238.80 ±â€¯5.29 U/mL, a specific milk-clotting activity (SMCA) of 9950.17 ±â€¯220.74 U/mg, and an SMCA/PA ratio of 1124.31 ±â€¯24.94, this last being comparable to those of commercial calf rennet. The cheese manufactured using NPE presented brittle and soft texture, high humidity, and showed sanitary conditions compatible with current Brazilian regulations. The product showed a slightly bitter taste, but still good acceptability, rating between 6 and 7 in the hedonic scale for flavour, texture, and overall acceptance. Lastly, there was 60% of positive purchase intent, demonstrating that noni fruit is a promising source of milk-clotting enzymes for the dairy industry.

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Synthesis of anthraquinones (AQs) involves the shikimate and 2-C-methyl-D-erythritol 4-phosphate pathways. The proline cycle is linked to the pentose phosphate pathway (PPP) to generate NADPH needed in the first steps of this pathway. The effect of two proline analogs, azetidine-2-carboxylic acid (A2C) and thiazolidine-4-carboxylic acid (T4C), were evaluated in Morinda citrifolia suspension cultures. Both analogs gave higher proline accumulation after 6 and 10 days (68 and 179% after 6 days with A2C at 25 and 50 µM, respectively, and 111% with T4C added at 100 µM). Induction of the proline cycle increased the AQ content after 6 days (~40% for 50 µM A2C and 100 µM T4C). Whereas A2C (50 µM) increased only AQ production, T4C also enhanced total phenolics. However, no induction of the PPP was observed with any of the treatments. This pathway therefore does not limit the supply of carbon skeletons to secondary metabolic pathways.

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A Morinda citrifolia cell line was obtained by overexpresion of 1-deoxy-D: -xylulose 5-phosphate synthase (DXS) from Catharanthus roseus, a key enzyme of the metabolic pathway of anthraquinones (AQs). This cell line increased AQs production by about 24% compared to the control cell line. This transgenic cell line which carries dxs cDNA isolated from Catharanthus roseus, was achieved by direct transformation of cell suspension cultures of M. citrifolia using a hypervirulent Agrobacterium tumefaciens strain. The effects of the overexpression of the dxs gene also resulted in increased levels of dxs mRNA transcripts and DXS activity compared to the control cell line. In addition, total phenolics and phenylalanine ammonia-lyase activity were evaluated and were significantly higher in the transgenic line than in controls.

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The numbers of lactic acid bacteria (LAB) and yeasts that were present during a wild forest noni (Morinda coreia Ham) fermentation, the changes in its physico-chemical properties and levels of plant nutrients were investigated. LAB increased rapidly during the first 7 days and were the dominant population until after day 21 when the LAB were declining and the yeasts began to dominate. Identification of the LAB and yeasts to species level showed that the dominant LAB throughout was Lactobacillus plantarum while Lactobacillus pentosus was found but only at day 21. Saccharomyces cerevisiae was the most dominant species of yeast throughout but was slowly replaced by Pichia membranifaciens and then Pichia anomala. Rhodotolura mucilaginosa, an aerobic yeast, was only detected at the beginning of the fermentation process. It is suggested that the Pichia spp. were responsible for consuming lactic acid. After 56 days, the values of pH, acetic acid, ethanol and electrical conductivity in the fermented product were 3.66, 3.34 g L-1, 16.98 g L-1 and 14.47 mS cm-1, respectively. Increased amounts of plant nutrients were present at day 56 mostly derived from the degradation of plant material. At day 56 the amounts were as follows (in mg L-1): N 633, P 1210, K 4356, Ca 693, Mg 536, Mn 7, B 51, Zn 169, and total carbon/total nitrogen ratio (C/N ratio) 18. Based on the seed germination index (GI) of cherry tomato (Lycopersicon esculentum Mill), the extract diluted 256-fold gave the best GI of 157 percent.

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INTRODUCCIÓN: resulta de interés establecer una tecnología propia para la elaboración y el establecimiento de especificaciones de calidad en diversas formulaciones sólidas de extractos secos de Passiflora incarnata L. (pasiflora), Matricaria recutita L. (manzanilla) y Morinda citrifolia L. (noni). OBJETIVOS: realizar los estudios fitoquímicos y analizar parámetros de control de calidad de los extractos secos de Passiflora incarnata L., Matricaria recutita L. y Morinda citrifolia L. MÉTODOS: para el estudio fitoquímico por cromatografía en capa delgada se emplearon técnicas simples, rápidas, selectivas y con equipamiento mínimo para determinados compuestos. Para el análisis de los parámetros de calidad, se aplicaron los ensayos descritos en la Norma Ramal del Ministerio de Salud Pública (NRSP 309). RESULTADOS: se comprobó la presencia de flavonoides, aminoácidos, aminas, azúcares y oligosacaridos en los 3 extractos secos estudiados. En el de M. citrifolia se observó además la presencia de compuestos antraquinónicos y terpenos, mientras que en M. recutita se identificó la presencia de coumarinas. CONCLUSIONES: los resultados obtenidos demostraron que los 3 extractos se encuentran dentro de los límites establecidos para su empleo como principio activo de origen natural.

INTRODUCTION: it is interesting to develop our own technology to work out and to set quality specifications for different solid formulations of Passiflora incarnata L. ((passiflora), Maricaria recutita L. (chamomile) and Morinda citrifolia L. (noni) dry extracts. OBJECTIVES: to conduct phytochemical studies on and to examine the quality control parameters of Passiflora incarnata L. Maricaria recutita L. and Morinda citrifolia L. (noni) dry extracts. METHODS: for the phytochemical study based on thin layer chromatography, quick, simple and selective techniques were used, and minimal amount of equipment was employed for certain compounds. The analysis of the quality control parameters included the assays described in the Branch Standard of the Ministry of Public Health known as NRSP 309. RESULTS: flavonoids, aminoacids, amines, sugars and oligosaccharides were found in the three dry extracts under study. Antraquninone compounds and terpens were observed in the M. citrifolia extract whereas coumarins were present in the M. recutita leaf extract. CONCLUSIONS: the results proved that the three extracts are within the set limits for their use as natural active principle.

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[Structure: see text] Citrifolin A was revised to dehydromethoxygaertneroside (2). Citrifolinoside and yopaaoside A were found to be identical, and their structures were revised to the new structure dehydroepoxymethoxygaertneroside (5). Yopaaoside B was revised to citrifolinoside A (9), and morindacin was revised to borreriagenin (11).

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