Acid phosphatase in the tubers of Dioscorea species and its purification from the white yam (D. rotundata poir)

Acid phosphatase activity was determined in 15 cultivars from four species of yam. A 12-fold purification of the enzyme from Dioscorea rotundata (cv. chikakwondo) gave a homogeneous preparation as demonstrated by polyacrylamide gel electrophoresis. This enzyme preparation has an apparent molecular weight of 115 000 ±2000 and an optimum activity at a pH of 5·20 and a temperature of 50°C. The K_m of the enzyme is 3·81 mM with disodium p-nitrophenylphosphate (p-NNP) as a substrate. The energy of activation, heat of activation, energy of inactivation and heat of inactivation are 7·0, 6·4, 4·41 and 4·34 kcal M^?1, respectively. Although it has very little activity with most organic phosphoric acid esters, it is significantly inhibited by Ca²⁺, Hg²⁺ and EDTA and activated by Mg²⁺. The enzyme has a half-life of 50,17 or 13 days, respectively, when stored at 6-8°C, 0°C or room temperature (29±2°C).     

Effect of heating,pH and thermoradiation on inactivation of Vibrio vulnificus

The effects of heating, thermoradiation and pH (5·5 to 7·0) on inactivation of V. vulnificus cells in buffers, oyster and fish homogenates were studied. Cells were more sensitive to thermoradiation than heating or radiation alone. Synergistic effects were observed during thermoradiation of V. vulnificus (10⁷ cells ml^-1) at 40°C in buffer (pH 5·5), in fresh oyster (pH 6·2) and in fresh fish (pH 6·7). This synergistic effect was also noted when the same number of cells in fresh fish homogenates were irradiated at 45°C. Inactivation of cells varied depending on the environment and were more pronounced in buffers than in oyster or fish homogenates. The D₁₀ (dose in kGy inactivating 90% of cells) at 25·C was 0·078 in buffer (pH 7·0), 0·125 in oyster (pH 6·2) and 0·187 in fish (pH 6·7), but at 35°C, the D₁₀ values were 0·054, 0·093 and 0·125 kGy, respectively. Low initial numbers of cells (10 ml^-1) in pH 7·0 buffer were rapidly inactivated by thermoradiation (40·C) compared to high cell number (10⁷ ml^-1) and the D₁₀ (kGy) was 0·024 for the former and 0·047 latter. These D₁₀ values (kGy) were 0·046 and 0·093 in fresh oysters (pH 6·2), 0·093 and 0·109 kGy in fresh fish (pH 6·7), for the low and the high cell numbers, respectively following thermoradiation at 40°C.     

A new process for preparing transparent alkalised duck egg and its quality

When fresh duck (Anas plotyrhyncus) eggs (pH 8·0–8·5) are heated, their albumen develops a turbid gel. Through appropriate alkalisation (pH 11·5–12·8), the gel's transparency can be increased. The transparency of the heated duck egg-white is affected by pH value, heating temperature, heating rate and salt concentration. This research deals with the process for preparing the transparent alkalised duck egg and the change in its quality when stored. If fresh duck eggs are pickled in a solution of 42 g NaOH+50 g NaCl litre^?1 (25·3°C) for 8 days, removed, put in a water bath and heated at 70°C for 10 min they become transparent, their hardness and penetration increasing with storage. Total bacterial count and volatile basic nitrogen also increase with storage. The total bacterial count and the volatile basic nitrogen were 4·6 × 10⁶ cfu g^?1, 0·32 mg g^?1 when stored at a temperature of under 25°C for 4 weeks, respectively.     

Purification and properties of polyphenol oxidase in head lettuce (Lactuca sativa)

Polyphenol oxidase (EC 1.10.3.1) in head lettuce (Lactuca sativa L) was purified by ammonium sulphate fractionation, ion exchange chromatography and gel filtration. The enzyme was found to be homogeneous by polyacrylamide gel electrophoresis. The molecular weight of the enzyme was estimated to be about 56 000 amu by Sephadex G-100 gel filtration. The purified enzyme quickly oxidised chlorogenic acid (5-caffeoyl quinic acid) and (—)-epicatechin. The K^m values for the enzyme, using chlorogenic acid (pH 4·5, 30°C) and (—)-epicatechin (pH 7·0, 30°C) as substrate, were 0·67 mM and 0·91 mM, respectively. The optimal pH of chlorogenic acid oxidase and (—)-epicatechin oxidase activities were 4·5 and 7·8, respectively, and both activities were stable in the pH range 6–8 at 5°C for 20 h. Potassium cyanide and sodium diethyldithiocarbamate markedly inhibited both activities of the purified enzyme. The inhibitory effect of metallic ions such as Ca²⁺, Mn²⁺, Co²⁺ and Ni²⁺ for chlorogenic acid oxidase activity was stronger than that for (—)-epicatechin oxidase activity.     

