Sechium Edule Research Articles

EDIBLE COATINGS BASED ON BEESWAX AND SHELLAC EFFECTIVELY PRESERVE CHAYOTE (Sechium edule (Jacq.) Sw. var. virens levis) FRUITS DURING STORAGE

Edible coatings are used to maintain overall quality and extend the shelf-life of fruit after harvest. The objective of this research was to evaluate the effect of edible coatings based on beeswax and shellac on the postharvest quality of fresh chayote [Sechium edule (Jacq.) Sw. var. virens levis] stored for 0, 8, 16, 24, and 32 days at 7 °C. The experiment was conducted with a completely randomized design with mixed effects and three replicates. Physicochemical analyses were carried out for color, texture, acidity, pH, weight loss, and CO2 concentration. The applied coatings stabilized the physicochemical properties and reduced the weight loss percentage (1.8 to 3.4 %) of the chayotes during the storage period without creating an adverse effect compared to the control (4.1 %). The most effective coating (treatment 6) had the highest concentration of beeswax and the lowest concentration of shellac, forming an effective barrier against gases and water vapor.

Sonophotopythochemical Functionalization of Graphene Oxide - Al - Zn Bimetal Nanocomposite for Corrosion Inhibition

The corrosion performance of steel in the marine environment has been a primary concern of engineers and garnered significant interest due to its industrial significance. To address this concern, the incorporation of green corrosion inhibitors as coating materials in mild steel has been extensively studied recently. This paper explores the synthesis of graphene doped with bimetal aluminum-zinc (GO-Al-Zn) nanocomposites via sonophoto-phytochemical functionalization using Chayote (Sechium edule) leaf extract as the doping agent to produce a corrosion inhibitor. The synthesized nanocomposites were characterized using FTIR, SEM-EDS, XRD, and TEM. The optimal nanocomposite, with a 55% Al - 45% Zn ratio, demonstrated successful bio-reduction, good dispersion, reduced particle size, and a rhombohedral crystal structure. When incorporated into an epoxy coating and applied to mild steel, the GO - 55% Al - 45% Zn coating achieved a high corrosion inhibition efficiency of 98.06% (gravimetric method) and 98.45% (electrochemical method) in 3.5 wt% NaCl solution. This study highlights the promising potential of GO - 55% Al - 45% Zn nanocomposite as an eco-friendly corrosion inhibitor. Future research should explore optimizing the functionalization process and exploring long-term environmental stability.

Metabolomic analyses during chayote (Sechium edule var. virens levis) seed germination under the influence of growth regulators

The fruit of chayote (Sechium edule) has a recalcitrant seed, as a consequence, viviparism (seed germination inside the fruit) occurs in the first 13 days after harvest. However, at the moment no phytohormone–dependent metabolic changes have been described that would allow us to understand the hormonal relationship during germination. Untargeted and targeted metabolomic analyses were performed on chayote seed treated with plant growth regulators, evaluated in fruits at 7 and 10 days after harvest. Exogenous application of 2–chloroethylphosphonic acid (ethylene releaser) and gibberellic acid3 accelerated germination and viviparism, while auxins and abscisic acid delayed them. Metabolic pathways and possible key metabolites regulating germination were identified, including ethylene, gibberellins, auxins and abscisic acid. This study suggests a likely hormone interaction model during chayote seed germination.

Cross-environmental cycling of antimicrobial resistance in agricultural areas fertilized with poultry litter: A one health approach

