2023 Vol. 38, No. 4
Display Method:
2023, 38(4): 387-400.
doi: 10.19303/j.issn.1008-0384.2023.04.001
Abstract:
Objective Effects of N applications on the yield and quality of currently popular varieties of long grain indica rice cultivated in Hubei were studied. Method In Jianghan Plain of Hubei province, the high-quality, high-tolerance, long-grain indica rice, Huanghuazan, was compared on yield and quality under the N application rates of 120 kg·hm−2 (N1), 150 kg·hm−2 (N2), 180 kg·hm−2 (N3), and 240 kg·hm−2 (N4) with Lixiang 85, Nongxiang 32, Yuzhenxiang, and Taiyouexiangsimiao. Result The grain yields of the varieties of rice increased with increasing N application to peak at an average of 8.3 t·hm−2 under N2 representing a 3.8% over N1, 7.8% over N3, or 18.6% over N4. The aboveground dry matters of the rice accumulated from heading to maturity stage was enhanced by the increased N. The weights of leaves, stems, and ears reached the highest levels under N4, N3, and N2, respectively. N2 also produced the optimal proportions of stems, leaves, and ears of 29.8%, 17.7%, and 52.5%, respectively, at maturity. The increased N promoted the yield on polished grains which reached the significantly highest level among all treatments at 52.6% under N2. The treatments induced little change in the visual appearance of the grains. However, a significant alternation occurred to the straight-chain starch as the RVA of the polished rice grain exhibited a great degradation, low reduction, and highly desirable taste under N2. Conclusion At the N application rate of 150 kg·hm−2 (N2), a yield of 6.5–9.5 t·hm−2 on the rice could be expected. Of the 4 varieties, Taiyouexiangsimiao displayed a high yield and properties appropriate for processing and was considered most suitable for industrial applications, while Lixiang 85, with its appealing eating quality, best fitting for home consumption.
2023, 38(4): 401-409.
doi: 10.19303/j.issn.1008-0384.2023.04.002
Abstract:
Objective Agronomic trait combining abilities and correlation with crop yield of 4 newly bred male sterile rice lines were studied. Method Based on the 6×6 NC II design, 36 hybrids were generated from 6 sterile and 6 restorer rice lines.Combining abilities and correlation with crop yield of 8 agronomic traits of the hybrids were analyzed. Result (1) The variance of general combining ability (GCA) on the traits of the sterile and restorer lines or between the two lines were significantly or extremely significantly different.Aside from plant height, the variance of special combining ability (SCA) on the traits also reached a significant or extremely significant level.It indicated that most of the agronomic traits were affected by both additive and non-additive factors.(2) The generalized heritability on plant height, panicle length, 1000-grain weight, and spikelet count per panicle were high.The narrow heritability on plant height, panicle length, and 1000-grain weight were also high (＞70%) and largely controlled by the additive effect of the genes; whereas those on seed setting rate, effective panicle per plant, and yield per plant relatively low (＜50%) and basically shaped by the non-additive effects of the genes and environment.(3) The 1000-grain weight, panicle length, effective panicle per plant, and seed-setting rate significantly or extremely significantly correlated with the yield per plant.A path analysis indicated that it was the 1000-grain weight and effective panicle number per plant that directly governed the yield, whereas the intertwined promotional and restrictive actions of the various agronomic traits exerted their effect. Conclusion Among the 4 newly bred sterile rice lines, Wuliang A and Jiudu A had higher GCA and SCA on most agronomic traits and were preferable for breeding applications.The 1000-grain weight and effective panicle number per plant were the key agronomic traits that related to the rice crop production.
2023, 38(4): 410-416.
doi: 10.19303/j.issn.1008-0384.2023.04.003
Abstract:
Objective Critical factors in the ethylene signal transduction pathway involving the post-harvest physiological deterioration (PPD) of cassava were investigated. Method One of the possible ethylene response factors (ERFs) in Manihot esculenta cv.SC8, MeERF1.2, was cloned using RT-PCR to analyze the expressions during PPD. Physicochemical properties, conserved domain, genetic evolutionary relationship, and protein structure of the gene were studied with bioinformatics tools. Distribution of MeERF1.2 in the plant cells was verified by online software and subcellular localization. Result MeERF1.2 had an ORF of 660 bp encoded 188 amino acids with a molecular weight of 25.04 kD and a pI of 5.61. The protein contained an AP2 domain showing a high sequence similarity of 88.74% with the HbERF1B-like gene. It was localized in the nucleus and significantly upregulated during PPD from 0 to 6, 12, and 48 h displaying an apparent induction trend in the process. Conclusion MeERF1.2 was one of the ERFs induced in cassava tubers during PPD and played a vital role in the signal transduction pathway of the plant.
