A novel synthesis method of medium- and long-chain triglyceride lipids from rubber seed oil catalyzed by enzymatic interesterification and its metabolism mechanism.

Medium- and long-chain triglyceride (MLCT) is a striking structural lipid for the supply of energy and essential fatty free acids (FFAs) in the food field. This study aimed to prepare MLCT by enzymatic interesterification of rubber seed oil (RSO) and medium-chain triglyceride (MCT). Fortunately, the conversion of synthesized MLCT could reach 75.4% by the catalysis of Novozym 40086 (7 wt% to MCT) at a temperature of 40 °C with the substrate mole ratio of 1 : 0.7 (RSO : MCT). The as-synthesized MLCT contained unsaturated fatty acid (USFA, 50.13%) at the sn-2 position and exhibited superior performance on the acid value, peroxide value and iodine value in contrast to grade III soybean oil. Moreover, it exhibited the simultaneous release of LCFAs and MCFAs, extremely facilitating the reduction of body weight gain and control of the level of lipids in the blood. Finally, the preferred hepatic metabolism process of the obtained MLCT was proven to be the main cause of the reduced body weight and improved lipid levels by the in vivo deposition experiments. Therefore, our study suggested that the outstanding performance of the MLCT synthesized by RSO in foods as functional lipids.

The effect of supplementation with rubber seed kernel pellet on in vitro rumen fermentation characteristics and fatty acid profiles in swamp buffalo.

BACKGROUND: Rubber seed kernel is a by-product derived from rubber tree plantations. It is rich in C18 unsaturated fatty acids (UFA) and has the potential to be used as a protein source for ruminant diets. This investigation has been conducted to determine the influence of rubber seed kernel pellet (RUSKEP) supplementation on in vitro rumen fermentation characteristics and fatty acid profiles in swamp buffalo. Using a completely randomized design (CRD) and supplementation of RUSKEP at 0, 2, 4, 6, 8, and 10% dry matter (DM) of substrate. RESULTS: The supplementation with RUSKEP had no effect on gas kinetics, cumulative gas production, or degradability. Ruminal pH decreased linearly (P < 0.01) and ammonia-nitrogen (NH3-N) concentration decreased quadratically (P < 0.01) by RUSKEP supplementation. The proportion of acetate (C2) decreased linearly (P < 0.01), but propionate (C3) and butyrate (C4) increased linearly (P < 0.01), resulting in a decrease in the acetate to propionate ratio (C2:C3) (P < 0.01) by RUSKEP supplementation. With an increasing level of dietary RUSKEP, there was a slight increase in UFA in the rumen by increasing the oleic acid (OA; C18:1 cis-9 + trans-9), linoleic acid (LA; C18:2 cis-9,12 + trans-9,12), and α-linolenic acid (ALA; C18:3 cis-9,12,15) concentrations (P < 0.01). CONCLUSIONS: Adding up to 10% of RUSKEP could improve in vitro rumen fermentation and C18 unsaturated fatty acids, especially ALA, in swamp buffalo.

Comparing the wound healing potential of natural rubber latex serum and F1-protein: An in vivo approach.

Chronic wounds pose significant health concerns. Current treatment options include natural compounds like natural rubber latex (NRL) from Hevea brasiliensis. NRL, particularly the F1 protein fraction, has demonstrated bioactivity, biocompatibility, and angiogenic effects. So far, there is no study comparing F1 protein with total NRL serum, and the necessity of downstream processing remains unknown. Here, we evaluated the angiogenic potential of F1 protein compared to total NRL serum and the need for downstream processing. For that, ion exchange chromatography (DEAE-Sepharose), antioxidant activity, physicochemical characterization, cell culture in McCoy fibroblasts, and wound healing in Balb-C mice were performed. Also, the evaluation of histology and collagen content and the levels of inflammatory mediators were quantified. McCoy fibroblast cell assay showed that F1 protein (0.01 %) and total NRL serum (0.01 %) significantly increased cell proliferation by 47.1 ± 11.3 % and 25.5 ± 2.5 %, respectively. However, the AA of F1 protein (78.9 ± 0.8 %) did not show a significant difference compared to NRL serum (77.0 ± 1.1 %). F1 protein and NRL serum were more effective in wound management in rodents. Histopathological analysis confirmed accelerated healing and advanced tissue repair. Similarly, the F1 protein (0.01 %) increased collagen, showing that this fraction can stimulate the synthesis of collagen by fibroblastic cells. Regarding cytokines production (IL-10, TNF-α, IFN-γ), F1 protein and NRL serum did not exert an impact on the synthesis of these cytokines. Furthermore, we did not observe statistically significant changes in dosages of enzymes (MPO and EPO) among the groups. Nevertheless, Nitric Oxide dosage was reduced drastically when the F1 protein (0.01 %) protein was applied topically. These findings contribute to the understanding of F1 protein and NRL serum properties and provide insights into cost-effectiveness and practical applications in medicine and biotechnology. Therefore, further research is needed to assess the economic feasibility of downstream processing for NRL-based herbal medicine derived from Hevea brasiliensis.