Poultry litter, commonly used as an organic fertilizer, can contain antimicrobial residues, resistant bacteria, and/or antimicrobial resistance genes. After application to soil, these contaminants can reach crops and be transported to aquatic systems through leaching and runoff. Once in water bodies, they can return to soil and crops through irrigation, establishing a cycle that promotes the selection, spread and persistence of antimicrobial resistance. To investigate the hypothesis of a cyclical event, samples of poultry litter, cultivable soil fertilized with this organic residue, rhizosphere soil from Sechium edule (chayote), water, and sediments from irrigation ponds were collected across two agricultural and poultry-producing areas during the dry and rainy seasons. Clinically significant bacteria, especially bacteria belonging to the Enterobacteriaceae family, were isolated. Fifty-three strains exhibited one or more antimicrobial resistance genes, as detected by PCR amplification, including those conferring resistance to sulfonamides (sul1 and sul2), fluoroquinolones (qnrB, qnrA, and qnrS), and β-lactams (blaGES, blaTEM, blaSHV, blaCTX-M-1/2,blaCTX-M-8, and blaCTX-M-14). Genes encoding integrases related to class-1 and 2 integrons (intI1 and intI2) were also observed. A rare occurrence of the blaGES gene was observed in Stenotrophomonas sp. and Brevundimonas sp. Strains of Escherichia sp. were multidrug resistant. Sequencing of the 16S rRNA encoding gene indicated unique operational taxonomic units (OTUs) originating from poultry litter and found in the soil, rhizosphere, water, and sediment, highlighting the dissemination of this material across agricultural substrates. These findings strongly suggest the spread of antimicrobial-resistant bacteria in agricultural environments, posing potential risks to both human and animal health.

Development, Soil Biodegradation, and Kinetics Evaluation of Starch-Based Bioplastic from Sechium edule and Phaseoulus vulgaris

Development, Soil Biodegradation, and Kinetics Evaluation of Starch-Based Bioplastic from Sechium edule and Phaseoulus vulgaris

EVALUATION OF THE MORPHOBIOLOGICAL AND PRODUCTIVE INDICATORS OF CHAYOTE (Sechium edule L) IN THE REGION OF MYZEQE, LIBOFSHË, FIER

Prickly potato - Chayote (Sechium edule L) is an exotic plant that grows and is cultivated in Costa Rica. It has been brought to Albania since 2004 and has been studied several times in different areas, mainly in the warm zone. It is a plant that has many synonyms and uses. Sometimes it is called prickly eggplant or prickly gourd and in some places it is called Kayota. The fruit grows above the ground and the plant develops as a pergola with long shoots. The fruit is used cooked in different forms: fried, dish, and or casserole. The leaves are used to make various pies and it is very tasty, especially when cooked with milk. The fruits are planted in March by placing them in the soil and covering them with 5-8 cm. During the vegetation, measurements of biometric and productive indicators were made: Number of shoots/plant, length of shoots/plant (sum), longest shoot, shortest shoot, number of leaves/plant, leaf color, flower color, the shape of the leaf, the shape of the tuber, the color of the skin of the tuber, the color of the tuber pulp, the placement of the buds on the tuber, yield/plant (kg/plant), number of tubers/plant, average tuber weight (kg), the weight of the largest tuber (kg), the weight of the smallest tuber (kg), yield kv/ha. The fruits were chemically analyzed to determine the main chemical indicators: the content of starch and the most important chemical elements.

Biotransformation of Cinnamic Acid, Cinnamaldehyde, Furfural and Epoxidation of Cyclohexene by Plant Catalase