2023, 38(4): 417-422.
doi: 10.19303/j.issn.1008-0384.2023.04.004
Abstract:
Objective To improve the fertility purity of beet monogerm cytoplasmic male sterile lines and maintainers. Method Forty pairs of molecular markers from a collection of 620 monogerm cytoplasmic male sterile and maintainer sugar beet germplasms were identified.All genetically mixed markers in the sterile and maintainer plants were given specific codes and recorded.Subsequently, a morphological observation was carried out in the field to exclude genetically impure plants. Result The verification of heredity purity by molecular markers revealed 92 DNA including 73 in the maintainers mixed with that of the sterile plant and 19 in the sterile lines contaminated with that belonged to the maintainer.The field examination on pollens and grains identified 122 plants (as compared to 92 isolated by the molecular marker verification) with 73 maintainers and 49 sterile lines to be promiscuous.In addition, polygerm plants were unexpectedly found in the lot that could have grown from the accidentally included seeds. Conclusion By excluding adulterated plants in the field, the purity on heredity of sterile and maintainer lines could be assured.The procedure would provide the prerequisite essential for accurate genetic diversity determination and successful preparation of binary sterile sugar beet lines.
2023, 38(4): 423-430.
doi: 10.19303/j.issn.1008-0384.2023.04.005
Abstract:
Objective Effect of plant growth promoting rhizobacteria (PGPR) containing ACC deaminase on the productivity of rose bushes was studied. Method A pot experiment was conducted on White Lichee , a variety of roses commonly used commercially for cut flowers.Rhizobacteria carrying the plant growth promoter, ACC deaminase, were added to the soil, and effects on the agronomic traits, such as plant height, stem girth, and number of branches, as well as the physiological indexes, such as chlorophyll a/b, leaf protective enzyme, MDA content, flower ethylene release, photosynthesis, and chlorophyll fluorescence, of the plants monitored. Result In comparison with control, the incorporation of F23 or F195 PGPR, respectively, resulted in the rose bushes 25.9% and 26.0% taller with higher contents of chlorophyll a and chlorophyll b; F23, 17.1% larger stem girth, significantly greater activities of urease (by 42.6%), phosphatase (by 16.3%), and sucrase (by 48.8%) in rhizosphere soil, and POD (1.78x of control) and CAT (2.07x of control) in leaf. The floral ethylene release of the bushes treated with F23 was 37.0% lower than control, while the net photosynthetic rate of the F195-treated bushes significantly rose to 1.40 times and that of F23-treated bushes 1.16 times of control. Conclusion Overall, F23 appeared to most significantly promote the growth of White Lichee rose bushes among different PGPR tested.
2023, 38(4): 431-435.
doi: 10.19303/j.issn.1008-0384.2023.04.006
Abstract:
Objective A method for bovine rotavirus (BRV) detection was developed to determine the current epidemiological status in Fujian province. Method A pair of specific primers was designed based on the BRV genome from GenBank using Oligo7.0. Reaction conditions of the RT-PCR method were optimized for the detection. Specificity, sensitivity, and repeatability of the assay were verified on 22 clinical samples. Result The newly developed method amplified only the specific fragment of BRV, not any of other common pathogens of livestock and poultry. A sensitivity of 6.86×105 copies·μL−1 was achieved. And, on the 22 clinical samples, 12 were tested positive at a rate of 54.55%. Conclusion The established RT-PCR method for BRV detection displayed high specificity, sensitivity and repeatability, which could be applied for clinical diagnosis and epidemiological investigation.
