Insights into milk-clotting activity of latex peptidases from Calotropis procera and Cryptostegia grandiflora

Abstract

Latex fractions from Calotropis procera, Cryptostegia grandiflora, Plumeria rubra, and Himatanthus drasticus were assayed in order to prospect for new plant peptidases with milk-clotting activities, for use as rennet alternatives. Only C. procera and C. grandiflora latex fractions exhibited proteolytic and milk-clotting activities, which were not affected by high concentrations of NaCl and CaCl. However, pre-incubation of both samples at 75°C for 10min eliminated completely their activities. Both proteolytic fractions were able to hydrolyze k-casein and to produce peptides of 16kDa, a similar SDS-PAGE profile to commercial chymosin. RP-HPLC and mass spectrometry analyses of the k-casein peptides showed that the peptidases from C. procera or C. grandiflora hydrolyzed k-casein similar to commercial chymosin. The cheeses made with both latex peptidases exhibited yields, dry masses, and soluble proteins similar to cheeses prepared with commercial chymosin. In conclusion, C. procera and C. grandiflora latex peptidases with the ability to coagulate milk can be used as alternatives to commercial animal chymosin in the cheese manufacturing process.

Allergenicity reduction of cow’s milk proteins using latex peptidases

“…Interestingly, C. procera and C. grandiflora latex peptidases did not undergo autolysis and were active even after a 24 h incubation at 37 ºC (Freitas et al, 2016). All these biochemical characteristics strengthen the evidence that peptidases from C. procera, C. grandiflora, and C. papaya present high stabilities and have potential uses in the food industry.…”

“…The presence of certain ions can also be an important element in enzymatic reactions, since they can decrease the activity, or even inactivate enzymes. The calcium ions, abundant in milk, did not affect the proteolytic activity of C. procera, C. grandiflora, and C. papaya, even at 1 M CaCl2 (Freitas et al, 2016). Time can also limit enzymatic reactions catalysed by peptidases, since these enzymes can be inactivated by autodigestion (Oliveira et al, 2018).…”

“…The peptidase content of some latex samples can reach 90% of the total protein (Zare, Moosavi-Movahedi, Salami, Mirzaei, Saboury & Sheibani, 2013). This feature has enabled the use of these enzymes in different biotechnological approaches, such as the dehairing of leather (Lopéz et al, 2017) and milk clotting (Freitas et al, 2016). Accordingly, our hypothesis was that latex peptidases could be efficient molecules for the hydrolysis of proteins in cow's milk, producing hypoallergenic formulas.…”

Milk-clotting properties of plant rennets and their enzymatic, rheological, and sensory role in cheese making: A review

“…This index was sufficiently high to justify the use of this enzyme extract as an appropriate substitute of calf rennet. [65] According to a recent study on plant rennets, [67] Calotropis procera and Cryptostegia grandiflora latex fractions were found to be good sources of milk-clotting proteases. Both coagulant fractions were able to produce similar SDS-PAGE and RP-HPLC profiles of the κ-casein peptides, to those obtained for commercial chymosin.…”

Tropical Fruits of Mango and Noni Having Dual Effects of Coagulating Milk and Enriching the Curds With Micro-Constituents of Medicinal Potential

“…The results revealed that M. citrifolia had the most rapid coagulation time compared to those of M. indica and rennet. The ratio of milk coagulation activity to proteolytic activity (MCA/PA) is a crucial benchmark in determining the peptidase potential to be used as coagulants in cheese industry (Arima et al, 1970;Freitas et al, 2016). In addition, the ratio is regarded as an index to assess possible rennet substitutions (Hashim et al, 2011).…”