Background: Epoxides are widely useful in various fields such as pharmaceuticals, pesticides, cosmetics, polymer synthesis, fragrance compounds, and food additives. However, the synthesis of epoxides involves heavy metal catalysts and toxic, unstable organic catalysts which causes serious environmental and safety concerns. In recent years, biocatalysts have received a great deal of interest in the synthesis of olefin-derived epoxides due to their mild reaction conditions, environmental friendliness, good selectivity, and sustainability. This study focuses on catalases as a biocatalyst for potential epoxidation reactions of olefins. Objective:: To determine the possibility of using biocatalyst catalase from a novel source Sechium edule (squash) for epoxidation of olefins in the presence of H2O2. Methods: UV-Vis spectrophotometer was used to monitor the formation of epoxide from substrates- cyclohexene, cinnamic acid, cinnamaldehyde, furfural in acetonitrile solvent and a suitable aliquot of the enzyme solution in the presence of H2O2. The products formed were analyzed using FTIR and GC-MS. For the immobilized enzyme, chitosan beads activated with TPP were used in place of the enzyme and a similar procedure was followed for the analysis. Results: Four different olefin substrates (cyclohexene, cinnamic acid, cinnamaldehyde, and furfural) were selected to study the catalysis reaction of epoxidation by the catalase enzyme. The course of the epoxidation was monitored by UV-Vis, FTIR, and GC-MS methods. However, under optimized reaction conditions and spectral analysis, further confirmed by GC-MS, data showed only epoxide formation from cyclohexene. CAT completely catalyzed other olefins like furfural, cinnamic acid, and cinnamaldehyde into its degraded products biochemically. Therefore, cyclohexene was selected for further immobilization studies and the identified metabolites of olefins and their degradation mechanism. Major biodegradation products of cinnamic acid were found to be styrene( m/z 104.0) and benzaldehyde(m/z 105.0). GC-MS data of biotransformation of cinnamaldehyde, identified 2,4 dimethyl benzaldehyde(m/z 133) as the main product. The catalytic biotransformation of furfural investigated by GC-MS data identified 2,5 dimethyl benzaldehyde (m/z 133), dodecanol (m/z 181) and Pentanoic acid, 5 hydroxy, 2,4 dibutyl phenyl ester(m/z 306) as the major product. Three major oxidized products were detected in GC-MS data from the epoxidation of cyclohexene viz., cyclohexane diol(m/z 116), cyclohexene epoxide-1-ol(m/z 110), cyclohexene epoxide-1-one(m/z 110). Conclusion: In this investigation, catalase purified from Sechium edule(squash) was developed as an efficient catalytic tool for the biotransformation of olefins and selective epoxidation of cyclohexene. Under optimized conditions, the experimental results revealed the main products found in cinnamaldehyde as benzaldehyde (m/z 133.0) and cinnamic acid as benzaldehyde (m/z 133), styrene (m/z 104.0) and benzoic acid (m/z 122.0), while the data from furfural oxidation could not be justified from previous studies. The optimal concentration of CH3CN solvent for cyclohexene epoxidation was found to be 4 mM. Enzymatic characterization of free and immobilized catalase on chitosan was investigated using cyclohexene as a variable substrate and found to be 0.017 mM, 83.33 μmol/min for Km and Vmax values, pH 6.8 and 30˚C for free CAT and 0.03 mM, 200 μmol/min, pH 7.6 and 35˚C for immobilized one. Immobilization increases the thermal stability of the CAT and changes the pH to alkalinity. The possible oxidation of cyclohexene was deduced as the radical chain mechanism for the generation of epoxide with the key products obtained as cyclohexane diol(m/z 116), cyclohexene epoxide-1-ol(m/z 110) and cyclohexene epoxide-1-one(m/z 110). The reusability of the biocatalytic tool opens up the opportunity to reduce the cost of various catalytic reactions. Further studies can focus on the separation and advancement of epoxide yields, improved immobilization strategy for maximum repetitive cycles, and chemo-enzymatic epoxidation on biological olefins.

Evaluation of the Antigenotoxic Potential of Two Types of Chayote (Sechium edule) Juices.

Sechium edule (Jacq.) Swartz is a perennial herbaceous climbing plant with tendrils and tuberous roots belonging to the Cucurbitaceae family. Its fruits ("chayote"), stems, roots, and leaves are edible and are commonly ingested by humans. It has shown medicinal properties attributed to its bioactive compounds (vitamins, phenolic acids, flavonoids, carotenoids, triterpenoids, polyphenolic compounds, phytosterols, and cucurbitacins), which together have been associated with the control and prevention of chronic and infectious diseases, highlighting its antibacterial, anti-cardiovascular/antihypertensive, antiepileptic, anti-inflammatory, hepatoprotective, antiproliferative, and antioxidant activities. The objective of the study was to determine the antigenotoxic potential of two types of fresh chayote juice (filtered (FChJ) and unfiltered (UFChJ)) against DNA damage produced by benzo[a]pyrene (B[a]P) using an in vivo mouse peripheral blood micronucleus assay (MN). The juices were consumed freely for 2 weeks. A negative control, a control group of each juice, a positive batch [B[a]P], and two combined batches (B[a]P plus FChJ or UFChJ) were included. Blood smears were stained and observed under a microscope to quantify the number of micronucleated normochromic erythrocytes (MNNEs). The results indicate: (a) B[a]P increased the frequency of MNNEs and reduced the rate of PEs; and (b) no juice produced toxic effects or induced MN. On the contrary, both juices were genoprotective. However, the most significant effect was presented by UFChJ at the end of the experiment (70%). It is suggested that UFChJ has a greater amount of fiber and/or phytochemicals that favor the therapeutic effect. Possibly, the genoprotection is also related to its antioxidant capacity.

