Cottonseed Meal Protein Isolate as a New Source of Alternative Proteins: A Proteomics Perspective

An Empirical Analysis of Sacha Inchi (Plantae: Plukenetia volubilis L.) Seed Proteins and Their Applications in the Food and Biopharmaceutical Industries

Sacha Inchi (Plukenetia volubilis L.) is a plant native in the Amazon rainforest in South America known for its edible seeds, which are rich in lipids, proteins, vitamin E, polyphenols, minerals, and amino acids. Rural communities in developing nations have been using this plant for its health benefits, including as a topical cream for rejuvenating and revitalising skin and as a treatment for muscle pain and rheumatism. Although Sacha Inchi oil has been applied topically to soften skin, treat skin diseases, and heal wounds, its protein-rich seeds have not yet received proper attention for extensive investigation. Proteins in Sacha Inchi seeds are generally known to have antioxidant and antifungal activities and are extensively used nowadays in making protein-rich food alternatives worldwide. Notably, large-scale use of seed proteins has begun in nanoparticle and biofusion technologies related to the human health-benefitting sector. To extract and identify their proteins, the current study examined Sacha Inchi seeds collected from the Malaysian state of Kedah. Our analysis revealed a protein concentration of 73.8 ± 0.002 mg/g of freeze-dried seed flour. Employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) and PEAKS studio analysis, we identified 217 proteins in the seed extract, including 152 with known proteins and 65 unknown proteins. This study marks a significant step towards comprehensively investigating the protein composition of Sacha Inchi seeds and elucidating their potential applications in the food and biopharmaceutical sectors. Our discoveries not only enhance our knowledge of Sacha Inchi's nutritional characteristics but also pave the way for prospective research and innovative advancements in the realms of functional food and health-related domains.

Rumen Microbiota Transplantation Alleviates Gossypol Diet-Induced Reproductive, Liver, and Intestinal Damage in Male Mice

Ruminants exhibit stronger tolerance to gossypol, an anti-nutritional factor, compared to monogastric animals. We transplanted Hu sheep rumen microbiota into male mice to investigate the role of rumen microbiota in animal gossypol tolerance. Thirty specific-pathogen-free (SPF) male C57BL/6 mice were randomly divided into three groups: normal diet (CK group), gossypol diet (FG group), and rumen microbiota transplantation (FMT group, gossypol diet). The pathological changes in the liver and small intestine of the mice, the organ coefficient, and sperm parameters were analyzed. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in the blood and lactate dihydrogen-X (LDH-X) levels in the testicular tissue were also measured. The results showed that body weight, feed intake, sperm concentration, sperm motility, and LDH-X levels in the FMT group increased (p < 0.05) compared with the FG group, while the enzyme activities of ALT, AST, and AST/ALT decreased (p < 0.05). In the FMT group, the injury to liver cells was alleviated, the structure of the small intestine was intact, and the villus height and the ratio of villus height to crypt depth (V/C) were higher than those in the FG group (p < 0.05). And there were no differences in various organ coefficients and sperm deformity rates among the three groups (p > 0.05), but compared with the FG group, mice in the FMT group showed tendencies closer to those in the CK group. Rumen microbiota transplantation relieved the reproductive toxicity and liver damage induced by gossypol in male mice and improved the tolerance of recipient animals to gossypol. Additionally, rumen microbes improved the intestinal structural integrity of recipients.

Paper-based sensing of phytotoxicant gossypol in aqueous media through turn-on visible-light emitting lanthanide-luminescence

Gossypol, a phytotoxicant in cotton-seed oil, has been found to sensitize Tb(III)-luminescence in a supramolecular hydrogel. Based on this observation, a paper-based sensor has been developed to detect gossypol with a limit of detection (LOD) of 2.9 nM. This is the first report of water-based detection with the highest sensitivity involving turn-on time-gated luminescence. This method was also able to sense gossypol in commercial crude cotton-seed oil.

