Optimization of pectinase extraction from mango (Mangifera indica cv. Chokanan) peel using response surface methodology

Today pectinases (EC 3.2.1.15) have become an integral part of the food and feed industry and plant peel could be a potential source of pectinase. Thus, the main objective of the study was the optimization of pectinase extraction from mango (Mangifera indica cv. Chokanan) peel. For this purpose, response surface methodology (RSM) was employed to optimize the extraction conditions and the effect of independent variables, namely temperature (-25 to +25°C), mixing time (2–10 min) and pH of buffer (1–8), on specific activity, storage stability, temperature stability and surfactant agent stability of pectinase from mango peel was investigated. The study demonstrated that using optimum temperature, mixing time and pH of buffer, protected pectinase during extraction, as indicated by low activity and low stability loss. It was found that the interaction effect of mixing time and buffer content improved the pectinase stability, and pH of buffer had the most significant effect on specific activity of the pectinase. The ideal condition of 2.5°C temperature, 6 min mixing time at pH 4.5 was established for pectinase extraction from mango peel. The result indicated that the optimized extraction of pectinase from mango peel provides high activity and stability of pectinase in harsh conditions, which makes the enzyme suitable for use in various types of industry and biotechnological applications. Furthermore, there was not any significant (p>0.05) difference between the experimental and predicted values. This ensured that the response surface models used to indicate property changes of pectinase as a function of enzyme extraction conditions were sufficient

Characterization of serine protease from mango (Mangifera indica cv. Chokanan) peel

Mango (Magnifera indica cv. Chokanan) is one of the most popular tropical fruits in the world and currently ranked 5th in total world production among the major fruit crops. Mango peel is one of the major wastes of food and beverage industries, however, it can be used as a valuable, economic and available media sources for commercially producing the natural enzymes. This study aimed at characterizing serine protease which was previously purified from mango peel by alcohol salt aqueous two-phase system (ATPS). The molecular weight of purified protease was determined with sodium dodecyl polyacrylamide sulfate gel electrophoresis (SDS-PAGE) to be 65 kDa, it showed maximum activity (> 80%) at pH 4-10 and exhibited high thermal stability (>90%) for 60 min at 65°C with the highest activity at 70°C and at pH 8. Its activity was strongly inhibited by PMSF, but not by EDTA, pepstatin, or cysteine protease inhibitors. The activity of the protease was activated by Ca2+and Mg2+ while Li+, Na+, K+ and Sn2+ had no effect on the protease activity. However, reduction in the activity of protease was observed in the presence of Ba2+, Zn2+, Pb2+, Co2+, Mn2+ and Cu2+. The enzyme was resistant to denaturation by sodium dodecyl sulfate and the non-ionic surfactants such as Tween 80 and Triton X-100. The properties of serine protease extracted from mango peel and discussed in this study made it applicable in industrial processes that are performed under high temperature, in alkaline medium, or in the presence of denaturants and surfactants

Probiotics your friendly gut bacteria

The functional food concept has in recent years, moved progressively towards the development of dietary supplements that may stimulate gut microbial composition and activities. The rationale behind these advances is consequent to the realization that gut microflora has profound influence on the host’s health. The human gastrointestinal tract (GIT) represents an ecosystem of the highest complexity and is very dynamic in composition. The micro biota exists in a commensal, symbiotic or an antagonist microbial relationship. Among more than 400 species of bacteria present in the GIT of an adult human being, bifidobacteria and lactobacillus are considered to be the most beneficial to human health. Members of these genera are thought to enhance digestion, adsorption of nutrients, prevention of colonization by pathogens, decreasing serum cholesterol and stimulation of immune responses. The ability of these bifidobacteria and lactobacilli to ferment non-digestible oligosaccharides may be an important characteristic which enables them to establish themselves in the colon. Studies were undertaken by researchers in our laboratory to elucidate the probiotic characteristics and effects of the bifidobacteria species isolated from the human GIT and to propose screening, cultivation and preservation and delivery techniques for this bacterium