2023, 38(4): 436-443.
doi: 10.19303/j.issn.1008-0384.2023.04.007
Abstract:
Objective To understand the evolutionary relationship and pathogenicity of Mycoplasma synoviae (MS) clinical infection strains in Fujian Province. Method MS detection and isolation were performed from cleft palate and tracheal swab samples of chickens suspected of MS infection to obtain MS clinical isolates, and the vlhA gene phylogenetics of MS isolates were carried out. And also, the pathogenicity and horizontal transmission ability of MS isolates from Fujian province were evaluated using 7-day-old SPF chickens infected by eye and nasal route, including clinical symptoms and anatomical pathology, histopathology of trachea, MS re-isolation of trachea and MS antibody. Result The positive rate of MS in tracheal swabs was significantly higher than that in cleft palate swabs. A total of 9 MS isolates showed that there was diversity in the vlhA gene, and different isolates had different evolutionary sources. According to the phylogenetics of vlhA gene, 6 MS isolates were selected to infect 7-day-old SPF chickens, no obvious clinical symptoms were caused in SPF chickens from 1 to 21 days after infection. It was found that one chicken had mild air sacculitis in HI strain group at 14 and 21 days after infection and in SD6 strain group at 21 days after infection via necropsy, and other chickens including cohabitation chickens did not have obvious clinical anatomical and pathological changes. Histopathological analysis showed that there were significant differences in the tracheal lesion to different MS isolates after 7, 14, and 21 days of infection. The results showed that re-isolations of MS from trachea were with significant differences to different MS isolates, and SD19 and SD6 strains had strong horizontal transmission ability. MS antibody detection found that only 1 infected chicken and 1 cohabiting control chicken in the SD19 infection group turned positive for antibodies at 21 days after infection. Conclusion Tracheal samples were more suitable for the detection and isolation of MS. MS isolates were rather difficult causing clinicopathological changes in 7-day old SPF chickens, and also MS isolates could present and colonize in the trachea to cause histopathological lesion, and there were significant differences within different isolates. Therefore, the results laid the foundation for subsequent research on the prevention and control of Mycoplasma synoviae infection.
2023, 38(4): 444-453.
doi: 10.19303/j.issn.1008-0384.2023.04.008
Abstract:
Objective A codominance functional marker of the broad-spectrum bacterial blight resistance gene,Xa7, of rice was identified for accurate detection, generation tracking, and differentiation between homozygous and hemizygous genotypes of the gene. Methods A potential functional marker containing 4 primers was designed using Premier 5 software and based on the differences on the sequences of Xa7, xa7, and allele-free genome.The molecular distinctness of the marker in different materials was verified by PCR.Three crossbreed lines of Xa7 and their parents were inoculated with 7 bacterial blight pathogens at booting stage to examine the affected agronomic traits at maturation. Results The homozygous R084 of Xa7 could be amplified into a 91 bp band and the Nip free of allele with a 153 bp band; while the heterozygote Nip/R084, 91 bp and 153 bp bands.The candidate codominance marker, Xa7fun, amplified fragments that matched the predicted target bands.No 91 bp fragment was amplified from 18 germplasms of varied types indicating a lack of Xa7 in them.Whereas Ry1, Ry2, and Ry3 had 91 bp band suggesting the inclusion of homozygous Xa7.Under an elevated temperature, Huazhan responded to the 7 bacterial blight pathogens as highly sensitive (HS), intermediate sensitive (MS), or sensitive (S); R084 to 6 of the 7 pathogens (HNA1-4, FuJ, GDA2, GD1358, PX086, and YN24) as highly resistant (HR), intermediate resistant (MR) or resistant (R); Ry-1 to 5 pathogens (GDA2, HNA1-4, FuJ, GD1358, and YN24) as HR or MR; Ry-2 to 5 pathogens (GDA2, GD1358, HNA1-4, PXO86, and YN24) as HR or R; and Ry-3 to 6 pathogens (HNA1-4, FuJ, GDA2, GD1358, PXO86, and YN24) as HR or MR.Therefore, the infiltration of Xa7 in the crossbred and improved lines RY-1, RY-2, and RY-3 significantly accentuated the blight resistance of Huazhan. Conclusion The homozygous or hemizygous Xa7 could be accurately differentiated by the currently identified codominance functional marker Xa7fun.The Xa7 introgression did not significantly alter the critical agronomic traits in the hybridization from generation to generation and could be safely applied in breeding bacterial leaf blight resistant rice varieties．
2023, 38(4): 454-460.