The enzymic release of fatty acids from phosphatidylcholine in green peas (Pisum sativum)

‘Phospholipid acyl-hydrolase’ (PLAH), an enzymic activity releasing fatty acid from phosphatidylcholine (PC), has been identified and characterised in green peas. The K_m value for PC dipalmitoyl ester was 0·167 mm. The enzymic activity possessed a pH optimum of 5·6 and was stable for 20 min only at that pH value. The optimum temperature was 45°C and thermal sensitivity was indicated by a 94% decrease in activity upon exposure of the enzyme to 55°C for 3 min, and by an exponential decrease in activity upon storage at 4°C for 1 week. The enzyme was optimally activated by 2·0 mm calcium chloride at pH 5·6, and the optimal concentration of sodium dodecyl sulphate was 0·75 mg ml^?1. Pea PLAH was non-competitively inhibited by sodium cyanide, EDTA and p-chloromercuribenzoate, with no activity in the presence of mercuric chloride. The results from this study are related to those of other workers on lipid-degrading enzymes in peas, and a pathway is proposed for the enzymic degradation of endogenous lipids in fresh or unblanched frozen peas during post-harvest storage.     

The influence of temperature on shortening and rigor onset in beef muscle

At sufficient ATP concentration and temperatures below about 15°C, pre-rigor beef muscles (neck muscles) contract; this phenomenon is known as cold shortening. There is also a contracture at higher temperatures occurring just before rigor onset which is called rigor shortening. While rigor shortening starts in neck muscles at pH around 6·3–6·0 and at about 2 μMol ATP/g muscle, cold shortening can begin at pH around 7·0 and the full ATP concentration (4 μMol ATP/g) in the muscle. Shortening can take place as long as there is no irreversible formation of the actomyosin complex in the muscle, i.e. before rigor onset occurs, which can be measured by intermittent loading of the muscle. The degree of extensibility which follows starts to decrease at the moment of rigor onset. This irreversible loss of extensibility at temperatures between the freezing point (?1°C) and physiological temperatures (38°C) starts at various pH values and ATP concentrations in the muscle. At 38°C the rigor onset occurs at pH 6·25 and about 2 μMol ATP/g muscle, dropping at 15°C to pH 5·75 and 1 μMol ATP/g muscle. At 0°C, as at all temperatures below 10°C, the loss of extensibility at medium loads (about 250 g/cm²) begins shortly after cold shortening. This loss of extensibility is reversible by increasing the load or raising the temperature. The irreversible loss, or rigor onset, however, occurs at 0°C with pH of 6·1–6·2 and 1·8–2·0 μMol ATP/g muscle. Thus, the onset of rigor is influenced by more than one factor. Temperature, pH and ATP concentration each play a rôle.Maximum loss of extensibility or completion of rigor is reached between 10°C and 38°C at pH 5·5–5·6 and less than 0·5 μMol ATP/g muscle. At 0°C the completion of rigor takes place at pH 6·0, but still at 0·5 μMol ATP/g muscle. The latter fact shows that the completion of rigor is solely dependent on the ATP concentration in the muscle; nevertheless, the pH of rigor completion is higher in the extreme cold shortening range. This is apparently due to a different pH/ATP relationship in muscles at low temperatures.The results are discussed in terms of changes in the concentration of Ca²⁺ ions and ATP.The results are of particular interest for the handling of hot-boned meat; that is, for both the cooling of pre-rigor muscle and the use of hot-boned meat for processing.     

Carp Sarcoplasmic Reticulum Changes Due to Heat Treatment

Electron microscopy revealed that heat treatment in the range 35–55°C caused no observable change in membrane structures of the sarcoplasmic reticulum (SR). Proteins with molecular weights about 200 and 400 kDa, (probably dimers and tetramers of Ca²⁺-ATPase, respectively) were observed in SDS-PAGE when the light SR was treated at 49 and 55°C respectively. Ca²⁺ leakage from the SR was markedly enhanced with increasing temperatures, especially for the heavy SR. Results suggest that the decrease of Ca²⁺ uptake ability following heat treatment is at least partly caused by the acceleration of Ca²⁺ leakage together with irreversible denaturation of Ca²⁺-AT-Pase protein.     