Probiotic: your friendly gut bacteria

The functional food concept has in recent years, moved progressively towards the development of dietary supplements that may stimulate gut microbial composition and activities. The rationale behind these advances is consequent to the realization that gut microflora has profound influence on the host’s health. The human gastrointestinal tract (GIT) represents an ecosystem of the highest complexity and is very dynamic in composition. The micro biota exists in a commensal, symbiotic or an antagonist microbial relationship. Among more than 400 species of bacteria present in the GIT of an adult human being, bifidobacteria and lactobacillus are considered to be the most beneficial to human health. Members of these genera are thought to enhance digestion, adsorption of nutrients, prevention of colonization by pathogens, decreasing serum cholesterol and stimulation of immune responses. The ability of these bifidobacteria and lactobacilli to ferment non-digestible oligosaccharides may be an important characteristic which enables them to establish themselves in the colon. Studies were undertaken by researchers in our laboratory to elucidate the probiotic characteristics and effects of the bifidobacteria species isolated from the human GIT and to propose screening, cultivation and preservation and delivery techniques for this bacterium

Purification of pectinase from mango (Mangifera indica L. cv. Chokanan) waste using an aqueous organic phase system: a potential low cost source of the enzyme

As a novel method of purification, an aqueous organic phase system (AOPS) was employed to purify pectinase from mango waste. The effect of different parameters, such as the alcohol concentration (ethanol, 1-propanol, and 2-propanol), the salt type and concentration (ammonium sulfate, potassium phosphate and sodium citrate), the feed stock crude load, the aqueous phase pH and NaCl concentration, were investigated in the recovery of pectinase from mango peel. The partition coefficient (K), selectivity (S), purification factor (PF) and yield (Y, %) were investigated in this study as important parameters for the evaluation of enzyme recovery. The desirable partition efficiency for pectinase purification was achieved in an AOPS of 19% (w/w) ethanol and 22% (w/w) potassium phosphate in the presence of 5% (w/w) NaCl at pH 7.0. Based on the system, the purification factor of pectinase was enhanced 11.7, with a high yield of 97.1%

Characterization of pectinase from mango (Mangifera indica Cv. chokanan) peel

Today, pectinase has emerged as an integral part of the food and feed industries. Plant peel could be a potential source of pectinase, which has been extracted and purified from mango (Mangifera indica cv. Chokanan) peel using the aqueous two-phase system (ATPS). In the present study, the effects of temperature, pH and metal ions on the stability and activity of pectinase were investigated. In addition, the molecular weight of this enzyme was determined as 31 kDa with SDS-PAGE. Pectinase showed the highest enzyme activity at 60ºC for 30 min after incubation at different temperatures (20 to 80ºC). Also, this enzyme has been shown to be thermostable because more than 90% of residual enzyme activity was retained at temperatures of 20 to 60ºC for 30 min. Pectinase was incubated in different pH from 3 to 9 and the highest enzyme activity was achieved at pH 8. Furthermore, the enzyme was stable at pH 5 to 9 after enzyme incubation at different pH for 24 h at 4ºC. Activity of the enzyme was significantly decreased at pH 3 and 9 due to the protein denaturation. Pectinase activated by Ca2+ showed that this cation has an important effect on activity and stability of the enzyme; but Li+, Na+ and K+ had no effect on its activity. Also, the reduction in the activity of pectinase was observed in the presence of Fe2+, Cu2+, Mn2+, Zn2+ and Al3+. Therefore, pectinase extracted from mango peel has potential applications in various industries like food and feed because it is thermostable under high temperatures in either alkaline medium or when there is the presence of metal ions

Purification of a novel protease enzyme from kesinai plant (Streblus asper) leaves using a surfactant–salt aqueous micellar two-phase system: a potential low cost source of enzyme and purification method

Serine protease from kesinai leaves was purified for the first time by a surfactant–polymer aqueous micellar two-phase system. The effectiveness of different types and concentrations of non-ionic surfactants (Pluronic series and X-114) on the partitioning behaviour of the protease was evaluated. The results showed that the enzyme preferentially partitioned into the bottom surfactant-rich phase, while the hydrophilic amino acid preferred the top aqueous phase. This distribution of the enzyme is due to the hydrophobic interaction of the serine protease with the hydrophobic lid of the micelle core in the bottom phase. The influence of different types of salts (K2SO4, KH2PO4, KCl and KNO3) on the purification and selectivity of the enzyme was determined. The protease partitioning in the bottom phase increased in the presence of KNO3, which confirmed that the salt was able to improve the protein solubility in bottom phase and increase the hydrophobic interaction between the two phases. In addition, the protease from the bottom phase was re-extracted to a new aqueous phase solution to remove and recycle the surfactant. Addition of potassium thiocyanate led to the partitioning of the enzyme in top aqueous phase due to high ionic strength of SCN−, which forced the lighter micellar phase toward the upper position of the system. A high purification factor (10.3) and yield of 92 % of the enzyme were achieved in a solution of 31 % of Pluronic L61 using 0.3 % KNO3 and 50 % crude feedstock at pH 7.0