doi: 10.19303/j.issn.1008-0384.2023.04.009
Abstract:
Objective Chemical composition and anti-tobacco mosaic virus (TMV) activity of Ailanthus altissima were studied to pave the way for developing an effective viral inhibitor. Methods Substrates in the n-butanol extract of leaves and branches of A.altissima plants were separated using silica gel, Sephadex LH-20, and MCI column chromatography.Chemical structures of the substrates were determined based on NMR and MS data, and anti-TMV activity of the compounds examined using the half-leaf method. Results The 17 compounds isolated from the n-butanol extract were identified to be: (1) kaempferol, (2) (2S)-3-o-octadeca-9Z, 12Z, 15Z-trienoylgycery-O-β-D-galactopyranoside, (3) hexacosane, (4) 6,9,12-octadecatrienoic acid, (5) eichlerianic acid, (6) colocasinol A, (7) caffeic acid eicosanyl ester, (8) acernikol, (9) (-)-Sakuyayesinol (10), (14S,17S, 20S, 24R)-20,24,25-trihydroxy-14,17-cylomalabarican-3-one, (11) 4-(3-butoxy-1-hydroxy-2-methoxypropyl) benzene-1, 2-diol, (12) pinnata, (13) trans-syringin, (14) gingerglycolipid A, (15) gingerglycolipid B, (16) benzyl 2-o-β-apiofuranosyl-(1→2)-β-D-glucopyranosyl-2,6-dihydroxy-benzoate, and (17) picrorhizoside C.Among them, Compounds 2, 14, and 15 were isolated from the plant for the first time.And the lignans, phenylpropanoids, or galactose lipids, such as Compounds 6, 8, 13, and 14 at concentration of 50 μg·mL−1 displayed a TMV inactivation rate greater than 50%, which was similar to that of the positive control, ningnamycin.For Compounds 6, 13, and 14, the rates were even higher than that of ningnamycin. Conclusion All 17 substances isolated from the leaves and branches of A.altissima exhibited varying degrees of inhibitory effect on TMV.The efficacy was more significant as shown by certain Lignans, phenylpropanoids, and galactose lipids.
2023, 38(4): 461-467.
doi: 10.19303/j.issn.1008-0384.2023.04.010
Abstract:
Objective Thrips hawaiiensis is a significant loquat pest. This study aimed to determine the attractive effects of single-colored sticky traps, colored sticky traps + single semiochemical, and colored sticky traps + two semiochemicals on the capture of T. hawaiiensis and beneficial insects. These findings would provide a scientific basis for the monitoring and control of thrip populations, as well as the conservation of beneficial insects in loquat orchards. Method A field experiment was conducted to compare the effectiveness of sticky traps of three different colors (yellow, blue, white) hung aboveground at varied heights (225cm, 150cm, 75 cm) in attracting the target insects. Then, at the optimal sticky trap color and hanging height, four groups of traps coated with a single seimchemical (methyl isonicotinate, MI; methyl nicotinate, MN; ethyl isonicotinate, EI; ethyl nicotinate, EN) on each trap, six groups of traps with two seimchemicals (MI+EN, MI+EI, MI+MN, MN+EN, MN+EI, EN+EI) on each trap, and one control group were placed in the orchard to compare the attractant effects of T. hawaiiensis and beneficial insects. Result White sticky traps hung 150cm aboveground attracted the greatest number of thrips. The single methyl isonicotinate semiochemical (MIWT) was most effective in attracting T. hawaiiensis, and the numbers of female, male, and total T. hawaiiensis adult captured were 4.68 times, 8.45 times, and 5.56 times, respectively, that of the control. By comparing the trapping effects of the six two semiochemicals treatments and their corresponding single semiochemical on the capture of T. hawaiiensis adults showed that all of them had antagonistic effects on female adults. However, interestingly and importantly, the captured beneficial insects of the ten semiochemical treatments, such as hoverflies, parasitic wasps, lacewings, bees, and vespids, were all lower than those of the control, and the maximum number of hoverflies captured was only 2.73 thrips per trap per day, and the ratio of trapped beneficial insects : trapped thrips of all the treatments were lower than those of the control, with MIWT treatment showing the least (1:285.33). Conclusion In the loquat flowering season, the combination of the white sticky trap and methyl isonicotinate had the strongest trapping effect on T. hawaiiensis, with the least effect on beneficial insects.