Effects of high-pressure homogenization and ultrasound on the composition, structure, and physicochemical properties of proteins extracted from Nannochloropsis Oceania

This study examined the effects of high-pressure homogenization (HPH) and ultrasonication pre-treatment on the structural and physicochemical properties of proteins extracted from defatted Nannochloropsis Oceania biomass (DNOB). HPH treatment was found to enhance the solubility of protein extracted from DNOB compared to ultrasound, where samples pretreated with three passes (3P) of HPH exhibited lower solubility than two passes (2P). The morphology of extracted samples was visualized by scanning electron microscopy, which HPH pre-treatment, especially with more passes, were able to breakdown DNOB into fragments. Alternatively, more holes were displayed on the surface of the extracts pretreated with ultrasound especially when higher amplitude applied. The particle size of extracts from HPH3P (129.5 µm) significant dropped from HPH2P (314.25 µm), where samples pretreated with ultrasound at 20 % amplitude (US20) also decreased in particle size compared to 40 % amplitude (US40), from 115.25 µm to 78.22 µm. Protein flexibility of DNOB extracts were enhanced by both HPH2P and HPH3P but decreased for ultrasound samples. β-sheets were found to be the most abundant protein secondary structure for all samples, where samples treated with HPH3P contained the highest percentage of β-sheets (72 %) than control, HPH2P, ultrasonication at 20 and 40 % amplitude (52-62 %). The high percentage of β-sheets found in HPH3P sample also contributed to its outstanding emulsifying properties which stood out among all, especially at concentrations over 1 mg/ml. Results obtained from this study helped to direct the application of DNOB extracts as functional food ingredient for future food innovation.

Fractionation and Lability of Phosphorus Species in Cottonseed Meal-Derived Biochars as Influenced by Pyrolysis Temperature

Defatted cottonseed meal (CSM), the residue of cottonseeds after oil extraction, is a major byproduct of the cotton industry. Converting CSM to biochar and utilizing the goods in agricultural and environmental applications may be a value-added, sustainable approach to recycling this byproduct. In this study, raw CSM was transformed into biochar via complete batch slow pyrolysis at 300, 350, 400, 450, 500, 550, and 600 °C. Thermochemical transformation of phosphorus (P) in CSM during pyrolysis was explored. Fractionation, lability, and potential bioavailability of total P (TP) in CSM-derived biochars were evaluated using sequential and batch chemical extraction techniques. The recovery of feed P in biochar was nearly 100% at ≤550 °C and was reduced to <88% at 600 °C. During pyrolysis, the organic P (OP) molecules predominant in CSM were transformed into inorganic P (IP) forms, first to polyphosphates and subsequently to orthophosphates as promoted by a higher pyrolysis temperature. Conversion to biochar greatly reduced the mobility, lability, and bioavailability of TP in CSM. The biochar TP consisted of 9.3-17.9% of readily labile (water-extractable) P, 10.3-24.1% of generally labile (sequentially NaHCO3-extractable) P, 0.5-2.8% of moderately labile (sequentially NaOH-extractable) P, 17.0-53.8% of low labile (sequentially HCl-extractable) P, and 17.8-47.5% of residual (unextractable) P. Mehlich-3 and 1 M HCl were effective batch extraction reagents for estimating the "readily to mid-term" available and the "overall" available P pools of CSM-derived biochars, respectively. The biochar generated at 450 °C exhibited the lowest proportions of readily labile P and residual P compounds, suggesting 450 °C as the optimal pyrolysis temperature to convert CSM to biochar with maximal P bioavailability and minimal runoff risk.

