1a. Objectives (from AD-416):
1. Quantify the compositional and microbial changes of noni juice during the fermentation period. 2. Develop a standard method for processing fermented noni juice.
1b. Approach (from AD-416):
Physiologically mature, ripe noni fruit will be harvested from commercial orchards on the island of Hawaii. Fruit will be washed and placed into sterilized glass jars with sealed lids and allowed to age for 10-14 days at 25°C. A second batch will be aged for up to 30 days. Juice will be pasteurized at 85°C in a water bath, cooled, and frozen. Subsamples of juice will be collected throughout the fermentation process to conduct compositional and microbial analyses. Prominent yeast, bacteria, and fungi will be isolated and identified using standard microbiological techniques. Ascorbic acid, malic acid, lactic acid, and sugar concentrations will be analyzed using high performance liquid chromatography (HPLC). Total antioxidant activity will be determined using a photochemical luminescence method. Collaborators at the University of Hawaii, College of Pharmacy will test samples of noni juice for bioactivity and toxicity in various cell culture assays.
3. Progress Report:
The goal of the Trust Agreement is to quantify the compositional and microbial changes of noni juice during the fermentation period and to develop a standard method for processing fermented noni juice. Noni fruit (Morinda citrifolia) are used to produce fermented juice that often varies in chemical, physical, microbial, and medicinal properties. We completed chemical analyses of noni juice sugars, organic acids, and ethanol concentrations over 28 days of fermentation using liquid chromatography. The results reveal fermentation end-points for standardizing the processing of noni juice. Also, the antifungal properties of pasteurized (85 ºC, 3 min) noni juice exudate were determined in spot-plate bioassays against several fungal plant pathogens of tropical fruit crops. In bioassays of fresh or fermented noni juice, antifungal activity was absent in juice with 5% soluble solids (TSS). However, fermented noni juice with 7% TSS or higher completely inhibited spore germination of five plant fungal pathogens (Lasmenia sp., Colletotrichum acutatum, C. gloeosporioides, Gliocephalotrichum bulbilium, G. simplex). In related research, large volumes of noni juice were prepared for partitioning with n-butanol and ethyl acetate. Previously, our collaborators reported that fermented noni juice demonstrated antitumor activity, and that the n-butanol and ethyl acetate fractions contained active components. The collected partitions were further fractionated into five n-butanol and eight ethyl acetate subfractions to identify specific subfractions with antitumor activity in bioassays and mice models by collaborators. The work in the Trust Agreement will contribute directly to objective 2 of the parent project to develop new or improved postharvest treatments and enhance product value.