Characterization of polyphenol oxidase from mango (Mangifera indica L. cv. Chokanan) peel

Plant polyphenol oxidase showed positive effect in the production of coca, black tea and flavonoid-derived colorants and antioxidants. High activity and stability in a wide range of pH and temperature of plant enzyme make it suitable and also inexpensive for use in industry. For these reasons, there is growing interest in seeking more plant sources of polyphenol oxidase. Mango (Mangifera indica L. cv. Chokanan) peel can be a potential source of polyphenol oxidase, which has been extracted and purified from peel of mango using the aqueous two-phase system (ATPS). In the present study, the effects of different temperatures, pH, inhibitors and metal ions on the stability and activity of polyphenol oxidase from mango peel were investigated. In addition, the molecular weight of this enzyme was estimated at 133 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The highest enzyme activity of polyphenol oxidase to catalyze catechol in sodium phosphate buffer was achieved at 55°C at pH 5.5. Furthermore, the enzyme was stable at temperatures of 10 to 60°C and pH 3 to 6. Beta-mercaptoethanol, ascorbic acid, l-cysteine and pyrogallol were effective inhibitors of the enzyme. Also, activity of polyphenol oxidase was increased in the presence of some metal ions such as Ca2+, Mg2+ and Cu2+ which implies that the enzyme involved metal ions. Therefore, polyphenol oxidase extracted from mango (Mangifera indica L. cv. Chokanan) peel has potential applications in various industries because it is thermostable under high temperatures in either acidic medium, or when there is the presence of metal ions

Purification of serine proteases from mango (Mangifera indica cv. Chokanan) peel using expanded bed adsorption: optimisation using response surface methodology

Proteolytic enzymes or proteases are a class of proteins ubiquitously found in all organisms; they act as catalysts and perform diverse vital functions. In plants, proteases of plant origin play a vital function from the mobilisation of storage proteins during germination to the initiation of cell death and senescence. Proteases derived from plants are extensively employed in food industries because of the wide range of good solubility, substrate specificity, activity over a wide pH and temperature range and high stability in extreme conditions. Plant peel could be a potential source of proteases due to the easy purification methods, low levels of interfering substances during purification, and good yield of proteases. An expanded bed adsorption (EBA) technique was used to purify serine proteases from mango peel. Response surface methodology (RSM) with a central composite design was employed to optimise the EBA technique. Analysis of independent factors as a function of flow rate, temperature, pH of buffer and salt revealed different effects of these four factors on the studied parameters (total protein, total activity, specific activity, purification factor, yield, storage, thermal and pH stability). It was demonstrated that the serine protease could be recovered with a yield of 82% and a purification factor of 11.3 after a single step elution with 1.0 M NaCl. No significant (p>0.05) difference was found between the experimental and predicted values, thus ensuring the adequacy of the RSM employed for describing the changes in the properties of the serine protease as a function of operating conditions using EBA

Effects of low temperature storage and thermisation on the quality of raw and heat treated milk

ON-FARM MILK QUALITY STUDIES 1.0 Three surveys were conducted approximately at three months apart to evaluate the quality of raw milk produced from dairy farms in the south-west of Scotland. The farms assinged to the study were within the scheduled route of the three road tankers supplied by the local bulk milk haulage contractor of the Scottish Milk Marketing Board. The sequence of milk collection by each road tanker during the first survey was noted and the sequence was repeated in the subsequent surveys. SIMULATED BULK MILK SILO STUDIES 2.0 A simulated study was conducted to measure the effects of blending and subsequent storage of raw milk at low temperatures on the quality of pasteurised milk made from it. EFFECTS OF THERMISATION ON MILK QUALITY 3.0 Two preliminary trials were conducted to compare the effects of a range of thermisation heat treatments on bacterial counts and alkaline phosphatase content of milk. THE EFFECTS OF EXTENDED RAW MILK STORAGE ON THE EFFECTIVENESS OF THERMISATION AND THE EFFECTS OF DOUBLE HEAT TREATMENTS ON PASTEURISED MILK QUALITY 4.0 Three trials were conducted to measure the effects of extended storage of raw milk for 2, 4 and 7 days at