2023, 38(4): 468-474.
doi: 10.19303/j.issn.1008-0384.2023.04.011
Abstract:
Objective Accumulation and food safety of cadmium in first crop and ratoon rice were studied. Method In a greenhouse experiment, plants of Xiangliangyou 900 , touted as the “Super Rice”, were grown in pots with artificially added Cd in the soil at a rate of 0 (CK), 0.2, 0.4, 0.8, 1.2, or 1.5 mg·kg−1. Cd contents in the roots, stems, leaves, and grains of the first and ratoon crops of the rice were determined, cumulation pattern analyzed, and risk of safety for consumption assessed. Result Cd in various organs of the rice plants of both first and ratoon crops increased with increasing Cd in soil in the order of roots＞leaves＞stems＞grains. In the ratoon season, the plants contained less Cd than in the first season. The roots of the first crop plants contained Cd in the range of 0.2317–0.9581 mg·kg−1, which was 5.1%–20.5% and averaging 15.2% higher than the ratoon counterparts of 0.2128–0.7802 mg·kg−1. The stems of the first crop plants had Cd in the range of 0.0212–0.0846 mg·kg−1, which was 10.8%–42.6% and averaging 29.7% higher than the ratoon counterparts of 0.0189–0.0621 mg·kg−1. In the leaves, the first crop plants showed Cd in the range of 0.0273–0.1157 mg·kg−1, which was 10.3%–65.6% averaging 45.5% higher than the ratoon plants of 0.0245–0.0689 mg·kg−1. And in the grains, the Cd content of the first crop rice was in the range of 0.0172–0.0516 mg·kg−1, which was 12.8%–53.1% averaging 33.2% higher than 0.0150–0.0312 mg·kg−1 of the ratoon plants. Other than CK, at a same level of Cd in the pot soil, significant differences on Cd contents between the two different crops of same rice plants were observed (P＜0.05). The capacity of accumulating Cd ranked by different organs was roots＞leaves＞stems＞grains. The heavy metal risk coefficients for individual organs of the ratoon rice were all less than 1. Conclusion Cd in various organs were less in the ratoon than the first crop rice. After harvest of first crop, the regenerated roots and stems on a ratoon rice plant did not inherit or transfer the Cd. Consequently, consumption of ratoon Xiangliangyou 900 rice would mean a reduced food safety risk for the consumers.
2023, 38(4): 475-484.
doi: 10.19303/j.issn.1008-0384.2023.04.012
Abstract:
Objective Effects on plant metabolism of the widely practiced utilizing spent straws for fertilization in northeastern China corn fields were studied. Method In a field experimentation, application of either the conventional chemical fertilization (CK) or 15% reduction of chemical fertilizer with an addition of humic acid (HA), spent straws (SR), or both HA and SR (SRH) was implemented on a black soil lot of Zea mays. Physiological responses including carbon and nitrogen metabolisms to the treatments of current-season corn plants were monitored. Result The replacement of chemical fertilizer by SR enhanced the phosphoenolpyruvate carboxylase (PEPC) activity, that by HA decreased the 1,5-ribulose bisphosphate carboxylase (Rubisco) and PEPC activities, and that by SRH interacted on PEPC in the corn leaves. Although SR decreased, HA increased the sucrose phosphate synthase (SPS) activity. Both SR and HA (SRH) treatment raised the activities of sucrose synthase (SS), and combined use of HA and HA(SRH) increased the acid invertase (AI), and neutral invertase (NI) promoting the synthesis of reducing sugars that resulted in an increased total soluble sugar (TSS) and starch synthesis. SR had no significant effect, but HA had a positive effect on key enzymes involving the nitrogen metabolism of the plant. Conclusion With a 15% reduction on chemical fertilizer, addition of SRH boosted the photosynthetic efficiency and storage of photosynthetic products of corn leaves without any significant effect on the nitrogen metabolism of the plant.
2023, 38(4): 485-496.