High-quality reference genome decoding and population evolution analysis of prickly Sechium edule

Sechium edule (chayote) is an important vegetable crop belonging to the Cucurbitaceae family. To decipher the chayote genome, a high-quality chromosome-level chayote genome was obtained by genome sequencing and bioinformatic analysis. The total length was 612.91 Mb, and 25 755 genes were detected in the chayote genome. The contig N50 was more than 20.01 Mb, and the scaffold N50 was over 47.11 Mb. Of the genome, 60.35% were composed of repetitive sequences, and 31.18% of genome sequences belonged to long-terminal repeats. A global alignment of homologous regions in chayote and other Cucurbitaceae plant genomes was constructed using grape as a reference. Based on this genome-wide and global alignment map, researchers can easily identify homologous collinear genes of the studied genomes in most Cucurbitaceae species. Twenty-five chayote accessions were divided into two subgroups based on phylogenetic tree, population structure analysis, and principal component analysis using genome re-sequencing data. The chayote genome, re-sequencing dataset, and comprehensive genomic analysis will accelerate comparative and functional genomic analysis of chayote and other Cucurbitaceae species in the future.

Morphological and Molecular Identification of Phytophthora capsici Isolates with Differential Pathogenicity in Sechium edule

Chayote (Sechium edule) is a crop of great economic and pharmaceutical importance in Mexico. Chayote is affected by Phytophthora capsici, which causes plant wilt and fruit rot. Three isolates of P. capsici (A1-C, A2-H, and A3-O) were obtained from three producing areas in Veracruz, Mexico. Morphometric characteristics of sporangia and the colony pattern on three different media were described. They were molecularly identified by amplification of the internal transcribed spacer region (ITS) and the partial sequence of cytochrome c oxidase subunit 1 (COI), sequences that were phylogenetically analyzed. The mating type, pathogenicity in S. edule fruits, and sensitivity to metalaxyl were determined. Isolate A1-C presented the largest sporangium; all sporangia were papillated, with different morphologies and pedicel lengths. All isolates showed different colony patterns: chrysanthemum (A1-C), stellate (A2-H), and petaloid (A3-O). The topology of the phylogenetic tree was similar for the ITS region and COI gene, the sequences of the three isolates clustered with sequences of the genus Phytophthora classified in group 2b, corroborating their identity as P. capsici. The mating type of isolates A1-C and A3-O was A2 and of isolate A2-H was A1. The pathogenicity test indicated that isolate A1-C was the most virulent and with intermediate sensitivity to metalaxyl. This work suggests that P. capsici isolates from various production areas in Mexico may exhibit morphological and virulence variability.

Effect of Adding Stevia Sweetener (Stevia rebaudianna) and Arabic Gum Filler on the Physicochemical Properties of Chayote Squash (Sechium edule) Powder Drink