Winged bean lipoxygenase—Part 2: Physicochemical properties

Winged bean lipoxygenase (linoleate: oxygen oxidoreductase EC 1.13.11.12) isoenzymes FI and FII were isolated and purified according to the method of Truong et al. (1980).FI and FII were both highly specific for linoleic acid. They exhibited optimal activity at pH 6·0 and 5·8, respectively at 30°C. An activation energy of 4·5 kcal mol^?1 was calculated for this lipoxygenase within the temperature range of 30–50°C.At 0·075% Tween 20, FI and FII had K_m values for linoleic acid of 0·44 and 0·37 × 10^?3M, respectively, compared to 0·4 × 10^?3M for the crude enzyme. Maximal activity was obtained at 1·6 × 10^?3M. Higher levels of Tween 20 inhibited the lipoxygenase activity.Both isoenzymes had identical average molecular weight of 80 000 daltons by gel filtration and SDS gel electrophoresis.FI and FII isoenzymes were strongly inhibited by Hg⁺⁺, Mn⁺⁺, Mg⁺⁺ and Fe⁺⁺⁺ and activated by Zn⁺⁺, Co⁺⁺ and Fe⁺⁺. A difference in the degree of inhibition or activation was observed between FI and FII response. Ca⁺⁺ inhibited both FI and FII but the former was more sensitive to Ca⁺⁺. KCN also inhibited the two isoenzymes.Among the antioxidants tested, butylated hydroxytoluene and butylated hydroxyanisole most effectively inhibited both FI and FII at only 10^?6M. Sulphydryl reagents such as iodoacetamide and dithiothreitol have little effect on the lipoxygenase isoenzyme activity.The lipoxygenase isoenzymes were more stable at neutral pH. The enzyme in the crude extract and especially in situ was more stable to heat treatment.     

Purification and properties of two intracellular aminopeptidases produced by Brevibacterium linens SR3

Two aminopeptidases, designated as aminopeptidase I (API) and aminopeptidase II (APII), were isolated from the disrupted cells of Brevibacterium linens SR3 and purified to homogeneity by a combination of Phenyl-Sepharose, DEAE-Sepharose, Q-Sepharose and Sepharose CL-6B chromatography. Optimal temperature for enzymatic activity was 45°C for API and 37°C for APII, and the pH optimum was found to be 8.5 for API and 8.0 for APII. Divalent metals ions like Co²⁺ and Ni²⁺ increased enzymatic activity while Ca²⁺, Cu²⁺ and Fe²⁺ had an inhibitory effect. The enzymes were strongly inhibited by EDTA, 1,10-Phenantroline and cysteine, indicating that both aminopeptidases were metalloenzymes. The K_m values of API and APII for l-leucine-p-nitroanilide were 1.0 and 0.25 mm, respectively. Native molecular masses of aminopeptidases I and II were 80 and 220 kDa after gel filtration chromatography while molecular masses of 14 and 18 kDa, were seen, after SDS-polyacrylamide gel electrophoresis.     

Synergistic effect of Sodium Chloride,temperature and pH on growth of a cocktail of spoilage yeasts: a research note

The effect of sodium chloride (0·5–10% w/v), pH (2·6–6·3) and temperature (1–22°C) were studied on the growth of a cocktail of food spoilage yeasts. The length of the lag phase and the time taken to reach the level of 10⁶cfu ml⁻¹were calculated for each set of conditions. It was found that the lag phase constituted as little as 21% of the total time to reach 10⁶cfu ml⁻¹when the yeasts were grown in favourable conditions and as much as 62% of the total time when more extreme conditions were used. It was concluded that the lag phase was the most important factor affecting the spoilage potential of chilled foods with low pH and high salt values. The single most effective factor in reducing the growth rate of yeasts was temperature. The lag phase was 15, 38, 270, 630 and 875 h when the temperature was 15, 8, 4, 2 and 1°C respectively. At any single temperature, there appeared to be a synergistic effect of NaCl and pH and under the most extreme conditions tested (1°C; pH 5·8; 6% NaCl), the lag phase was over 1000 h. These data have implications for the spoilage potential of high salt, reduced pH foods stored at chill temperatures.     