Interactions of REF1 and SRPP1 rubber particle proteins from Hevea brasiliensis with synthetic phospholipids: Effect of charge and size of lipid headgroup.

According to the fatty acid and headgroup compositions of the phospholipids (PL) from Hevea brasiliensis latex, three synthetic PL were selected (i.e. POPA: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphate POPC: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and POPG: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol) to investigate the effect of PL headgroup on the interactions with two major proteins of Hevea latex, i.e. Rubber Elongation Factor (REF1) and Small Rubber Particle Protein (SRPP1). Protein/lipid interactions were screened using two models (lipid vesicles in solution or lipid monolayers at air/liquid interface). Calcein leakage, surface pressure, ellipsometry, microscopy and spectroscopy revealed that both REF1 and SRPP1 displayed stronger interactions with anionic POPA and POPG, as compared to zwitterionic POPC. A particular behavior of REF1 was observed when interacting with POPA monolayers (i.e. aggregation + modification of secondary structure from α-helices to ß-sheets, characteristic of its amyloid aggregated form), which might be involved in the irreversible coagulation mechanism of Hevea rubber particles.

Peptidomic Analysis and Antimicrobial Activity of Serum Peptide from Hevea brasiliensis Clone BPM24.

BACKGROUND: Hevea brasiliensis is severely affected by the fungal disease caused by Phytophthora spp. Significant loss of rubber yield is widespread and extensive use of chemical fungicides has resulted in health and environmental problems. OBJECTIVE: This work aims to extract and identify the latex serum peptides from a disease tolerant clone of H. brasiliensis, and study the inhibitory efficacy against pathogenic bacteria and fungi. METHODS: Serum peptides were extracted from H. brasiliensis BPM24 using mixed lysis solution. Low molecular weight peptides were screened and fractionated by solid-phase extraction and then identified by tandem mass spectrometry. Total and fractionated serum peptides were assayed for bacterial and fungal inhibition using broth microdilution and poisoned food methods. An inhibitory control study in the greenhouse was also performed using susceptible clones for pre and postinfection with Phytophthora spp. RESULTS: Forty-three serum peptide sequences were successfully identified. Thirty-four peptides matched with the proteins associated with plant defense response signaling, host resistance, and adverse environmental factors. The inhibitory study of total serum peptides demonstrated antibacterial and anti-fungal properties. The greenhouse study exhibited disease inhibitory efficacy of 60% for the treatment of Phytophthora spp. in post-infected plants and 80% for pre-treated samples. CONCLUSION: Latex serum peptides from disease tolerant H. brasiliensis revealed several proteins and peptides associated with plant defense and disease resistance. The peptides play a vital role for defense against bacteria and fungi pathogens, including Phytophthora spp. Enhanced disease protection can be obtained when the extracted peptides were applied to the susceptible plants before exposure to the fungi. These findings provided an insight and may pave the way for the development of biocontrol peptides from natural resources.

Isolation and Identification of Secondary Metabolites Produced by Phytopathogenic Fungus Corynespora cassiicola from Hevea brasiliensis.

The secondary metabolites of the phytopathogenic fungus Corynespora cassiicola CC01 from Hevea brasiliensis were investigated. As a result, two new compounds, 5-acetyl-7-hydroxy-6- methoxybenzofuran-2(3H)-one (1) and (S)-2-(2,3-dihydrofuro [3,2-c]pyridin-2-yl)propan-2-ol (2), together with seven known compounds, 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (3), 3,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one (4), curvulin acid (5), 2-methyl-5-carboxymethyl- 7-hydroxychromone (6), tyrosol (7), p-hydroxybenzoic acid (8) and cerevisterol (9), were isolated from the fermentation extract by comprehensive silica gel, reverse phase silica gel, Sephadex-LH20 column chromatography and high-performance liquid chromatography (HPLC). The structures of these compounds were identified by using high-resolution electrospray mass spectrometry (HRESIMS), nuclear magnetic resonance spectroscopy (NMR), optical rotation, ultraviolet and infrared spectroscopy techniques and a comparison of NMR data with those reported in the literature. Compounds 1 and 2 were new compounds, and compounds 3-9 were discovered from this phytopathogenic fungus for the first time. Compounds 1-9 were tested for phytotoxicity against the fresh tender leaf of Hevea brasiliensis, and the results show that none of them were phytotoxic. Additionally, these compounds were subjected to an antimicrobial assay against three bacteria (E. coli, methicillin-resistant Staphylococcus aureus and Micrococcus luteus), but they showed no activity.

Simultaneous quantification of volatile fatty acids and nonvolatile organic acids in Hevea brasiliensis latex.

The current method used in latex industries to determine the volatile fatty acids contents of Hevea brasiliensis latex is steam distillation. However, the accuracy of the method has been debated for some time. We assessed the accuracy of the method and developed a new, more reliable high-performance liquid chromatographic method of determining acids in latex. The volatile fatty acids (formic, acetic, propionic, butyric, and valeric acids) and nonvolatile organic acids (oxalic, malic, lactic, citric, and succinic acids) in latex are directly determined simultaneously for the first time with high sensitivity and without losses during sample preparation. To avoid errors from derivatization, an acid-resistant Prevail HPLC column and a gradient mobile phase of 25 mM potassium dihydrogen phosphate (pH 2.5) and acetonitrile were employed. Under optimum conditions, the calibrations of both types of acids demonstrated satisfactory correlation coefficients of  ≥0.990, with limits of detection ranging from 0.02 to 395 mM. The developed method demonstrated the profiles of acids in field and concentrated latex of the same batch. Moreover, the evolution of the profiles of all studied acids in both types of latex during a 3-month period was also revealed.

