Foliar Spray with Pepsin-and Papain-Whey Protein Hydrolysates Promotes the Productivity of Pea Plants Cultivated in Clay Loam Soil

Abstract

Papain and pepsin-hydrolyzed whey protein (PAH and PEH, respectively) were prepared and characterized for its degree of hydrolysis, chemical constituents (amino acid and peptides) and antioxidant activity. A field experiment was conducted at El Salheya El Gedida City, Sharqia, Egypt, during the seasons 2019 and 2020, to investigate the biological action of the foliar spray of PAH and PEH on the growth and yield of pea plants cultivated in a clay loam soil. Foliar application of the papain and pepsin-hydrolyzed whey protein (PAH and PEH, respectively) at 1000 and 2000 mg/L was applied three times after 25, 35 and 45 days from planting. All protein foliar spray treatments had significant positive effects on the uptake of N, P and K, simultaneously increasing the contents of all the photosynthetic pigments (Chlorophyll a, Chlorophyll b and Carotenoids) in a concentration-dependent manner. The most conspicuous increase was seen in Chlorophyll b (105% increase), followed by Carotenoids (91% increase). Generally, the favorable increases caused by the second level of application (2000 mg/L) were nearly 2–3 times that of the low level (1000 mg/L). Pod growth and formation indicators, e.g., no. of pod/plant, pod length and no. of seeds/pod, responded more evidently to the hydrolyzed than the intact form of whey protein treatments. Hydrolyzed whey protein foliar spray treatments achieved significantly higher increases in the global field yield components of Pisum sativum plants than the intact form, where peptic hydrolysates were significantly superior to papain hydrolysate. The treatment PEH (2000 mg/L) can be recommended as the most effective bio-stimulating foliar spray treatment for higher plant productivity when applied 25, 35 and 45 days after planting.

Recent advances in seed coating technologies: transitioning toward sustainable agriculture

“…162 Another key benefit of using PHs is that they can be derived from animal and plant biomass thus promising a sustainable raw material source as well as providing a suitable recycling solution for biological waste. While these have been largely investigated as foliar treatments, 163,164 their use in seed coatings promises targeted delivery and lower drift losses. In a relevant work, Amirkhani et al 165 analyzed the effect of coatings synthesized from a mixture of soy flour, cellulose fiber and diatomaceous earth on broccoli seeds.…”

Enhancing Grain Yield and Nitrogen Accumulation in Wheat Plants Grown under a Mediterranean Arid Environment by Foliar Spray with Papain-Released Whey Peptides

“…One gram of dried material was added to 40 mL of buffer (2.5 M citric acid, 0.048 M norleucine, 10% methanol (v/v), 0.025 percent thiodiglycol (w/v), and 0.01% BRIJ 35 (w/v) adjusted to pH of 2.1) and incubated at 4 • C for 24 h. To precipitate proteins, 2.5 M citric acid, 12% sulphosalicylic acid (w/v), 10% methanol (v/v), 0.025% thiodiglycol (w/v), and 0.01% BRIJ 35 (w/v) were added to an equal volume of sulphosalicylic acid buffer (2.5 M citric acid, 12% sulphosalicylic acid (w/v), and 10% methanol (v/v)). After passing through 0.22 m Millipore filters (Millipore, Watford, UK), the extracts were promptly tested with the reverse-phase HPLC [20].…”

“…Protein hydrolysates are mixtures of free amino acids and polypeptides resulting from chemical and enzymatic hydrolysis of agro-industrial protein by-products derived from plant or animal origins [19]. They are qualified as bio-stimulants capable of promoting plant growth, crop productivity, and alleviating environmental stress impact [20][21][22]. Protein hydrolysates may enhance nutrient uptake and N metabolism through the activation of enzymes involved in their metabolism, thus enhancing the use efficiencies of micro and macronutrients [23].…”

“…Protein hydrolysates can be added as foliar spray or soil drench [25]. The beneficial influences of protein hydrolysates were obtained at a low dose (2 g L −1 ) of application on Pisum sativum L. [20].…”

Effect of Enzyme Type and Hydrolysis Time on Antibacterial and Antioxidant Activity of Whey Protein Hydrolysates

“…On other hand, DPPH-free radical inhibitory activity of cumin protein hydrolysates was highest after 160 min when using pancreatin while reaching maximum activity after 240 min when using alcalase (43). Antibacterial activity of goat whey protein by alcalase treatment is best achieved after 240 min (31), meanwhile, peptic hydrolysates of bovine whey achieved best activity against Listeria ivanovii after 90 min of hydrolysis (52). The main cause behind the variation in the activity at different times may be due to the differentially released peptides and amino acids (12).…”