https://doi.org/10.17113/ftb.60.03.22.7456

Fruit Extract Derived from a Mixture of Noni, Pineapple and Mango Capable of Coagulating Milk and Producing Curd with Antidiabetic Activities

Jaya Vejayan^1*, Rupbansraaj Bathmanathan¹, Sharifah Aminah Tuan Said¹, Srikumar Chakravarthi² and Halijah Ibrahim³

¹Faculty of Industrial Sciences & Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300, Gambang, Kuantan, Pahang Darul Makmur, Malaysia

²Faculty of Medicine, Biomedical Sciences and Nursing, MAHSA University, Jalan SP2, Bandar Saujana Putra, 42610 Jenjarom, Selangor, Malaysia

³Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia

Article history:

Received: 2 August 2021

Accepted: 28 April 2022

Key words:

milk coagulation; antidiabetic curd; streptozotocin-induced diabetes; Morinda citrifolia; Mangifera indica; Ananas comosus

Summary:

Research background. Morinda citrifolia L. (noni), Ananas comosus L. cv. Sarawak (pineapple) and Mangifera indica L. cv. Apple (mango) represent fruits capable of coagulating milk, forming a curd. Plant-derived milk coagulants have antidiabetic phytochemicals that enrich the curd. Hence this work evaluated the dual benefits of the fruits in coagulating milk and the antidiabetic activities found in the curd produced by them.

Experimental approach. The three fruits were mixed to form a supercoagulant (a milk coagulant mixture of the extracts at a ratio of 1:1:1), and the milk coagulation time was measured. The milk was coagulated by the supercoagulant, and the fortified curd was tested for its ability to inhibit α-glucosidase and α-amylase. Then, the fortified curd was fed daily to streptozotocin-induced diabetic rats and compared with the untreated diabetic rats and normal rats related to their biochemical markers such as blood glucose level, aspartate aminotransferase, alanine transaminase etc. and histopathology of their liver and kidney tissues.

Results and conclusions. The supercoagulant had a milk coagulation time of (28±3) s at a 50 mg/mL concentration. Its fortified curd inhibited α-glucosidase and α-amylase, with IC₅₀ values of (4.04±0.03) mg/mL and (3.42±0.02) mg/mL, respectively. The average mass of the streptozotocin-induced diabetic rats fed daily with curd formed by the supercoagulant (SC) was (201±10) g on day 20 in comparison to diabetic control rats (DC), (149±16) g. The blood glucose level after fasting for SC was (15±1) mmol/L compared to DC rats, (26±2) mmol/L. Blood tests on SC for aspartate aminotransferase, alanine transaminase, gamma-glutamyl transferase and alkaline phosphatase (liver function tests) levels were shown to be (214±78) U/L, (91±13) U/L, 3 U/L and (510±138) U/L, respectively, while the total protein test and renal function tests showed the levels of albumin, globulin, urea and creatinine to be (37±2) g/L, (30±2) g/L, (11±1) mmol/L and (42±3) µmol/L, respectively. These levels were found to be approximately similar to those of the normal rats on day 20. Furthermore, a histopathological study performed on the liver and kidney of the rats found no apparent damage.

Novelty and scientific contribution. This supercoagulant derived from a mixture of fruits is able to coagulate milk rapidly, and its curd is fortified with safe antidiabetic agents. The supercoagulant potentially useful in producing functional dairy food to prevent diabetes or as supplement for diabetics to control their blood sugar. Such products capable to replace dairy products derived from animal enzymes or add to existing functional dairy products for selection by consumers.