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Enzymatic desizing using α-amylase is the conventional and eco-friendly method of removing starch based size. Conventionally, enzymes are drained after completion of process; being catalysts, they retain their activity after reaction and need to be reused. Immobilization allows the recovery of enzymes to use them as realistic biocatalyst. This study aims to recover and reuse of α-amylase for desizing of cotton via immobilization.

This paper investigates the application of α-amylase immobilized on Chitosan and Eudragit S-100 for cotton fabric desizing. A commercial α-amylase was immobilized on reversibly soluble-insoluble polymers to work out with inherent problems of heterogeneous reaction media. The immobilization process was optimized for maximum conjugate activity, and immobilized amylases were applied for grey cotton fabric desizing.

The desizing performance of immobilized amylases was evaluated in terms of starch removal and was compared to free enzyme. The immobilized amylases showed adequate desizing efficiency up to four cycles of use and were recovered easily at the end of each cycle. The amylase immobilized on Eudragit is more efficient for a particular concentration than chitosan.

Immobilization associates with insolubility and increased size of enzymes which lead to poor interactions and limited diffusion especially in textiles where enzymes have to act on macromolecular substrates (heterogeneous media). The selection of support materials plays a significant role in this constraint.

The commercial α-amylase was covalently immobilized on smart polymers for cotton fabric desizing. The target was to achieve immobilized amylase with maximum conjugate activity and limited constraints. The reversibly soluble-insoluble polymers support provide easy recovery with efficient desizing results in heterogeneous reaction media.

The α‐amylase activity of ten human saliva samples was measured using phadebas, iodine and gel‐diffusion procedures. Highly significant correlations (p = 0.001) were found between the results of the three methods, namely phadebas and iodine r = –0.907, phadebas and gel diffusion r = +0.928, and iodine and gel diffusion r = –0.948. The suitability of the three methods for use in an educational context is discussed.

The purpose of this paper is to evaluate the inhibition activity of Tribulus terrestris L. (T. terrestris) fruits extracts with solvents of increasing polarity against α-glucosidase and α-amylase, and to determine the inhibition mode of the most effective extract against both enzymes.

Hexane, acetone, ethanol and aqueous extracts of T. terrestris fruits were prepared using ultrasonic sequential extraction and analyzed for their α-amylase and α-glucosidase inhibitory activities by specific assay for each enzyme. The modes of inhibitions were detected using Lineweaver–Burk plots.

T. terrestris fruits extracts showed inhibition activity against α-glucosidase and α-amylase which was in the dose-dependent manner. Hexane extract had the highest α-glucosidase inhibition activity (IC₅₀ = 27.28 μg/ml, p = 0.003), followed by acetone and ethanol extracts (IC₅₀ = 60.58 μg/ml and IC₅₀ = 84.21 μg/ml, respectively). The inhibition mode of hexane extract was noncompetitive. While acetone extract showed the highest inhibition activity against α-amylase (IC₅₀ = 6.18 mg/ml, p = 0.002), hexane and ethanol extracts showed no significant difference (IC₅₀ = 13.04 mg/ml and IC₅₀ = 14.20 mg/ml, respectively, p = 0.09). The inhibition mode of acetone extract was competitive.

T. terrestris fruits extracts had strong inhibition activity against α-glucosidase and α-amylase, and they can be used as a promising anti-diabetic agent.

Salak (Salacca zalacca) is an underutilised fruit. The bioactivities of this fruit have rarely been studied scientifically. Thus, the present study aimed to determine the antioxidant activity of extracts derived from the peel, fruit and kernel of the Salak fruit, as well as the hypoglycemic and anti-hypertensive properties of Salak peel extracts.

The peel, fruit and kernel of the Salak were extracted using distilled water, methanol and ethanol. Antioxidant activities, angiotensin-converting enzyme (ACE) and alpha-amylase inhibition properties of the extracts were estimated via in vitro standard methods. Besides, the total phenolic content (TPC) and total flavonoid content (TFC) of the extracts were also determined in the present study. The antioxidant activities of different parts of Salak extracts were determined by ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) methods. Percent of radical scavenging properties were calculated via DPPH assay. The hypoglycemic and anti-hypertensive properties of Salak peel were evaluated using alpha-amylase inhibition and ACE assays, respectively.

Fruit extracts of Salak in methanol were found to exhibit the highest TPC (10.27 ± 0.12 mg GAE/g), TFC (11.04 ± 0.89 mg CE/g) and antioxidant properties amongst all samples whereby the TPC and TFC were strongly correlated with antioxidant activities. On the other hand, distilled water extracted Salak kernel showed to have the lowest TPC (0.53 ± 0.05 mg GAE/g), TFC (0.37 ± 0.01 mg CE/g) and antioxidant properties amongst all the Salak extracts. Peel extracts exhibit comparable antioxidant activities with fruit extracts in the current findings. In addition, peel extracts indicated some extend of ACE and alpha-amylase inhibition activities regardless of the solvents used. Methanol and ethanol peel extracts indicated no significant difference (p < 0.05) ACE (98%) and alpha-amylase (90%) inhibition activities. However, distilled water extracted Salak peel showed significantly lower ACE and alpha-amylase inhibition in comparison to methanol and ethanol peel extracts.