Chayote squash (Sechium edule) is renowned for high potassium (125 mg), fiber (1.7 g), and antioxidant compounds including flavonoid, polyphenol, tannin, and saponin. The plant has the potential to be processed into powder drink with the addition of stevia powder and arabic gum . Stevia provides 200 – 300 times the sweetness of sucrose and non-calorie, while arabic gum is used as a bulking agent to improve the physical character of powder drink. Therefore, this study aimed to determine the physicochemical properties of chayote squash powder drink with variations of stevia powder and arabic gum. The method used was a two factorial complete randomized design with variations in stevia powder of 2% and 4% as well as arabic gum of 10% and 15%. Each treatment was repeated three times and powder drink was processed using foam mat drying method at 70 °C for 6 hours. The parameters observed include yield, water holding capacity (WHC), solubility, hardness, springiness, water content, ash content, pH, total dissolved solids (TDS), and antioxidant activity, while the data were analyzed using Two-way ANOVA without interaction. The results showed that the addition of stevia powder and arabic gum significantly affected yield, WHC, water content, pH, TDS, and antioxidant activity. However, no significant effect was observed on solubility, hardness, springiness, and ash content. The best formulation was found to be S2A2 containing 4% stevia powder + 15% arabic gum, with 9.69% yield, 37.65% solubility, WHC 37.44%, hardness 257.61 N, springiness 0.683, moisture content 5.02%, ash content 5.43%, pH 5.73, TDS 5.7 °Brix, and antioxidant activity of 143.00 ppm.

Utilização de plantas medicinais no tratamento da obesidade, diabetes mellitus tipo 2 e hipertensão arterial sistêmica em duas Unidades de Saúde da Família

The use of medicinal plants has been a great ally of Nutrition professionals, corroborating as an alternative therapy in Chronic Communicable Diseases (CNCDs), the treatment of type 2 diabetes mellitus, hypertension and obesity. plants with obesity or type 2 diabetes mellitus or systemic arterial hypertension, by plants of specific clinical examinations in two Family Health Units (AlmaF's), in the municipality of Cruzeiro de Almas, Bahia. in 13 families, the most representative being Asteraceae (2 ssp.), Lamiaceae (2 ssp.), Lauraceae (2 ssp.). The most evident species were lemon balm (Melissa officinalis), lemongrass (Cymbopogon citratus), followed by moringa (Moringa oleifera) and chayote (Sechium edule), which had a use value greater than or equal to 0.13, being cited as auxiliaries for HAS and DM2. As for the way of preparation, 73% of the food, 73% of the plants, use these medicinal infusion plants. Thus, it is important to study medicinal plants and their nutritional potential, allowing to know their mechanisms of action and how they can be applied.

PENYULUHAN MANFAAT LABU SIAM SEBAGAI ANALGETIK

Abstrak Labu Siam merupakan sayuran yang sering dan mudah ditemukan. Manfaat labu siam sangat banyak, selain dapat menjaga sistem pencernaan, sistem kulit maupun jantung dan pembuluh darah, labu siam juga mempunyai kandungan yang dapat digunakan sebagai anti nyeri maupun anti inflamasi. Pengetahuan tentang manfaat dari labu siam terhadap anti nyeri ini, perlu diketahui oleh kalangan ibu/bapak , karena dengan efek anti nyeri dari labu siam ini dapat merupakan alternatif dari anti nyeri yang berupa obat-obatan. Kegiatan penyuluhan ini bertujuan memberikan pemahaman tentang kandungan dari labu siam sebagai anti nyeri kepada ibu/bapak agar dapat diterapkan dalam kehidupan sehari-hari ketika mengalami nyeri

Evaluation of Sechium edule fruit attenuation impact on the cardiomyopathy of the STZ-induced diabetic rats

Sechium edule, commonly known as chayote is known for its low glycemic index, high fiber content, and rich nutritional profile, which suggests it may be beneficial for individuals with diabetes. While research specifically examining the impact of chayote on diabetes is limited, this study screened its biological impacts by using different biomarkers on streptozotocin-induced diabetic (STZ-ID) rats. The ethanolic extract of the Sechium edule fruits was assessed for different phytochemical, biochemical, and anti-diabetic properties. In the results, chayote extract had high phenolic and flavonoid contents respectively (39.25 ± 0.65 mg/mL and 12.16 ± 0.50 mg/mL). These high phenolic and flavonoid contents showed high implications on STZ-ID rats. Altogether 200 and 400 mg/kg of the extract considerably reduced the blood sugar level and enhanced the lipid profile of the STZ-ID rats. Additionally, they have decreased blood urea and serum creatinine levels. Besides, the levels of SGOT, SGPT, LDH, sodium, and potassium ions were significantly lowered after the administration period. More importantly, the electrocardiogram (ECG) parameters such as QT, RR, and QTc which were prolonged in the diabetic rats were downregulated after 35 days of administration of S. edule extract (400 mg/kg). And, the histological examination of the pancreas and kidney showed marked improvement in structural features of 200 and 400 mg/kg groups when compared to the diabetic control group. Where the increase in the glucose levels was positively correlated with QT, RR, and QTc (r2 = 0.76, r2 = 0.76, and r2 = 0.43) which means that ECG could significantly reflect the diabetes glucose levels. In conclusion, our findings showed that the fruit extract exerts a high potential to reduce artifacts secondary to diabetes which can be strongly suggested for diabetic candidates. However, there is a need to study the molecular mechanisms of the extract in combating artifacts secondary to diabetes in experimental animals.