Candida albicans phosphatidylinositol synthase has common features with both Saccharomyces cerevisiae and mammalian phosphatidylinositol synthases

Phosphatidylinositol (PI) synthase (cytidine 5′-diphospho (CDP)-1,2-diacyl-sn-glycerol:myo-inositol 3phosphatidyltransferase, EC 2.7.8.11) was isolated from the microsomal cell fraction of Candida albicans. The Triton X-100 extracted enzyme was enriched 140-fold by affinity chromatography on CDP-diacylglycerol–Sepharose. The enzyme had a pH optimum at 9·5 in glycine/NaOH buffer. It had an absolute requirement for Mg²⁺ or Mn²⁺ and was inhibited by Ca²⁺ and Zn²⁺. Maximal activity was at 0·2–0·6 mm-CDP-diacylglycerol, higher concentrations inhibited the enzyme. With 2′-deoxy-CDP-diacylglycerol as the lipid substrate, optimal activity was at 0·7 mm. The K_m for myo-inositol was determined to be 0·55 mm. The optimal temperature for the PI synthase reaction was 55°C. The C. albicans PI synthase shows differences to the Saccharomyces cerevisiae enzyme, such as activation by bivalent cations, inhibition by nucleotides, temperature optimum and activation energy, but also to the human PI synthase in preference for the lipid substrates, inhibition by nucleoside monophosphates and stabilization by Mn²⁺ and phospholipids.     

Purification and characterization of highly active and stable polyphosphatase from Saccharomyces cerevisiae cell envelope

Saccharomyces cerevisiae cell envelope polyphosphatase was isolated in highly active and stable form by extraction from cells with zwittergent TM-314 followed by chromatography of the extract on phosphocellulose and QAE-Sephadex in the presence of 5 mM -MgCl₂, 0·5 mM -EDTA and 0·1% Triton X-100. The enzyme possessed a specific activity of 220 U/mg and after 30 days retained 87% of its activity at ?20°C. Polyphosphatase molecular mass was determined to be about 40 kDa by gel filtration and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The enzyme hydrolysed polyphosphates with various chain lengths (n = 3–208), had low activity for GTP and did not split pyrophosphate, ATP and p-nitrophenylphosphate. On polyphosphates with chain lengths n = 3, 9 and 208, K_m values were 1·7 × 10^?4, 1·5 × 10^?5 and 8·8 × 10^?7 M respectively. Polyphosphatase was most active and stable at pH 6·0–8·0. The enzyme showed maximal activity at 50°C. The time of half inactivation of polyphosphatase at 40, 45 and 50°C was 45, 10 and 3 min, respectively. In the absence of divalent cations and also with Ca²⁺ or Cu²⁺, the enzyme showed practically no activity. The ability of divalent cations to activate polyphosphatase was reduced in the following order: Co²⁺ > Mg²⁺ > Mn²⁺ > Fe²⁺ > Zn²⁺. Polyphosphatase was completely inhibited by 1 mM -ammonium molybdate and 50 μM -Zn²⁺ or Cu²⁺ (in the presence of Mg²⁺).     

Feasibility of using dialysis for determining calcium ion concentration and pH in calcium-fortified soymilk at high temperature

Abstract: Dialysis was performed to examine some of the properties of the soluble phase of calcium (Ca) fortified soymilk at high temperatures. Dialysates were obtained while heating soymilk at temperatures of 80 and 100 °C for 1 h and 121 °C for 15 min. It was found that the pH, total Ca, and ionic Ca of dialysates obtained at high temperature were all lower than in their corresponding nonheated Ca‐fortified soymilk. Increasing temperature from 80 to 100 °C hardly affected Ca ion concentration ([Ca²⁺]) of dialysate obtained from Ca chloride‐fortified soymilk, but it increased [Ca²⁺] in dialysates of Ca gluconate‐fortified soymilk and Ca lactate‐fortified soymilk fortified with 5 to 6 mM Ca. Dialysates obtained at 100 °C had lower pH than dialysate prepared at 80 °C. Higher Ca additions to soymilk caused a significant (P≤ 0.05) reduction in pH and an increase in [Ca²⁺] of these dialysates. When soymilk was dialyzed at 121 °C, pH, total Ca, and ionic Ca were further reduced. Freezing point depression (FPD) of dialysates increased as temperature increased but were lower than corresponding soymilk samples. This approach provides a means of estimating pH and ionic Ca in soymilks at high temperatures, in order to better understand their combined role on soymilk coagulation.     