The present findings suggested that the fruit of Salak exhibits the highest antioxidant properties, followed by the peel and lastly, the kernel, which shows the lowest antioxidant properties amongst all the samples. The results also indicated that the peel extracts have ACE and alpha-amylase inhibition activities.

The purpose of this paper is to determine the α‐amylase and α‐glucosidase inhibitory properties of grains of some red and white varieties of rice from India.

Methanolic extracts of different rice varieties were analyzed for their α‐amylase and α‐glucosidase inhibitory properties. Total phenol and total anthocyanin contents were measured.

The white varieties of rice grains showed weak α‐glucosidase inhibitory activity and no α‐amylase inhibitory activity. The red varieties of rice grains showed good α‐glucosidase and α‐amylase inhibitory activities. The activities in these red varieties of rice, as determined by the IC₅₀ values, were found to be correlated to total anthocyanin content. α‐glucosidase inhibitory activity of cyanidin‐3‐glucoside, the anthocyanin reported from rice grains was studied. But the IC₅₀ values of different red varieties of rice were much less than that of cyanidin‐3‐glucoside indicating higher activity of red rice grain extracts than the purified pigment. This might be due to synergistic activity with other components present in rice extract.

The report shows hypoglycaemic potential of red varieties of rice grains.

The purpose of this paper is to propose that the measurement of salivary amylase activity is an effective index to evaluate the stress of a ship navigator for safe navigation training and education.

Evaluation comes from the simulator and actual on‐board experiments. The subjects are real captains who have unlimited licenses and cadets who are senior students at Kobe University, navigation course. Stress is evaluated for several situations where a ship navigator makes a lot of decisions, in this case in a narrow passage, entering a port and leaving a port.

Salivary amylase activity occurs when a ship navigator makes a decision regarding ship handling and collision avoidance. By measuring salivary amylase activity when a student is under duress, cadets' ship‐handling training can be evaluated while onboard a vessel.

Future research will develop cross‐indices with the salivary amylase activity and other physiological indices (nasal temperature and heart rate variability (R‐R interval)), complementary to each other. The salivary amylase activity registers the stress quickly on the spot. Then the nasal temperature and R‐R interval registers the trend and the quick response to the stress (mental workload).

The paper describes an effective index which is useful for evaluating a ship navigator's stress for safe navigation.

Ship navigator's skill and cadet's on‐board training have been evaluated according to performance and a questionnaire as a quantitative evaluation; moreover, stress is evaluated using salivary amylase activity.

Natural dyes are mostly used for dyeing of natural fibre textiles to improve their eco-friendly features. For successful commercial use of natural dyes, the appropriate and standardized dyeing techniques need to be adopted. Appropriate scientific techniques or procedures need to be derived from scientific studies on dyeing methods, dyeing process variables, dyeing kinetics and compatibility of selective natural dyes with minimal use of hazardous chemicals.

In the present study, different enzymes (protease, amylase, xylanase, pectinase, phytase) were used efficiently with Rubia dye by using simultaneous and two-step processes; both the processes were developed with an aim for conservation of time and energy, for the ease of industrial use. The highlights of the study are twofold: eco-friendly natural dyeing by using enzyme replacing metal mordant and room temperature dyeing, which is a completely new concept.

Experiments showed that enzymatic treatment can give good colour strength to silk fabric using Rubia as a dye source and has good potential for commercial dyeing. It is a non-toxic dye. Use of enzymes were a deliberate attempt to avoid metal mordanting in silk dyeing, as it would make textile dyeing eco-friendlier. The order of reactivity of enzymes in one-step process was found to be protease > phytase > xylanase > amylase > pectinase. Similarly, for two-step dyeing process, the order of reactivity of enzymes observed was protease > amylase > xylanase = pectinase > phytase. Protease enzyme was the best option in both the cases. Overall, it can be concluded that in the case of enzymatic treatment, the two-step process was better in terms of larger K/S values, colour coordinate values and dye adherence.

A new domain of room temperature dyeing technique has been introduced.

In the present study, different enzymes (protease, amylase, xylanase, pectinase, phytase) were used efficiently with Rubia dye by using simultaneous and two-step processes; both the processes were developed with an aim for conservation of time and energy, for the ease of industrial use. The highlights of the research are twofold: eco-friendly natural dyeing by using enzyme replacing metal mordant and room temperature dyeing, which is a completely new concept. Overall, the ease of use for industrial application. Rubia dye from Sri Lanka has been used in conjunction with different enzymes to show that metal mordanting can be easily replaced by the use of eco-friendly and biodegradable enzymes. The most attractive feature of this study is the low-temperature dyeing at 30-40°C. For any dyeing house, this process can be easily adapted on jigger, winch or even in continuous padding machine. Good fastness properties and dye adherence have been the other highlights of this study.

This study aims to investigate the effect of the copresence of ferrous (Fe²⁺) ions and sodium dodecyl sulfate (SDS) on the activity of an amylase enzyme during the desizing of greige viscose fabric for potential industrial applications. The removal of starches is an essential step before processing the fabric for dyeing and finishing operations. The authors tend to accomplish it in eco-friendly and sustainable ways.