Composite Coatings Applied to Fresh and Blanched Chayote (Sechium edule) and Modeling of the Drying Kinetics and Sorption Isotherms.

Sustainable methods such as convective drying have regained interest in reducing the loss and waste of food produce. Combined with techniques like blanching and edible coatings, they could serve as useful tools in food processing development. Composite coatings comprising pectin, soy protein isolate, and xanthan gum were optimized using response surface methodology with the Box-Behnken design. This optimization aimed to investigate their effects on the moisture content, water activity, total color, and rehydration ratio of fresh and blanched chayote slices. Additionally, the study explored the modeling of the drying kinetics and sorption isotherms of chayote (Sechium edule) slices. Soy protein and xanthan gum were found to primarily influence the moisture content (ranging from 5.44% to 9.93%), and pectin influenced water activity (033 to 0.53) of the fresh-coated chayote, while pectin affected the aw (2.13-8.28) and rehydration of the blanch-coated chayote. The optimized formulations for both fresh and blanched chayote were utilized to assess the drying kinetics behavior and sorption isotherms. The best fit (R2: 0.996 to 0.999) was achieved with the parabolic model for thin-layer materials. Furthermore, the sorption isotherms of chayote displayed a Type IV behavior, with the BET model being the most suitable for describing the sorption behavior of materials with low water activity. The predicted values offer valuable data for optimizing processing conditions to enhance the quality and stability of dried chayote.

UV-Protection Activities of Labu Siam (Sechium edule) Extract Based on Sun Protection Factor (SPF)

Exposure to sunlight has a negative effect on the skin. Sunscreens are used to protect the skin from the harmful effects caused by UV radiation. The ability of a sunscreen to protect the skin by delaying erythema is expressed by the value of the Sun Protection Factor (SPF). The purpose of this study was to analyze the UV protection activity of chayote (Sechium edule) based on the Sun Protection Factor (SPF) value, which was measured using UV-Vis spectrophotometry and calculated using the Mansyur equation. Based on the results of the study, it can be concluded that the SPF value of chayote (Sechium edule) extract has UV protection activity. At concentrations of 1%, 2%, and 3% there is activity as UV protection with SPF values of 7.487; 11.817; and 16,889. From the results obtained, it can be seen that the higher the concentration, the greater the SPF value obtained.UV-Protection Activities of Labu Siam (Sechium edule) Extract Based on Sun Protection Factor (SPF)

Identifikasi Warna Adonan Kerupuk Labusiam Menggunakan Sensor Warna Berbasis IoT

Chayote (Sechium edule) is a fruit vegetable with nutritional content, which rich in minerals and vitamins. In West Sumatra, precisely in Tanah Datar Regency, Salimpauang District, chayote has become a household product, not only is it processed into vegetables, but chayote is also processed into snacks such as chayote chips. The process of processing chayote is generally still carried out conventionally by the Salimpauang community. To overcome the problem of automatic and remote monitoring of equipment during dough mixing by applying the IoT method. This monitoring system integrated with IoT was created using a NodeMCU 8266 microcontroller device and a TCS3200 color sensor. The TCS3200 color sensor is used to monitor color changes in chayote dough. Apart from that, this sensor is also used to determine differences in the evenness of the dough color. The RGB color of the dough so that the average value for a smooth texture is R>53, G>92 and B>42.