Isoelectric fractionation and some properties of a protease from soyabean seeds

A protease, capable of hydrolysing benzoyl DL -arginine p-nitroanilide(BAPA), and L-amino acid β-naphthylamide derivatives, was purified, by isoelectric focusing in the region pH 3–6, from dormant and 6-day germinated soyabean seeds. The enzyme was focused at pH 4·80. The K_m value using BAPA as substrate was found to be 5·03 × 10⁻⁴M . Maximum activity of the enzyme towards BAPA was obtained in the pH 8·2–8–5 region. Slight activation was observed in the presence of 0·05 M concentration of Ca²⁺ and Mg²⁺ ions. The protease lacked caseinolytic activity, and was not inhibited by Kunitz soyabean trypsin inhibitor.     

Purification and Some Properties of Glutaminase fromActinomucor taiwanensis,Starter of Sufu

Glutaminase of Actinomucor taiwanensis was purified approximately 96-fold with a yield of 18%, by sequential fractionation with ammonium sul-phate, anion exchange with DEAE-Sepharose CL-6B and gel filtration with Sephacryl S-200. The pH and temperature optima of purified glutaminase were 8·0 and 45°C, respectively. Glutaminase was stable at a temperature up to 35°C and at pH values of 6·0–8·0. The molecular weight was 80000 as determined from SDS-PAGE. The enzyme activity was markedly inhibited by HgCl₂. In the presence of 100 g litre⁻¹ NaCl, the enzyme activity was inhibited 50%.     

Purification,crystallisation and characterisation of carboxypeptidase from wheat bran

A carboxypeptidase was purified and crystallised from wheat bran. Disc gel electrophoresis at pH 4·0 and ultracentrifugal analysis revealed that the enzyme was essentially homogeneous. The sedimentation constant and isoelectric point were determined to be 6·3 S and 6·0, respectively. The molecular weight of the enzyme was estimated to be 118,000 by a gel filtration method. The enzyme liberated carboxyl terminal amino acid residues from a wide range of N-substituted dipeptides and tripeptides which contain l-proline. It had a pH optimum at pH 4·0 for Z-Glu-Tyr (Z-benzyloxycarbonyl). The K_m and k_cat values for Z-Glu-Tyr at pH 4·0 and 30°C were 0·19 mm and 20 s^?1, respectively. The enzyme hydrolysed Z-Gly-Pro-Leu-Gly-Pro and bradykinin sequentially at pH 4·0 from their carboxyl terminal amino acid residues. The enzyme activity was completely inhibited by DFP.     

Purification and Some Properties of a Protease from Sorghum Malt Variety KSV8–11

A protease from sorghum malt variety KSV8–11 was purified by a combination of dialysis against 4 M sucrose, ion‐exchange chromatography on Q‐Sepharose (Fast flow), gel filtration chromatography on Sephadex G‐100 and hydrophobic interaction chromatography on Phenyl Sepharose CL‐4B. The enzyme was purified 5‐fold to give a 14.1% yield relative to the total activity in the crude extract and a final specific activity of 1348.9 U mg^?1 protein. SDS‐PAGE revealed a single migrating protein band corresponding to a relative molecular mass of 16 KDa. Using casein as substrate, the purified protease had optimal activity at 50°C and maximal temperature stability between 30°C and 40°C but retained over 64% of its original activity after incubation at 60°C for 30 min. The pH optimum was 5.0 with maximum stability at pH 6.0 but 60% of the activity remained after 24 h between pH 5.0 and 8.0. The protease was inhibited by Ag⁺, Ca²⁺, Co²⁺, Fe²⁺, Mg²⁺, iodoacetic acid (IAA) and p‐chloromercuribenzoate (p‐CMB), stimulated by Cu²⁺, Sr²⁺, phenylmethylsulfonyl‐fluoride (PMSF) and 2‐mercaptoethanol (2‐ME) while Mn²⁺ and ethylenediaminetetraacetic acid (EDTA) had no effect. The purified enzyme had a K_m of 18 mg·mL^?1 and a V_max of 11.1 μmol · mL^?1 · min^?1 with casein as substrate.     