In vitro antioxidant extracts evaluation from the residue of the Hevea brasiliensis seed.

The antioxidants used in the food industry are essential to inhibit the formation of free radicals, preserving the existing properties in the different matrices. However, the insecurity of the synthetic antioxidants regarding human health propels search for natural substrates with potential antioxidant activity as an alternative to synthetic compounds. In this way, the work had as objective obtaining extracts from the seed pomace of the Hevea brasiliensis (rubber tree), relating the contents of flavonoids and total phenols in the application as an antioxidant. The methodology consisted of the extraction using four solvents, varying extractive methods, time, and seed concentrations. The antioxidant activity in vitro was evaluated by capturing the DPPH (2,2-diphenyl-1-picryl-hydrazil) radical. The optimized results demonstrate that the aqueous extracts produced in the Soxhlet in the concentrations of 85 g L-1 and retention time of 4 h reached 37.73 ± 1.69% in the antioxidant tests of the free radical DPPH capture, 1405.15 mg EAC 100 g-1 in the quantification of phenolic compounds and 223.34 mg 100 g-1 of total flavonoids. Thus, this work may contribute to the realization of studies and future research for characterization and identification concerning which phenolic compounds and flavonoids attribute the antioxidant characteristic to the extracts produced, enabling the discovery of products with high added value in the production chain. In addition, because the water used as a solvent showed greater antioxidant potential between the extracts, the non-toxic and environmentally friendly character is highlighted, allowing a wide variety of applications in the food industry.

Differential Analysis of Mycelial Proteins and Metabolites From Rigidoporus Microporus During In Vitro Interaction With Hevea Brasiliensis.

Rigidoporus microporus is the fungus accountable for the white root rot disease that is detrimental to the rubber tree, Hevea brasiliensis. The pathogenicity mechanism of R. microporus and the identity of the fungal proteins and metabolites involved during the infection process remain unclear. In this study, the protein and metabolite profiles of two R. microporus isolates, Segamat (SEG) and Ayer Molek (AM), were investigated during an in vitro interaction with H. brasiliensis. The isolates were used to inoculate H. brasiliensis clone RRIM 2025, and mycelia adhering to the roots of the plant were collected for analysis. Transmission electron microscope (TEM) images acquired confirms the hyphae attachment and colonization of the mycelia on the root of the H. brasiliensis clones after 4 days of inoculation. The protein samples were subjected to 2-DE analysis and analyzed using MALDI-ToF MS/MS, while the metabolites were extracted using methanol and analyzed using LC/MS-QTOF. Based on the differential analyses, upregulation of proteins that are essential for fungal evolution such as malate dehydrogenase, fructose 1,6-biphosphate aldolase, and glyceraldehyde-3-phosphate dehydrogenase hints an indirect role in fungal pathogenicity, while metabolomic analysis suggests an increase in acidic compounds which may lead to increased cell wall degrading enzyme activity. Bioinformatics analyses revealed that the carbohydrate and amino acid metabolisms were prominently affected in response to the fungal pathogenicity. In addition to that, other pathways that were significantly affected include "Protein Ubiquitination Pathway," Unfolded Protein Response," "HIFα Signaling," and "Sirtuin Signaling Pathway." The identification of responsive proteins and metabolites from this study promotes a better understanding of mechanisms underlying R. microporus pathogenesis and provides a list of potential biological markers for early recognition of the white root rot disease.

Natural latex serum: characterization and biocompatibility assessment using Galleria mellonella as an alternative in vivo model.

Natural latex serum (NLS) is one of the natural rubber latex fractions from Hevea brasiliensis tree, which is formed by centrifuged serum and is composed of proteins, acids, nucleotides, salts and carbohydrates. The proteins present in NLS have demonstrated several interesting biological properties, including angiogenic, healing, osteogenic, anti-inflammatory, antimicrobial, in addition to inducing neovascularization, bone formation and osseointegration. Thus, we proposed to characterize NLS by physicochemical techniques and to investigate the biocompatibility by toxicological assays and safety test in Galleria mellonella. Infrared spectrum showed vibrational bands characteristic of amide I, II and III that are linked to the protein content, which was confirmed by the High Performance Liquid Chromatography profile and by the Electrophoresis analysis. This material did not exhibit hemolytic (rate <0.5%) and cytotoxic effects (viability >70%) and was able to enhance the proliferation of fibroblasts (>600%) after 3 days. The pronounced proliferative effect observed in fibroblast cells can be explained by the presence of the fibroblast growth factor (FGF) like protein revealed by the Western blot test. Moreover, NLS did not provoke toxic effects (survival ∼ 80%) on the G. mellonella model, indicating that it is a biocompatible and safe material.