The Effects of Oil Content on the Structural and Textural Properties of Cottonseed Butter/Spread Products

Plant-based butters from nuts and seeds have steadily increased in consumer popularity due to their unique flavors and healthy nutritional properties. Oil content is a critical parameter to measure the proper consistency and stability of plant butter and spread products. Previous work has shown that glandless cottonseed can be used to formulate cottonseed butter products to increase the values of cottonseed. As part of the efforts made in the valorization of cottonseed, this work evaluated the effects of oil content on the microstructural and textural properties of cottonseed butter/spread products. While the oil content in the raw cottonseed kernels was 35% of the kernel biomass, additional cottonseed oil was added to make cottonseed butter products with six oil content levels (i.e., 36, 43, 47, 50, 53, and 57%). The values of three textural parameters, firmness, spreadability, and adhesiveness, decreased rapidly in an exponential mode with the increasing oil content. The particle size population in these butter samples was characterized by similar trimodal distribution, with the majority in the middle mode region with particle sizes around 4.5-10 μm. Higher oil content decreased the butter particle size slightly but increased oil separation during storage. The oxidation stability with a rapid oxygen measurement was gradually reduced from 250 min with 36% oil to 65 min with 57% oil. The results of this work provide information for the further optimization of formulation parameters of cottonseed butter products.

Characterization of the Nonpolar and Polar Extractable Components of Glanded Cottonseed for Its Valorization

Cottonseed is the second major product of cotton (Gossypium spp.) crops after fiber. Thus, the characterization and valorization of cottonseed are important parts of cotton utilization research. In this work, the nonpolar and polar fractions of glanded (Gd) cottonseed were sequentially extracted by 100% hexane and 80% ethanol aqueous solutions and subjected to ¹³C and ¹H nuclear magnetic resonance (NMR) spectroscopy and Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS), respectively. The nonpolar (crude oil) extracts showed the characteristic NMR peak features of edible plant oils with the absence of ω-3 linolenic acid. Quantitative analysis revealed the percentage of polyunsaturated, monounsaturated, and saturated fatty acids as 48.7%, 16.9%, and 34.4%, respectively. Both general unsaturated fatty acid features and some specific olefinic compounds (e.g., oleic, linolenic, and gondonic acids) were found in the nonpolar fraction. In the polar extracts, FT-ICR MS detected 1673 formulas, with approximately 1/3 being potential phenolic compounds. Both the total and phenolic formulas fell mainly in the categories of lipid, peptide-like, carbohydrate, and lignin. A literature search and comparison further identifies some of these formulas as potential bioactive compounds. For example, one compound [2,5-dihydroxy-N'-(2,3,4-trihydroxybenzylidene) benzohydrazide] identified in the polar extracts is likely responsible for the anticancer function observed when used on human breast cancer cell lines. The chemical profile of the polar extracts provides a formulary for the exploration of bioactive component candidates derived from cottonseed for nutritive, health, and medical applications.

Cross-Serological Reaction of Glandless Cottonseed Proteins to Peanut and Tree Nut Allergic IgE

Food allergy is a potentially life-threatening health concern caused by immunoglobulin E (IgE) antibodies that mistakenly recognize normally harmless food proteins as threats. Peanuts and tree nuts contain several seed storage proteins that commonly act as allergens. Glandless cottonseed, lacking the toxic compound gossypol, is a new food source. However, the seed storage proteins in cottonseed may act as allergens. To assess this risk, glandless cottonseed protein extracts were evaluated for IgE binding by peanut and tree nut allergic volunteers. ELISA demonstrated that 25% of 32 samples had significant binding to cottonseed extracts. Immunoblot analysis with pooled sera indicated that IgE recognized a pair of bands migrating at approximately 50 kDa. Excision of these bands and subsequent mass-spectrometric analysis demonstrated peptide matches to cotton C72 and GC72 vicilin and legumin A and B proteins. Further, in silico analysis indicated similarity of the cotton vicilin and legumin proteins to peanut vicilin (Ara h 1) and cashew nut legumin (Ana o 2) IgE-binding epitopes among others. The observations suggest both the cotton vicilin and legumin proteins were recognized by the nut allergic IgE, and they should be considered for future allergen risk assessments evaluating glandless cottonseed protein products.

Plant Proteomic Research 5.0: From Data to Insights

Proteomics offers one of the best approaches for the functional analysis of the genome, generating detailed information that can be integrated with that obtained by other classic and omics approaches [...].