The experiments were designed under the Taguchi approach, and the results were analyzed using grey relational analysis to optimize the process. The textile properties of absorbency, reducing sugars, bending length, weight loss, Tegawa rating and tensile strength were assessed using the standard protocols. The control and optimized viscose specimens were investigated for certain surface chemical properties using advanced analytical techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA).

The results demonstrate that the Fe²⁺ concentration and process time were the main influencing factors in the amylolytic desizing of viscose fabric. The optimized process conditions were found to be 0.1 mm Fe²⁺ ions, 3 mm SDS, 80°C, 7 pH and 30 min process time. The copresence of Fe²⁺ ions and SDS promoted the biodesizing of viscose fabric. The SEM, Fourier transform infrared spectroscopy, XRD and TGA results demonstrated that the sizing agent has efficiently been removed from the fabric surface.

The amylase desizing of viscose fabric in the presence of certain metal ions and surfactants is a significant subject as the enzyme may face them due to their prevalence in the water systems. This could also support the biodesizing and bioscouring operations to be done in one bath, thus making the textile pretreatment process both economical and environmentally sustainable.

The authors found no report on the biodesizing of viscose fabric in the copresence of Fe²⁺ ions and the SDS surfactant under statistical multiresponse optimization. The biodesized viscose fabric has been investigated using both conventional and analytical approaches.

Literature has shown that phenolic acids and flavonoids are bearing with hypoglycemic and anti-adipogenic properties. Therefore, this study aims to evaluate the possibility of phenolic-rich soya bean husk powder extract (SHPE) in combating diabetes and obesity using in vitro models.

The hypoglycemic properties were evaluated by determining the ability of SHPE (25-100 µg/mL) in inhibiting a-amylase and a-glucosidase enzymes and in triggering insulin secretion in BRIN-BD11 cells. Murine 3T3-L1 adipocytes were used for evaluating the anti-adipogenic properties of SHPE through the determination of relative lipid accumulation, triglyceride content and glycerol-3-phosphate dehydrogenase (GPDH) activity.

The hypoglycemic properties of SHPE was in the dose-dependent manner, where 100 µg SHPE/mL exhibited a significant higher (p < 0.05) a-amylase inhibitory activity (56.8 ± 0.11 per cent) and insulin secretion activity (0.73 ± 0.02 µg/l) against other concentrations. In contrast to the aforementioned findings, a significant lower a-glucosidase inhibitory activity (52.0 ± 0.44 per cent) was also observed in 100 µg SHPE/mL. Nevertheless, findings revealed that all the SHPE were able to inhibit the activity of a-amylase and a-glucosidase and stimulated the insulin secretion in BRIN-BD11 cells. On the other hand, the anti-adipogenic properties of SHPE were in the reverse dose-dependent manner, where 100 µg SHPE/mL demonstrated a significant lower (p < 0.05) relative lipid accumulation (48.5 ± 0.03 per cent), intracellular triglyceride content (5.7 ± 0.07 mg/dL) and GPDH activity (1.0 ± 0.01 mU/mL). These findings reflected that 100 µg SHPE/mL was a potent anti-adipogenic agent when compared with other concentrations. In conclusion, soya husk could emerge as a potential hypoglycemic and anti-adipogenic agents in in vitro models.

This was the first study to explore the effectiveness of phytochemicals derived from soya bean husk in ameliorating hyperglycemia and adipogenesis. Promising findings that derived from the present study could enable the scientists to re-evaluate the potential use of agricultural wastes, especially in the formulation of nutraceuticals.

The purpose of this paper is to evaluate the antioxidant and type II diabetes related enzyme inhibition properties of phenolic extract from raw and traditionally processed Indian under‐utilized food legume grains, Bauhinia purpurea L. (purple camel's foot seeds).

The methanolic extract was prepared from the raw and traditionally processed seed samples and analyzed for total phenolic content. The antioxidant activity and type II diabetes related enzyme inhibition properties of methanolic extract and their relationship with phenolic content was demonstrated.

The methanolic extract of raw seed materials contained total free phenolic content of 14.45±1.62 g catechin equivalent/100 g extract DM. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1203 mmol Fe[II]/mg extract), inhibition of ß‐carotene degradation (45.37 percent) and scavenging activity against DPPH (63.60 percent) and superoxide (42.14 percent) radicals were exhibited by the raw samples. Further, it also recorded 80.69 percent of α‐amylase and 63.74 percent of α‐glucosidase enzyme inhibition characteristics under in vitro starch digestion bioassay. Sprouting+oil‐frying caused an apparent increase on the total free phenolic content, antioxidant and free radical scavenging capacity, while soaking+cooking as well as open‐pan roasting treatments show diminishing effects.

Identification of suitable processing technique offered a good strategy to improve the phenolic content and health relevant functionality of B. purpurea seeds, which could be envisaged as a dietary ingredient in the formulation of supplementary foods with therapeutic value to manage type II diabetic patients.