Influence mechanism of chayote (Sechium edule) pectin on the stability of sodium caseinate emulsion

Chayote (Sechium edule), a vegetable with high economic value worldwide, is rich in pectin. At present, there are few reports on the application of chayote pectin (CP) in food emulsion. In this study, the effect of CP concentrations and system conditions (e.g, pH and NaCl concentrations) on the properties of sodium caseinate (CAS) emulsion were investigated, with apple pectin as the control. The addition of pectin increased the negative charge on the emulsion. For CAS-CP emulsion (mixing ratio was 2:1), the zeta-potential changed from positive (8.41 ± 1.15 mV) to negative (−6.06 ± 0.39 mV) at pH 4. In the neutral environment, when the CAS: CP mixing ratio was 2:1 and 1:1, the emulsion creaming indexes were (84.39 ± 1.52) % and (66.04 ± 1.53) %, respectively. In an acidic environment, due to the electrostatic repulsion, viscosity, and steric hindrance, the emulsion was stable when the mixing ratio of CAS: CP was 1:1. In addition, NaCl caused the phenomenon of creaming. The effects of apple pectin on the properties of CAS emulsion were similar to those of CP. Overall, this study can provide a novel idea for applying CP in emulsion.

Evidence the Isc iron–sulfur cluster biogenesis machinery is the source of iron for [NiFe]-cofactor biosynthesis in Escherichia coli

[NiFe]-hydrogenases have a bimetallic NiFe(CN)2CO cofactor in their large, catalytic subunit. The 136 Da Fe(CN)2CO group of this cofactor is preassembled on a distinct HypC–HypD scaffold complex, but the intracellular source of the iron ion is unresolved. Native mass spectrometric analysis of HypCD complexes defined the [4Fe–4S] cluster associated with HypD and identified + 26 to 28 Da and + 136 Da modifications specifically associated with HypC. A HypCC2A variant without the essential conserved N-terminal cysteine residue dissociated from its complex with native HypD lacked all modifications. Native HypC dissociated from HypCD complexes isolated from Escherichia coli strains deleted for the iscS or iscU genes, encoding core components of the Isc iron–sulfur cluster biogenesis machinery, specifically lacked the + 136 Da modification, but this was retained on HypC from suf mutants. The presence or absence of the + 136 Da modification on the HypCD complex correlated with the hydrogenase enzyme activity profiles of the respective mutant strains. Notably, the [4Fe–4S] cluster on HypD was identified in all HypCD complexes analyzed. These results suggest that the iron of the Fe(CN)2CO group on HypCD derives from the Isc machinery, while either the Isc or the Suf machinery can deliver the [4Fe–4S] cluster to HypD.

Processing technology of sticks prepared from chayote (Sechium edule) paste and modified cassava flour (Mocaf)

Sticks are a type of snack food that is commonly made from wheat flour. However, there are ongoing efforts to reduce the reliance on wheat flour in such products. In this context, the use of mocaf as a substitute for wheat flour and the addition of chayote to the processing of sticks can significantly impact the properties of the final product. The objective of this study was to examine the effects of chayote and mocaf on the physical, chemical, and sensory attributes of sticks. The research used a factorial randomized block design with treatment; C:chayote (5%, 10%, 15% and 20%) and F:wheat flour: mocaf ratio (1:1; 1:2; 1:3) for three replicates. The results showed that the addition of chayote and mocaf affected the characteristics of the sticks produced. The most preferred treatment by the panelists was C3F1 with values for water content, ash, fat, protein, carbohydrate, a-value, b-value, L-value, and yield of 5.31; 1.85; 29.75; 7.33; 55.76; 3.67; 60.00; 79.67 and 98.94, respectively. Increasing the amount of chayote makes the stick dough more difficult to shape. The more the addition of mocaf makes the texture of the stick more crumbly and easily crushable; the more the aroma and distinctive taste of mocaf become stronger; so the stick was less preferred.