Sensitivity of multidrug-resistant Salmonella typhimurium DT104 to organic acids and thermal inactivation in liquid egg products

A mixture of four Salmonella typhimurium DT104 strains and a mixture of four S. typhimurium non-DT104 strains were examined for their ability to grow in tryptic soy broth (TSB) acidified with acetic, lactic, citric, or malic acids at pH 5·4, 4·4, and 3·7. Significantly (P<0·05) higher numbers of S. typhimurium DT104 cells were detected at pH 4·4 and 4·0 in TSB acidified with acetic acid and at pH 4·4 and 3·7 in TSB acidified with lactic acid compared to non-DT104 cells. Acid-shocked and non-shocked (control) cells were plated on TSA (pH 7·3) acidified with lactic acid at pH 5·4, 4·4, and 4·0 and on TSA (pH 7·0±0·2) containing 0·5, 2·5, and 5% sodium chloride. Populations of acid-shockedS. typhimurium DT104 and non DT104 cells recovered on acidified or salt-supplemented TSA were significantly (P<0·05) lower than those of non-shocked cells. A significantly lower number of acid-shocked non-DT104 cells recovered on TSA at pH 5·4, compared to acid-shocked DT104 cells, suggests that DT104 cells may be more resistant to acid shock and subsequent exposure to acid pH. D values and z values of acid-shocked or non-shocked cells of DT104 and non-DT104 strains in liquid whole egg (WE), egg yolk (EY), egg white (EW), whole egg+10% salt (WES), and egg yolk+10% salt (EYS) were determined. Differences in thermal sensitivity of the two types of cells were few. Rates of thermal inactivation of S. typhimurium DT104 cells indicate that the USDA pasteurization process would eliminate >8 log₁₀cfu ml⁻¹of EW heated at 57°C and >11 log₁₀cfu ml⁻¹of WE, EY, WES, or EYS heated at 61°C. D values of acid-shocked DT104 and non-DT104 cells heated in liquid egg products were significantly (P<0·05) lower than those of respective non-shocked cells.     

Effect of pH-dependent,stationary phase acid resistance on the thermal tolerance of Escherichia coli O157:H7

The ability of pH-dependent, stationary phase acid resistance to cross-protect Escherichia coli O157:H7 against a subsequent lethal thermal stress was evaluated using microbiological media and three liquid foods. Three strains were grown for 18 h at 37°C in acidogenic (TSB+G, final pH 4·6–4·7) and non-acidogenic (TSB-G, final pH 7·0–7·2) media to provide stationary phase cells with and without induction of pH-dependent acid resistance. The cells were then heated in BHI broth (pH 6·0) at 58°C, using a submerged coil apparatus. The TSB+G grown strains had greatly increased heat resistance, with the heating time needed to achieve a five-log inactivation, being increased two- to four-fold. The z -values of TSB+G and TSB-G grown cells were 4·7°C and 4·3°C, respectively. Increases in heat resistance with TSB+G-grown E. coli O157:H7 were also observed using milk and chicken broth, but not with apple juice. However, cross-protection was restored if the pH of the apple juice was increased from 3·5 to 4·5. The data indicate that pH-dependent acid resistance provides E. coli O157:H7 with cross-protection against heat treatments, and that this factor must be considered to estimate this pathogen's thermal tolerance accurately.     

Flow behaviors of fruit and stem extracts from Korean cactus (Opuntia humifusa)

Water extracts from the fruit and stem of Korean cactus (Opuntia humifusa, OH) showed a prototypical pseudo-plastic behavior. The pseudo-plasticity was increased with increasing concentration and decreasing temperature. The extract from the stems showed higher shear stress, consistency, and yield stress than that from fruits. The flows were examined at different concentrations, temperatures, pH, and salt content. The activation energies from fruits and stems increased from 4.127×10³ to 1.584×10³ J/kg·mol and from 16.162×10³ to 10.014×10³ J/kg·mol, respectively, as concentration increased. The concentration-dependant constant K1 from fruits and stems decreased from 0.233 to 0.185 mPa·s and from 30.476 to 66.198mPa·s, respectively, as temperature increased. The viscosity from fruits and stems increased as pH increased, while decreased as Ca²⁺ concentration increased. The unusual flow behaviors of stems and fruits might play a major role in developing food products using OH extracts.