doi: 10.19303/j.issn.1008-0384.2023.04.013
Abstract:
Objective Genes relating to prodigiosin synthesis in Serratia plymuthica ACCC 02146 were identified, and a transposon mutant library on the strain constructed. Methods Fifteen prodigiosin-producing microbes were obtained from a conservation center and a laboratory. After identification by 16S rRNA gene sequencing, they were classified according to the neighbor-joining trees. Promoter sequences of prodigiosin synthesis gene were analyzed, and color producing capacity of the individual strains evaluated. Selected strain was cloned and further studied to establish a library on the transposon mutants. Results Differed from other strains in terms of 16S rDNA and promoter sequences of the prodigiosin biosynthesis gene clusters, S.plymuthica ACCC 02146 was selected to clone the candidate gene for further investigation. A transposon mutant library was constructed subsequently. In the library, of 74 mutants showing significant variations in prodigiosin-producing ability, 25 had the insertions in pigA, pigB, pigC, pigD, and pigH, while 49 in the genes outside the cluster. On color formation, 6 strains with the mutation on maltose o-acetyltransferase gene, 4 on dihydroorotate dehydrogenase gene, 3 on MarR family of transcription factor SlyA genes, 3 on two-component transcriptional regulator RstA of the winged helix family, 3 on NAD(P)H-quinone oxidoreductase subunit I gene, 3 on NADH-quinone oxidoreductase, chain G gene, 3 on peptidylprolyl isomerase B gene, and one to two on other genes were found possibly related to significant alterations on the prodigiosin production as well. Conclusion Aside from the identified specific clusters of prodigiosin synthesis-associated genes, additional factors in the forms of enzymes, transcriptional regulators, and/or structural proteins were now speculated to also directly or indirectly contribute in varying degrees to the prodigiosin synthesis in Serratia sp.
Active Ingredients and Antioxidative and Anti-EV71 Virus Effects of Grifola frondosa Ethanol Extract
2023, 38(4): 497-505.
doi: 10.19303/j.issn.1008-0384.2023.04.014
Abstract:
Objective Active ingredients and antioxidative and anti-EV71 virus activities of the Grifola frondose extracts using varied concentration of ethanol were analyzed. Method Using 55%, 70%, and 95% ethanol solutions, a ultrasound-assisted extraction was conducted to produce concoctions from G.frondosa fruiting bodies.Content of active ingredients and efficacy of the extracts obtained with varied concentrations of ethanol as an antioxidant and anti-EV71 virus agent were determined. Result The content of polyphenols at 0.042% and that of triterpenes at 1.82% were the highest in the 95% ethanol extract (GFE95) of all concoctions.The maximal polysaccharides at 33.08% and proteins at 17.45% were found in GFE55 that used 55% ethanol for the extraction.GFE95 also showed the greatest antioxidant capacity with IC50 on scavenging DPPH, ABTS+, O2−, and H2O2 free radicals of 0.742 7 mg·mL−1, 0.741 4 mg·mL−1, 0.902 6 mg·mL−1, and 0.414 6 mg·mL−1, respectively, and a strong antiviral effect on EV71 at the concentration of 200 μg·mL−1 with the inhibition rate of 88.18%, an IC50 of 194.80 μg·mL−1, and a TI of 9.65.A Pearson’s correlation analysis indicated that the DPPH, ABTS+, and O2− free radical scavenging rates significantly correlated to the triterpenoids content with correlation coefficients of 0.992, 0.971, and 0.613, respectively (P＜0.01); the O2− and H2O2 free radical scavenging rates significantly correlated to the polyphenols with correlation coefficients of 0.921 and 0.997, respectively (P＜0.01); the anti-EV71 virus effect significantly correlated to the polyphenols and triterpenoids with correlation coefficients of 0.536 and 0.954, respectively (P＜0.01); and the triterpenoids and polyphenols significantly correlated to the antioxidative and antiviral activities of the extract. Conclusion The 95% ethanol extraction of G.frondosa optimally retrieved the active substances, such as polyphenols, triterpenes, and polysaccharides, in the fruiting bodies.The extract exhibited significant antioxidative and antiviral capacities, with which a valuable pharmaceutical material might be developed.
2023, 38(4): 506-514.
doi: 10.19303/j.issn.1008-0384.2023.04.015
Abstract:
Objective Optimization on the enzymatic extraction process of starch from turmeric was improved. Method Using fresh turmeric as raw material, the best enzyme was screened among several proteases according to the starch extraction rate. A single-factor test was conducted to define the range of the time, digestion temperature, pH and the amount of neutral protease for extraction. Based on the single-factor test results, a 4-factor, 3-level Box-Behnken response surface optimization experiment was designed on 29 treatments with 3 replicates each to determine the optimal processing conditions. Results The optimized process applied 0.13% added neutral protease in a solution at pH 6.83 held at 51.45 °C for 6.20 h to achieve 62.00% turmeric starch extraction. For practical application the conditions were modified to be pH 6.8, 52°C, and 6 h to obtain a turmeric extraction rate of 60.42%. The experimental results fitted well with the prediction model. The fitted model was in good agreement with the actual one. Conclusion The enzymatic extraction of turmeric starch was optimized by response surface methodology in preparation for industrialized production.
